Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Ken Yamaura Last modified date:2020.06.29

Professor / Surgery / Department of Clinical Medicine / Faculty of Medical Sciences

1. Kazuhiro Shirozu, Shinnosuke Takamori, Hidekazu Setoguchi, Ken Yamaura, Effects of forced air warming systems on the airflow and sanitation quality of operating rooms with non-laminar airflow systems, Perioperative Care and Operating Room Management, 10.1016/j.pcorm.2020.100119, 2020.12.
2. Jie Guo, Kazuhiro Shirozu, Tomohiko Akahoshi, Yukie Mizuta, Masaharu Murata, Ken Yamaura, The farnesyltransferase inhibitor tipifarnib protects against autoimmune hepatitis induced by Concanavalin A, International Immunopharmacology, 10.1016/j.intimp.2020.106462, 83, 2020.06, No effective treatment has been established for autoimmune hepatitis (AIH), except for liver transplantation in the fatal stage. Little is known about the roles and mechanisms of farnesyltransferase inhibitors (FTIs) in treating AIH. Thus, we investigated the specific role of the FTI, tipifarnib, in a Concanavalin A (Con A)-induced model of hepatitis. The effects of tipifarnib (10 mg/kg, intraperitoneal injection) were studied in Con A (20 mg/kg, intravenous injection)-challenged mice by histological, biochemical, and immunological analyses. Tipifarnib-treated mice were compared to phosphate-buffered saline (PBS)-treated mice. Con A caused liver injury characterized by increased plasma alanine aminotransferase (ALT) levels and marked histological changes. The increased serum ALT, interleukin-6, or interferon-γ (IFN-γ) levels were observed at 2 or 8 h; tumor necrosis factor-α levels at 2 h post-Con A administration decreased significantly in the tipifarnib group. Tipifarnib also suppressed Con A-induced activation of CD4+ cells (but not CD8+ T cells) in the liver and spleen, and also reversed the Con A-induced decrease of natural killer T (NKT) cells in the liver. Tipifarnib significantly inhibited IFN-γ production and STAT1 phosphorylation from CD4+ T cells (but not CD8+ T and NKT cells) in the liver at 2 h post-Con A administration. Tipifarnib significantly inhibited IFN-γ production by splenic CD4+ T cells at 48 h post-Con A injection in vitro. Tipifarnib also inhibited the expression of farnesylated proteins induced by Con A administration. In conclusion, tipifarnib inhibited IFN-γ derived from Con A-induced CD4+ T cell activation due to downregulated STAT1 phosphorylation, suggesting that Tipifarnib can protect against AIH..
3. Midoriko Higashi, Kenji Shigematsu, Kenji Tominaga, Kazuya Murayama, Daisuke Seo, Toshikazu Tsuda, Gen Maruta, Kohei Iwashita, Ken Yamaura, Preoperative elevated E/e’ (≥ 15) with preserved ejection fraction is associated with the development of postoperative heart failure in intermediate-risk non-cardiac surgical patients, Journal of Anesthesia, 10.1007/s00540-019-02728-z, 34, 2, 250-256, 2020.04, Purpose: Left ventricular diastolic dysfunction is an independent risk factor for adverse cardiovascular morbidities and mortalities in cardiovascular and high-risk surgical patients. However, there were only a few investigations among intermediate-risk surgical patients. This study aimed to investigate postoperative heart failure (HF) in intermediate-risk surgical patients who had preoperative diastolic dysfunction with preserved ejection fraction (EF). Methods: Consecutive patients underwent intermediate-risk surgery between January 2016 and December 2018 were retrospectively evaluated. Patients with preserved EF were divided into three groups using one of the parameters of diastolic function: the ratio of early diastolic filling velocity to the peak diastolic velocity of mitral medial annulus (E/e’) ≥ 15, E/e’ between 8 and 15, and E/e’ < 8. Postoperative HF was defined as clinical symptoms and radiological evidence and low SpO2 less than 93%. The primary outcome was the incidence of postoperative HF and its relation to preoperative E/e’. Chi-squared test, unpaired t test with Welch’s correction, and multivariate logistic regression were used for analysis. Results: In total, 965 patients were included in the final analysis. Postoperative HF developed in 36/965 (3.7%) patients with preserved EF. The incidence of postoperative HF was stratified according to the E/e’, and the rates of HF occurrence in patients with E/e’ < 8, 8–15, and ≥ 15 were 1.8%, 2.7%, and 15%, respectively (P < 0.01). Conclusion: Preoperative elevated E/e’ (≥ 15) was associated with the development of postoperative HF in intermediate-risk surgical patients with preserved EF..
4. Kazuhiro Shirozu, Kaoru Umehara, Mizuko Ikeda, Yutaro Kammura, Ken Yamaura, Incidence of postoperative shivering decreased with the use of acetaminophen
a propensity score matching analysis, Journal of Anesthesia, 10.1007/s00540-020-02763-1, 2020.01, Objectives: The incidence of postoperative shivering is known to be inversely associated with core body temperature. However, previous studies have pointed out that the threshold of shivering could be affected by peripheral temperature or anesthetic agents. These reports pointed specific drugs, though, anesthesia techniques have since advanced considerably. This study aimed to investigate factors associated with postoperative shivering in the context of the current body warming practice. Methods: The institutional clinical research ethics committee of Kyushu University approved the study protocol (IRB Clinical Research number 2019-233). This retrospective study involved 340 patients who had undergone radical surgery for gynecological cancer treatment under general anesthesia at our center from December 2012 to June 2019. Logistic regression analysis was performed to estimate the odds ratio (OR) for the incidence of postoperative shivering. Results: Postoperative shivering developed in 109 out of 340 patients. After multivariate-adjusted logistic regression, the incidences of postoperative shivering decreased significantly with increasing patient age (OR = 0.96; 95%CI: 0.93–0.98; p = 0.0004). Volatile anesthesia technique was less inclined to shiver after surgery than TIVA (OR = 0.55; 95%CI: 0.30–0.99; p = 0.04). Acetaminophen was much less used in the shivering group than in the non-shivering group (OR = 0.49; 95%CI: 0.25–0.94; p = 0.03). Conclusions: This study indicated that the development of shivering in patients receiving the anesthetic technique currently used in our hospital was associated with use of acetaminophen or volatile agents, and patient age..
5. Kobayashi A, Shirozu K, Karashima Y, Matsushita K, Yamaura K, Cerebral infarction detected after laparoscopic partial hepatectomy: case report, JA Clinical Reports,, 5, 82, 2019.12, [URL].
6. Masako Asada, Emi Oishi, Satoko Sakata, Jun Hata, Daigo Yoshida, Takanori Honda, Yoshihiko Furuta, Mao Shibata, Kosuke Suzuki, Hiroshi Watanabe, Norihito Murayama, Takanari Kitazono, Ken Yamaura, Toshiharu Ninomiya, Serum Lipopolysaccharide-Binding Protein Levels and the Incidence of Cardiovascular Disease in a General Japanese Population
The Hisayama Study, Journal of the American Heart Association, 10.1161/JAHA.119.013628, 8, 21, 2019.11, Background: Epidemiological studies have reported a link between serum LBP (lipopolysaccharide-binding protein) levels and lifestyle-related diseases. However, there have been no longitudinal studies investigating the association of serum LBP levels and the incidence of cardiovascular disease (CVD) in general populations. Methods and Results: A total of 2568 community-dwelling Japanese individuals 40 years and older without prior CVD were followed for 10 years (2002–2012). Serum LBP levels were divided into quartiles (quartile 1: 2.20–9.68 μg/mL; quartile 2: 9.69–10.93 μg/mL; quartile 3: 10.94–12.40 μg/mL; quartile 4: 12.41–24.34 μg/mL). The hazard ratios (HRs) and their 95% CIs for the incidence of CVD were computed using a Cox proportional hazards model. During the follow-up period, 180 individuals developed CVD. The age- and sex-adjusted cumulative incidence of CVD increased significantly with higher serum LBP levels (P for trend=0.005). Individuals with higher serum LBP levels had a significantly greater risk of the development of CVD after adjusting for conventional cardiovascular risk factors (quartile 1: HR, 1.00 [reference]; quartile 2: HR, 1.04 [95% CI, 0.60–1.78]; quartile 3: HR, 1.52 [95% CI, 0.92–2.51]; and quartile 4: HR, 1.90 [95% CI, 1.17–3.09]; P for trend=0.01). This association remained significant after additional adjustment for homeostasis model assessment of insulin resistance (P for trend=0.01). However, when additional adjustment was made for high-sensitivity C-reactive protein, the association was attenuated to the nonsignificant level (P for trend=0.08). Conclusions: The present findings suggest that higher serum LBP levels are associated with increased risk of the development of CVD in the general Japanese population. Low-grade endotoxemia may contribute to the pathogenesis of CVD through chronic systemic inflammation..
7. Ryohei Miyazaki, Makoto Sumie, Tadashi Kandabashi, Ken Yamaura, Resting pupil size is a predictor of hypotension after induction of general anesthesia, Journal of Anesthesia, 10.1007/s00540-019-02672-y, 33, 5, 594-599, 2019.10, Purpose: Arterial hypotension is a major adverse effect of general anesthesia. Patients with pre-existing autonomic dysfunction are at greater risk of hypotension. This study was performed to examine whether objective measurement of the pupillary light reflex is predictive of intraoperative hypotension. Methods: We studied 79 patients who underwent scheduled surgery under general anesthesia. Patients with severe cardiovascular disease or receiving antihypertensive agents were excluded. The light reflex was measured preoperatively using a portable infrared pupillometer, and the hemodynamic parameters were obtained from the anesthesia records. The patients were divided into two groups according to the development of hypotension: the hypotension and normotension groups. Multivariate logistic regression analysis was performed to determine the pupil parameters predictive of hypotension. Results: Patients in the hypotension group were older and had a greater pupil size or constriction velocity than those in the normotension group. Logistic regression analysis showed that post-induction hypotension was significantly associated with maximum pupil size or constriction velocity after adjustment for age and other clinical variables. Latency of the light reflex and the percent reduction of pupil size were not associated with hypotension. Age was a relatively strong predictor of hypotension; other confounding factors were not associated with hypotension. Conclusion: Measurement of maximum pupil size is useful to identify patients at risk for intraoperative hypotension. The influence of age must be considered during measurement of the pupil response..
8. Iwashita K, Shigematsu K, Yamaura K, Predictingoptimal peripherally inserted central venous catheter insertion depth , 手術医学, 40, 2, 61-67, 2019.06.
9. M. Higashi, K. Shigematsu, E. Nakamori, S. Sakurai, K. Yamaura, Efficacy of programmed intermittent bolus epidural analgesia in thoracic surgery
A randomized controlled trial, BMC anesthesiology, 10.1186/s12871-019-0780-0, 19, 1, 2019.06, Background: Continuous epidural infusion (CEI) has some disadvantages, such as increased local anesthetic consumption and limited area of anesthetic distribution. Programmed intermittent bolus (PIB) is a technique of epidural anesthesia in which boluses of local anesthetic are automatically injected into the epidural space. The usefulness of PIB in thoracic surgery remains unclear. In this study, we aimed to compare the efficacies of PIB epidural analgesia and CEI in patients undergoing thoracic surgery. Methods: This randomized prospective study was approved by the Institutional Review Board. The study included 42 patients, who were divided into CEI (n = 21) and PIB groups (n = 21). In the CEI group, patients received continuous infusion of the local anesthetic at a rate of 5.1 mL/90 min. In the PIB group, a pump delivered the local anesthetic at a dose of 5.1 mL every 90 min. The primary endpoints were the frequency of patient-controlled analgesia (PCA) and the total dose of local anesthetic until 36 h following surgery. Student's t-test, the chi-square test, and the Mann-Whitney U test were used for statistical analyses. Results: The mean number of PCA administrations and total amount of local anesthetic were not significantly different between the two groups up to 24 h following surgery. However, the mean number of PCA administrations and total amount of local anesthetic at 24-36 h after surgery were significantly lower in the PIB group than in the CEI group (median [lower-upper quartiles]: 0 [0-2.5] vs. 2 [0.5-5], P = 0.018 and 41 [41-48.5] vs. 47 [43-56], P = 0.035, respectively). Hypotension was significantly more frequent in the PIB group than in the CEI group at 0-12 h and 12-24 h (3.3% vs. 0.5%, P = 0.018 and 7.9% vs. 0%, P = 0.017, respectively). Conclusion: PIB can reduce local anesthetic consumption in thoracic surgery. However, it might result in adverse events, such as hypotension. Trial registration: This randomized prospective study was approved by the Institutional Review Board (IRB No. 15-9-06) of the Fukuoka University Hospital, Fukuoka, Japan, and was registered in the clinical trials database UMIN (ID 000019904) on 24 November 2015. Written informed consent was obtained from all patients..
