Ultrasound at the Role 1: An Analysis of After-Action Reviews from the Prehospital Trauma Registry.

BACKGROUND: Ultrasound is a portable and adaptable imaging modality used widely in the care of trauma patients. The initial exam, known as the "Focused Assessment in Trauma (FAST) exam focused on the evaluation for hemoperitoneum and hemopericardium. In recent years, the exam has expanded to include evaluate for thoracic pathology, including pneumothorax, and is now known as the "Extended Focused Assessment in Trauma" (E-FAST) exam. METHODS: We reviewed after-action reviews (AAR) from the Joint Trauma System Prehospital Trauma Registry from 2013-2014 in which the use of an ultrasound exam was noted. Given the largely unstructured nature of the AARs, we selected relevant information from the free text available. RESULTS: Our initial dataset contained 705 casualties, of which we identified 45 cases containing the key words with AAR data for review: 39 cases involved the use of the FAST exam, three explicitly described the use of pulmonary ultrasound and they were categorized as E-FAST exams, two cases described the use of point of care echo to evaluate for cardiac standstill, and two cases described the use of ultrasound to evaluate for vascular injury. Of those with vital signs documented, 25% (11) reported at least one episode of tachycardia (≥120/min) and 16% (7) with at least one episode of systolic hypotension (less than 90mmHg). Of the 45 cases reviewed, six were recorded as equivocal, which we interpreted to indicate more training in either performance or interpretation of the exam was needed. CONCLUSIONS: Our findings suggest that training in both the FAST exam and E-FAST has the potential to improve patient care for military trauma patients. A performance improvement system would enable real-time confirmation of findings and feedback for training and quality improvement.

Role of heat shock protein 90 and endothelial nitric oxide synthase during early anesthetic and ischemic preconditioning.

BACKGROUND: Nitric oxide is known to be essential for early anesthetic preconditioning (APC) and ischemic preconditioning (IPC) of myocardium. Heat shock protein 90 (Hsp90) regulates endothelial nitric oxide synthase (eNOS) activity. In this study, the authors tested the hypothesis that Hsp90-eNOS interactions modulate APC and IPC. METHODS: Myocardial infarct size was measured in rabbits after coronary occlusion and reperfusion in the absence or presence of preconditioning within 30 min of isoflurane (APC) or 5 min of coronary artery occlusion (IPC), and with or without pretreatment with geldanamycin or radicicol, two chemically distinct Hsp90 inhibitors, or N-nitro-L-arginine methyl ester, a nonspecific nitric oxide synthase NOS inhibitor. Isoflurane-dependent nitric oxide production was measured (ozone chemiluminescence) in human coronary artery endothelial cells or mouse cardiomyocytes, in the absence or presence of Hsp90 inhibitors or N-nitro-L-arginine methyl ester. Interactions between Hsp90 and eNOS, and eNOS activation, were assessed with immunoprecipitation, immunoblotting, and confocal microscopy. RESULTS: APC and IPC decreased infarct size (by 50% and 59%, respectively), and this action was abolished by Hsp90 inhibitors. N-nitro-L-arginine methyl ester blocked APC but not IPC. Isoflurane increased nitric oxide production in human coronary artery endothelial cells concomitantly with an increase in Hsp90-eNOS interaction (immunoprecipitation, immunoblotting, and immunohistochemistry). Pretreatment with Hsp90 inhibitors abolished isoflurane-dependent nitric oxide production and decreased Hsp90-eNOS interactions. Isoflurane did not increase nitric oxide production in mouse cardiomyocytes, and eNOS was below the level of detection. CONCLUSION: The results indicate that Hsp90 plays a critical role in mediating APC and IPC through protein-protein interactions, and suggest that endothelial cells are important contributors to nitric oxide-mediated signaling during APC.