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Dive into the research topics where Masayuki Suzukawa is active.

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Featured researches published by Masayuki Suzukawa.


Journal of Trauma-injury Infection and Critical Care | 2014

Predicting the need for massive transfusion in trauma patients: the Traumatic Bleeding Severity Score.

Takayuki Ogura; Yoshihiko Nakamura; Minoru Nakano; Yoshimitsu Izawa; Mitsunobu Nakamura; Kenji Fujizuka; Masayuki Suzukawa; Alan T. Lefor

BACKGROUND The ability to easily predict the need for massive transfusion may improve the process of care, allowing early mobilization of resources. There are currently no clear criteria to activate massive transfusion in severely injured trauma patients. The aims of this study were to create a scoring system to predict the need for massive transfusion and then to validate this scoring system. METHODS We reviewed the records of 119 severely injured trauma patients and identified massive transfusion predictors using statistical methods. Each predictor was converted into a simple score based on the odds ratio in a multivariate logistic regression analysis. The Traumatic Bleeding Severity Score (TBSS) was defined as the sum of the component scores. The predictive value of the TBSS for massive transfusion was then validated, using data from 113 severely injured trauma patients. Receiver operating characteristic curve analysis was performed to compare the results of TBSS with the Trauma-Associated Severe Hemorrhage score and the Assessment of Blood Consumption score. RESULTS In the development phase, five predictors of massive transfusion were identified, including age, systolic blood pressure, the Focused Assessment with Sonography for Trauma scan, severity of pelvic fracture, and lactate level. The maximum TBSS is 57 points. In the validation study, the average TBSS in patients who received massive transfusion was significantly greater (24.2 [6.7]) than the score of patients who did not (6.2 [4.7]) (p < 0.01). The area under the receiver operating characteristic curve, sensitivity, and specificity for a TBSS greater than 15 points was 0.985 (significantly higher than the other scoring systems evaluated at 0.892 and 0.813, respectively), 97.4%, and 96.2%, respectively. CONCLUSION The TBSS is simple to calculate using an available iOS application and is accurate in predicting the need for massive transfusion. Additional multicenter studies are needed to further validate this scoring system and further assess its utility. LEVEL OF EVIDENCE Prognostic study, level III.


Anesthesia & Analgesia | 1983

Use of Isoflurane during Resection of Pheochromocytoma

Masayuki Suzukawa; Ira Michaels; Joseph Ruzbarsky; Charles J. Kopriva; Luke M. Kitahata

Patients with pheochromocytomas have been successfully anesthetized with a variety of anesthetic agents including diethyl ether (l), methoxyflurane (2), halothane (3), enflurane (4), and nitrous oxide narcotic technique (5). Of these agents currently in use, halothane is undesirable because it is associated with a high incidence of serious ventricular arrhythmias during resection of a pheochromocytoma (3). Nitrous oxide narcotic technique may be associated with both hypotension and hypertension. Recently, enflurane has been used with good results (4): it depresses myocardial irritability (6), but causes convulsive EEG changes (7), is metabolized to inorganic fluoride (8), and has potential toxicity in patients with pre-existing kidney disease or seizure disorders. Small amounts of free fluoride ion accumulate during the metabolism of enflurane. The resultant fluoride levels do not damage normal kidneys, but Mazze et al. (9) have suggested that these low levels could cause deterioration of renal function in a patient with pre-existing kidney disease. Isoflurane, an isomer of enflurane, also decreases myocardial irritability (6), but does not produce convulsive EEG changes (10) and is more resistant to biodegradation (11). We have used isoflurane to anesthetize two patients with pheochromocytomas; one of them had an elevated blood urea nitrogen (BUN) and the other had a history of seizures.


Anesthesia & Analgesia | 1985

Fentanyl and alfentanil suppress brainstem pain transmission.