10. Ryohei Miyazaki, Sumio Hoka, Ken Yamaura, Visceral fat, but not subcutaneous fat, is associated with lower core temperature during laparoscopic surgery, PloS one, 10.1371/journal.pone.0218281, 14, 6, 2019.06, Background Previous studies suggest that lower BMI is a risk factor for intraoperative core hypothermia. Adipose tissue has a high insulation effect and is one of the major explanatory factors of core hypothermia. Accordingly, determining the respective influence of visceral and subcutaneous fat on changes in core temperature during laparoscopic surgery is of considerable interest. Methods We performed a prospective study of 104 consecutive donors who underwent laparoscopic nephrectomy. Temperature data were collected from anesthesia records. Visceral and subcutaneous fat were calculated by computed tomography (CT) or ultrasound. For ultrasound measurements, preperitoneal fat thickness was used as an index of visceral fat. Multiple linear regression analysis was performed at 30, 60, and 120 minutes after the surgical incision to identify the predictive factors of body temperature change. The potential explanatory valuables were age, sex, BMI, visceral fat, and subcutaneous fat. Results BMI (β = 0.010, 95%CI: 0.001–0.019, p = 0.033) and waist-to-hip ratio (β = 0.424, 95%CI: 0.065–0.782, p = 0.021) were associated with increased core temperature at 30 minutes after the surgical incision. Ultrasound measured-preperitoneal fat was significantly associated with increased core temperature at 30 and 60 minutes after the surgical incision (β = 0.012, 95%CI: 0.003–0.021, p = 0.009 and β = 0.013, 95%CI: 0.002–0.024, p = 0.026). CT-measured visceral fat was also associated with increased core temperature at 30 minutes after the surgical incision (β = 0.005, 95%CI: 0.000–0.010, p = 0.046). Conversely, subcutaneous fat was not associated with intraoperative core temperature. Male sex and younger age were associated with lower intraoperative core temperature. Conclusions Visceral fat protects against core temperature decrease during laparoscopic donor nephrectomy..
11. Kazuhiro Shirozu, Keitaro Murayama, Ken Yamaura, Pupillary response as assessment of effective seizure induction by electroconvulsive therapy, Journal of Visualized Experiments, 10.3791/59488, 2019, 146, 2019.04, Electroconvulsive therapy (ECT) is reported to be effective for severe neuropsychiatric disorders. In ECT, electrical stimulation is applied to the brain, inducing seizure activity. Adequate seizure induction with ECT is associated with seizure duration, symmetrical high amplitude waveforms during slow-wave activity, postictal suppression, and activation of the sympathetic nervous system. Sympathetic nervous system activation is influenced by anesthetic agents or cardiovascular drugs during ECT. Pupillary responses can reflect sympathetic nervous activity or the degree of brain damage. Pupillary response measurement can be conducted in a simple, precise, and objective way using an automated infrared pupillometer, enabling the measurement of pupil diameter (mm) to two decimal places. The white light used for measuring light reflexes is not overly bright, and patients do not typically report discomfort. Pupillary light reflexes were measured before anesthesia induction and immediately after electrical stimulation using this equipment. Pupil diameter is typically enlarged after brain damage or sympathetic nervous activation. Adequate seizure induction using ECT could induce pupillary enlargement immediately after electrical stimulation. In the current method, the constriction ratio of pupil size was calculated automatically and compared with seizure quality. Pupillary responses immediately after electrical stimulation may provide a useful assessment of the efficacy of seizure induction with ECT..
12. Yamanokuchi T, Nakagawa T, Yamaura K, Yhoshimura C, Maeda T, Masayoshi T, Kawazoe M, Sato A, Arima H., Predictors of prolonged operation duration when using general anesthesia in a teaching hospital, Med. Bull Fukuoka Univ. , 46, 1, 51-61, 2019.03.
13. Kenji Shigematsu, Kouhei Iwashita, Ryosuke Mimata, Ryoko Owaki, Takaaki Totoki, Akira Gohara, Jingo Okawa, Midoriko Higashi, Ken Yamaura, Preoperative left ventricular diastolic dysfunction is associated with pulmonary edema after carotid endarterectomy, Neurologia medico-chirurgica, 10.2176/nmc.oa.2019-0028, 59, 8, 299-304, 2019.01, This retrospective study was aimed to investigate the association between preoperative left ventricular (LV) cardiac function and the incidence of postoperative pulmonary edema (PE) in patients undergoing carotid endarterectomy (CEA). Most patients undergoing CEA for carotid artery stenosis have concomitant heart diseases, leading to hemodynamic instability that can cause postoperative cardiac complications such as cardiac heart failure. LV diastolic function has recently been recognized as an independent predictor of adverse cardiac events in patients undergoing cardiovascular surgery. We analyzed clinical data from the anesthetic and medical records of 149 consecutive patients who underwent CEA at our university hospital between March 2012 and March 2018. LV systolic and diastolic function were evaluated by ejection fraction and the ratio of LV early diastolic filling velocity to the peak velocity of mitral medial annulus (E/e′). Postoperative PE was diagnosed based on chest X-ray and arterial gas analysis by two independent physicians. Postoperative PE was developed in four patients (2.8%). Patients with postoperative PE were not related to preoperative low ventricular ejection fraction, but had a significantly higher E/e′ ratio than those without PE (P = 0.01). Furthermore, there was an increasing trend of PE according to the E/e′ category. Preoperative LV diastolic function evaluated by E/e′ was associated with the development of postoperative PE in patients who underwent CEA. The results suggest that the evaluation of LV diastolic dysfunction could be possibly useful to predict PE in patients undergoing CEA..
14. Ryosuke Mimata, Midoriko Higashi, Madoka Yasui, Takanao Hirai, Ken Yamaura, Spinal epidural hematoma following epidural catheter removal in a patient with postoperative urgent coronary intervention and intra-aortic balloon pumping (IABP)
A case report, American Journal of Case Reports, 10.12659/AJCR.917716, 20, 1356-1359, 2019.01, Objective: Rare disease Background: It is still challenging to remove an epidural catheter in a postoperative patient receiving urgent antiplatelet and anticoagulation therapy for acute coronary syndrome. Case Report: While under general anesthesia combined with thoracic epidural anesthesia, a 72-year-old male patient underwent right radical nephrectomy for renal cell carcinoma. On postoperative day 1 (POD1), the patient experienced bradycardia and a decrease in blood pressure, and he was diagnosed acute myocardial infarction. Intraaortic balloon pumping (IABP) was induced for cardiogenic shock, and urgent thrombus aspiration and coronary balloon angioplasty were performed. On POD3, the surgeon removed the epidural catheter under both antiplatelet and anticoagulation therapy. At that time, the platelet count was 45×109/L and the activated partial thromboplastin time (APTT) was 72.2 seconds. Four hours after the epidural catheter was removed, the patient complained of bilateral fatigue in legs and developed a loss of sensation. Six hours after the epidural catheter was removed, he developed motor paralysis and became completely paralyzed in both limbs after 9 hours. At 19 hours after the epidural catheter was removed, emergency magnetic resonance imaging detected a spinal epidural hematoma at the level of Th9-11 with compression of the spinal cord. Emergency laminectomy was performed to decompress and remove the spinal epidural hematoma at 18 hours after the onset of sensorimotor symptoms. After surgery and rehabilitation, these symptoms had only slightly improved. Conclusions: In patients with urgent antithrombotic therapy for urgent percutaneous coronary intervention (PCI) with an IABP for acute coronary syndrome, the epidural catheter should not be removed until the IABP and heparin are discontinued, and platelet counts have recovered..
15. Mari Yamashita-Ichimura, Emiko Toyama, Makoto Sasoh, Hironari Shiwaku, Kanefumi Yamashita, Yuichi Yamashita, Ken Yamaura, Bladder pressure monitoring and CO2 gas-related adverse events during per-oral endoscopic myotomy, Journal of Clinical Monitoring and Computing, 10.1007/s10877-018-0122-7, 32, 6, 1111-1116, 2018.12, Per-oral endoscopic myotomy (POEM) is a minimally invasive treatment for esophageal achalasia. However, POEM has the potential risk of inducing carbon dioxide (CO2) gas-related adverse events, such as pneumoperitoneum, pneumomediastinum, and pneumothorax. The aim of this study was to evaluate the usability of bladder pressure monitoring as an index of CO2 gas-related pneumoperitoneum. The monitoring of bladder pressure and lung compliance and the incidence of iatrogenic pneumoperitoneum were retrospectively studied in 20 patients who underwent POEM between June 2013 and March 2015. The bladder pressure was measured using a Foley catheter. Abdominal distention was found in nine patients. The bladder pressure was significantly higher in the nine patients with the distention findings compared with patients without distention [7 (6–9) mmHg vs. 1 (0–2) mmHg; P < 0.05]; however, the decrease in dynamic lung compliance was not significantly different compared with patients without distention [− 7 (− 9.3 to − 5.1) vs. − 5 (− 10.2 to − 1.3) ml/cmH2O; P = 0.62]. Based on postoperative changes on CT scans; the following were the observations: pneumomediastinum (55%), minor pneumothorax (5%), pleural effusion (45%), atelectasis (15%), pneumoperitoneum (85%), and subcutaneous emphysema (15%). No significant clinical status was found among the patients postoperatively. Bladder pressure monitoring might be useful for detecting pneumoperitoneum during POEM..
16. Makoto Sasoh, Kenji Shigematsu, Emiko Toyama, Jingo Okawa, Ken Yamaura, Cesarean delivery for maternal mirror syndrome managed with general anesthesia
A case report, Anesthesia and Resuscitation, 54, 3-4, 39-41, 2018.12.
17. Ken Yamaura, Transition to an ere where we constantly aim for improvement of quality and efficiency in medicine, Japanese Journal of Anesthesiology, 67, 8, 2018.08.
