Hiroyuki Yokota

Evaluation of the safety and feasibility of resuscitative endovascular balloon occlusion of the aorta.

BACKGROUND Resuscitative endovascular balloon occlusion of the aorta (REBOA) is one of the ultimately invasive procedures for managing a noncompressive torso injury. Since it is less invasive than resuscitative open aortic cross-clamping, its clinical application is expected. METHODS We retrospectively evaluated the safety and clinical feasibility of REBOA (intra-aortic occlusion balloon, MERA, Tokyo, Japan) using the Seldinger technique to control severe hemorrhage. Of 5,230 patients admitted to our trauma center in Japan from 2007 to 2013, we included 24 who underwent REBOA primarily. The indications for REBOA were a pelvic ring fracture or hemoperitoneum with hemodynamically instability and impending cardiac arrest. Emergency hemostasis was performed during REBOA in all patients. RESULTS All 24 patients had a blunt injury, the median age was 59 (interquartile range, 41–71 years), the median Injury Severity Score (ISS) was 47 (interquartile range, 37–52), the 30-day survival rate was 29.2% (n = 7), and the median probability survival rate was 12.5%. Indications for REBOA were hemoperitoneum and pelvic ring fracture in 15 cases and overlap in 8 cases. In 10 cases of death, the balloon could not be deflated in 5 cases. In 19 cases in which the balloon was deflated, the median duration of aortic occlusion was shorter in survivors than in deaths (21 minutes vs. 35 minutes, p = 0.05). The mean systolic blood pressure was significantly increased by REBOA (from 53.1 [21] mm Hg to 98.0 [26.6] mm Hg, p < 0.01). There were three cases with complications (12.5%), one external iliac artery injury and two lower limb ischemias in which lower limb amputation was necessary in all cases. Acute kidney injury developed in all three cases, but failure was not persistent. CONCLUSION REBOA seems to be feasible for trauma resuscitation and may improve survivorship. However, the serious complication of lower limb ischemia warrants more research on its safety. LEVEL OF EVIDENCE Therapeutic/care management, level V.

Regional cerebral blood flow in delirium patients

Abstract The purpose of the present paper was to determine the possible mechanism of delirium by using xenon‐enhanced computed tomography to measure the regional cerebral blood flow (rCBF) of the patients both during delirium and after improvement from delirium. The rCBF measurements of the frontal, temporal and occipital cortex during delirium ranged from 31.4 to 39.6 mL/100 g per min; the rCBF of the thalamus and basal ganglia ranged from 47.5 to 52.4 mL/100 g per min. After recovery from delirium the rCBF of both areas returned to normal. The findings that reduced rCBF during delirium becomes normal once delirium improves suggest that a possible cause of delirium may be the cerebral hypoperfusion.

Validation of extravascular lung water measurement by single transpulmonary thermodilution: human autopsy study

IntroductionGravimetric validation of single-indicator extravascular lung water (EVLW) and normal EVLW values has not been well studied in humans thus far. The aims of this study were (1) to validate the accuracy of EVLW measurement by single transpulmonary thermodilution with postmortem lung weight measurement in humans and (2) to define the statistically normal EVLW values.MethodsWe evaluated the correlation between pre-mortem EVLW value by single transpulmonary thermodilution and post-mortem lung weight from 30 consecutive autopsies completed within 48 hours following the final thermodilution measurement. A linear regression equation for the correlation was calculated. In order to clarify the normal lung weight value by statistical analysis, we conducted a literature search and obtained the normal reference ranges for post-mortem lung weight. These values were substituted into the equation for the correlation between EVLW and lung weight to estimate the normal EVLW values.ResultsEVLW determined using transpulmonary single thermodilution correlated closely with post-mortem lung weight (r = 0.904, P < 0.001). A linear regression equation was calculated: EVLW (mL) = 0.56 × lung weight (g) - 58.0. The normal EVLW values indexed by predicted body weight were approximately 7.4 ± 3.3 mL/kg (7.5 ± 3.3 mL/kg for males and 7.3 ± 3.3 mL/kg for females).ConclusionsA definite correlation exists between EVLW measured by the single-indicator transpulmonary thermodilution technique and post-mortem lung weight in humans. The normal EVLW value is approximately 7.4 ± 3.3 mL/kg.Trial registrationUMIN000002780.

