Impact of emergency medical helicopter transport directly to a university hospital trauma center on mortality of severe blunt trauma patients until discharge.

INTRODUCTION: The benefits of transporting severely injured patients by helicopter remain controversial. This study aimed to analyze the impact on mortality of helicopter compared to ground transport directly from the scene to a University hospital trauma center. METHODS: The French Intensive Care Research for Severe Trauma cohort study enrolled 2,703 patients with severe blunt trauma requiring admission to University hospital intensive care units within 72 hours. Pre-hospital and hospital clinical data, including the mode of transport, (helicopter (HMICU) versus ground (GMICU), both with medical teams), were recorded. The analysis was restricted to patients admitted directly from the scene to a University hospital trauma center. The main endpoint was mortality until ICU discharge. RESULTS: Of the 1,958 patients analyzed, 74% were transported by GMICU, 26% by HMICU. Median injury severity score (ISS) was 26 (interquartile range (IQR) 19 to 34) for HMICU patients and 25 (IQR 18 to 34) for GMICU patients. Compared to GMICU, HMICU patients had a higher median time frame before hospital admission and were more intensively treated in the pre-hospital phase. Crude mortality until hospital discharge was the same regardless of pre-hospital mode of transport. After adjustment for initial status, the risk of death was significantly lower (odds ratio (OR): 0.68, 95% confidence interval (CI) 0.47 to 0.98, P = 0.035) for HMICU compared with GMICU. This result did not change after further adjustment for ISS and overall surgical procedures. CONCLUSIONS: This study suggests a beneficial impact of helicopter transport on mortality in severe blunt trauma. Whether this association could be due to better management in the pre-hospital phase needs to be more thoroughly assessed.

Impact of whole-body computed tomography on mortality and surgical management of severe blunt trauma.

INTRODUCTION: The mortality benefit of whole-body computed tomography (CT) in early trauma management remains controversial and poorly understood. The objective of this study was to assess the impact of whole-body CT compared with selective CT on mortality and management of patients with severe blunt trauma. METHODS: The FIRST (French Intensive care Recorded in Severe Trauma) study is a multicenter cohort study on consecutive patients with severe blunt trauma requiring admission to intensive care units from university hospital trauma centers within the first 72 hours. Initial data were combined to construct a propensity score to receive whole-body CT and selective CT used in multivariable logistic regression models, and to calculate the probability of survival according to the Trauma and Injury Severity Score (TRISS) for 1,950 patients. The main endpoint was 30-day mortality. RESULTS: In total, 1,696 patients out of 1,950 (87%) were given whole-body CT. The crude 30-day mortality rates were 16% among whole-body CT patients and 22% among selective CT patients (p = 0.02). A significant reduction in the mortality risk was observed among whole-body CT patients whatever the adjustment method (OR = 0.58, 95% CI: 0.34-0.99 after adjustment for baseline characteristics and post-CT treatment). Compared to the TRISS predicted survival, survival significantly improved for whole-body CT patients but not for selective CT patients. The pattern of early surgical and medical procedures significantly differed between the two groups. CONCLUSIONS: Diagnostic whole-body CT was associated with a significant reduction in 30-day mortality among patients with severe blunt trauma. Its use may be a global indicator of better management.

Diagnostic accuracy of ultrasonography in the acute assessment of common thoracic lesions after trauma.