18. Kiriko Takahashi, Chisato Umebayashi, Tomohiro Numata, Akira Honda, Jun Ichikawa, Yaopeng Hu, Ken Yamaura, Ryuji Inoue, TRPM7-mediated spontaneous Ca2+ entry regulates the proliferation and differentiation of human leukemia cell line K562, Physiological Reports, 10.14814/phy2.13796, 6, 14, 2018.07, Continuous Ca2+ influx is essential to maintain intracellular Ca2+ homeostasis and its dysregulation leads to a variety of cellular dysfunctions. In this study, we explored the functional roles of spontaneous Ca2+ influx for the proliferation and differentiation of a human erythromyeloid leukemia cell line K562. mRNA/protein expressions were assessed by the real-time RT-PCR, western blotting, and immunocytochemical staining. Intracellular Ca2+ concentration ([Ca2+]i) and ionic currents were measured by fluorescent imaging and patch clamping techniques, respectively. Cell counting/viability and colorimetric assays were applied to assess proliferation rate and hemoglobin synthesis, respectively. Elimination of extracellular Ca2+ decreased basal [Ca2+]i in proliferating K562 cells. Cation channel blockers such as SK&F96365, 2-APB, Gd3+, and FTY720 dose dependently decreased basal [Ca2+]i. A spontaneously active inward current (Ispont) contributive to basal [Ca2+]i was identified by the nystatin-perforated whole-cell recording. Ispont permeated Ca2+ comparably to Na+, and was greatly eliminated by siRNA targeting TRPM7, a melastatin member of the transient receptor potential (TRP) superfamily. Consistent with these findings, TRPM7 immune reactivity was detected by western blotting, and immunofluorescence representing TRPM7 was found localized to the K562 cell membrane. Strikingly, all these procedures, that is, Ca2+ removal, TRPM7 blockers and siRNA-mediated TRPM7 knockdown significantly retarded the growth and suppressed hemin-induced γ-globin and hemoglobin syntheses in K562 cells, respectively, both of which appeared associated with the inhibition of ERK activation. These results collectively suggest that spontaneous Ca2+ influx through constitutively active TRPM7 channels may critically regulate both proliferative and erythroid differentiation potentials of K562 cells..
19. Akira Gohara, Sumi Okamatsu-Kifuji, Shinjiro Shono, Midoriko Higashi, Ken Yamaura, Ventricular tachycardia without preceding electrocardiogram change after hypertonic mannitol administration
a case report, JA Clinical Reports, 10.1186/s40981-018-0191-0, 4, 1, 54, 2018.07, BACKGROUND: Mannitol is widely used during neurosurgery, but it has a serious complication including lethal arrhythmia due to mannitol-induced hyperkalemia.
CASE PRESENTATION: We report on a 62-year-old man scheduled for the clipping of an unruptured cerebral artery aneurysm. During surgery, approximately 20 min after the end of 200-mL 20% hypertonic mannitol administration, ventricular tachycardia (VT) occurred without preceding electrocardiogram (ECG) change, such as peaked T waves, and VT was recovered to sinus rhythm after chest compression. A potassium concentration after recovery from VT was 6.4 mEq/L, which was normalized by the administration of calcium gluconate, furosemide, and insulin with glucose.
CONCLUSIONS: Physicians must be aware that VT without preceding ECG change can occur after hypertonic mannitol administration..
20. Yutaka Kenmizaki, Takahisa Shiratake, Shigeto Kadekawa, Shiori Toda, Ken Yamaura, Bilateral pneumothorax during laparoscopic distal gastrectomy
A case report, Japanese Journal of Anesthesiology, 67, 5, 522-524, 2018.05, A 69-year-old man was scheduled for laparoscopic distal gastrectomy. He had pulmonary emphysema and a smoking history. Ninety eight minutes after the beginning of CO2 insufflation (10 mmHg), SpO2 decreased from 99 to 95%, EtCO2 increased from 35 to 39 mmHg While I investigated its cause, SPO2 decreased to 94% (FIO21.0), EtCO2 increased to 59 mmHg. Intraoperative chest X-ray showed bilateral pneumothorax without pneumomediastinum and subcutaneous emphysema Discussing with surgeons, we judged that the continuation of the pneumoperitonium was high-risk and performed open distal gastrectomy. Because it was both side pneumothorax and he was complicated with pulmonary emphysema After the end of the surgery, chest X-ray revealed complete resolution of pneumothoraces. The patient was moved to a general ward after tracheal extubation. As a cause of pneumothorax, the carbon dioxide inflow from the diaphragmatic weak part was suspected. Because it is hard to notice a decrease in pulmonary compliance during pressure controlled ventilatioa the appropriate alarm setting of a tidal volume is necessary..
21. Seiko Sato, Mariko Kaku, Ken Yamaura, Comparison of patient-controlled epidural analgesia and intravenous patient-controlled analgesia for postoperative pain in pediatric patients undergoing nuss procedure, Japanese Journal of Anesthesiology, 67, 4, 365-369, 2018.04, Background: Nuss procedure is a severely painful procedure for correcting pectus excavatum, and we conducted a retrospective comparison of patient-controlled epidural anesthesia (PCEA) and intravenous patient-controlled analgesia (IVPCA). Methods: The subjects were 26 pediatric patients aged between 5 to 15 years undergoing the Nuss procedure for pectus excavatum. Pain management was compared in patients with two groups: PCEA and IVPCA. Data collection included patient age and sex, body length, body weight, pain score, surgery/anesthesia times, the length of hospital stays after surgery, the use time of PCA, the rescue dose of analgesic drug, and complications. Results: Age, body length, body weight duration of anesthesia, length of hospital stays after surgery and time of PCA were significantly lower in IVPCA groups than in PCEA. There was no significant difference regarding the rescue dose of analgesic drug. Conclusions: The analgesic effect was not different between PCEA and IVPCA, and IVPCA may be better choice for anesthesiologist who do not have much experience of thoracic epidural anesthesia in children. The management of PONV and multimodal analgesia are needed..
22. Yuri Imakiire, Tomoaki Yanaru, Hitomi Kumano, Erisa Nakamori, Ken Yamaura, Malposition of peripherally inserted central catheter into the right inferior thyroid vein
A case report, American Journal of Case Reports, 10.12659/AJCR.908636, 19, 491-493, 2018.04, Objective: Unusual or unexpected effect of treatment Background: A peripherally inserted central catheter (PICC) causes few serious complications but can be malpositioned. To avoid malpositioning, ultrasound guidance is widely used. Here, we report the case of a patient who received a PICC that was inserted under ultrasound guidance, but the catheter tip accidentally entered the right inferior thyroid vein. Case Report: A 58-year-old woman was scheduled for reconstructive mammoplasty. After general anesthesia, a PICC was inserted via the right basilic vein. The PICC was inserted under guidance using a portable ultrasound machine with a high-frequency linear transducer. The tip of the guide wire and catheter were confirmed by ultrasound to be in the right subclavian vein, not in the right internal jugular vein, during insertion. However, the chest X-ray performed after the PICC insertion showed that the catheter had moved into the right inferior thyroid vein. Conclusions: Malpositioning of a PICC can occur into any small vein. Ultrasound should be used not only to avoid malpositioning into the IJV, but also to confirm the proper position of the catheter tip during PICC insertion..
23. T. Shimauchi, K. Yamaura, M. Higashi, K. Abe, T. Yoshizumi, S. Hoka, Fibrinolysis in Living Donor Liver Transplantation Recipients Evaluated Using Thromboelastometry
Impact on Mortality, Transplantation Proceedings, 10.1016/j.transproceed.2017.09.025, 49, 9, 2117-2121, 2017.11, Background Inadequate hemostasis during living donor liver transplantation (LDLT) is mainly due to coagulopathy but may also include fibrinolysis. The purpose of this study was to determine the incidence of fibrinolysis and assess its relevance to mortality in LDLT. Methods The incidence and prognosis of fibrinolysis were retrospectively studied in 76 patients who underwent LDLT between April 2010 and February 2013. Fibrinolysis was evaluated and defined by maximum lysis (ML) >15% within a 60-minute run time using thromboelastometry (ROTEM). Results Fibrinolysis was observed in 19 of the 76 (25%) patients before the anhepatic (pre-anhepatic) phase and was developed in 24 (32%) patients during and after the anhepatic (post-anhepatic) phase. In these 43 patients who had fibrinolysis, spontaneous recovery occurred in 29 patients (73%) within 3 hours after reperfusion of the liver graft. Recovery with tranexamic acid was noted in 2 patients with fibrinolysis in the post-anhepatic phase. Thrombosis in the portal vein and liver artery was noted in 14 patients, and the incidence was significantly greater in patients with post-anhepatic fibrinolysis than in those with pre-anhepatic fibrinolysis (P =.0017). Fibrinolysis that developed in the pre-anhepatic phase was associated with increased 30-day and 6-month mortalities (P =.0003 and.0026, respectively). Conclusions Fibrinolysis existed and developed in a large percentage of patients during LDLT. Thrombosis in the portal vein and hepatic artery was more common in patients with fibrinolysis in the post-anhepatic phase. Fibrinolysis that developed in the pre-anhepatic phase was associated with increased 30-day and 6-month mortalities..
24. Kazunori Hirota, Kazuhiko Hirata, Shiho Shibata, Kenji Shigematsu, Kazuo Higa, Ken Yamaura, Risk Vessels of Retropharyngeal Hematoma during Stellate Ganglion Block, Regional Anesthesia and Pain Medicine, 10.1097/AAP.0000000000000644, 42, 6, 778-781, 2017.11, Background and Objective Bleeding into the retropharyngeal space is a potential complication in stellate ganglion block (SGB). Retropharyngeal hematoma formation is considered to be due to damage of small arteries in the region, although only scanty details of the region are available. The aim of this study was to map the risk blood vessels in the retropharyngeal space to avoid accidental damage during SGB. Methods Contrast-enhanced 3-dimensional computed tomography images performed on 80 patients were reanalyzed retrospectively to construct detailed map of cervical blood vessels that are prone to damage and bleeding during SGB. Results Of the 160 bilateral necks, 6 (3.8%) and 82 (51.3%) small arteries were identified in the medial portions of the ventral surface of the transverse processes of the sixth and seventh cervical vertebrae, respectively. In particular, 5 of the 6 small arteries detected in the medial portion of the ventral surface of the transverse process of the sixth cervical vertebra were the inferior thyroid artery (ITA). Of the 160 vertebral arteries, 2 arteries were missing, 4 (2.5%) entered the transverse foramen of the fifth cervical vertebra, whereas 1 artery (0.6%) entered the transverse foramen of the fourth cervical vertebra. Conclusions Three-dimensional computed tomography identified the ITA in the medial portion of the ventral surface of the transverse process of the sixth cervical vertebra. The risk vessels of retropharyngeal hematoma during SGB could include the ITA..
25. Go Kusumoto, Kenji Shigematsu, Kouhei Iwashita, Kenji Tominaga, Takaaki Totoki, Ken Yamaura, Association between preoperative cardiac left ventricular dysfunction and perioperative intraaortic balloon pump in patients undergoing Off-Pump coronary artery bypass surgery, Heart Surgery Forum, 10.1532/hsf.1808, 20, 4, E147-E152, 2017.08, Background: Prophylactic use of intraaortic balloon pump (IABP) reduces hospital mortality in patients with left ventricular (LV) systolic dysfunction undergoing coronary artery bypass surgery (CABG); however, its association in patients with LV diastolic dysfunction is unclear. This retrospective study investigated the association between preoperative LV function and perioperative use of IABP in patients undergoing off-pump CABG (OPCAB) at a university hospital. Methods: 100 consecutive patients who underwent OPCAB between January 1, 2011 and August 31, 2014 were studied. Preoperative LV function was categorized into four groups based on LV systolic and diastolic function determined with preoperative transthoracic echocardiography. The use of IABP was reviewed from medical records. The Mann-Whitney test, Pearson chi-square test, or Fisher exact test were used. Results: Patients were categorized into the following groups: normal LV function (n = 43), isolated LV systolic dysfunction (n = 13), isolated LV diastolic dysfunction (n = 21), and combined LV systolic and diastolic dysfunction (n = 14). Intraoperative IABP use was significantly more frequent in patients with isolated LV systolic dysfunction, isolated LV diastolic dysfunction, and combined LV systolic and diastolic dysfunction than in those with normal LV function (P < .05). Furthermore, IABP was used more frequently in patients who developed combined LV systolic and diastolic dysfunction postoperatively (P < .05). Conclusion: Not only the presence of preoperative systolic dysfunction but also LV diastolic dysfunction in the presence of normal LV systolic function were associated with increased use of IABP during and after OPCAB..
