Yoshiaki Okada

Bio: Yoshiaki Okada is an academic researcher from National Defense Medical College. The author has contributed to research in topics: Cardiopulmonary resuscitation & Resuscitation. The author has an hindex of 29, co-authored 114 publications receiving 2183 citations.

Early diagnosis of hypovolemic shock by sonographic measurement of inferior vena cava in trauma patients.

Abstract: Background:The diameter of the inferior vena cava in trauma patients may be useful for evaluating hypovolemia.Methods:Between June 2003 and September 2003, 35 injured patients transferred to the authors’ hospital were prospectively investigated. They were divided into two groups: a shock group (n =

Hypovolemic shock evaluated by sonographic measurement of the inferior vena cava during resuscitation in trauma patients.

Abstract: Background:Inferior vena cava (IVC) diameter immediately after fluid resuscitation has not yet been investigated in trauma patients with shock on arrival.Methods:Between June 2004 and May 2005, 30 trauma patients with hemorrhagic shock were prospectively investigated. Using ultrasound, we measured m

A quantitative analysis of head injury using T2*-weighted gradient-echo imaging.

Abstract: Background: T2 * -weighted gradient-echo imaging (T2 * -GE) is useful for detecting small hemorrhages. Methods: Thirty-four patients were prospectively examined, first by magnetic resonance imaging (1.5 T) and then by T2-weighted fast spin echo (T2-FSE) and T2 * -GE. Thereafter, the correlations between the T2-FSE or T2 * -GE findings and the clinical or computed tomography findings were analyzed. Results: The number of lesions detected by T2 * -GE was 14.5 ± 16.3 (mean ± SD, n = 34), which was significantly (p < 0.001) greater than that detected by T2-FSE (5.6 ± 5.6, n = 34). The findings of T2 * -GE correlated positively with both the duration of unconsciousness (R 2 = 0.74, p < 0.0001) and with Glasgow Outcome Scale (R 2 = 0.81, p < 0.0001), whereas those of T2-FSE did not show any significant correlation. T2 * -GE imaging could also detect all areas responsible for focal neurologic signs 1 month after injury, whereas T2-FSE imaging detected only 22 of 33 such signs. Conclusion: T2*-GE was found to be useful for evaluating the clinical symptoms of head injury.

Treatment of Comatose Survivors of Out-of-Hospital Cardiac Arrest with Induced Hypothermia

Abstract: Background Cardiac arrest outside the hospital is common and has a poor outcome. Studies in laboratory animals suggest that hypothermia induced shortly after the restoration of spontaneous circulation may improve neurologic outcome, but there have been no conclusive studies in humans. In a randomized, controlled trial, we compared the effects of moderate hypothermia and normothermia in patients who remained unconscious after resuscitation from out-of-hospital cardiac arrest. Methods The study subjects were 77 patients who were randomly assigned to treatment with hypothermia (with the core body temperature reduced to 33°C within 2 hours after the return of spontaneous circulation and maintained at that temperature for 12 hours) or normothermia. The primary outcome measure was survival to hospital discharge with sufficiently good neurologic function to be discharged to home or to a rehabilitation facility. Results The demographic characteristics of the patients were similar in the hypothermia and normotherm...

Mild therapeutic hypothermia to improve the neurologic outcome after cardiac arrest

Abstract: Background: Cardiac arrest with widespread cerebral ischemia frequently leads to severe neurologic impairment. We studied whether mild systemic hypothermia increases the rate of neurologic recovery after resuscitation from cardiac arrest due to ventricular fibrillation. Methods: In this multicenter trial with blinded assessment of the outcome, patients who had been resuscitated after cardiac arrest due to ventricular fibrillation were randomly assigned to undergo therapeutic hypothermia (target temperature, 32°C to 34°C, measured in the bladder) over a period of 24 hours or to receive standard treatment with normothermia. The primary end point was a favorable neurologic outcome within six months after cardiac arrest; secondary end points were mortality within six months and the rate of complications within seven days. Results: Seventy-five of the 136 patients in the hypothermia group for whom data were available (55 percent) had a favorable neurologic outcome (cerebral-performance category, 1 [good recovery] or 2 [moderate disability]), as compared with 54 of 137 (39 percent) in the normothermia group (risk ratio, 1.40; 95 percent confidence interval, 1.08 to 1.81). Mortality at six months was 41 percent in the hypothermia group (56 of 137 patients died), as compared with 55 percent in the normothermia group (76 of 138 patients; risk ratio, 0.74; 95 percent confidence interval, 0.58 to 0.95). The complication rate did not differ significantly between the two groups. Conclusions: In patients who have been successfully resuscitated after cardiac arrest due to ventricular fibrillation, therapeutic mild hypothermia increased the rate of a favorable neurologic outcome and reduced mortality.

Treatment of comatose survivors of out-of-hospital cardiac arrest with induced hypothermia☆

Abstract: BACKGROUND Cardiac arrest outside the hospital is common and has a poor outcome. Studies in laboratory animals suggest that hypothermia induced shortly after the restoration of spontaneous circulation may improve neurologic outcome, but there have been no conclusive studies in humans. In a randomized, controlled trial, we compared the effects of moderate hypothermia and normothermia in patients who remained unconscious after resuscitation from out-of-hospital cardiac arrest. METHODS The study subjects were 77 patients who were randomly assigned to treatment with hypothermia (with the core body temperature reduced to 33 degrees C within 2 hours after the return of spontaneous circulation and maintained at that temperature for 12 hours) or normothermia. The primary outcome measure was survival to hospital discharge with sufficiently good neurologic function to be discharged to home or to a rehabilitation facility. RESULTS The demographic characteristics of the patients were similar in the hypothermia and normothermia groups. Twenty-one of the 43 patients treated with hypothermia (49 percent) survived and had a good outcome--that is, they were discharged home or to a rehabilitation facility--as compared with 9 of the 34 treated with normothermia (26 percent, P=0.046). After adjustment for base-line differences in age and time from collapse to the return of spontaneous circulation, the odds ratio for a good outcome with hypothermia as compared with normothermia was 5.25 (95 percent confidence interval, 1.47 to 18.76; P=0.011). Hypothermia was associated with a lower cardiac index, higher systemic vascular resistance, and hyperglycemia. There was no difference in the frequency of adverse events. CONCLUSIONS Our preliminary observations suggest that treatment with moderate hypothermia appears to improve outcomes in patients with coma after resuscitation from out-of-hospital cardiac arrest.

Part 9: Post-Cardiac Arrest Care: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care

Abstract: There is increasing recognition that systematic post–cardiac arrest care after return of spontaneous circulation (ROSC) can improve the likelihood of patient survival with good quality of life. This is based in part on the publication of results of randomized controlled clinical trials as well as a description of the post–cardiac arrest syndrome. 1–3 Post–cardiac arrest care has significant potential to reduce early mortality caused by hemodynamic instability and later morbidity and mortality from multiorgan failure and brain injury. 3,4 This section summarizes our evolving understanding of the hemodynamic, neurological, and metabolic abnormalities encountered in patients who are initially resuscitated from cardiac arrest. The initial objectives of post–cardiac arrest care are to ● Optimize cardiopulmonary function and vital organ perfusion. ● After out-of-hospital cardiac arrest, transport patient to an appropriate hospital with a comprehensive post–cardiac arrest treatment system of care that includes acute coronary interventions, neurological care, goal-directed critical care, and hypothermia. ● Transport the in-hospital post–cardiac arrest patient to an appropriate critical-care unit capable of providing comprehensive post–cardiac arrest care. ● Try to identify and treat the precipitating causes of the arrest and prevent recurrent arrest.