BACKGROUND: The accuracy of combined clinical examination (CE) and chest radiography (CXR) (CE + CXR) vs thoracic ultrasonography in the acute assessment of pneumothorax, hemothorax, and lung contusion in chest trauma patients is unknown. METHODS: We conducted a prospective, observational cohort study involving 119 adult patients admitted to the ED with thoracic trauma. Each patient, secured onto a vacuum mattress, underwent a subsequent thoracic CT scan after first receiving CE, CXR, and thoracic ultrasonography. The diagnostic performance of each method was also evaluated in a subgroup of 35 patients with hemodynamic and/or respiratory instability. RESULTS: Of the 237 lung fields included in the study, we observed 53 pneumothoraces, 35 hemothoraces, and 147 lung contusions, according to either thoracic CT scan or thoracic decompression if placed before the CT scan. The diagnostic performance of ultrasonography was higher than that of CE + CXR, as shown by their respective areas under the receiver operating characteristic curves (AUC-ROC): mean 0.75 (95% CI, 0.67-0.83) vs 0.62 (0.54-0.70) in pneumothorax cases and 0.73 (0.67-0.80) vs 0.66 (0.61-0.72) for lung contusions, respectively (all P < .05). In addition, the diagnostic performance of ultrasonography to detect pneumothorax was enhanced in the most severely injured patients: 0.86 (0.73-0.98) vs 0.70 (0.61-0.80) with CE + CXR. No difference between modalities was found for hemothorax. CONCLUSIONS: Thoracic ultrasonography as a bedside diagnostic modality is a better diagnostic test than CE and CXR in comparison with CT scanning when evaluating supine chest trauma patients in the emergency setting, particularly for diagnosing pneumothoraces and lung contusions.

Transcranial Doppler to screen on admission patients with mild to moderate traumatic brain injury.

BACKGROUND: Detecting patients at risk for secondary neurological deterioration (SND) after mild to moderate traumatic brain injury is challenging. OBJECTIVE: To assess the diagnostic accuracy of transcranial Doppler (TCD) on admission in screening these patients. METHODS: This prospective, observational cohort study enrolled 98 traumatic brain injury patients with an initial Glasgow Coma Scale score of 9 to 15 whose initial computed tomography (CT) scan showed either absent or mild lesions according to the Trauma Coma Data Bank (TCDB) classification, ie, TCDB I and TCDB II, respectively. TCD measurements of the 2 middle cerebral arteries were obtained on admission under stable conditions in all patients. Neurological outcome was reassessed on day 7. RESULTS: Of the 98 patients, 21 showed SND, ie, a decrease of ≥ 2 points from the initial Glasgow Coma Scale or requiring any treatment for neurological deterioration. Diastolic cerebral blood flow velocities and pulsatility index measurements were different between patients with SND and patients with no SND. Using receiver-operating characteristic analysis, we found the best threshold limits to be 25 cm/s (sensitivity, 92%; specificity, 76%; area under curve, 0.93) for diastolic cerebral blood flow velocity and 1.25 (sensitivity, 90%; specificity, 91%; area under curve, 0.95) for pulsatility index. According to a recursive-partitioning analysis, TCDB classification and TCD measurements were the most discriminative among variables to detect patients at risk for SND. CONCLUSION: In patients with no severe brain lesions on CT after mild to moderate traumatic brain injury, TCD on admission, in complement with brain CT scan, could accurately screen patients at risk for SND.

Medical pre-hospital management reduces mortality in severe blunt trauma: a prospective epidemiological study.

INTRODUCTION: Severe blunt trauma is a leading cause of premature death and handicap. However, the benefit for the patient of pre-hospital management by emergency physicians remains controversial because it may delay admission to hospital. This study aimed to compare the impact of medical pre-hospital management performed by SMUR (Service Mobile d'Urgences et de Réanimation) with non-medical pre-hospital management provided by fire brigades (non-SMUR) on 30-day mortality. METHODS: The FIRST (French Intensive care Recorded in Severe Trauma) study is a multicenter cohort study on consecutive patients with severe blunt trauma requiring admission to university hospital intensive care units within the first 72 hours. Initial clinical status, pre-hospital life-sustaining treatments and Injury Severity Scores (ISS) were recorded. The main endpoint was 30-day mortality. RESULTS: Among 2,703 patients, 2,513 received medical pre-hospital management from SMUR, and 190 received basic pre-hospital management provided by fire brigades. SMUR patients presented a poorer initial clinical status and higher ISS and were admitted to hospital after a longer delay than non-SMUR patients. The crude 30-day mortality rate was comparable for SMUR and non-SMUR patients (17% and 15% respectively; P = 0.61). After adjustment for initial clinical status and ISS, SMUR care significantly reduced the risk of 30-day mortality (odds ratio (OR): 0.55, 95% CI: 0.32 to 0.94, P = 0.03). Further adjustments for the delay to hospital admission only marginally affected these results. CONCLUSIONS: This study suggests that SMUR management is associated with a significant reduction in 30-day mortality. The role of careful medical assessment and intensive pre-hospital life-sustaining treatments needs to be assessed in further studies.