26. Seiko Sato, Erisa Nakamori, Go Kusumoto, Kenji Shigematsu, Ken Yamaura, Neurally Mediated Syncope During Cesarean Delivery
A Case Report, A & A case reports, 10.1213/XAA.0000000000000440, 8, 5, 96-99, 2017.03, A 28-year-old woman with preeclampsia at 32 weeks of gestation underwent a cesarean delivery under spinal anesthesia. Administration of nitroglycerin at 200 μg to relax uterine smooth muscles and the application of fundal pressure led to severe bradycardia and loss of consciousness, followed by cardiac arrest. Delivery was completed immediately and recovery was achieved 10 seconds later following cardiopulmonary resuscitation. Neurally mediated syncope was considered the cause of cardiac arrest. Anesthetists should be aware of the potential risk during cesarean delivery following the administration of nitroglycerin, fundal pressure, regional anesthesia, and hypovolemia because of preeclampsia..
27. Isao Haraga, Shintaro Abe, Shiro Jimi, Fumiaki Kiyomi, Ken Yamaura, Increased biofilm formation ability and accelerated transport of Staphylococcus aureus along a catheter during reciprocal movements, Journal of Microbiological Methods, 10.1016/j.mimet.2016.11.003, 132, 63-68, 2017.01, Staphylococcus spp. is a major cause of device-related infections. However, the mechanisms of deep-tissue infection by staphylococci from the skin surface remain unclear. We performed in vitro experiments to determine how staphylococci are transferred from the surface to the deeper layers of agar along the catheter for different strains of Staphylococcus aureus with respect to bacterial concentrations, catheter movements, and biofilm formation. We found that when 5-mm reciprocal movements of the catheter were repeated every 8 h, all catheter samples of S. aureus penetrated the typical distance of 50 mm from the skin to the epidural space. The number of reciprocal catheter movements and the depth of bacterial growth were correlated. A greater regression coefficient for different strains implied faster bacterial growth. Enhanced biofilm formation by different strains implied larger regression coefficients. Increased biofilm formation ability may accelerate S. aureus transport along a catheter due to physical movements by patients..
28. Yamashita K, Shiwaku H, Ohmiya T, Shimaoka H, Okada H, Nakashima R, Beppu R, Kato D, Sasaki T, Hoshino S, Nimura S, Yamaura K, Yamashita Y, Efficacy and safety of endoscopic submucosal dissection under general anesthesia, JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, 31, 349-349, 2016.11.
29. Matsushita K, Yamaura K, Karashima Y, Akiyoshi K, Hoka S, Differences in anatomical relationship between vertebral artery and internal jugular vein in children and adults measured by ultrasonography., J Clin Monit Comput, 10.1007/s10877-015-9705-8, 30, 2, 221-225, J Clin Monit Comput 30:221-225, 2016, 2016.04.
30. Haraga I, Higa K, Abe S, Yamaura K, A novel model of epidural catheter-related infection: the importance of repeated catheter movements., Journal of Japan Society of Pain Clinicians, 23, 1, 1-7, 2016.03.
31. Makoto Sumie, Hiroaki Shiokawa, Ken Yamaura, Yuji Karashima, Sumio Hoka, Megumu Yoshimura, Direct effect of remifentanil and glycine contained in Ultiva® on nociceptive transmission in the spinal cord
In vivo and slice patch clamp analyses, PloS one, 10.1371/journal.pone.0147339, 11, 1, 2016.01, Background: Ultiva® is commonly administered intravenously for analgesia during general anaesthesia and its main constituent remifentanil is an ultra-short-acting μ-opioid receptor agonist. Ultiva® is not approved for epidural or intrathecal use in clinical practice. Previous studies have reported that Ultiva® provokes opioid-induced hyperalgesia by interacting with spinal dorsal horn neurons. Ultiva® contains glycine, an inhibitory neurotransmitter but also an N-methyl-D-aspartate receptor co-activator. The presence of glycine in the formulation of Ultiva® potentially complicates its effects. We examined how Ultiva1 directly affects nociceptive transmission in the spinal cord. Methods: We made patch-clamp recordings from substantia gelatinosa (SG) neurons in the adult rat spinal dorsal horn in vivo and in spinal cord slices. We perfused Ultiva® onto the SG neurons and analysed its effects on the membrane potentials and synaptic responses activated by noxious mechanical stimuli. Results: Bath application of Ultiva® hyperpolarized membrane potentials under current-clamp conditions and produced an outward current under voltage-clamp conditions. A barrage of excitatory postsynaptic currents (EPSCs) evoked by the stimuli was suppressed by Ultiva®. Miniature EPSCs (mEPSCs) were depressed in frequency but not amplitude. Ultiva®-induced outward currents and suppression of mEPSCs were not inhibited by the μ-opioid receptor antagonist naloxone, but were inhibited by the glycine receptor antagonist strychnine. The Ultiva®-induced currents demonstrated a specific equilibrium potential similar to glycine. Conclusions: We found that intrathecal administration of Ultiva1 to SG neurons hyperpolarized membrane potentials and depressed presynaptic glutamate release predominantly through the activation of glycine receptors. No Ultiva1-induced excitatory effects were observed in SG neurons. Our results suggest different analgesic mechanisms of Ultiva® between intrathecal and intravenous administrations..
32. Shiho Shibata, Eisuke Shono, Emi Nishimagi, Ken Yamaura, A patient with urinary tract tuberculosis during treatment with etanercept, American Journal of Case Reports, 10.12659/AJCR.893416, 16, 341-346, 2015.06, Objective: Diagnostic/therapeutic accidents Background: Tumor necrosis factor (TNF)-a inhibitors are widely used for rheumatoid arthritis (RA). However, there are several risks to use TNFa inhibitors. Given the properties of TNF-a inhibitors, prevention and early detection of tuberculosis (TB) are especially important. Even among TNF-a inhibitors, the risk of TB infection differs according to each drug. The incidence of TB is lowest with etanercept (ETN). We present a case of urinary tract TB during treatment with ETN. Case Report: A 58-year-old woman was receiving ETN for RA. Before starting ETN, isoniazid (INH) prophylaxis was started. RA was well controlled by ETN. However, 32 months after starting ETN, she noticed urinary frequency and a sensation of residual urine. The diagnosis was elusive, and it took 3 months until urinary tract TB was finally diagnosed. The TB resolved with antituberculosis medication, but RA disease activity flared up after ETN was discontinued. ETN was resumed with careful monitoring for TB recurrence. After resuming ETN, the RA was again well controlled, with no recurrence of TB. Conclusions: Patients should be monitored for development of TB during ETN treatment, but ETN can be used safely with careful management..
33. Midoriko Higashi, Ken Yamaura, Yukie Matsubara, Takuya Fukudome, Sumio Hoka, In-line pressure within a HOTLINE® Fluid Warmer, under various flow conditions, Journal of Clinical Monitoring and Computing, 10.1007/s10877-014-9605-3, 29, 2, 301-305, 2015.04, Roller pump infusion devices are widely used for rapid infusion, and may be combined with separate warming devices. There may be instances however, where the pressures generated by the roller pump may not be compatible with the warming device. We assessed a commonly used roller pump in combination with a HOTLINE® Fluid Warmer, and found that it could generate pressures exceeding the HOTLINE® manufacturers specifications. This was of concern because the HOTLINE® manufacturer guideline states that not for use with pressure devices generating over 300 mmHg. Pressure greater than 300 mmHg may compromise the integrity of the HOTLINE® Fluid Warming Set. The aim of this study was to compare in-line pressure within a HOTLINE® Fluid Warmer at different infusion rates of a roller pump using various sizes of intravenous cannulae. The rapid infusion system comprised a 500 mL-normal saline bag, roller pump type infusion device, HOTLINE® Fluid Warmer (blood and fluid warmer system), and six different sizes of intravenous cannulae. In-line pressure was measured proximal to the HOTLINE® (pre-warmer) and proximal to the cannula (post-warmer), at flow rate of 50–160 mL/min. The in-line pressures increased significantly with increasing flow rate. The pre-warmer pressures exceeded 300 mmHg when the flow rate was ≥120 mL/min with 20-gauge, 48 mm length cannula, 130 with 20-gauge, 25 mm cannula, and 160 mL/min with 18-gauge, 48 mm cannula. However, they were <300 mmHg at any flow rates with 18-gauge, 30 mm cannula and 16-gauge cannulae. The post-warmer pressures exceeded 300 mmHg at the flow rate of 140 mL/min with 20-gauge, 48 mm cannula, and 160 mL/min with 20-gauge, 25 mm cannula, while they were <300 mmHg at any flow rates with 18 and 16-gauge cannulae. The in-line pressure within a HOTLINE® could exceed 300 mmHg, depending on the flow rate and size and length of cannula. It is important to pay attention to the size and length of cannulae and flow rate to keep the maximum in-line pressure <300 mmHg when a roller pump type infusion device is used..
34. Ken Yamaura, Noriko Nanishi, Midoriko Higashi, Sumio Hoka, Effects of thermoregulatory vasoconstriction on pulse hemoglobin measurements using a co-oximeter in patients undergoing surgery, Journal of Clinical Anesthesia, 10.1016/j.jclinane.2014.04.012, 26, 8, 643-647, 2014.12, Study Objective: To validate intraoperative pulse hemoglobin (SpHb) measurements in anesthetized patients with large forearm temperature - fingertip temperature gradients. Design: prospective and observational study. Setting: Operating room of a university hospital. Patients: 28 patients undergoing surgery during general anesthesia, requiring arterial blood withdrawal. Interventions: Radial arterial blood pressure, forearm and fingertip skin surface temperatures, and SpHb were monitored. Measurements: Paired SpHb and arterial hemoglobin (Hb) measurements at different skin-surface temperature gradients. Main Results: A total of 175 paired SpHb and arterial Hb measurements were analyzed. The mean SpHb to arterial Hb differences in each group were 0.33 ± 1.41 g/dL in the < 1°C group of the forearm temperature - fingertip temperature gradient, -0.31 ± 1.24 g/dL in the 1 - 2°C group, - 0.59 ± 1.11 g/dL in the 2 - 3°C group, and - 0.53 ± 0.87 g/dL in the > 3°C group (P < 0.05). The percentage of nonmeasurable SpHb due to low perfusion state was 0% (0 of 115 paired measurements) in the < 1°C group, 6.7% (2 of 30 pairs) in the 1 - 2°C group, 16.7% (3 of 18 pairs) in the 2 - 3°C group, and 66.7% (8 of 12 pairs) in the > 3°C group. Conclusion: SpHb measured at fingertip was significantly affected by the perfusion state, with lower perfusion associated with lower SpHb. Thermoregulatory vasoconstriction affects measurement of SpHb..
35. Tsukasa Shimauchi, Ken Yamaura, Sayaka Sugibe, Sumio Hoka, Usefulness of sugammadex in a patient with Becker muscular dystrophy and dilated cardiomyopathy, Acta Anaesthesiologica Taiwanica, 10.1016/j.aat.2014.02.005, 52, 3, 146-148, 2014.09, A 54-year-old patient with Becker muscular dystrophy and dilated cardiomyopathy underwent laparoscopic cholecystectomy under total intravenous anesthesia. Muscle relaxation was induced by rocuronium (0.4 mg/kg body weight) under train-of-four (TOF) ratio monitoring. The TOF ratio was 0 at intubation, and 0.2 at the end of surgery. Residual muscle relaxant activity was successfully reversed by sugammadex (2 mg/kg body weight) without any hemodynamic adverse effects (TOF ratio 1.0 at extubation). The clinical and hemodynamic findings suggest that sugammadex can be safely used in patients with Becker muscular dystrophy and dilated cardiomyopathy..