Osafumi Yuge; Luke M. Kitahata; J. G. Collins; Maki Matsumoto; Mahmood Tabatabai; Masayuki Suzukawa; Akio Tanaka

The effects of intravenously administered fentanyl (25 μg/kg, n = 9; 50 μg/kg, n = 5) and alfentanil (12.5 μg/kg, n = 5; 25 μg/kg, n = 7) on the noxiously evoked, single-unit activity of cells in the nucleus reticularis gigantocellularis (NRGC) were studied in decerebrate cats. Only cells of the NRGC excited exclusively by supramaximal electrical stimulation of A delta fibers (noxious stimulation) of the superficial radial nerve were studied. The noxiously evoked activity of all cells in the NRGC was suppressed by the administration of opioids (by 58 and 88% for fentanyl, 25 μg/kg and 50 μg/kg, respectively; by 35 and 78% for alfentanil 12.5 μg/kg and 25 μg/kg, respectively). Fentanyl and alfentanil effects were antagonized by the intravenous administration of naloxone. These results indicate that opioid suppression of noxiously evoked activity is seen in neurons located in the brainstem, and thus suppression of brainstem neurons may be important in the production of fentanyl and alfentanil analgesia.


Case Reports in Medicine | 2012

Takotsubo Cardiomyopathy as a Delayed Complication with a Herbicide Containing Glufosinate Ammonium in a Suicide Attempt: A Case Report

Keiichiro Tominaga; Manabu Izumi; Masayuki Suzukawa; Takafumi Shinjo; Yoshimitsu Izawa; Chikara Yonekawa; Masaki Ano; Keisuke Yamashita; Tomohiro Muronoi; Reiko Mochiduki

Background. Glufosinate ammonium has a famous delayed complication as respiratory failure, however, delayed cardiogenic complication is not well known. Objectives. The aim of this study is to report a takotsubo cardiomyopathy as a delayed complication of glufosinate ammonium for suicide attempt. Case Report. A 75-year-old woman ingested about 90 mL of Basta, herbicide for suicide attempt at arousal during sleep. She came to our hospital at twelve hours after ingesting. She was admitted to our hospital for fear of delayed respiratory failure. Actually, she felt down to respiratory failure, needing a ventilator with intubation at 20 hours after ingesting. Procedure around respiratory management had smoothly done with no delay. Her vital status had been stable, however, she felt down to circulatory failure and diagnosed as Takotsubo cardiomyopathy at about 41 hours after ingestion. There was no trigger activities or events to evoke mental and physical stresses. Conclusion. We could successfully manage takotsubo cardiomyopathy resulted in circulatory failure in a patient with glufosinate poisoning for suicide attempt. Takotsubo cardiomyopathy should be taken into consideration if circulatory failure is observed for unexplained reasons.


Thrombosis Research | 2016

Immature platelet fraction predicts coagulopathy-related platelet consumption and mortality in patients with sepsis

Tomohiro Muronoi; Kansuke Koyama; Shin Nunomiya; Alan Kawarai Lefor; Masahiko Wada; Toshitaka Koinuma; Jun Shima; Masayuki Suzukawa

INTRODUCTION The diagnostic and prognostic value of immature platelet fraction (IPF) in sepsis has not been determined. This study aimed to assess whether IPF is an early predictor of platelet decline due to coagulopathy and is associated with mortality in patients with sepsis. MATERIALS AND METHODS In total, 149 patients with a platelet count of ≥80×10(3)/μL on intensive care unit admission (101 with sepsis, 48 controls without sepsis) were prospectively evaluated. We measured IPF on admission and observed for development of subsequent platelet count decline (defined as a >30% decrease or <80×10(3)/μL) in 5days, and mortality at 28days. The absolute immature platelet count (AIPC) was calculated to evaluate thrombopoiesis. RESULTS Forty-seven patients with sepsis subsequently developed a decrease in platelet count. The IPF was highest in patients whose platelet count decreased, followed by patients without a decrease in platelet count and controls (median, 4.3% [3.1%-8.1%] vs. 3.7% [2.6%-4.6%] vs. 2.1% [1.6%-3.5%], respectively; P<0.0001). The AIPC was similar in patients with and without a decrease in platelet count (7.6 [4.2-10.0] vs. 5.9 [4.2-8.7]×10(3)/μL, respectively; P=0.32). Coagulation derangement was more severe in patients who did than did not subsequently develop a decreased platelet count. Cox regression and receiver operator characteristic curve analysis revealed that IPF was a strong independent predictor of mortality, with accuracy similar to a standard prognostic scoring system. CONCLUSIONS The admission IPF in septic patients predicts a subsequent decrease in platelet count, indicating platelet consumption with ongoing coagulopathy and risk of poor prognosis.