Detecting traumatic internal carotid artery dissection using transcranial Doppler in head-injured patients.

PURPOSE: The early diagnosis of traumatic internal carotid artery dissection (TICAD) is essential for initiating appropriate treatment and improving outcome. We searched for criteria from transcranial Doppler (TCD) measurements on admission that could be associated with subsequent TICAD diagnosis in patients with traumatic brain injury (TBI). METHODS: We conducted a retrospective 1:4 matched (age, mean arterial blood pressure) cohort study of 11 TBI patients with TICAD and absent or mild brain lesions on initial CT scan, 22 TBI controls with comparable brain CT scan lesions (controls 1), and 22 TBI controls with more severe brain CT scan lesions (controls 2) on admission. TCD measurements were obtained on admission from both middle cerebral arteries (MCA). All patients had subsequent CT angiography to diagnose TICAD. RESULTS: A >25% asymmetry in the systolic blood flow velocity between the two MCA was found in 9/11 patients with TICAD versus 0/22 in controls 1 and 5/22 in controls 2 (p < 0.01). The combination of this asymmetry with an ipsilateral pulsatility index < or =0.80 was found in 9/11 patients with TICAD versus none in the two groups of controls (p < 0.01). CONCLUSIONS: Our results suggest that significant asymmetry in the systolic blood flow velocity between the MCAs and a reduced ipsilateral pulsatility index could be criteria from TCD measurements associated with the occurrence of TICAD in head-injured patients. If prospectively validated, these findings could be incorporated in screening protocols for TICAD in patients with TBI.

Equimolar doses of mannitol and hypertonic saline in the treatment of increased intracranial pressure.

OBJECTIVE: To compare the effects of equimolar doses of 20% mannitol solution and of 7.45% hypertonic saline solution (HSS) in the treatment of patients with sustained elevated intracranial pressure (ICP). DESIGN: Parallel, randomized, controlled trial. SETTING: Two intensive care units in a university hospital. PATIENTS: A total of 20 stable patients with a sustained ICP of >20 mm Hg secondary to traumatic brain injury (n = 17) or stroke (n = 3). INTERVENTIONS: A single equimolar infusion (255 mOsm dose) of either 231 mL of 20% mannitol (mannitol group; n = 10 patients) or 100 mL of 7.45% hypertonic saline (HSS group; n = 10 patients) during 20 mins of administration. MEASUREMENTS: ICP, arterial blood pressure, cerebral perfusion pressure, blood flow velocities of middle cerebral artery using continuous transcranial Doppler, brain tissue oxygen tension, serum sodium and osmolality, and urine output during a study period of 120 mins. MAIN RESULTS: The two treatments equally and durably reduced ICP during the experiment. At 60 mins after the start of the infusion, ICP was reduced by 45% +/- 19% of baseline values (mean +/- sd) in the mannitol group vs. 35% +/- 14% of baseline values in the HSS group. Cerebral perfusion pressure and diastolic and mean blood flow velocities were durably increased in the mannitol group, resulting in lower values of pulsatility index at the different times of the experiment (p < .01 vs. HSS). No major changes in brain tissue oxygen tension were found after each treatment. Mannitol caused a significantly greater increase in urine output (p < .05) than HSS, although there was no difference in the vascular filling requirement between the two treatments. HSS caused a significant elevation of serum sodium and chloride at 120 mins after the start of the infusion (p < .01). CONCLUSIONS: A single equimolar infusion of 20% mannitol is as effective as 7.45% HSS in decreasing ICP in patients with brain injury. Mannitol exerts additional effects on brain circulation through a possible improvement in blood rheology. Pretreatment factors, such as serum sodium, systemic hemodynamics, and brain hemodynamics, thus should be considered when choosing between mannitol and HSS for patients with increased ICP.

Duration of adrenal inhibition following a single dose of etomidate in critically ill patients.