36. Maiko Tanaka, Ken Yamaura, Midoriko Higashi, Sumio Hoka, Leakage of sevoflurane from vaporizer detected by air monitoring system
A case report, Journal of Clinical Monitoring and Computing, 10.1007/s10877-013-9479-9, 27, 6, 629-631, 2013.12, Leakage of inhalational anesthetic gases is an important issue not only to staff health but awareness during general anesthesia. After inhalation of sevoflurane commenced, the audible and visible alarm of our custom-made air monitoring system was activated. The system measured 2-4 ppm of sevoflurane. A thorough search failed to identify the source of the leak. After changing inhalational anesthesia to intravenous anesthesia, the concentration of sevoflurane decreased immediately to zero. The filling level on the vaporizer decreased faster than usual. A thorough check of the vaporizer after surgery identified a worn down seal in the filling device of the vaporizer..
37. M. Higashi, K. Yamaura, Mizuko Ikeda, Tsukasa Shimauchi, H. Saiki, Sumio Hoka, Diastolic dysfunction of the left ventricle is associated with pulmonary edema after renal transplantation, Acta Anaesthesiologica Scandinavica, 10.1111/aas.12168, 57, 9, 1154-1160, 2013.10, Background Post-operative pulmonary complications are associated with high mortality and graft loss in renal transplantation recipients. Left ventricular diastolic dysfunction is not uncommon in patients with chronic renal failure, including those with preserved left ventricular systolic function. The purpose of this study was to determine the relationship between left ventricular diastolic dysfunction and incidence of post-operative pulmonary edema in renal transplantation recipients with preserved left ventricular systolic function. Methods Pre-operative left ventricular function and incidence of pulmonary edema were retrospectively studied in 209 patients who underwent living-donor renal transplantation between January 2010 and October 2012. Left ventricular systolic and diastolic functions were evaluated by ejection fraction and E/E' ratio, retrospectively, using transthoracic echocardiography. Pulmonary edema was defined by evidence of pulmonary congestion on the chest X-ray together with PaO2/FiO2 ratio < 300 mmHg. Results Eleven out of 190 (5.8%) renal transplantation patients with preserved left ventricular systolic function developed post-operative pulmonary edema. Patients with pulmonary edema had a significantly higher geometric mean (95% confidence interval) of E/E' ratio than those without pulmonary edema [17.8 (14.1-22.5) vs. 11.1 (10.6-11.7), P = 0.001]. Conclusion Pre-operative left ventricular diastolic dysfunction correlated with the development of post-operative pulmonary edema in renal transplantation recipients. Meticulous intraoperative volume therapy is important to avoid post-operative pulmonary edema in such patients..
38. Noriko Nanishi, Ken Yamaura, Matsushita Katsuyuki, Akiyoshi Kozaburo, Yuji Karashima, Midoriko Higashi, Sumio Hoka, Endovascular abdominal aortic aneurysm repair under general anesthesia does not decrease perioperative myocardial ischemic event compared with open repair. , OJAnes, 3, 84-89, 2013.06.
39. Shotaro Sakimura, Midoriko Higashi, Noriko Nanishi, Norimitsu Sugioka, Kazuhiro Sirouzu, Ken Yamaura, Sumio Hoka, Anesthetic management of a parturient with congenital afibrinogenemia undergoing cesarean section, Japanese Journal of Anesthesiology, 61, 12, 1369-1372, 2012.12, A 29-year-old parturient with congenital afibrinogenemia was scheduled to receive cesarean section at 38 weeks 2 days of gestation. Due to the bleeding tendency by her abnormality of fibrinogen and afibrinogenemia, general anesthesia was chosen. In addition to routine administration of fibrinogen, perioperative supplementation of fibrinogen with the meticulous evaluation of the coagulation and fibrinolysis status using rotation thromboelastometry (ROTEM®) enabled the patient to deliver a healthy baby without any hematological complications. The ROTEM® was a useful device to check coagulopathy and fibrinolysis in this patient..
40. Kengo Hayamizu, Ken Yamaura, Mariko Hayamizu, Tadashi Kandabashi, Sumio Hoka, Anesthetic management of a patient with Klippel-Trenaunay syndrome for caesarean section, Japanese Journal of Anesthesiology, 61, 8, 893-895, 2012.08, Klippel-Trenaunay syndrome (KTS) is characterized by capillary and venous malformation and hypertrophy of bone and soft tissues. A 29-year-old Primigravida, who had been diagnosed of KTS by her hemangiomas and varicosities in the right leg, pubic area, rectum, vagina and lower abdominal area, was scheduled to receive caesarean section at 37 weeks gestation because vaginal delivery might cause hemorrhagic complications and extension of the venous lesions. Regional anesthesia was avoided because of the possible injuries of unknown venous malformations or varicose veins in the epidural or spinal space. The cesarean section was performed under general anesthesia uneventfully and an infant was delivered normally. There were no complications such as massive hemorrhage, disseminated intravascular coagulation and deep venous thrombosis in the perioperative period. Careful anesthetic considerations for the prevention of hemorrhagic and thrombotic complications are necessary for cesarean section in a patient with KTS..
41. Makoto Sumie, Kouhei Toyama, Tomoka Yokoo-Matsuoka, Ken Yamaura, Sumio Hoka, Keiko Morikawa, Chihiro Takamatsu, Inadvertent bleeding in an infant after inguinal hernioplasty leads to diagnosis of hemophilia B, Journal of Anesthesia, 10.1007/s00540-011-1290-5, 26, 2, 299-300, 2012.04.
42. kozaburo akiyoshi, Tadashi Kandabashi, Junko Kaji, Ken Yamaura, Hayashi Yoshimura, Kazuo Irita, Sumio Hoka, Accuracy of arterial pressure waveform analysis for cardiac output measurement in comparison with thermodilution methods in patients undergoing living donor liver transplantation, Journal of Anesthesia, 10.1007/s00540-010-1087-y, 25, 2, 178-183, 2011.04, Purpose The aim of this study was to assess the accuracy of the first and third versions of arterial pressure waveform ardiac output (APCOv.1.0 and APCOv.3.0) measurements in comparison with thermodilution methods in patients undergoing living donor liver transplantation. Methods Twenty patients were anesthetized and mechanically ventilated. A radial arterial line was connected to a dedicated transducer for the APCO evaluation (FloTracTM). A pulmonary artery catheter was placed and connected to a computer system (VigilanceTM) to measure intermittent thermodilution cardiac output (COTD) and continuous cardiac output (CCO). Results A total of 138 measurements were analyzed. Bland-Altman analysis showed that the mean biases for COTD-APCOv.3.0, CO TD-APCOv.1.0, and COTD-CCO were 0.89, 1.73, and -0.79 L/min, and the adjusted percentage errors were 37.5, 30.3, and 43%, respectively. While the variance for COTD-APCOv.3.0 was greater, the accuracy bias) improved by 0.8 L/min as compared with CO TD-APCOv.1.0. The difference COTD-APCO v.3.0 became apparent when systemic vascular resistance was lower than 1000 dyne 9 s/cm5 , especially below 700 dyne 9 s/cm 5. Conclusion These data suggest that the accuracy of APCO v.3.0 has improved compared to APCOv.1.0 due to the updated algorithm, but additional improvements should be evaluated, especially in patients undergoing living donor liver transplantation with low systemic vascular resistance..
43. Yoshiro Sakaguchi, Sayaka Osawa, Kentaro Tokuda, Kohei Toyama, Chihiro Takamatsu, Y Matsuoka, Ken Yamaura, Sumio Hoka, Anaphylactic shock during anesthesia in a child undergoing emergent cadaver donor renal transplantation., 日本小児麻酔学会誌 Clinical Pediatric Anesthesia, 16, 1, 157-159, case report, 2010.12.
44. Sayaka Osawa, Ken Yamaura, Akiyoshi Kozaburo, sakaguchi yoshiro, EIICHIRO NODA, Sumio Hoka, A gastric perforation after transesophageal echocardiography in an elderly patient undergoing cardiac surgery., 循環制御 Circulation Control, 31, 3, 193-195, case report, 2010.12.
45. Nakahara E, Nara Y, Ozawa A, Toda M, Okamoto H, Yamaura K, Hoka S., The Effect of Synthetic Agonists and Antagonists of Cannabinoid Receptors on Migration of Neutrophils Elicited by Leukotrience B4 in the Microvasculature of Hamster Cheek Pouch, 循環制御, 31, 3, 202-207, 2010.12.
46. Junko Kaji, Midoriko Higashi, Yoshiro Sakaguchi, Jun Maki, Tetsuya Kai, Ken Yamaura, Sumio Hoka, Fiberoptic intubation using two tracheal tubes for a child with goldenhar syndrome, Japanese Journal of Anesthesiology, 59, 12, 1526-1528, 2010.12, Goldenhar syndrome is associated with difficult airway due to the characteristic craniofacial anomalies such as hypoplasia of the mandible and molar bones. We present our method of fiberoptic intubation using two tracheal tubes for a girl with Goldenhar syndrome undergoing cochlear implant surgery. She had received general anesthesia for dental treatment one year before, but the treatment had been cancelled because of the failure of tracheal intubation. We induced anesthesia for her with inhalation of sevoflurane and nitrous oxide. After obtaining a stable anesthetic level, we inserted two tracheal tubes from the right and left nostrils, one for a tracheal tube and the other for a nasopharyngeal airway. During the procedure, the fiberscope was advanced through the tracheal tube with a slit connector, and her ventilation was assisted through the nasopharyngeal airway with her mouth closed by a tape to avoid a leak of ventilating gas. Using this two-tube method, we successfully intubated the trachea of a patient Goldenhar syndrome..
47. Yamaura K, Kai T, Kandabashi T, Akiyoshi K, Sakaguchi Y, Hoka S, The Accuracy of Continuous Thermodilution Method in Comparison with Bolus Cardiac Output Measurement Using Room Temperature Versus Cold Injectates in Cardiac Surgical Patients, 循環制御, 31, 1, 39-43, 2010.07.
48. Shoko Nakayama, Ken Yamaura, Noriko Nanishi, Tadashi Kandabashi, Sumio Hoka, Sedated awake intubation using Pentax-AWS® in a patient with Treacher-Collins syndrome, Anesthesia and Resuscitation, 46, 2, 31-33, 2010.06, A 23 year-old man with a typical difficult airway due to Treacher-Collins syndrome was scheduled for elective tympanoplasty. His past anesthesia record revealed a history of difficult mask ventilation and several unsuccessful attempts at orotracheal intubation, with laryngeal evaluation of Cormack and Lehane grade 4. We successfully performed sedated awake intubation of the orotrachea using the Pentax AWS®. Sedated awake intubation using Pentax-AWS® is useful in patients with a difficult airway..
49. Debebe Gebremedhin, Ken Yamaura, David R. Harder, Role of 20-HETE in the hypoxia-induced activation of Ca2+- activated K+ channel currents in rat cerebral arterial muscle cells, American Journal of Physiology - Heart and Circulatory Physiology, 10.1152/ajpheart.01416.2006, 294, 1, H107-H120, 2008.01, The mechanism of sensing hypoxia and hypoxia-induced activation of cerebral arterial Ca2+-activated K+ (KCa) channel currents and vasodilation is not known. We investigated the roles of the cytochrome P-450 4A (CYP 4A) ω-hydroxylase metabolite of arachidonic acid, 20-hydroxyeicosatetraenoic acid (20-HETE), and generation of superoxide in the hypoxia-evoked activation of the KCa channel current in rat cerebral arterial muscle cells (CAMCs) and cerebral vasodilation. Patch-clamp analysis of K+ channel current identified a voltage- and Ca2+- dependent 238 ± 21-pS unitary K+ currents that are inhibitable by tetraethylammonium (TEA, 1 mM) or iberiotoxin (100 nM). Hypoxia (<2% O2) reversibly enhanced the open-state probability (NPo) of the 238-pS unitary KCa current in cell-attached patches. This effect of hypoxia was not observed on unitary KCa currents recorded from either excised inside-out or outside-out membrane patches. Inhibition of CYP 4A ω-hydroxylase activity increased the NPo of K Ca single-channel current. Hypoxia reduced the basal endogenous level of 20-HETE by 47 ± 3% as well as catalytic formation of 20-HETE in cerebral arterial muscle homogenates as determined by liquid chromatography-mass spectrometry analysis. The concentration of authentic 20-HETE was reduced when incubated with the superoxide donor KO2. Exogenous 20-HETE (100 nM) attenuated the hypoxia-induced activation of the KCa current in CAMCs. Hypoxia did not augment the increase in NPo of KCa channel current induced by suicide inhibition of endogenous CYP 4A ω-hydroxylase activity with 17-octadecynoic acid. In pressure (80 mmHg)-constricted cerebral arterial segments, hypoxia induced dilation that was partly attenuated by 20-HETE or by the KCa channel blocker TEA. Exposure to hypoxia caused the generation of intracellular superoxide as evidenced by intense staining of arterial muscle with the fluorescent probe hydroethidine, by quantitation using fluorescent HPLC analysis, and by attenuation of the hypoxia-induced activation of the KCa channel current by superoxide dismutation. These results suggest that the exposure of CAMCs to hypoxia results in the generation of superoxide and reduction in endogenous level of 20-HETE that may account for the hypoxia-induced activation of arterial KCa channel currents and cerebral vasodilation..