Significance of magnetic resonance imaging in acute head injury.

One hundred seventy-seven patients who had incurred head trauma were studied with magnetic resonance imaging (MRI). Patients varied from those with mild injury without any focal neurological deficit to those with severe injury with post-traumatic coma. Altogether, 177 lesions were demonstrated by MRI in 123 of 177 patients within 3 days of injury using T2-weighted (SE2000/40,2000/111) and T1-weighted (IR1500/500/40) multislice sequences. In contrast, computerized tomography (CT) demonstrated 103 lesions in 90 patients. MRI was superior to CT in the diagnosis of nonhemorrhagic contusions demonstrated as a high-intensity area on T2-weighted imaging. MRI provided some information to evaluate the severity of diffuse axonal injury or to predict delayed traumatic intracerebral hematoma (DTICH).

Implementation of the Fifth Link of the Chain of Survival Concept for Out-of-Hospital Cardiac Arrest

Background— The American Heart Association 2010 resuscitation guidelines recommended adding a fifth link (multidisciplinary postresuscitation care in a regional center) to the previous 4 in the chain of survival concept for out-of-hospital cardiac arrest. Our study aimed to determine the effectiveness of this fifth link. Methods and Results— This multicenter prospective cohort study involved all eligible out-of-hospital cardiac arrest patients in the Aizu region (n=1482, suburban/rural, Fukushima, Japan). Proportions of favorable neurological outcomes were evaluated before (January 2006–April 2008) and after (January 2009–December 2010) the implementation of the fifth link. After implementation, all patients were transported directly from the field to the tertiary-level hospital or secondarily from an outlying hospital to the tertiary-level hospital after restoration of circulation. The tertiary hospital provided intensive postresuscitation care, including appropriate hemodynamic and respiratory management, therapeutic hypothermia, and percutaneous coronary intervention. One-month survival with a favorable neurological outcome among all patients treated by emergency medical services providers improved significantly after implementation (4 of 770 [0.5%] versus 21 of 712 [3.0%]; P<0.001). The adjusted odds ratios of favorable neurological outcome were 0.9 (95% confidence interval, 0.7–1.1) for early access to emergency medical care, 3.1 (95% confidence interval, 0.7–14.2) for bystander resuscitation, 14.7 (95% confidence interval, 3.2–67.0) for early defibrillation, 1.0 (95% confidence interval, 1.0–1.1) for early advanced life support, and 7.8 (95% confidence interval, 1.6–39.0) for the fifth link. Conclusion— The proportion of out-of-hospital cardiac arrest patients with a favorable neurological outcome improved significantly after the implementation of the fifth link, which may be an independent predictor of outcome. Clinical Trial Registration— URL: http://www.apps.who.int/trialsearch. Unique identifier: UMIN000001607.

Comparison of Neurological Outcome between Tracheal Intubation and Supraglottic Airway Device Insertion of Out-of-hospital Cardiac Arrest Patients: A Nationwide, Population-based, Observational Study

