Masato Ueno

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.

Validation of a modified table to map the 1998 abbreviated injury scale to the 2008 scale and the use of adjusted severities

BACKGROUND The Abbreviated Injury Scale 2008 (AIS 2008) is the most recent injury coding system. A mapping table from a previous AIS 98 to AIS 2008 is available. However, AIS 98 codes that are unmappable to AIS 2008 codes exist in this table. Furthermore, some AIS 98 codes can be mapped to multiple candidate AIS 2008 codes with different severities. We aimed to modify the original table to adjust the severities and to validate these changes. METHODS We modified the original table by adding links from unmappable AIS 98 codes to AIS 2008 codes. We applied the original table and our modified table to AIS 98 codes for major trauma patients. We also assigned candidate codes with different severities the weighted averages of their severities as an adjusted severity. The proportion of cases whose injury severity scores (ISSs) were computable were compared. We also compared the agreement of the ISS and New ISS (NISS) between manually determined AIS 2008 codes (MAN) and mapped codes by using our table (MAP) with unadjusted or adjusted severities. RESULTS All and 72.3% of cases had their ISSs computed by our modified table and the original table, respectively. The agreement between MAN and MAP with respect to the ISS and NISS was substantial (intraclass correlation coefficient = 0.939 for ISS and 0.943 for NISS). Using adjusted severities, the agreements of the ISS and NISS improved to 0.953 (p = 0.11) and 0.963 (p = 0.007), respectively. CONCLUSION Our modified mapping table seems to allow more ISSs to be computed than the original table. Severity scores exhibited substantial agreement between MAN and MAP. The use of adjusted severities improved these agreements further.

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.