50. Ken Yamaura, Kazuo Irita, Tadashi Kandabashi, Kohei Tohyama, Shosuke Takahashi, Evaluation of finger and forehead pulse oximeters during mild hypothermic cardiopulmonary bypass, Journal of Clinical Monitoring and Computing, 10.1007/s10877-007-9081-0, 21, 4, 249-252, 2007.08, Objective: The purpose of this study was to examine and compare the four combination of pulse oximeters (POs) and monitoring sites, the Nihon Kohden BSS-9800 (N), the Masimo SET Radical (M), the Nellcor N550 D-25 (N-D) and the Nellcor N550 Max-Fast (N-MF) in patients with peripheral hypoperfusion. Methods: About 20 adult patients undergoing cardiac surgery using mild hypothermic cardiopulmonary bypass (CPB) were studied prospectively. PO sensors were applied on fingers in N, M and N-D, while on the forehead in N-MF. Results: PO failure was defined as failure to show no SpO2 value or incorrect SpO2 values. PO failure occurred in 12 patients with N, ten patients with M, four patients with N-D and ten patients with N-MF, respectively (p < 0.05 N-D vs. N, M, N-MF). The duration of PO failure was 19+/-30% of aortic cross-clamping with N, 29 +/-33% with M, 10 +/-26% with N-D and 43 +/- 57% with N-MF, respectively (p < -0.05 N-D vs. M and N-MF). Conclusions: The results suggested that N-D is most useful among four combinations of POs and monitoring sites tested in this study for monitoring SpO2 during hypoperfusion. The superiority of N-MF during hypoperfusion was not evident in the present study..
51. Ken Yamaura, D. Gebremedhin, C. Zhang, J. Narayanan, K. Hoefert, E. R. Jacobs, R. C. Koehler, D. R. Harder, Contribution of epoxyeicosatrienoic acids to the hypoxia-induced activation of Ca2+-activated K+ channel current in cultured rat hippocampal astrocytes, Neuroscience, 10.1016/j.neuroscience.2006.08.021, 143, 3, 703-716, 2006.12, Brief hypoxia differentially regulates the activities of Ca2+-activated K+ channels (KCa) in a variety of cell types. We investigated the effects of hypoxia (<2% O2) on KCa channel currents and on the activities of cytochrome P450 2C11 epoxygenase (CYP epoxygenase) in cultured rat hippocampal astrocytes. Exposure of astrocytes to hypoxia enhanced macroscopic outward KCa current, increased the open state probability (NPo) of 71 pS and 161 pS single-channel KCa currents in cell-attached patches, but failed to increase the NPo of both the 71 pS and 161 pS KCa channel currents recorded from excised inside-out patches. The hypoxia-induced enhancement of macroscopic KCa current was attenuated by pretreatment with tetraethylammonium (TEA, 1 mM) or during recording using low-Ca2+ external bath solution. Exposure of astrocytes to hypoxia was associated with generation of superoxide as detected by staining of cells with the intracellular superoxide detection probe hydroethidine (HE), attenuation of the hypoxia-induced activation of unitary KCa channel currents by superoxide dismutation with tempol, and as quantitated by high-pressure liquid chromatography/fluorescence assay using HE as a probe. In cultured astrocytes in which endogenous CYP epoxygenase activity has been inhibited with either miconazole or N-methylsulfonyl-6-(2-propargyloxyphenyl) hexanamide (MSPPOH) hypoxia failed to increase the NPo of both the 71 pS and 161 pS KCa currents and generation of superoxide. Hypoxia increased the level of P450 epoxygenase protein and production of epoxyeicosatrienoic acids (EETs) from cultured astrocytes, as determined by immunohistochemical staining and LC/MS analysis, respectively. Exogenous 11,12-EET increased the NPo of both the 71 pS and 161 pS KCa single-channel currents only in cell-attached but not in excised inside-out patches of cultured astrocytes. These findings indicate that hypoxia enhances the activities of two types of unitary KCa currents in astrocytes by a mechanism that appears to involve CYP epoxygenase-dependent generation of superoxide and increased production or release of EETs..
52. Drazen Zagorac, Ken Yamaura, Cindy Zhang, Richard J. Roman, David R. Harder, The effect of superoxide anion on autoregulation of cerebral blood flow, Stroke, 10.1161/01.STR.0000189997.84161.95, 36, 12, 2589-2594, 2005.12, Background and Purpose - Recent studies have suggested that autoregulation of cerebral blood flow (CBF) is impaired after traumatic and ischemic brain injury. Given that the levels of superoxide anion (O2.-) are increased in these conditions, we postulate that O2.- contributes to the impairment of CBF autoregulation. Methods - CBF was monitored with laser Doppler flowmetry during increases in blood pressure. Results - During the control period, CBF was well autoregulated after the increase in mean arterial pressure (MAP) from 98±3 to 140±6 mm Hg. The autoregulation index (AI; ΔCBF/ΔMAP) averaged 0.25±0.02 (n=6). O2.- in the brain was then increased by subdural perfusion of xanthine/xanthine oxidase (different concentrations) and catalase. Low concentrations of O2.- decreased basal CBF by 10±1.6% but had no effect on autoregulation (AI, 0.19±0.02; n=6). Higher concentrations of O2.- (0.2 mmol/L xanthine and either 3 or 20 mU xanthine oxidase) increased basal CBF by 30±2% and 42±4%, respectively, and impaired autoregulation of CBF (AI, 0.55±0.03 and 0.76±0.02; n=6). Inclusion of superoxide dismutase in the O2.--generating system restored autoregulation (AI, 0.28±0.05; n=6). Neither inhibition of NO synthase nor the addition of deferioxamine had any effect on the ability of higher concentrations of O 2.- to impair autoregulation of CBF (AI, 0.65±0.07 and 0.72±0.05 respectively; n=6). O2.- also increased the activity of KCa channels in cerebral vascular smooth muscle cells (VSMCs; n=8). Conclusion - These results suggest that O 2.- increases basal CBF and impairs autoregulation of CBF, likely through the activation of KCa channels in cerebral VSMCs..
53. Ken Yamaura, Sumio Hoka, Hirotsugu Okamoto, Shosuke Takahashi, Noninvasive assessment of left ventricular pressure-area relationship using transesophageal echocardiography and tonometry during cardiac and abdominal aortic surgery, Journal of Anesthesia, 10.1007/s00540-004-0296-7, 19, 2, 106-111, 2005.05, Purpose: The purpose of this study was to noninvasively evaluate intraoperative left ventricular (LV) performance by an online pressure-area relationship using transesophageal echocardiography (TEE) and tonometry. Methods: In study 1, LV pressure with a micromanometer catheter, LV cross-sectional area with TEE, direct radial pressure, and tonometric arterial pressure were simultaneously recorded in 5 patients (10 measurements) undergoing cardiac surgery. End-systolic elastance (E′es) was determined from pressure-area loops during inferior vena caval (IVC) occlusion. In study 2, in 16 patients undergoing repair of abdominal aortic aneurysm, LV performance (E′es; effective arterial load, E′a, and LV end-diastolic area, LV-EDA) was examined by noninvasive assessment of pressure-area loops using TEE and tonometry at aortic cross-clamping and unclamping. Results: E′es by tonometric arterial pressure closely correlated with E′es by LV pressure (r = 0.92) in study 1. E′es at aortic clamping were not significantly different from those at unclamping. The clamping increased LV-EDA and E′a by approximately 13% and 44%, and the unclamping significantly decreased by 9% and 22%, respectively. Conclusion: Our results demonstrated that online tonometric arterial pressure and LV area measured by automated border detection (ABD) of TEE might be used to calculate E′es to estimate LV contractility and allow the estimation of LV performance during aortic clamping and unclamping..
54. Takashi Akata, Ken Yamaura, Tadashi Kandabashi, Shinya Sadamatsu, Shosuke Takahashi, Changes in body temperature during profound hypothermic cardiopulmonary bypass in adult patients undergoing aortic arch reconstruction, Journal of Anesthesia, 10.1007/s00540-003-0225-1, 18, 2, 73-81, 2004.08, Purpose. Our aim was to characterize changes in body temperatures during profound hypothermic cardiopulmonary bypass (CPB) conducted with the sternum opened. Methods. In ten adult patients who underwent profound hypothermic (<20°C) CPB for aortic arch reconstruction, pulmonary arterial temperature (PAT), nasopharyngeal temperature (NPT), forehead deep-tissue temperature (FHT), and urinary bladder temperature (UBT) were recorded every 1 min throughout the surgery. In addition, the CPB venous line temperature (CPBT), a reasonable indicator of mixed venous blood temperature during CPB and believed to best reflect core temperature during stabilized hypothermia on CPB, was recorded during the period of total CPB. Results. PAT began to change immediately after the start of cooling or rewarming, closely matching the CPBT (r = 0.98). During either situation, the other four temperatures lagged behind PAT (P < 0.05); however, NPT followed PAT more closely than the other three temperatures (P < 0.05). During stabilized hypothermia, PAT, NPT, and FHT, but not UBT, closely matched the CPBT, with gradients of less than 0.5°C. Conclusion. During induction of profound hypothermia and its reversal on total CPB with the heart in situ, a PA catheter thermistor, presumably because of its placement immediately behind the superior vena cava, would provide a reliable measure of the mixed venous blood temperature. During stabilized profound hypothermia, PAT, NPT, and FHT, but not UBT, serve as a reliable index of core temperature..
55. Yamaura K., Hoka S., Yoshimura J., Takahashi S., Preoperative non-invasive assessment of stress response to breath-holding test, 循環制御, 2004.03.
56. Ken Yamaura, Sumio Hoka, Hirotsugu Okamoto, Shosuke Takahashi, Quantitative Analysis of Left Ventricular Regional Wall Motion with Color Kinesis during Abdominal Aortic Cross-Clamping, Journal of Cardiothoracic and Vascular Anesthesia, 10.1053/j.jvca.2003.09.005, 17, 6, 703-708, 2003.12, Objectives: The authors aimed to establish a technique for quantitative analysis of regional wall motion abnormality (RWMA) using color kinesis (CK) of transesophageal echocardiography (TEE) in surgical patients. This technique was used to determine whether RWMAs develop de novo after infrarenal aortic cross-clamping in patients undergoing vascular surgery with a preoperative dipyridamole thallium stress test (DTST). Design: An observational study. Setting: University hospital. Participants: Thirty-eight patients undergoing infrarenal abdominal aortic aneurysm resection or aortofemoral bypass. Measurements and Main Results: CK images of the left ventricle (LV) were obtained from the midventricular transgastric short-axis view before and after infrarenal aortic cross-clamping using TEE and analyzed off-line using custom software. The predictive value of the category "reversible perfusion defect" (RD) was also estimated from DTST for predicting new RWMAs with CK. CK analysis is suitable for clinical use based on the comparison with conventional two-dimensional echocardiogram measurements and inter-observer variability. CK analysis showed all 7 patients with persistent perfusion defects on DTST had RWMAs. New RWMAs occurred in 2 of 9 patients with RD and in 2 of 15 patients with normal DTST, indicating that there was no significant difference between RD and normal DTST in the incidence of new RWMAs. Conclusions: A new method is available for clinical use, which is capable of visualizing RWMAs. These results suggest that new RWMAs introduced by aortic cross-clamping occur irrespective of the risk as assessed by preoperative DTST. CK with the new analysis method might be a useful tool to quantitatively evaluate RWMAs during surgery..
