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Dive into the research topics where Tomoya Okazaki is active.

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Featured researches published by Tomoya Okazaki.


Journal of intensive care | 2014

Clinical experience with an active intravascular rewarming technique for near-severe hypothermia associated with traumatic injury

Kazutaka Kiridume; Toru Hifumi; Kenya Kawakita; Tomoya Okazaki; Hideyuki Hamaya; Natsuyo Shinohara; Yuko Abe; Koshiro Takano; Masanobu Hagiike; Yasuhiro Kuroda

Hypothermia and acidosis are secondary causes of trauma-related coagulopathy. Here we report the case of a 72-year-old patient with severe trauma who suffered near-severe hypothermia despite the initiation of standard warming measures and was successfully managed with active intravascular rewarming. The patient was involved in a road traffic accident and was transported to a hospital. He was diagnosed with massive right-sided hemothorax, blunt aortic injury, burst fractures of the eighth and ninth thoracic vertebrae, and open fracture of the right tibia. He was referred to our hospital, where emergency surgery was performed to control bleeding from the right hemothorax. During surgery, the patient demonstrated progressive heat loss despite standard rewarming measures, and his temperature decreased to 32.4°C. Severe acidosis was also observed. A Cool Line® catheter was inserted into the right femoral vein and lodged in the inferior vena cava, and an intravascular balloon catheter system was utilized for aggressive rewarming. The automated target core temperature was set at 37°C, and the maximum flow rate was used. His core temperature reached 36.0°C after 125 min of intravascular rewarming. The severe acidosis was also resolved. The main active bleeding site was not identified, and coagulation hemostasis as well as rewarming enabled us to control bleeding from the vertebral bodies, lung parenchyma, and pleura. The total volume of intraoperative bleeding was 5,150 mL, and 20 units of red cell concentrate and 16 units of fresh frozen plasma were transfused. After surgery, he was transferred to the intensive care unit under endotracheal intubation and mechanical ventilation. His hemodynamic condition stabilized after surgery. The rewarming catheter was removed on day 2 of admission, and no bleeding, infection, or thrombosis associated with catheter placement was observed. Extubation was performed on day 40, and his subsequent clinical course was uneventful. He recovered well following rehabilitation and was discharged on day 46. These findings suggest that active intravascular rewarming should be considered as an aggressive, additional rewarming technique in patients with near-severe hypothermia associated with traumatic injury.


Resuscitation | 2017

Association of brain metabolites with blood lactate and glucose levels with respect to neurological outcomes after out-of-hospital cardiac arrest: A preliminary microdialysis study

Toru Hifumi; Kenya Kawakita; Takeshi Yoda; Tomoya Okazaki; Yasuhiro Kuroda

AIM Out-of-hospital cardiac arrest (OHCA) is associated with poor prognosis. Cerebral microdialysis (CMD) is an efficient sampling technique to detect neurochemical changes in brain interstitial tissue. In this retrospective study, we hypothesised that there are different CMD levels between patients with favourable and unfavourable neurological outcomes. METHODS Data of patients with OHCA admitted to Kagawa University Hospital and administered therapeutic hypothermia (TH) were collected. Using a CMD probe, extracellular glucose, lactate and pyruvate levels were measured hourly along with intracranial perfusion pressure (ICP) and cerebral perfusion pressure (CPP) for the initial 72h during TH. The lactate/pyruvate (LP) ratio was calculated. Patients were divided into favourable [Glasgow-Pittsburgh cerebral performance category 1-2 at 30days after cardiac arrest] or unfavourable neurological outcome groups. CMD biochemical markers and blood lactate and glucose levels were compared between two groups. RESULTS Ten patients were included. ICP was significantly higher in the unfavourable than in the favourable neurological outcome group; there were no significant differences with respect to CPP. The CMD LP ratio in the unfavourable outcome group progressively increased; significant differences were observed on days 2, 3 and 4 (p<0.01). Significant differences in blood lactate levels were observed between the groups only on day 3.5. CMD and blood glucose levels were higher in the unfavourable than in the favourable outcome group during TH. CONCLUSION The association of CMD levels with long-term outcomes would be better defined in a large randomised prospective study.AIM Out-of-hospital cardiac arrest (OHCA) is associated with poor prognosis. Cerebral microdialysis (CMD) is an efficient sampling technique to detect neurochemical changes in brain interstitial tissue. In this retrospective study, we hypothesised that there are different CMD levels between patients with favourable and unfavourable neurological outcomes. METHODS Data of patients with OHCA admitted to Kagawa University Hospital and administered therapeutic hypothermia (TH) were collected. Using a CMD probe, extracellular glucose, lactate and pyruvate levels were measured hourly along with intracranial perfusion pressure (ICP) and cerebral perfusion pressure (CPP) for the initial 72h during TH. The lactate/pyruvate (LP) ratio was calculated. Patients were divided into favourable [Glasgow-Pittsburgh cerebral performance category 1-2 at 30days after cardiac arrest] or unfavourable neurological outcome groups. CMD biochemical markers and blood lactate and glucose levels were compared between two groups. RESULTS Ten patients were included. ICP was significantly higher in the unfavourable than in the favourable neurological outcome group; there were no significant differences with respect to CPP. The CMD LP ratio in the unfavourable outcome group progressively increased; significant differences were observed on days 2, 3 and 4 (p<0.01). Significant differences in blood lactate levels were observed between the groups only on day 3.5. CMD and blood glucose levels were higher in the unfavourable than in the favourable outcome group during TH. CONCLUSION The association of CMD levels with long-term outcomes would be better defined in a large randomised prospective study.


