Prehospital ABC Score Accurately Forecasts Patients Who Will Require Immediate Resource Utilization.

OBJECTIVES: Scoring systems, such as the Assessment of Blood Consumption (ABC) Score, are used to identify patients at risk for massive transfusion (MT, ≥10 U red blood cells in 24 hours). Our aeromedical transport helicopter uses ultrasound to perform the Focused Assessment with Sonography for Trauma (FAST) examination. Our objective was to evaluate the ability of the Prehospital ABC (PhABC) Score to predict blood transfusions and the need for emergent laparotomy. METHODS: Post hoc analysis of a prospective observational study of trauma patients who underwent an in-flight FAST during aeromedical transport during a 7-month period. PhABC Score was positive if ≥2 of the following were present in flight: penetrating trauma, heart rate >120 bpm, systolic blood pressure <90 mm Hg, or a positive abdominal FAST. The PhABC Score was evaluated by area under the receiver operating characteristic (AUROC) curves and logistic regression. RESULTS: A total of 291 trauma patients met inclusion criteria, 23 underwent emergent laparotomy, and 12 received an MT. A positive PhABC Score predicted emergent laparotomy, with a positive predictive value of 48% and a negative predictive value of 95% (sensitivity 46%, specificity 96%, AUROC curve 0.83). A positive PhABC Score also predicted receipt of an MT with a positive predictive value of 28% and a negative predictive value of 94% (sensitivity 33%, specificity 93%, AUROC curve 0.77). Multiple logistic regression identified FAST as the most powerful contributor of the PhABC Score to the prediction of both emergent laparotomy (odds ratio 8.5, P < 0.001) and MT (odds ratio 5.9, P < 0.001). CONCLUSIONS: The PhABC Score effectively predicts in-hospital resource utilization. It provides an outstanding undertriage rate from the prehospital setting, and it is helpful to improve trauma team activation, mobilize blood products, and prepare the operating room.

Prospective evaluation of prehospital trauma ultrasound during aeromedical transport.

BACKGROUND: Ultrasound is widely considered the initial diagnostic imaging modality for trauma. Preliminary studies have explored the use of trauma ultrasound in the prehospital setting, but the accuracy and potential utility is not well understood. OBJECTIVE: We sought to determine the accuracy of trauma ultrasound performed by helicopter emergency medical service (HEMS) providers. METHODS: Trauma ultrasound was performed in flight on adult patients during a 7-month period. Accuracy of the abdominal, cardiac, and lung components was determined by comparison to the presence of injury, primarily determined by computed tomography, and to required interventions. RESULTS: HEMS providers performed ultrasound on 293 patients during a 7-month period, completing 211 full extended Focused Assessment with Sonography for Trauma (EFAST) studies. HEMS providers interpreted 11% of studies as indeterminate. Sensitivity and specificity for hemoperitoneum was 46% (95% confidence interval [CI] 27.1%-94.1%) and 94.1% (95% CI 89.2%-97%), and for laparotomy 64.7% (95% CI 38.6%-84.7%) and 94% (95% CI 89.2%-96.8%), respectively. Sensitivity and specificity for pneumothorax were 18.7% (95% CI 8.9%-33.9%) and 99.5% (95% CI 98.2%-99.9%), and for thoracostomy were 50% (95% CI 22.3%-58.7%) and 99.8% (98.6%-100%), respectively. The positive likelihood ratio for laparotomy was 10.7 (95% CI 5.5-21) and for thoracostomy 235 (95% CI 31-1758), and the negative likelihood ratios were 0.4 (95% CI 0.2-0.7) and 0.5 (95% CI 0.3-0.8), respectively. Of 240 cardiac studies, there was one false-positive and three false-negative interpretations (none requiring intervention). CONCLUSIONS: HEMS providers performed EFAST with moderate accuracy. Specificity was high and positive interpretations raised the probability of injury requiring intervention. Negative interpretations were predictive, but sensitivity was not sufficient for ruling out injury.

Ultrasonography versus computed tomography for suspected nephrolithiasis.