57. Debebe Gebremedhin, Ken Yamaura, Chenyang Zhang, Johan Bylund, Raymund C. Koehler, David R. Harder, Metabotropic glutamate receptor activation enhances the activities of two types of Ca2+-activated K+ channels in rat hippocampal astrocytes, Journal of Neuroscience, 23, 5, 1678-1687, 2003.03, The influence of activation of glutamate receptor (GluR) on outward K+ current in cultured neonate rat hippocampal astrocytes was investigated. Patch-clamp analysis of K+ channel currents in cultured astrocytes identified the existence of 71 ± 6 and 161 ± 11 pS single-channel K+ currents that were sensitive to changes in voltage and [Ca2+]i and blocked by external TEA but not by charybdotoxin, iberiotoxin, apamin, or 4-aminopyridine. Reverse transcriptase (RT)-PCR and Northern blot analysis revealed transcripts of the Ca2+-activated K+ channel (KCa) β4-subunit (β4) (KCNMB4) in cultured astrocytes. Expression of the metabotropic glutamate receptor (mGluR) subtypes mGluR1 and mGluR5 and the ionotropic glutamate receptor (iGluR) subtypes iGluR1 and iGluR4 were detected by RT-PCR and immunofluorescence analysis in cultured astrocytes. The mGluR agonists L-glutamate and quisqualate increased the open state probability (NPo) of the 71 and 161 pSK+ channel currents that were prevented by the mGluR receptor antagonists 1-aminoindan-1,5-dicarboxylic acid or L-(+)-2-amino-3-phosphonopropionic acid and not by the iGluR antagonists (+)-5-methyl-10,11-dihydro-5H-dibenzo [a,d] cyclohepten-5,10-imine maleate or CNQX. Activation of the two types of K+ channel currents by mGluR agonists was attenuated by pertussis toxin and by inhibition of phospholipase C (PLC) or cytochrome P450 arachidonate epoxygenase. These results indicate that brain astrocytes contain the KCNMB4 transcript and express two novel types of KCa channels that are gated by activation of a G-protein coupled metabotropic glutamate receptor functionally linked to PLC and cytochrome P450 arachidonate epoxygenase activity..
58. Kazumasa Matsuo, Takashi Akata, Ken Yamaura, Keiko Morikawa, Tadashi Kandabashi, Naoyuki Ueda, Kohei Tohyama, Shosuke Takahashi, Intraoperative monitoring of pressure within saline-filled, endotracheal tube cuff in adult patients undergoing CO2 laser laryngomicrosurgery, Japanese Journal of Anesthesiology, 51, 5, 482-488, 2002.06, In laser laryngomicrosurgery, saline is injected into the endotracheal tube cuff to prevent airway fire. Utilizing regression analyses, we investigated the relation between the saline volume required to obtain optimal intracuff pressure and tracheal diameters in patients undergoing laser laryngomicrosurgery as well as in model tracheas. Although excellent linear correlations were found between the saline volume and the diameter of model tracheas, no significant linear or non-linear correlation was found between the saline volume and the patient's tracheal diameter. In the model tracheas, a rate of rise in the intracuff pressure caused by increments in the injected volume was far steeper when saline was injected into the cuff than when air was injected into the cuff. Addition of only 0.2 ml saline could result in large (>50 mmHg) increases in the intracuff pressure. Also in patients, addition of 1 ml could result in notable (>50 mmHg) increases in the intracuff pressure. These results suggest that the saline volume necessary to obtain optimal intracuff pressure is difficult to be predicted from the patient's tracheal diameter, and that slight increases in the saline volume may cause excessive increases in the intracuff pressure. The intracuff pressure should be tightly monitored in patients undergoing laser laryngomicrosurgery..
59. Junko Murakami, Ken Yamaura, Takashi Akata, Shosuke Takahashi, Acute renal failure in an infant attributable to arterial cannula malposition during cardiopulmonary bypass via ministernotomy, Japanese Journal of Anesthesiology, 51, 3, 264-269, 2002.04, A 6-month-old female (4.9 kg) with multiple congenital heart lesions underwent intracardiac repair with the aid of cardiopulmonary bypass (CPB) through a lower half sternotomy. Aortic cannulation, venous cannulation, and cardioplegia cannula insertion were all accomplished through the ministernotomy. During the CPB, in spite of a high perfusion flow rate (182 ml · kg
· min
), the systemic arterial pressure was persistently low (mean values = 25-35 mmHg) and the urine output was greatly reduced ( -1
). In addition, inappropriate increases in the arterial inflow line pressure were recognized. Since abutment of the cannula tip against the aortic intima was suspected, several attempts were made to correct its malpositioning. During the CPB, hemolysis was also found in the mixed venous blood. Since the oliguria and resultant hyperkalemia persisted after weaning from the CPB, peritoneal dialysis was introduced immediately after the surgery. Her renal function gradually recovered postoperatively, and she was finally weaned from the peritoneal dialysis on the 13
postoperative day. Although the ministernotomy has been proposed to be a safe approach for most of cardiac surgeries, it appears to increase the risk for arterial cannula malposition as compared to the standard full-length sternotomy in small pediatric patients..
60. Ken Yamaura, kozaburo akiyoshi, K. Irita, S. Takahashi, Effect of coronary artery bypass grafting with gastroepiploic artery on gastric intramucosal pH and systemic inflammation, Journal of Cardiovascular Surgery, 42, 6, 723-729, 2001.12, Background. The purpose of this study was to investigate the effect of coronary arterial bypass grafting (CABG) with gastroepiloic artery (GEA) on gastric intramucosal pH and systemic inflammation. Methods. Design: retrospective study. Setting: University hospital. Participants: 22 patients under-went CABG. Investigations: the GEA group (n=13) received CABG with the GEA graft. The non-GEA group (n=9) received conventional CABG without the GEA graft. Measurements: gastric intramucosal pH (pHi) and carbon dioxide tension (PrCO2) were assessed by capnometric air tonometry. The difference between PrCO2 and PaCO2, PCO2-gap, was also determined. Systemic inflammatory responses were evaluated by serum interleukin-6 (IL-6) and leucocyte counts. Hemodynamics, oxygen delivery index (DO2I) and uptake index (VO2I) were monitored with catheters in the radial and pulmonary arteries (thermodilution). Results. The duration of aortic cross-clamping and cardiopulmonary bypass was similar in both groups. Both groups did not show any significant difference in gastric pHi, PCO2-gap, systemic inflammation and hemodynamics. Conclusions. Our findings suggest that CABG using the GEA graft does not disturb gastric mucosal perfusion, and that laparotomy for the GEA graft does not aggravate systemic oxygen demand-supply imbalance or systemic inflammatory responses induced by hypothermic CPB. CABG with the GEA graft does not seem to pose an additional risk and is a safe technique compared with conventional CABG with regard to pHi and systemic inflammation..
61. K. Yamaura, K. Akiyoshi, K. Irita, T. Taniyama, S. Takahashi, Effects of olprinone, a new phosphodiesterase inhibitor, on gastric intramucosal acidosis and systemic inflammatory responses following hypothermic cardiopulmonary bypass, Acta Anaesthesiologica Scandinavica, 10.1034/j.1399-6576.2001.045004427.x, 45, 4, 427-434, 2001.04, Background: Phosphodiesterase (PDE) III inhibitors have both an inotropic and a peripheral vasodilatory effect, and also inhibit the activation of macrophages. Thus a newly developed PDE III inhibitor, olprinone, could modify gastric intramucosal pH (pHi), systemic oxygen consumption, and systemic inflammatory responses in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). Methods: We studied 23 patients. In 15 patients, olprinone (0.1 or 0.2 μg · kg-1 · min-1) was administered from the commencement of CPB until their admission to the ICU. The other 8 patients received placebo. The pHi and regional CO2 tension (PrCO2) were assessed by a capnometric air tonometry. Systemic inflammatory responses were evaluated by serum interleukin-6 (IL-6), IL-10, and leucocyte counts. Results: The pHi and PCO2-gap, the difference between PrCO2 and arterial CO2 tension (PaCO2), showed a transient decrease and an increase after CPB, respectively. Although olprinone did not affect pHi, olprinone at 0.2 μg · kg-1 · min-1 significantly lessened post-CPB increase in PCO2-gap. Olprinone at 0.2 μg · kg-1 · min-1 significantly increased IL-10 and reduced the extent of leucocytosis, while it did not affect IL-6 levels. At the same dosage, olprinone also lessened the surge in systemic oxygen uptake index (V̇O2) and augmented the increase in mixed oxygen saturation (SV̄O2) both of which occurred after CPB. At 0.1 μg · kg-1 · min-1, however, olprinone did not show any significant effect. Conclusion: Our results suggest that olprinone at 0.2 μg · kg-1 · min-1 suppresses gastric intramucosal acidosis and systemic inflammation following CPB..
62. K. Yamaura, M. Higashi, K. Akiyoshi, Y. Itonaga, H. Inoue, S. Takahashi, Pulmonary lipiodol embolism during transcatheter arterial chemoembolization for hepatoblastoma under general anaesthesia, European Journal of Anaesthesiology, 10.1046/j.1365-2346.2000.00759.x, 17, 11, 704-708, 2000.11, We present a case of pulmonary embolism that occurred during the injection of lipiodol during transcatheter arterial chemoembolization under general anaesthesia. A 7-year-old child suffering from a large hepatoblastoma was admitted for arterial chemoembolization and carcinostatic administration. Pulmonary embolism due to lipiodol during arterial chemoembolization was evident by a sudden fall in oxyhaemoglobin saturation from 100 to 90%. This was associated with a spread of lipiodol into both lungs, particularly the middle lung zones and detected by chest fluoroscopy. Arterial blood gases returned to normal values 1 day later but pulmonary infiltration persisted for 7 days before final clearance. Pulmonary embolism caused by lipiodol during arterial chemoembolization is infrequent, but such a complication could prove fatal. Understanding the risk of pulmonary embolism in patients receiving lipiodol, during and after arterial chemoembolization, and late onset pulmonary injury is important and a close follow-up for several days after arterial chemoembolization is advisable..
63. Ken Yamaura, Sumio Hoka, Hirotsugu Okamoto, Tadashi Kandabashi, Kozaburo Akiyoshi, Shosuke Takahashi, Changes in left ventricular end-diastolic area, end-systolic wall stress, and fractional area change during anesthetic induction with propofol or thiamylal, Journal of Anesthesia, 10.1007/s005400070021, 14, 3, 138-142, 2000.01, Purpose. To elucidate the mechanisms of the more profound hypotensive effects of propofol relative to thiamylal, we monitored changes in left ventricular (LV) preload, afterload, and contractility during the course of anesthetic induction with propofol and thiamylal. Methods. Thirty-two patients (ASA I) were randomly assigned into two groups and injected with propofol (2mg·kg-1) or thiamylal (4mg·kg-1) as anesthetic induction agents. Transthoracic echocardiography (TTE) was used to assess LV performance before and during induction by the two anesthetics. The LV end-diastolic area (EDA) and LV end-systolic wall stress (ESWS) were used as indices of LV preload and LV afterload, respectively, while LV contractility was assessed by the fractional area change (FAC). Results. Both propofol and thiamylal significantly reduced EDA and ESWS without significant change in FAC. Propofol-induced reductions in EDA and ESWS were significantly greater than those of thiamylal. Conclusion. The more profound hypotension observed during induction of anesthesia with propofol is due to the greater decrease in preload and afterload than with thiamylal, but not to a decrease in LV contractility..