Journal of Telemedicine and Telecare | 2014

Development of a first-responder dispatch system using a smartphone:

Chikara Yonekawa; Masayuki Suzukawa; Keisuke Yamashita; Katsuaki Kubota; Yasuharu Yasuda; Akihiro Kobayashi; Hiroki Matsubara; Yoshiki Toyokuni

We constructed a prototype community first responder (CFR) dispatch system. The system sends incident information, including a map, to the chosen CFRs mobile phone. We tested it in a simulation of 30 out-of-hospital cardiac arrest incidents which had occurred in the town of Motegi during the previous year. Thirty off-duty firefighters acted as CFRs and were sent to the same locations. The mean response time (from the CFR receiving dispatch information to arrival at the scene) was 3 min 37s faster than the actual response time in the corresponding historical control, i.e. the response time was reduced by 36% (P < 0.01). The median travel distance of the CFRs was 3.4 km and there was a positive correlation between response time and travel distance. The study showed that interactive communication between dispatcher and CFR was important for effective operation and that CFRs could reach an OHCA patient before the Emergency Medical Service arrives.


Anesthesia & Analgesia | 1993

Pulmonary capillary pressure measured with a pulmonary arterial double port catheter in surgical patients.

Yoshitsugu Yamada; Kyoko Komatsu; Masayuki Suzukawa; Chinzei M; Tsuneo Chinzei; Kunio Suwa; Katsuo Numata; Kazuo Hanaoka

We developed a pulmonary artery (PA) double port catheter technique for reliable clinical measurements of pulmonary capillary pressure (Ppc). In seven elective surgical patients, the PA double port catheter with the second PA port 1 cm proximal to the balloon was inserted. The two PA ports, connected to identical pressure measuring systems, provided the pulmonary arterial pressures (Ppa) distal and proximal to the balloon. After general anesthesia was stabilized, the two Ppas were measured simultaneously during a PA occlusion maneuver during 10 s of apnea. The instant of occlusion was determined precisely as the time when the two Ppa traces sharply diverged. A single exponential equation was fitted to the segment of distal Ppa tracing starting 0.3 s after the instant of occlusion. Ppc was determined as the value of the exponential fit extrapolated to time 0. In six of seven patients, PA occlusion occurred consistently in the early systolic phase regardless of the timing of balloon inflation. Mean Ppa, Ppc, and pulmonary arterial wedge pressure were 16.6, 11.8, and 7.6 torr. The ratio of venous to total resistance ranged from 0.37 to 0.54 (mean:0.46). We conclude that this technique is clinically feasible and valuable in precise definition of the instant of PA occlusion. By defining PA occlusion consistently, this technique can provide reliable Ppc estimation in the clinical settings.