OBJECTIVE: To determine the incidence and duration of adrenal inhibition induced by a single dose of etomidate in critically ill patients. DESIGN: Prospective, observational cohort study. SETTING: Three intensive care units in a university hospital. PATIENTS: Forty critically ill patients without sepsis who received a single dose of etomidate for facilitating endotracheal intubation. MEASUREMENTS AND MAIN RESULTS: Serial serum cortisol and 11beta-deoxycortisol samples were taken at baseline and 60 min after corticotropin stimulation test (250 microg 1-24 ACTH) at 12, 24, 48, and 72 h after etomidate administration. Etomidate-related adrenal inhibition was defined by the combination of a rise in cortisol less than 250 nmol/l (9 microg/dl) after ACTH stimulation and an excessive accumulation of serum 11beta-deoxycortisol concentrations at baseline. At 12 h after etomidate administration, 32/40 (80%) patients fulfilled the diagnosis criteria for etomidate-related adrenal insufficiency. This incidence was significantly lower at 48 h (9%) and 72 h (7%). The cortisol to 11beta-deoxycortisol ratio (F/S ratio), reflecting the intensity of the 11beta-hydroxylase enzyme blockade, improved significantly over time. CONCLUSIONS: A single bolus infusion of etomidate resulted in wide adrenal inhibition in critically ill patients. However, this alteration was reversible by 48 h following the drug administration. The empirical use of steroid supplementation for 48 h following a single dose of etomidate in ICU patients without septic shock should thus be considered. Concomitant serum cortisol and 11beta-deoxycortisol dosages are needed to provide evidence for adrenal insufficiency induced by etomidate in critically ill patients.

Emergency endovascular stent graft repair for acute blunt thoracic aortic injury: a retrospective case control study.

OBJECTIVE: To compare surgical and endovascular stent graft (ESG) treatment of blunt thoracic aortic injury (BAI) in the emergency setting. DESIGN AND SETTING: Retrospective case control study in two surgical intensive care units of a university hospital. PATIENTS: 30 patients who presented with BAI between 1995 and 2005: 17 treated surgically and 13 by ESG. The two groups were comparable for the severity of trauma and mean delay before treatment; the mean age was higher in the ESG group (46+/-18 vs. 35+/-15 years). RESULTS: In the surgical group time spent in the operating theater was longer (310+/-130 vs. 140+/-48 min) and blood losses higher (2000+/-1300 vs. no significant bleeding); aortic clamping time was 48+/-20 min. The mortality rate was 15% with ESG (n=2) and 23% with surgery (n=4). Complications of the procedure were more frequent in the surgical group (1 vs. 7). In the ESG group there was one pulmonary embolism. In the surgical group there were three neurological complications, one acute aortic dissection, one perioperative rupture, one periprosthetic leak, and one septic shock. Two complications (postoperative aortic dissection and paraplegia) appeared in the same patient in the surgical group. Intensive care unit length of stay, duration of mechanical ventilation, and catecholamine support were similar in the two groups. CONCLUSIONS: Stent graft for emergency treatment of BAI is efficient and is associated with fewer complications than surgical treatment.

Transcranial Doppler to detect on admission patients at risk for neurological deterioration following mild and moderate brain trauma.

OBJECTIVE: To investigate the contribution of transcranial Doppler measurements obtained in the emergency room for detecting patients with secondary neurological deterioration after mild or moderate brain trauma. DESIGN AND SETTING: Prospective cohort study in the emergency room in a university teaching hospital. PATIENTS: Seventy-eight adult patients admitted to the emergency room after a traumatic brain injury (TBI), including 42 patients with Glasgow Coma Score 14-15 and 36 with 9-13. MEASUREMENTS AND RESULTS: All patients had transcranial Doppler measurements on both middle cerebral arteries and computed tomography on admission. Neurological outcome was assessed 7 days after trauma. Of the patients included 7 and 10 had secondary neurological deterioration after mild and moderate TBI, respectively. On admission these groups of patients had significantly more injuries on computed tomography using the Trauma Coma Data Bank classification and higher pulsatility index using transcranial Doppler than the patients having no subsequent neurological worsening. CONCLUSIONS: Increased pulsatility index after mild or moderate TBI is a reason for concern about the possibility of further neurological deterioration. Computed tomography and Doppler measurements could be combined to detect on admission patients at risk for secondary neurological deterioration in order to improve their initial disposition.