Yasuaki Mizushima

Estradiol administration after trauma-hemorrhage improves cardiovascular and hepatocellular functions in male animals.

ObjectiveTo determine whether female sex steroids have any salutary effects on the depressed cardiovascular and hepatocellular functions following trauma and hemorrhage in male animals. Summary Background DataStudies indicate that gender difference exists in the immune and cardiovascular responses to trauma-hemorrhage, and that male sex steroids appear to be responsible for producing immune and organ dysfunction, but it remains unknown if female sex steroids produce any salutary effects on the depressed cellular and organ functions in males following trauma and hemorrhage. MethodAdult male Sprague-Dawley rats underwent a midline laparotomy (i.e., trauma induction), and were bled to and maintained at a mean arterial pressure of 40 mmHg until 40% of the maximum bleed-out volume was returned in the form of Ringer’s lactate (RL). Animals were then resuscitated with RL at 4 times the shed blood over 60 minutes. 17&bgr;-Estradiol (50 &mgr;g/kg) or an equal volume of vehicle was injected subcutaneously 15 minutes before the end of resuscitation. The maximal rate of ventricular pressure increase or decrease (±dP/dtmax), cardiac output, and hepatocellular function (i.e., maximal velocity and overall efficiency of in vivo indocyanine green clearance) were assessed at 24 hours after hemorrhage and resuscitation. Plasma levels of interleukin (IL)-6 were also measured. ResultsLeft ventricular performance, cardiac output, and hepatocellular function decreased significantly at 24 hours after trauma-hemorrhage and resuscitation. Plasma levels of IL-6 were elevated. Administration of 17&bgr;-estradiol significantly improved cardiac performance, cardiac output, and hepatocellular function, and attenuated the increase in plasma IL-6 levels. ConclusionAdministration of estrogen appears to be a useful adjunct for restoring cardiovascular and hepatocellular functions after trauma-hemorrhage in male rats.

Should normothermia be restored and maintained during resuscitation after trauma and hemorrhage

BACKGROUND Although hypothermia often occurs after trauma and has protective effects during ischemia and organ preservation, it remains unknown whether maintenance of hypothermia or restoring the body temperature to normothermia during resuscitation has any deleterious or beneficial effects on heart performance and organ blood flow after trauma-hemorrhage. METHODS Male rats underwent laparotomy (i.e., induced trauma) and were exsanguinated to and maintained at a mean arterial pressure of 40 mm Hg until 40% of the maximum shed volume was returned in the form of Ringers lactate. Body temperature decreased from approximately 36.5 degrees C to below 32 degrees C. The animals were then resuscitated with four times the volume of maximal bleedout with Ringers lactate. In one group, body temperature was rewarmed to 37 degrees C during resuscitation. In another group, body temperature was maintained at hypothermia (32 degrees C) for 4 hours after resuscitation. In an additional group, the body temperature was kept at 37 degrees C during hemorrhage as well as during resuscitation. Left ventricle performance parameters such as maximal rate of left ventricular pressure increase and decrease (+/-dP/dt(max)) were measured up to 4 hours. Cardiac output and regional blood flow were determined by radioactive microspheres at 4 hours after the completion of resuscitation. RESULTS The maintenance of normothermia during hemor. rhage or prolonged hypothermia after resuscitation depressed the left ventricular performance parameters, cardiac output, and regional blood flow in various organs. Rewarming the body to normothermia during resuscitation, however, significantly increased heart performance, cardiac output (from hypothermia 16.2 +/- 1.4 to 22.3 +/- 1.4 mL/min per 100 g body weight,p < 0.05) and total hepatic blood flow (from hypothermia 117.5 +/- 5.3 to 166.0 +/- 9.3 mL/min per 100 g tissue, p < .05). CONCLUSION Our data indicate that restoration of normothermia during resuscitation improves cardiac function and hepatic blood flow compared with hypothermia.

Fever in trauma patients: friend or foe?