BACKGROUND The effect of prehospital use of supraglottic airway devices as an alternative to tracheal intubation on long-term outcomes of patients with out-of-hospital cardiac arrest is unclear. STUDY OBJECTIVES We compared the neurological outcomes of patients who underwent supraglottic airway device insertion with those who underwent tracheal intubation. METHODS We conducted a nationwide population-based observational study using a national database containing all out-of-hospital cardiac arrest cases in Japan over a 3-year period (2005-2007). The rates of neurologically favorable 1-month survival (primary outcome) and of 1-month survival and return of spontaneous circulation before hospital arrival (secondary outcomes) were examined. Multiple logistic regression analyses were performed to adjust for potential confounders. Advanced airway devices were used in 138,248 of 318,141 patients, including an endotracheal tube (ETT) in 16,054 patients (12%), a laryngeal mask airway (LMA) in 34,125 patients (25%), and an esophageal obturator airway (EOA) in 88,069 patients (63%). RESULTS The overall rate of neurologically favorable 1-month survival was 1.03% (1426/137,880). The rates of neurologically favorable 1-month survival were 1.14% (183/16,028) in the ETT group, 0.98% (333/34,059) in the LMA group, and 1.04% (910/87,793) in the EOA group. Compared with the ETT group, the rates were significantly lower in the LMA group (adjusted odds ratio 0.77, 95% confidence interval [CI] 0.64-0.94) and EOA group (adjusted odds ratio 0.81, 95% CI 0.68-0.96). CONCLUSIONS Prehospital use of supraglottic airway devices was associated with slightly, but significantly, poorer neurological outcomes compared with tracheal intubation, but neurological outcomes remained poor overall.

Cerebral endothelial injury in severe head injury: the significance of measurements of serum thrombomodulin and the von Willebrand factor.

Thrombomodulin (TM), which is located in the surface of the endothelium in the arteries, veins, and capillaries of major organs such as the brain, lungs, liver, kidneys, skeletal muscles, and gastrointestinal tract, is one of several indicators of endothelial injury. Von Willebrand factor (vWf), which is synthesized by endothelial cells, is also an endothelial specific glycoprotein. The serum level of vWf increases in response to various stimuli without endothelial injury. An elevated serum level of vWf may suggest endothelial activation in severe head injury. We hypothesize that the degree of cerebral endothelial activation or injury depends on the type of head injury and that measuring the TM and vWf is useful for predicting delayed traumatic intracerebral hematoma (DTICH), produced by weakness of the vessel wall, occuring either as a direct or indirect effect of head injury. The values of vWf in focal brain injury (ranging from 332.5 +/- 52.8% to 361.7 +/- 86.2%) were significantly higher than those in diffuse axonal injury from 2 h to 7 days after the injury occurred (ranging from 201.6 +/- 59.5% to 242.5 +/- 51.7%). The serum level of TM in focal brain injury (ranging from 3.84 +/- 1.54 to 4.12 +/- 1.46 U/mL) was higher than that in diffuse axonal injury (ranging from 2.96 +/- 0.63 to 3.67 +/- 1.70 U/mL), but these differences were not statistically significant. In patients with DTICH, TM was significantly higher than in patients without DTICH (p < 0.01). The results of our study demonstrate that the degree of endothelial activation in focal brain injury was significantly higher than in diffuse brain injury. In addition, the serum level of TM in patients with DTICH was significantly higher than in patients without DTICH. These findings suggest that cerebral tissue injury is often accompanied by cerebral endothelial activation, and that these two phenomena should be distinguished from each other. The levels of serum TM and vWf appear to be good indicators of the cerebral endothelial injury and of endothelial activation in severe head injury.

The precision of PiCCO® measurements in hypothermic post-cardiac arrest patients

The aim of the present study was to determine the precision of the PiCCO® system for post‐cardiac arrest patients who underwent therapeutic hypothermia. The precision of the measurements for cardiac output, global end‐diastolic volume, extravascular lung water and the pulmonary vascular permeability index was assessed using the least significant change; this was regarded as precise when less than 15%. A total of 462 measurement sets were prospectively performed on 88 patients following successful resuscitation after cardiac arrest. Using the mean value of three injections for a measurement, the least significant change for the cardiac output, global end‐diastolic volume, extravascular lung water and pulmonary vascular permeability index measurements were found to be 7.8%, 8.5%, 7.8% and 12.1%, respectively. No significant differences between hypothermia (n = 150) and non‐hypothermia (n = 312) were found. The PiCCO‐derived variables were found to be precise for post‐cardiac arrest patients even under conditions of varying body temperature.

