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Microwave applications, such as microwave ovens and mobile phones, are ubiquitous and indispensable in modern society. As the utilization of microwave technology is becoming more widespread, the effects of microwaves on living organisms and physiological processes have received increased attention. This study aimed to investigate the effects of microwaves on calcium carbonate biomineralization as a model biochemical process. A magnetron oscillator was used to generate 2450 MHz microwaves because magnetrons are relatively inexpensive and widespread. We conducted transmission electron microscopy (TEM), atomic force microscopy (AFM), TEM-electron energy-loss spectroscopy (EELS), dynamic light scattering (DLS), and high-performance liquid chromatography (HPLC) measurements to analyze the calcium carbonate precipitates. Our findings showed the formation of string-like precipitates of calcium carbonate upon microwave irradiation from one direction, similar to those obtained using a semiconductor oscillator, as reported previously. This implied that the distribution of the frequency had little effect on the morphology. Furthermore, spherical precipitates were obtained upon microwave irradiation from two directions, indicating that the morphology could be controlled by varying the direction of microwave irradiation. Magnetrons are versatile and also used in large-scale production; thus, this method has potential in medical and industrial applications. [ABSTRACT FROM AUTHOR]

Purpose Intraoperative anxiety is the most common psychological response of the patient during awake craniotomy. Psychological stress can trigger patient decline, resulting in failed awake craniotomy and significantly poor outcomes. This study aimed to identify the risk factors for panic attack (PA) during awake craniotomies. Methods With the local ethics committee approval, we conducted a manual chart review of the medical record of patients who underwent consecutive awake craniotomies between November 1999 and October 2016 at Tokyo Women's Medical University. A total of 405 patients were identified and assigned to 2 groups based on the Diagnostic and Statistical Manual of Mental Disorders-V criteria: those that met the PA criteria (Group PA) and those that did not (Group non-PA). Patient characteristics and the incidence of the PA specifier were collected. The features of the two groups were statistically compared, and risk factors for PA occurrence were determined by regression analysis. Results Sixteen of 405 patients met the diagnostic criteria of PA. Patients' characteristics were not statistically different between the groups. Multivariate logistic regression showed that intraoperative anxiety (p = 0.0002) and age younger than 39 years (as opposed to age > = 39 years; p = 0.0328) were significantly associated with the occurrence of PA during awake craniotomy. Conclusions For patients undergoing awake craniotomy, intraoperative anxiety and age younger than 39 years were considered risk factors of PA. As PA often necessitates conversion to general anesthesia, intensive perioperative psychological support and pain management are required to achieve patient satisfaction and the surgical goal of awake craniotomy., Author(s): Kotoe Kamata [sup.1] [sup.2], Takashi Maruyama [sup.3], Ryu Komatsu [sup.4], Makoto Ozaki [sup.2] [sup.5] Author Affiliations: (1) grid.69566.3a, 0000 0001 2248 6943, Department of Anesthesiology and Perioperative Medicine, Tohoku [...]

To this day, the pathophysiology and risk factors of propofol infusion syndrome (PRIS) remain unknown. Moreover, there is no widely accepted definition of PRIS, even though it is a potentially fatal condition. While many suspected cases of PRIS have been reported in both pediatric and adult populations, the actual propofol plasma concentration (Cp) has never been clarified. In this clinical report, we described the first suspected PRIS case in which the propofol Cp was measured 25 min after 226 min of propofol infusion (7.2 [micro]g/mL), which was 12 times higher than the predicted value (0.6 [micro]g/mL). In the presented case, we observed gradually progressive uncontrollable hypercapnia and tachycardia, followed by severe lactic acidosis during surgical anesthesia based on the target-controlled infusion of propofol. Levels of liver enzymes were slightly elevated which suggests little or no liver damage though propofol is mainly metabolized by the liver. Meanwhile, renal impairment, a common secondary feature of PRIS, occurred concomitantly when hypercapnia and metabolic acidosis were manifested. In this case, low or delayed propofol clearance might have been a triggering factor causing severe lactic acidosis., Author(s): Taku Ichikawa [sup.1], Keiko Okuyama [sup.1], Kotoe Kamata [sup.1] [sup.2], Kenichi Masui [sup.3], Makoto Ozaki [sup.1] Author Affiliations: (1) grid.410818.4, 0000 0001 0720 6587, Department of Anesthesiology, Tokyo Women's [...]