BACKGROUND: There is a lack of consensus about whether the initial imaging method for patients with suspected nephrolithiasis should be computed tomography (CT) or ultrasonography. METHODS: In this multicenter, pragmatic, comparative effectiveness trial, we randomly assigned patients 18 to 76 years of age who presented to the emergency department with suspected nephrolithiasis to undergo initial diagnostic ultrasonography performed by an emergency physician (point-of-care ultrasonography), ultrasonography performed by a radiologist (radiology ultrasonography), or abdominal CT. Subsequent management, including additional imaging, was at the discretion of the physician. We compared the three groups with respect to the 30-day incidence of high-risk diagnoses with complications that could be related to missed or delayed diagnosis and the 6-month cumulative radiation exposure. Secondary outcomes were serious adverse events, related serious adverse events (deemed attributable to study participation), pain (assessed on an 11-point visual-analogue scale, with higher scores indicating more severe pain), return emergency department visits, hospitalizations, and diagnostic accuracy. RESULTS: A total of 2759 patients underwent randomization: 908 to point-of-care ultrasonography, 893 to radiology ultrasonography, and 958 to CT. The incidence of high-risk diagnoses with complications in the first 30 days was low (0.4%) and did not vary according to imaging method. The mean 6-month cumulative radiation exposure was significantly lower in the ultrasonography groups than in the CT group (P<0.001). Serious adverse events occurred in 12.4% of the patients assigned to point-of-care ultrasonography, 10.8% of those assigned to radiology ultrasonography, and 11.2% of those assigned to CT (P=0.50). Related adverse events were infrequent (incidence, 0.4%) and similar across groups. By 7 days, the average pain score was 2.0 in each group (P=0.84). Return emergency department visits, hospitalizations, and diagnostic accuracy did not differ significantly among the groups. CONCLUSIONS: Initial ultrasonography was associated with lower cumulative radiation exposure than initial CT, without significant differences in high-risk diagnoses with complications, serious adverse events, pain scores, return emergency department visits, or hospitalizations. (Funded by the Agency for Healthcare Research and Quality.).

Evaluation of a training curriculum for prehospital trauma ultrasound.

BACKGROUND: In the United States, ultrasound has rarely been incorporated into prehospital care, and scant descriptions of the processes used to train prehospital providers are available. OBJECTIVES: Our objective was to evaluate the effectiveness of an extended focused assessment with sonography for trauma (EFAST) training curriculum that incorporated multiple educational modalities. We also aimed to determine if certain demographic factors predicted successful completion. METHODS: All aeromedical prehospital providers (APPs) for a Level I trauma center took a 25-question computer-based test to ascertain baseline knowledge. Questions were categorized by content and format. Training over a 2-month period included a didactic course, a hands-on training session, proctored scanning sessions in the Emergency Department, six Internet-based training modules, pocket flashcards, a review session, and remedial training. At the conclusion of the training curriculum, the same test and an objective structured clinical examination were administered to evaluate knowledge gained. RESULTS: Thirty-three of 34 APPs completed training. The overall pre-test and post-test means and all content and format subsets showed significant improvement (p < 0.0001 for all). No APP passed the pre-test, and 28 of 33 passed the post-test with a mean score of 78%. No demographic variable predicted passing the post-test. Twenty-seven of 33 APPs passed the objective structured clinical examination, and the only predictive variable was passing the post-test (odds ratio 1.21, 95% confidence interval 1.00-1.25, p = 0.045). CONCLUSION: The implementation of a multifaceted EFAST prehospital training program is feasible. Significant improvement in overall and subset testing scores suggests that the test instrument was internally consistent and sufficiently sensitive to capture knowledge gained as a result of the training. Demographic variables were not predictive of test success.

Utility of the cardiac component of FAST in blunt trauma.

BACKGROUND: Focused assessment with sonography in trauma (FAST) is widely used and endorsed by guidelines, but little evidence exists regarding the utility of the cardiac portion in blunt trauma. The traditional FAST includes the routine performance of cardiac sonography, regardless of risk for hemopericardium. STUDY OBJECTIVES: Our goal was to estimate the prevalence of hemopericardium due to blunt trauma and determine the sensitivity of certain variables for the presence of blunt hemopericardium. METHODS: We performed a retrospective chart review of two institutional databases at a large urban Level I trauma center to determine the prevalence of blunt hemopericardium and cardiac rupture and incidental or insignificant effusions. We evaluated the sensitivity of major mechanism of injury, hypotension, and emergent intubation for blunt hemopericardium and cardiac rupture. RESULTS: Eighteen patients had hemopericardium and cardiac rupture (14 and 4, respectively) out of 29,236 blunt trauma patients in the Trauma Registry over an 8.5-year period. The prevalence was 0.06% (95% confidence interval [CI] 0.04-0.09%). The prevalence of incidental or insignificant effusions was 0.13% (95% CI 0.09-0.18%). One case of blunt hemopericardium was identified in the emergency ultrasound database out of 777 cardiac ultrasounds over a 3-year period. No patient with blunt hemopericardium or cardiac rupture presented without a major mechanism of injury, hypotension, or emergent intubation. CONCLUSION: Blunt hemopericardium is rare. High-acuity variables may help guide the selective use of echocardiography in blunt trauma.

Heterotopic pregnancy diagnosed by emergency ultrasound.

We present a case of heterotopic pregnancy rapidly diagnosed by an emergency physician. To the best of our knowledge, this is the first report of an emergency physician using bedside ultrasound to diagnose an ectopic pregnancy present simultaneously with an intrauterine pregnancy. Other unique features of this case include the diagnosis being made on initial evaluation and the patient's lack of risk factors for heterotopic pregnancy. A review of the cases of heterotopic pregnancy reported in the emergency medicine literature, the rising prevalence of the disease, and factors that may facilitate in making the diagnosis are discussed as well.