BACKGROUND In trauma patients, elevated body temperature is a common and noninfective procedure soon after injury. We hypothesized that the absence of this febrile response is associated with failure to meet metabolic demands and results in adverse outcomes. METHODS We collected retrospective data of 253 consecutive trauma patients admitted to the intensive care unit during a 3-year period. Patients were stratified according to their daily maximum body temperature from days 1 to 10 (Tmax 1-10): no fever (<37.5 degrees C), low fever (37.5-38.4 degrees C), moderate fever (38.5-39.0 degrees C), and high fever (>39.0 degrees C). The area under the curve (AUC) of core temperature during the first 24 hours after admission was calculated for each patient at a baseline of 36 degrees C. The infection and mortality rates were measured. RESULTS Sixty-three patients (24.9%) developed an infection, and the overall mortality was 7.5% (19 patients). Patients with no Tmax 1 and a low or high Tmax 4 to 10 had a significantly high infection rate; those with no fever on days 1 and 2 had a significantly high mortality rate. A low AUC was also associated with significantly higher infection and mortality rates. Multiple logistic regression analysis controlled for age, injury severity score, Tmax 1, AUC, initial temperature at admission, and time taken to reach 36 degrees C (if hypothermia was present) revealed that age, injury severity score, low AUC (odds ratio, 0.96; 95% confidence interval, 0.94-0.99; p = 0.002), and initial temperature were independent predictors of infection. Age and lower AUC (odds ratio, 0.87; 95% confidence interval, 0.81-0.92; p < 0.001) were both predictors of mortality. CONCLUSIONS A febrile response until day 4 after injury did not increase morbidity, and a low AUC is independently associated with adverse outcomes. These findings show that a nonfebrile response soon after injury results in poor prognosis.

Discrepancy Between Heart Rate and Makers of Hypoperfusion Is a Predictor of Mortality in Trauma Patients

BACKGROUND Tachycardia is an important early sign of shock in trauma. Although the base deficit (BD) and lactate are indicative of hypoperfusion and known to predict mortality, some cases show a discrepancy between heart rate (HR) and BD or lactate; such cases have poor prognosis. The objective of this study was to examine whether lack of tachycardia after hypoperfusion is associated with increased mortality. METHODS Retrospective data were collected on 1,742 adult trauma patients. Mortality was compared with different levels of BD, lactate, and HR on admission. Multivariate logistic regression was used to identify significant risk factors for mortality. RESULTS Significantly increased mortality was observed in patients with hypoperfusion (BD less than -5 mmol/L or lactate more than 5 mmol/L). Among these patients, those with a normal HR (<80 bpm) were associated with a higher mortality rate than those with tachycardia (HR, 80-100 or>100 bpm). However, systolic blood pressure (SBP) was not significantly different between the different HR groups. Logistic regression analysis revealed that discrepancy between HR and indicators of hypoperfusion (Dis BD: BD less than -5 mmol/L and HR less than 80 bpm; or Dis lac: lactate more than 5 mmol/L and HR less than 80 bpm) are independent predictors of mortality after controlling for age, SBP, Injury Severity Score, head Abbreviated Injury Scale, HR, and BD or lactate (Dis BD: odds ratio, 2.67; 95% confidence interval, 1.07-6.61; p<0.05 and Dis lac: odds ratio, 4.11; 95% confidence interval, 1.57-10.74; p<0.01, respectively). CONCLUSIONS The lack of tachycardia in the presence of hypoperfusion is associated with poor prognosis independent of injury severity, SBP, and head injury. A discrepancy between HR and indicators of hypoperfusion could be considered as a predictor of mortality in trauma patients.

Duodenal Disruption Diagnosed 5 Days After Blunt Trauma in a 2-Year-Old Child : Report of a Case

Blunt duodenal injury in children is uncommon and diagnosis is often delayed because of its retroperitoneal location. Both diagnosis and treatment are difficult. We report the case of a 2-year-old boy whose trauma injury was not reported for 5 days. His vital signs were stable, but he was vomiting bile-stained fluid and his stools were white. The third portion of the duodenum was completely disrupted, and was repaired by pyloric exclusion with duodenal and bile duct drainage. The child recovered uneventfully. We discuss the diagnostic strategies and therapeutic measures for this type of injury.

Development of a prehospital vital signs chart sharing system.