Journal of Intensive Care Medicine | 2018

Blood Glucose Variability A Strong Independent Predictor of Neurological Outcomes in Aneurysmal Subarachnoid Hemorrhage

Tomoya Okazaki; Toru Hifumi; Kenya Kawakita; Hajime Shishido; Daisuke Ogawa; Masanobu Okauchi; Atsushi Shindo; Masahiko Kawanishi; Takashi Tamiya; Yasuhiro Kuroda

Purpose: In patients with aneurysmal subarachnoid hemorrhage (SAH), increased glucose variability (GV) is associated with increased mortality and cerebral infarction; however, there are no reports demonstrating an association between GV and neurological outcome. This study investigated whether GV had an independent effect on neurological outcomes in patients with SAH in the intensive care unit. Materials and Methods: Consecutive adult patients hospitalized with SAH between January 1, 2009, and May 31, 2015 (N = 122) were retrospectively reviewed. Univariate/multivariate analyses were performed to identify independent predictors of poor neurological outcome. Patients were divided according to the mean glucose level (80-139 vs 140-200 mg/dL) and further subdivided using quartiles (Q) of the standard deviation (SD, representing variability) of the glucose level (Q1, Q2 + 3, and Q4). Results: Unfavorable neurological outcomes occurred in 44.2% of the patients. On multiple regression analysis, age, Hunt and Kosnik grade, SD of glucose (odds ratio [OR], 1.09; 95% confidence interval [CI], 1.02-1.17; P < .01), and minimum blood glucose level (OR, 0.95; 95% CI, 0.91-0.99; P < .01) were significantly associated with unfavorable neurological outcomes. Both groups (mean glucose levels: 80-139 and 140-200 mg/dL groups) had increasing unfavorable neurological outcomes with increasing SD of glucose (Q1, 15.0%; Q2 + 3, 40.0%; Q4, 52.4% and Q1, 44.4%; Q2 + 3, 50%; Q4, 88.9% in the 80-139 and 140-200 mg/dL groups, respectively). Patients with minimum glucose of <90 mg/dL comprised >50% of unfavorable neurological outcome. Conclusion: Increased GV was an independent predictor of unfavorable neurological outcomes in patients with SAH.


Journal of Critical Care | 2017

Serial blood lactate measurements and its prognostic significance in intensive care unit management of aneurysmal subarachnoid hemorrhage patients

Tomoya Okazaki; Toru Hifumi; Kenya Kawakita; Hajime Shishido; Daisuke Ogawa; Masanobu Okauchi; Atsushi Shindo; Masahiko Kawanishi; Shigeaki Inoue; Takashi Tamiya; Yasuhiro Kuroda

Purpose: This study assesses the behavior of serial blood lactate measurements during intensive care unit (ICU) stay to identify prognostic factors of unfavorable neurological outcomes (UO) in patients with aneurysmal subarachnoid hemorrhage (SAH). Methods: We retrospectively reviewed all patients who were consecutively hospitalized with SAH between 2009 and 2016. Arterial blood lactate levels were routinely obtained on admission and every 6 h in the ICU. Univariate/multivariate analyses were performed to identify independent predictors of UO (modified Rankin scale of 3–6 upon hospital discharge). Results: There were 145 patients with 46% of UO. Initially, increased lactate levels reached maximum levels during the first 24 h and then decreased to within the normal range. Then, the levels slightly increased again to within the normal range for the next 24 h, especially in UO. On multiple regression analysis, lactate levels measured at 24 h, and 48 h after admission were strong predictors of UO. Lactate level measured at 48 h after admission demonstrated the greatest accuracy and the highest specificity (area under the curve, 0.716; sensitivity, 40%; specificity, 92.1%). Conclusions: The lactate level at 48 h after admission was the most accurate predictor of UO with a high specificity in SAH patients. HIGHLIGHTSIn the unfavorable outcome group, initially increased lactate levels decreased to within the normal range for the first 24 h. Then, lactate levels slightly increased again to within the normal range for the next 24 h.The blood lactate level at each time point was greater in the unfavorable neurological outcome group than the favorable neurological outcome group.The lactate level at 48 h after admission was the most accurate predictor of unfavorable neurological outcomes in SAH patients.