64. Ken Yamaura, Hirotsugu Okamoto, Toshihiko Maekawa, Tomoo Kanna, Kazuo Irita, Shosuke Takahashi, Detection of retroperitoneal hemorrhage by transesophageal echocardiography during cardiac surgery, Canadian Journal of Anaesthesia, 10.1007/BF03012551, 46, 2, 169-172, 1999.01, Purpose: To present a case of massive retroperitoneal hemorrhage during cardiopulmonary bypass (CPB) which was detected using transesophageal echocardiography (TEE). Clinical feature: A 50-yr-old man suffering from severe mitral regurgitation (MR) was admitted for mitral valvuloplasty. After the beginning of CPB, the volume in the reservoir was noticed to be gradually decreasing. Although venous cannulation had been properly performed, TEE showed an echo free space around the liver, the spleen and in front of the abdominal aorta showed intraabdominal hemorrhage. After cardiac surgery, emergency laparotomy revealed about 5,000 ml of blood in the retroperitoneal space probably as a result of femoral artery cannulation prior to CPB. Hemostasis was achieved, and the patient made complete cardiac and neurological recovery. Retrospective review of the TEE imaging revealed that the kidneys were surrounded by blood bilaterally confirming the diagnosis of retroperitoneal hemorrhage. Conclusion: Retroperitoneal hemorrhage during CPB is rare but may be lethal. Transesophageal echocardiography is a useful monitor not only to evaluate cardiac performance, but also to detect unexpected intraabdominal bleeding during cardiac surgery..
65. Ken Yamaura, Hirotsugu Okamoto, Kozaburo Akiyoshi, Kazuo Irita, Takuro Taniyama, Shosuke Takahashi, Effect of low-dose milrinone on gastric intramucosal pH and systemic inflammation after hypothermic cardiopulmonary bypass, Journal of Cardiothoracic and Vascular Anesthesia, 10.1053/jcan.2001.21954, 15, 2, 197-203, 2001.01, Objective: To investigate the usefulness of low-dose milrinone on gastric intramucosal pH (pHi) and systemic inflammation in patients undergoing hypothermic cardiopulmonary bypass (CPB). Design: Prospective randomized study. Setting: University hospital. Participants: Twenty patients scheduled for cardiac surgery. Interventions: Ten patients were administered a low dose of milrinone, 0.25 μg/kg/min, from the initiation of CPB to 1 hour after admission to the intensive care unit. The other patients were administered saline. Supplemental inotropes and intravenous fluid were given to obtain adequate mean arterial blood pressure and pulmonary artery occlusion pressure. Measurements and Main Results: Gastric phi and carbon dioxide pressure (PCO2) were assessed by capnometric air tonometry. The difference between PCO2 and arterial carbon dioxide pressure (PaCO2), PCO2-gap, was also examined. Systemic inflammatory responses were evaluated by serum interleukin-6 and leukocyte counts. Hemodynamics, oxygen delivery index, and oxygen uptake index were monitored with catheters in the radial and pulmonary arteries (thermodilution). The hepatic venous blood flow and left ventricular flow were measured using transesophageal echocardiography. Milrinone prevented gastric intramucosal acidosis, detected as a decrease in phi or an increase in PCO2-gap, without affecting hepatic venous blood flow. Increases in interleukin-6, leukocyte count, and oxygen uptake index, all of which developed after CPB, were significantly less in the milrinone group than in the control group. Conclusion: These results suggest that in patients undergoing hypothermic CPB, supplemental low-dose milrinone prevents gastric intramucosal acidosis and increases in some markers of systemic inflammation..
66. Sumio Hoka, Ken Yamaura, Tomoaki Takenaka, Shosuke Takahashi, Propofol-induced increase in vascular capacitance is due to inhibition of sympathetic vasoconstrictive activity, Anesthesiology, 10.1097/00000542-199812000-00028, 89, 6, 1495-1500, 1998.12, Background: Venodilation is thought to be one of the mechanisms underlying propofol-induced hypotension. The purpose of this study is to test two hypotheses: (1) propofol increases systemic vascular capacitance, and (2) the capacitance change produced by propofol is a result of an inhibition of sympathetic vasoconstrictor activity. Methods: In 33 Wistar rats previously anesthetized with urethane and ketamine, vascular capacitance was examined before and after propofol infusion by measuring mean circulatory filling pressure (P(mcf)). The P(mcf) was measured during a brief period of circulatory arrest produced by inflating an indwelling balloon in the right atrium. Rats were assigned into four groups: an intact group, a sympathetic nervous system (SNS)-block group produced by hexamethonium infusion, a SNS- block + noradrenaline (NA) group, and a hypovolemic group. The P(mcf) was measured at a control state and 2 min after a bolus administration of 2, 10, and 20 mg/kg of propofol. Results: The mean arterial pressure (MAP) was decreased by propofol dose-dependently in intact, hypovolemic, and SNS-block groups, but the decrease in MAP was less in the SNS-block group (-25%) than in the intact (-50%) and hypovolemic (-61%) groups. In the SNS-block + NA group, MAP decreased only at 20 mg/kg of propofol (-18%). The P(mcf) decreased in intact and hypovolemic groups in a dose-dependent fashion but was unchanged in the SNS-block and SNS-block + NA groups. Conclusions: The results have provided two principal findings: (1) propofol decreases P(mcf) dose-dependently, and (2) the decrease in P(mcf) by propofol is elicited only when the sympathetic nervous system is intact, suggesting that propofol increases systemic vascular capacitance as a result of an inhibition of sympathetic nervous system..
67. Sumio Hoka, Hirotsugu Okamoto, Ken Yamaura, Shosuke Takahashi, Ryuji Tominaga, Hisataka Yasui, Removal of retained air during cardiac surgery with transesophageal echocardiography and capnography, Journal of Clinical Anesthesia, 10.1016/S0952-8180(97)00100-1, 9, 6, 457-461, 1997.09, Study Objective: To evaluate a new method for removal of retained air at the end of cardiopulmonary bypass (CPB) by end-tidal CO2 pressure (P(ET)CO2) and pulmonary arterial pressure (PAP) monitoring, and transesophageal two-dimensional echocardiogra phy (TEE). Design: Prospective study. Setting: Cardiac surgery unit at a university hospital. Patients: 36 ASA physical status I, II, and III patients for open heart surgery. Interventions: The CPB reservoir was gradually raised to decrease venous drainage. Accordingly, the right heart began to receive the venous blood and eject it to the pulmonary artery. The vent existing in the left ventricle or the left atrium then collected any whole blood containing aft bubbles that came from the pulmonary circulation. The air bubbles were confirmed by TEE to be removed and not to eject from the left ventricle to the systemic circulation. Measurements and Main Results: Levels of P(ET)CO2, PaCO2, PAP, and the duration of the removal procedure were measured when a sufficient pulmonary circulation was established and the removal of retained air was considered to be satisfactorily accomplished by the absence of air bubbles, confirmed by TEE for more than 30 seconds. P(ET)CO2 reached 28 ± 4 mmHg during the removal of air, while PaCO2 reached 35 ± 6 mmHg (p < 0.05). Mean PAP during removal of air reached 18 ± 4 mmHg, which was approximately 90% of that before CPB. The duration time of removal of air was 9 ± 2 min. Conclusions: P(ET)CO2 and PAP are useful indicators of pulmonary circulation during this procedure for removal of air, P(ET)CO2 of 25 to 30 mmHg and PAP of 90% of the prebypass level have been found to be necessary for the removal of air. Our technique for removal of air using P(ET)CO2, PAP, and TEE enables us to satisfactorily eliminate residual air..
68. T. Okuyama, S. Hoka, H. Okamoto, T. Kawasaki, K. Yamaura, S. Takahashi, α1-adrenoceptor stimulation is able to reverse halothane-induced cardiac depression in isolated rat hearts, Acta Anaesthesiologica Scandinavica, 10.1111/j.1399-6576.1997.tb04812.x, 41, 7, 939-944, 1997.01, Background. Stimulation of myocardial α1-adrenoceptors has been shown to exert positive inotropic effects through a cyclic AMP-independent mechanism. The purpose of this study was to examine if α1-adrenoceptor stimulation is able to attenuate myocardial depression produced by exposure to halothane, and to test if α1-adrenoceptor stimulation alters myocardial oxygen supply-demand balance in hearts exposed to halothane. Methods. The effects of phenylephrine were examined in 7 isolated perfused rat hearts. Variables measured were: heart rate, isovolumetric peak left ventricular pressure (LVP), LV dP/dt, coronary arterial flow, myocardial O2 delivery (DO2), myocardial O2 consumption (MVO2) and the ratio of DO2/MVO2. Each heart was exposed to phenylephrine cumulatively 0.1 μM, 0.3 μM, 1 μM and 3 μM under the administration of 1% halothane in the presence of propranolol 1 μM. Results. Halothane 1% decreased the heart rate by 9±3%, LVP by 37±3%, and LV dP/dt by 35±2%. Phenylephrine restored these decreases to the baseline levels. Phenylephrine maintained or further enhanced the reductions in coronary flow and DO2 produced by halothane, resulting in a decrease in the DO2/MVO2 ratio. Conclusion. α1-adrenoceptor stimulation is capable of restoring direct cardiac depressant effects of halothane with a possible impairment of the oxygen supply-demand balance..
69. Ju Tae Sohn, Sumio Hoka, Ken Yamaura, Shosuke Takahashi, Effect of nicardipine on vascular capacitance
Comparison with sodium nitroprusside during induced hypotension, Journal of Anesthesia, 10.1007/BF02471391, 10, 3, 199-203, 1996.09, The purpose of this study was to examine the effects of nicardipine and sodium nitroprusside (SNP) on vascular capacitance in the rat. In ten rats anesthetized with pentobarbital, mean arterial pressure was lowered to about 70 mmHg and subsequently 50 mmHg by intravenous infusion of nicardipine or SNP. Vascular capacitance was assessed before and during nicardipine- or SNP-induced hypotension by measuring the mean circulatory filling pressure (MCFP). MCFP was measured during a brief period of circulatory arrest produced by inflating a balloon inserted in the right atrium. MCFP was significantly decreased by SNP from 7.1 ±0.3 mmHg at control to 5.6 ± 0.4 mmHg and 4.4 ± 0.3 mmHg at mean arterial pressures of 70 mmHg and 50 mmHg, respectively. However, MCFP stayed at a similar level to that of the control during nicardipine-induced hypotension. These results suggest that nicardipine has a negligible influence on vascular capacitance during induced hypotension, whereas SNP has a potent vasodilating effect on the venous system as well as the arterial system..
70. Ken Yamaura, Bunsho Kao, Emiko Iimori, Hidekazu Urakami, Shosuke Takahashi, Recurrent ventricular tachyarrhythmias associated with QT prolongation following hydrofluoric acid burns, Journal of Toxicology - Clinical Toxicology, 35, 3, 311-313, Background: Some hydrofluoric acid burns appear initially as only a slight wound, but patients may show dramatic changes within several hours. The extent of such burns are directly related to the concentration, amount, and duration of exposure. Case Report: A 64-year-old man sustained 44% total body surface burns after exposure to 30% hydrofluoric acid. Approximately 5 h after injury, he developed recurrent ventricular tachycardia and ventricular fibrillation which occurred in conjunction with long QT syndrome. In this case, the occurrence of hypocalcemia and especially hypomagnesemia played an important role in the development of long QT syndrome..