Respiratory investigation | 2017

The Japanese Respiratory Society Noninvasive Positive Pressure Ventilation (NPPV) Guidelines (second revised edition)

Tsuneto Akashiba; Yuka Ishikawa; Hideki Ishihara; Hideaki Imanaka; Motoharu Ohi; Ryoichi Ochiai; Takatoshi Kasai; Kentaro Kimura; Yasuhiro Kondoh; Shigeru Sakurai; Nobuaki Shime; Masayuki Suzukawa; Misa Takegami; Shinhiro Takeda; Sadatomo Tasaka; Hiroyuki Taniguchi; Naohiko Chohnabayashi; Kazuo Chin; Tomomasa Tsuboi; Keisuke Tomii; Koji Narui; Ryuichi Hasegawa; Yoshihito Ujike; Keishi Kubo; Yoshinori Hasegawa; Shin-ichi Momomura; Yoshitsugu Yamada; Masahiro Yoshida; Yukie Takekawa; Ryo Tachikawa

Division of Sleep and Respiratory Medicine, Nihon University School of Medicine Department of Pediatrics, National Hospital Organization Yakumo National Hospital Department of Respiratory Medicine, Osaka Prefectural Medical Center for Respiratory and Allergic Diseases Department of ER/Disaster Medical Care, Tokushima University Hospital Respiratory and Sleep Medicine Center, Osaka Kaisei Hospital Anesthesiology and Intensive Care Medicine of Toho University Omori Medical Center Cardio-Respiratory Sleep Medicine, Department of Cardiovascular Medicine, Juntendo University, Graduate School of


Prehospital and Disaster Medicine | 2014

Predictability of the Call Triage Protocol to Detect if Dispatchers Should Activate Community First Responders.

Kenji Narikawa; Tetsuya Sakamoto; Katsuaki Kubota; Masayuki Suzukawa; Chikara Yonekawa; Keisuke Yamashita; Yoshiki Toyokuni; Yasuharu Yasuda; Akihiro Kobayashi; Kazunori Iijima

INTRODUCTION Shortening response time to an emergency call leads to the success of resuscitation by chest compression and defibrillation. However, response by ambulance or fire truck is not fast enough for resuscitation in Japan. In rural areas, response times can be more than 10 minutes. One possible way to shorten the response time is to establish a system of first responders (eg, police officers or firefighters) who are trained appropriately to perform resuscitation. Another possible way is to use a system of Community First Responders (CFRs) who are trained neighbors. At present, there are no call triage protocols to decide if dispatchers should activate CFRs. OBJECTIVE The aim of this study was to determine the predictability to detect if dispatchers should activate CFRs. METHODS Two CFR call triage protocols (CFR protocol Ver.0 and Ver.1) were established. The predictability of CFR protocols was examined by comparing the paramedic field reports. From the results of sensitivity of CFR protocol, the numbers of annual CFR activations were calculated. All data were collected, prospectively, for four months from October 1, 2012 through January 31, 2013. RESULTS The ROC-AUC values appear slightly higher in CFR protocol Ver.1 (0.857; 95% CI, 79.8-91.7) than in CFR protocol Ver.0 (0.847; 95% CI, 79.0-90.3). The number of annual CFR activations is higher in CFR protocol Ver.0 (7.47) than in CFR protocol Ver.1 (5.45). CONCLUSION Two call triage protocols have almost the same predictability as the Medical Priority Dispatch System (MPDS). The study indicates that CFR protocol Ver.1 is better than CFR protocol Ver.0 because of the higher predictability and low number of activations. Also, it indicates that CFRs who are not medical professionals can respond to a patient with cardiac arrest.


World Journal of Emergency Surgery | 2012

Ex-vivo porcine organs with a circulation pump are effective for teaching hemostatic skills.

Yoshimitsu Izawa; Shuji Hishikawa; Tomohiro Muronoi; Keisuke Yamashita; Masayuki Suzukawa; Alan T. Lefor

Surgical residents have insufficient opportunites to learn basic hemostatic skills from clinical experience alone. We designed an ex-vivo training system using porcine organs and a circulation pump to teach hemostatic skills. Residents were surveyed before and after the training and showed significant improvement in their self-confidence (1.83 ± 1.05 vs 3.33 ± 0.87, P < 0.01) on a 5 point Likert scale. This training may be effective to educate residents in basic hemostatic skills.

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Y. Abe

University of Tokyo

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