OBJECTIVE Physiological parameters are crucial for the caring of trauma patients. There is a significant loss of prehospital vital signs data of patients during handover between prehospital and in-hospital teams. Effective strategies for reducing the loss remain a challenging research area. We tested whether the newly developed electronic automated prehospital vital signs chart sharing system would increase the amount of prehospital vital signs data shared with a remote trauma center prior to hospital arrival. METHODS Fifty trauma patients, transferred to a level I trauma center in Japan, were studied. The primary outcome variable was the number of prehospital vital signs shared with the trauma center prior to hospital arrival. RESULTS The prehospital vital signs chart sharing system significantly increased the number of prehospital vital signs, including blood pressure, heart rate, and oxygen saturation, shared with the in-hospital team at a remote trauma center prior to patient arrival at the hospital (P < .0001). There were significant differences in prehospital vital signs during ambulance transfer between patients who had severe bleeding and non-severe bleeding within 24 hours after injury onset. CONCLUSIONS Vital signs data collected during ambulance transfer via patient monitors could be automatically converted to easily visible patient charts and effectively shared with the remote trauma center prior to hospital arrival. The prehospital vital signs chart sharing system increased the number of precise vital signs shared prior to patient arrival at the hospital, which can potentially contribute to better trauma care without increasing labor and reduce information loss during clinical handover.

Fluid resuscitation of trauma patients: How much fluid is enough to determine the patient's response?

The topic of damage control resuscitation has become increasingly popular during the last several years [1-4]. This topic involves several key concepts that include permissive hypotension (restrictive fluid resuscitation), which is a strategy that restricts fluid use before any bleeding is controlled to avoid excessive blood loss. However, the related studies have mainly evaluated patients with penetrating injury and in the pre-hospital setting. Therefore, it is unclear whether this approach provides benefits in cases of blunt trauma or in-hospital setting. In addition, patients with hypotension should be rapidly stabilizedwith amoderate fluid infusion tomaintain tissue perfusion. Therefore, the American College of Surgeons Advanced Trauma Life Support training program emphasizes a “balanced” approach to ensure adequate tissue perfusion andminimize the risk of re-bleeding by avoiding inadequate or excessive fluid administration [5]. The Advanced Trauma Life Support and Japan Advanced Trauma Evaluation and Care guidelines both recommend an initial rapid infusion of fluid (1−2 L) as a diagnostic procedure for patients who have experienced traumaor hemorrhage [5,6]. However, the appropriate volume of fluid infusion has not been clearly defined, despite the patients responses to the initial fluid resuscitation being critical to selecting an appropriate therapeutic strategy. Therefore, this study aimed to determine the optimal volume of fluid infusion during the initial resuscitation of patients who had experienced trauma and hypotension.

Radiological classification of retroperitoneal hematoma resulting from lumbar vertebral fracture

PurposeLumbar vertebral fracture (LVF) infrequently produces massive retroperitoneal hematoma (RPH). This study aimed to systematically review the clinical and radiographic characteristics of RPH resulting from LVF.MethodsFor 193 consecutive patients having LVF who underwent computed tomography (CT), demographic data, physiological conditions, and outcomes were reviewed from their medical records. Presence or absence of RPH, other bone fractures, or organ/vessel injury was evaluated in their CT images, and LVF or RPH, if present, was classified according to either the Orthopaedic Trauma Association classification or the concept of interfascial planes.ResultsRPH resulting only or dominantly from LVF was found in 66 (34.2%) patients, whereas among the others, 64 (33.2%) had no RPH, 38 (19.7%) had RPH from other injuries, and 25 (13.0%) had RPH partly attributable to LVF. The 66 RPHs resulting only or dominantly from LVF were radiologically classified into mild subtype of minor median (n = 35), moderate subtype of lateral (n = 11), and severe subtypes of central pushing-up (n = 13) and combined (n = 7). Of the 20 patients with severe subtypes, 18 (90.0%) were in hemorrhagic shock on admission, and 6 (30.0%) were clinically diagnosed as dying due to uncontrollable RPH resulting from vertebral body fractures despite no anticoagulant medication.ConclusionsLVF can directly produce massive RPH leading to hemorrhagic death. A major survey of such pathology should be conducted to establish appropriate diagnosis and treatment.

Thoracotomy for blunt chest trauma: is chest tube output a useful criterion?

The aim of this study was to determine whether the traditional criteria of chest tube output are useful indicators for urgent thoracotomy in patients with blunt chest trauma.

Severe pancreatoduodenal injury

A 30‐year‐old male involved in a traffic accident was brought to our hospital. He was in shock with a rigid abdomen, and a computed tomography scan showed severe pancreatoduodenal injury. He was successfully treated with damage control surgery consisting of peripancreatic packing at the initial surgery followed by a two‐stage pancreaticoduodenectomy.