Purpose We retrospectively studied perioperative management of patients receiving opioid treatment for cancer pain to facilitate establishing a standard policy for our institute. Methods Subjects were patients who had been administered strong opioids for cancer pain and had undergone surgery with general anesthesia. We divided the patients into groups C and D. Group C was comprised of patients who had been administered their baseline opioids continuously during the perioperative period, and group D of those who had discontinued baseline opioid use during this period. Results We identified 70 evaluable patients, 36 in group C and 34 in group D. The intraoperative anesthesia courses were similar, being uneventful, in all cases. With respect to postoperative adverse effects within 24 h after awakening from anesthesia, severe adverse effects (additional administration of more than four analgesics and intense agitation) were significantly more frequent in group D than in group C (12 vs 1, respectively. p = 0.004). Univariate analysis revealed that baseline opioid discontinuation was the only factor associated with severe adverse effects [odds ratio 12.6, 95% confidence interval (1.49-105.8), p = 0.01]. Conclusion Discontinuation of baseline opioid increased adverse effects in the early postoperative period, which were attributed to exacerbation of early postoperative pain., Author(s): Takako Fujita [sup.1] , Motoyo Iwade [sup.1] , Keiko Hamada [sup.1] , Makoto Ozaki [sup.1] Author Affiliations: (Aff1) 0000 0001 0720 6587, grid.410818.4, Department of Anesthesiology, Tokyo Women's Medical [...]

Purpose Although capnography is considered the gold standard for monitoring of ventilation, it may not work accurately in some situations. We compared the performance of two non-invasive continuous respiratory rate (RR) monitors that are alternatives for the detection of respiratory depression. Methods Fifty healthy volunteers [greater than or equal to]20 years old were enrolled in this study. After monitoring of the volunteers was started by the Masimo Radical-7.sup.® and Nellcor[TM] PM1000N, they breathed at the rate of 12 breaths/min for 3 min and then stopped breathing. As soon as the apnea alarm of either monitor went off, breathing was resumed at the same rate. This entire procedure was repeated three times. The data collected every 30 s included the RR, pulse rate (PR) and oxygen saturation (SpO.sub.2). The times of alarm on, alarm off and reappearance of RR on the monitor screens were also recorded. Results The biases of the RR, PR and SpO.sub.2 measurements from the two monitors were 0.5, 0.2 and -0.4, respectively. Of 143 procedures that stopped breathing for more than 30 s, 114 and 15 alarms were shown by the Masimo Radical-7.sup.® and Nellcor[TM] PM-1000N monitors, respectively. Most alarms of the Nellcor[TM] PM1000N followed from SpO.sub.2 Conclusions The Masimo Radical-7.sup.® monitor provides better detection of apnea in volunteers than the Nellcor[TM] PM-1000N., Author(s): Chanatthee Kitsiripant [sup.1] [sup.2] , Tomoko Fukada [sup.1] , Hiroko Iwakiri [sup.1] , Yuri Tsuchiya [sup.1] , Makoto Ozaki [sup.1] , Minoru Nomura [sup.1] Author Affiliations: (1) Department of [...]

Purpose There is still no easy and highly useful method to comprehensively assess both preoperative and intraoperative patient statuses to predict postoperative outcomes. We attempted to develop a new scoring system that would enable a comprehensive assessment of preoperative and intraoperative patient statuses instantly at the end of anesthesia, predicting postoperative mortality. Methods The study included 32,555 patients who underwent surgery under general or regional anesthesia from 2008 to 2012. From the anesthesia records, extracted factors, including patient characteristics and American Society of Anesthesiologists physical status classification (ASA-PS), and three intraoperative indexes (the lowest heart rate, lowest mean arterial pressure, and estimated volume of blood loss) are used to calculate the surgical Apgar score (sAs). The sAs and ASA-PS, and surgical Apgar score combined with American Society of Anesthesiologists physical status classification (SASA), which combines the sAs and ASA-PS into a single adjusted scale, were compared and analyzed with postoperative 30-day mortality. Results Increased severity of the sAs, ASA-PS and SASA was correlated with significantly higher mortality. The risk of death was elevated by 3.65 for every 2-point decrease in the sAs, by 6.4 for every 1-point increase in the ASA-PS, and by 9.56 for every 4-point decrease in the SASA. The ROC curves of the sAs and ASA-PS alone also individually demonstrated high validity (AUC = 0.81 for sAs and 0.79 for ASA-PS, P < 0.001). The SASA was even more valid (AUC = 0.87, P < 0.001). Conclusions The sAs and ASA-PS were shown to be extremely useful for predicting 30-day mortality after surgery. An even higher predictive ability was demonstrated by the SASA, which combines these simple and effective scoring systems., Author(s): Maho Kinoshita [sup.1] , Nobutada Morioka [sup.1] , Mariko Yabuuchi [sup.1] , Makoto Ozaki [sup.1] Author Affiliations: (1) grid.410818.4Department of Anesthesiology, Tokyo Women's Medical University, Shinjuku, 1628666, Tokyo, Japan [...]