Coagulofibrinolytic changes in patients with disseminated intravascular coagulation associated with post-cardiac arrest syndrome― Fibrinolytic shutdown and insufficient activation of fibrinolysis lead to organ dysfunction

INTRODUCTION Post-cardiac arrest syndrome (PCAS) is often associated with disseminated intravascular coagulation (DIC), thus leading to the development of multiple organ dysfunction syndrome (MODS). The aim of this study was to examine the pathophysiological relationships between coagulation, fibrinolysis and fibrinolytic shutdown by evaluating the levels of coagulofibrinolytic markers, including soluble fibrin, thrombin-activatable fibrinolysis inhibitor (TAFI), tissue plasminogen activator-plasminogen activator inhibitor-1 complex (tPAIC), plasmin-alpha2 plasmin inhibitor complex (PPIC), neutrophil elastase and fibrin degradation product by neutrophil elastase (EXDP). MATERIALS AND METHODS Fifty-two resuscitated patients were divided into two groups: 22 DIC and 30 non-DIC patients. RESULTS The levels of soluble fibrin, PPIC, tPAIC, EXDP and neutrophil elastase in the DIC patients with PCAS were significantly higher than those observed in the non-DIC patients. The values of the tPAIC and JAAM DIC scores were found to be independent predictors of increased SOFA scores in the DIC patients. The MODS patients demonstrated significantly higher levels of soluble fibrin and tPAIC; however, the levels of TAFI and EXDP were identical between the patients with and without MODS. In addition, positive correlations were observed between the levels of tPAIC and EXDP in the patients with non-MODS; however, no correlations were observed between these markers in the MODS patients. CONCLUSIONS Thrombin activation and fibrinolytic shutdown play important roles in the development of organ dysfunction in PCAS patients. Neutrophil elastase-mediated fibrinolysis cannot overcome the fibrinolytic shutdown that occurs in DIC patients with PCAS, thus resulting in the development of MODS.

Optimal range of global end-diastolic volume for fluid management after aneurysmal subarachnoid hemorrhage: a multicenter prospective cohort study.

Objectives:Limited evidence supports the use of hemodynamic variables that correlate with delayed cerebral ischemia or pulmonary edema after aneurysmal subarachnoid hemorrhage. The aim of this study was to identify those hemodynamic variables that are associated with delayed cerebral ischemia and pulmonary edema after subarachnoid hemorrhage. Design:A multicenter prospective cohort study. Setting:Nine university hospitals in Japan. Patients:A total of 180 patients with aneurysmal subarachnoid hemorrhage. Interventions:None. Measurements and Main Results:Patients were prospectively monitored using a transpulmonary thermodilution system in the 14 days following subarachnoid hemorrhage. Delayed cerebral ischemia was developed in 35 patients (19.4%) and severe pulmonary edema was developed in 47 patients (26.1%). Using the Cox proportional hazards model, the mean global end-diastolic volume index (normal range, 680–800 mL/m2) was the independent factor associated with the occurrence of delayed cerebral ischemia (hazard ratio, 0.74; 95% CI, 0.60–0.93; p = 0.008). Significant differences in global end-diastolic volume index were detected between the delayed cerebral ischemia and non–delayed cerebral ischemia groups (783 ± 25 mL/m2 vs 870 ± 14 mL/m2; p = 0.007). The global end-diastolic volume index threshold that best correlated with delayed cerebral ischemia was less than 822 mL/m2, as determined by receiver operating characteristic curves. Analysis of the Cox proportional hazards model indicated that the mean global end-diastolic volume index was the independent factor that associated with the occurrence of pulmonary edema (hazard ratio, 1.31; 95% CI, 1.02–1.71; p = 0.03). Furthermore, a significant positive correlation was identified between global end-diastolic volume index and extravascular lung water (r = 0.46; p < 0.001). The global end-diastolic volume index threshold that best correlated with severe pulmonary edema was greater than 921 mL/m2. Conclusions:Our findings suggest that global end-diastolic volume index impacts both delayed cerebral ischemia and pulmonary edema after subarachnoid hemorrhage. Maintaining global end-diastolic volume index slightly above normal levels has promise as a fluid management goal during the treatment of subarachnoid hemorrhage.