Circulation | 2017

Critical Care Management Focused on Optimizing Brain Function After Cardiac Arrest

Ryuta Nakashima; Toru Hifumi; Kenya Kawakita; Tomoya Okazaki; Satoshi Egawa; Akihiko Inoue; Ryutaro Seo; Nobuhiro Inagaki; Yasuhiro Kuroda

The discussion of neurocritical care management in post-cardiac arrest syndrome (PCAS) has generally focused on target values used for targeted temperature management (TTM). There has been less attention paid to target values for systemic and cerebral parameters to minimize secondary brain damage in PCAS. And the neurologic indications for TTM to produce a favorable neurologic outcome remain to be determined. Critical care management of PCAS patients is fundamental and essential for both cardiologists and general intensivists to improve neurologic outcome, because definitive therapy of PCAS includes both special management of the cause of cardiac arrest, such as coronary intervention to ischemic heart disease, and intensive management of the results of cardiac arrest, such as ventilation strategies to avoid brain ischemia. We reviewed the literature and the latest research about the following issues and propose practical care recommendations. Issues are (1) prediction of TTM candidate on admission, (2) cerebral blood flow and metabolism and target value of them, (3) seizure management using continuous electroencephalography, (4) target value of hemodynamic stabilization and its method, (5) management and analysis of respiration, (6) sedation and its monitoring, (7) shivering control and its monitoring, and (8) glucose management. We hope to establish standards of neurocritical care to optimize brain function and produce a favorable neurologic outcome.


American Journal of Emergency Medicine | 2015

Successful management of heat stroke associated with multiple-organ dysfunction by active intravascular cooling.

Hideyuki Hamaya; Toru Hifumi; Kenya Kawakita; Tomoya Okazaki; Kazutaka Kiridume; Natsuyo Shinohara; Yuko Abe; Koshiro Takano; Masanobu Hagiike; Yasuhiro Kuroda

Heat stroke is a life-threatening condition requiring immediate initiation of rapid and effective cooling. We report successful cooling with initial intravascular cooling use that rapidly achieved the target temperature with continued normothermia thereafter. A 39-year-old previously healthy man collapsed on a hot, humid day and presented with a disturbance of consciousness. On initial examination, Glasgow Coma Scale score was 6/15, and his body temperature was 40.7°C. He was therefore intubated, and fluid resuscitation was initiated. A Cool Line catheter (Asahi KASEI ZOLL Medical, Tokyo, Japan) was inserted, and aggressive cooling was started using the intravascular balloon-catheter system (The Thermogard XP system; Asahi KASEI ZOLL Medical) within 32 minutes of arrival. His core temperature reached 38.8°C after 17 minutes of intravascular cooling at an average cooling rate of 0.10°C/min. Further investigation revealed impaired liver function and renal failure. His hemodynamic condition was stabilized, and no vasoactive agents were administrated during hospitalization. The cooling catheter was removed on day 2 of admission, and no bleeding, infection, or thrombosis associated with catheter placement was observed. Blood and urine cultures remained negative. Extubation was performed on day 3, and he was discharged on day 5 without further complication or sequelae. It is essential in the treatment of heat stroke to cool as quickly as possible and to provide cardiovascular support. In patients with severe heat stroke and multiple-organ dysfunction, initial use of the active intravascular cooling technique is warranted for aggressive cooling.


Acute medicine and surgery | 2016

Successful treatment of non-convulsive status epilepticus diagnosed using bedside monitoring by a combination of amplitude-integrated and two-channel simplified electroencephalography

Satoshi Egawa; Toru Hifumi; Kenya Kawakita; Arisa Manabe; Hikari Matumura; Tomoya Okazaki; Hideyuki Hamaya; Natuyo Shinohara; Hajime Shishido; Koshiro Takano; Yuko Abe; Masanobu Hagiike; Yasuhiro Kuroda

A 66‐year‐old man developed disturbed consciousness and right hemiparesis with transient convulsions in the right arm. Bedside monitoring using a combination of amplitude‐integrated electroencephalography and two‐channel simplified electroencephalography revealed intermittent episodes of 1–3 Hz δ waves lasting for approximately 5 min, consistent with non‐convulsive status epilepticus. Fosphenytoin (22.5 mg/kg/day) and levetiracetam (1,000 mg) prevented right arm convulsions but did not restore consciousness. The two‐channel simplified electroencephalography also showed an intermittent periodic δ wave pattern in the Fp1‐C3 channel. Conventional electroencephalography revealed a polymorphic δ activity that was abolished by 2.5 mg diazepam, thus confirming the diagnosis of non‐convulsive status epilepticus.