Purpose Intraoperative vomiting leads to serious respiratory complications that could influence the surgical decision-making process for awake craniotomy. However, the use of antiemetics is still limited in Japan. The aim of this study was to investigate the effect of prophylactically administered single low-dose dexamethasone on the incidence of vomiting during awake craniotomy. The frequency of hyperglycemia was also examined. Methods We conducted a retrospective case review of awake craniotomy for glioma resection between 2012 and 2015. Results Of the 124 patients, 91 were included in the analysis. Dexamethasone was not used in 43 patients and the 48 remaining patients received an intravenous bolus of 4.95 mg dexamethasone at anesthetic induction. Because of stable operating conditions, no one required conscious sedation throughout functional mapping and tumor resection. Although dexamethasone pretreatment reduced the incidence of intraoperative vomiting (P = 0.027), the number of patients who complained of nausea was comparable (P = 0.969). No adverse events related to vomiting occurred intraoperatively. Baseline blood glucose concentration did not differ between each group (P = 0.143), but the samples withdrawn before emergence (P = 0.018), during the awake period (P < 0.0001) and at the end of surgery (P < 0.0001) showed significantly higher glucose levels in the dexamethasone group. Impaired wound healing was not observed in either group. Conclusion A single low-dose of dexamethasone prevents intraoperative vomiting for awake craniotomy cases. However, as even a small dose of dexamethasone increases the risk for hyperglycemia, antiemetic prophylaxis with dexamethasone should be administered after careful consideration. Monitoring of perioperative blood glucose concentration is also necessary., Author(s): Kotoe Kamata[sup.1] , Nobutada Morioka[sup.1] , Takashi Maruyama[sup.2] [sup.3] , Noriaki Komayama[sup.1] , Masayuki Nitta[sup.2] [sup.3] , Yoshihiro Muragaki[sup.2] [sup.3] , Takakazu Kawamata[sup.2] , Makoto Ozaki[sup.1] Author Affiliations: (1) [...]

Purpose The heparin dose-response (HDR) technique is based on activated clotting time (ACT) response to a fixed-dose heparin bolus, which varies substantially among patients. It is unclear, however, whether hemodilution-associated reductions in coagulation and anticoagulation factors affect the HDR slope. Methods For in vitro hemodilution, aliquots of whole blood from healthy volunteers were diluted 9:1 and 8:2 v/v with normal saline. For in vivo hemodilution, a prospective observational study was performed on 46 patients who underwent elective cardiovascular surgery with or without cardiopulmonary bypass. HDR slope, antithrombin (AT) activity, complete blood count, and other coagulation parameters were compared after induction of anesthesia and after hemodilution with 500 ml of intravenous fluid. Results In vitro 10 and 20 % hemodilution significantly increased the HDR slope relative to baseline, reducing the heparin requirement. Hemodilution of heparinized samples significantly prolonged ACT, whereas there was no significant change in non-heparinized blood. The percent changes in fibrinogen and AT activity were significantly greater at 20 % than those of the other coagulation variables. In vivo, hemodilution significantly increased the HDR slope and reduced heparin requirement. The percent change in fibrinogen due to hemodilution was significantly greater than the change in AT activity. Target ACTs of 300 and 450 s were not achieved in 83.3 and 53.8 % of patients, respectively. Conclusion In vitro and in vivo hemodilution significantly increased the HDR slope and reduced the requirement for heparin. In vitro, the HDR slope did not change in parallel but became steeper, depending on the degree of hemodilution., Author(s): Junko Ichikawa[sup.1] , Satoshi Hagihira[sup.2] , Testu Mori[sup.1] , Mitsuharu Kodaka[sup.1] , Keiko Nishiyama[sup.1] , Makoto Ozaki[sup.3] , Makiko Komori[sup.1] Author Affiliations: (1) Department of Anesthesiology, Tokyo Women's Medical [...]