Journal of Critical Care | 2018

Association between dexmedetomidine use and neurological outcomes in aneurysmal subarachnoid hemorrhage patients: A retrospective observational study

Tomoya Okazaki; Toru Hifumi; Kenya Kawakita; Hajime Shishido; Daisuke Ogawa; Masanobu Okauchi; Atsushi Shindo; Masahiko Kawanishi; Keisuke Miyake; Takashi Tamiya; Yasuhiro Kuroda

Purpose: Recent studies in animal subarachnoid hemorrhage (SAH) models have reported that dexmedetomidine (DEX) use demonstrates significantly better neurological outcomes. This study aimed to evaluate whether DEX use is associated with favorable neurological outcomes (FO) in SAH patients. Materials and methods: We retrospectively reviewed all SAH patients between 2009 and 2017. We calculated the total dosage of DEX administered for the first 24 h after admission. All patients were classified into no use, low dosage, and standard dosage group. Multivariate analysis was performed to clarify the association between DEX use and FO (modified Ranking Scale score of 0–2 at hospital discharge). Results: There were 161 patients with 55.3% of FO. On univariate analysis, there were significant differences with regard to age, Hunt and Kosnik (H&K) grade, and DEX use. Multivariate analysis showed that age, H&K grade, and low dosage DEX (rather than no use) (odds ratio (OR) 3.17; 95% confidence interval (CI), 1.24–8.53; p = 0.02) were significantly associated with FO. However, standard dosage DEX was not a significant factor (OR, 0.75; 95% CI, 0.25–2.16; p = 0.59). Conclusions: Low dosage DEX during the first 24 h after admission was associated with FO in SAH patients. HighlightsLow dosage dexmedetomidine was associated with favorable neurological outcomes.Low dosage dexmedetomidine showed rapid clearance of blood lactate levels.The incidence of adverse events increased with the increased use of dexmedetomidine.


World journal of emergency medicine | 2016

Invasive group B streptococcal infection in a patient with post splenectomy for hypersplenism secondary to liver cirrhosis and portal hypertension

Tomoya Okazaki; Toru Hifumi; Arisa Manabe; Hikari Matsumura; Satoshi Egawa; Hideyuki Hamaya; Nastuyo Shinohara; Koshiro Takano; Hajime Shishido; Yuko Abe; Kenya Kawakita; Masanobu Hagiike; Yasuhiro Kuroda

BACKGROUND Splenectomy in patients with liver cirrhosis (LC) is expected to become more common owing to its efficacy on portal hemodynamics. In this report we describe an alarming case of group B streptococcus (GBS) infection after splenectomy in a patient with LC. METHODS A 72-year-old woman with a history of LC was admitted to our emergency department because of respiratory failure. The patient had received left lateral segmentectomy of the liver and splenectomy three months before admission. Pulmonary examination revealed significant wheezing during inspiration and expiration, but no crackles and stridor. Chest radiography and CT showed no infiltrates. A presumptive diagnosis of bronchial asthma caused by upper respiratory infection was made. Four days after admission, GBS infection was confirmed by blood culture and penicillin G was administered. Antibiotics were given intravenously for a total of 12 days. RESULTS The patient was discharged on the 12th day after admission. CONCLUSIONS Although efficacy of splenectomy in patients with LC has been reported, immune status should be evaluated for a longer period. Patients who have undergone splenectomy are highly susceptible to bacteria; moreover, LC itself is an independent risk factor for mortality in patients with sepsis. Since prophylaxis against GBS has not been established, immediate action should be taken. Emergency physicians should be aware of invasive GBS infection in the context of the critical risk factors related to splenectomy and LC, particularly the expected increase of splenectomy performed in LC patients.


Journal of intensive care | 2015

Indication for mild therapeutic hypothermia based on an initial Glasgow Coma Scale motor score

Toru Hifumi; Kenya Kawakita; Tomoya Okazaki; Satoshi Egawa; Yutaka Kondo; Tomoaki Natsukawa; Hirotaka Sawano

Although neurological evaluation using the Glasgow Coma Scale motor score is mandatory for post-cardiac arrest patients, further study is required to determine if this score can be used as an indicator for mild therapeutic hypothermia. Although the current study conducted by Natsukawa et al. presents interesting data, there are some critical issues regarding study design, selection bias, and interpretation of study results that should be pointed out.

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