Probable cause in helicopter emergency medical services crashes: what role does ownership play?

BACKGROUND: The National Transportation Safety Board (NTSB) ranks helicopter emergency medical services (HEMS) as one of the most perilous occupations in the United States, with improvements in its safety of highest priority. As many injured patients are transported by helicopter, this is of particular concern to the trauma community. The use of HEMS is associated with a heightened degree of inherent risk. We hypothesized that this risk is not uniform and varies with the entity providing HEMS, specifically, commercial versus public safety providers. METHODS: The NTSB accident database was queried to identify all HEMS-involved events for the 15-year period 1998 to 2012. The NTSB investigation report was reviewed to obtain crash details including probable cause. These were analyzed on the basis of HEMS ownership. Statistical analyses were performed using analysis of variance and Fisher's exact test as appropriate. RESULTS: During the study period, 139 (6.8%) of 2,040 crashes involved HEMS and occurred across 134 cities in 37 states, killing 120 and seriously injuring 146. Of these, 118 involved commercial, 14 not-for-profit, and 7 public safety HEMS. Analyzed in 5-year blocks, no decrease in crash incidence was seen (p = 0.7, analysis of variance). Human and pilot errors were significantly more common among commercial HEMS compared with public safety HEMS (91 of 118 vs. 2 of 7, p = 0.013, and 75 of 116 vs. 1 of 7, p = 0.017, Fisher's exact test). Conditions for which training was not adequate, limited resources, inadequate equipment, and the undertaking of suboptimal trips were identified as key factors. Trauma patients were involved in 34 transports (24.5%), with a fatal or serious outcome in 68 crew/patients on 12 flights. CONCLUSION: Potentially preventable human and pilot error-related HEMS crashes are significantly more frequent among commercial compared with public safety providers. Deficiencies in training, reduced availability of equipment and resources, as well as questionable flight selection seem to play a key role. LEVEL OF EVIDENCE: Epidemiologic study, level III.

Cystogram follow-up in the management of traumatic bladder disruption.

BACKGROUND: The utility of obtaining a routine cystogram after the repair of intraperitoneal bladder disruption before urethral catheter removal is unknown. This study was designed to examine whether follow-up cystogram evaluation after traumatic bladder disruption affected the clinical management of these injuries. We hypothesized that routine cystograms, after operative repair of intraperitoneal bladder disruptions, provide no clinically useful information and may be eliminated in the management of these injuries. METHODS: Our prospectively collected trauma database was retrospectively reviewed for all ICD-9 867.0 and 867.1 coded bladder injuries over a 6-year period ending in June 2004. Demographics, clinical injury data, detailed operative records, and imaging studies were reviewed for each patient. Bladder injuries were categorized as intraperitoneal (IP) or extraperitoneal (EP) bladder disruptions based on imaging results and operative exploration. Patients with IP injuries were further subdivided into those with "simple" dome disruptions or through-and-through penetrating injuries and "complex" injuries involving the trigone or ureter reimplantation. All patients sustaining isolated ureteric or urethral injury were excluded from further analysis. RESULTS: In all, 20,647 trauma patients were screened for bladder injury. Out of this group, there were 50 IP (47 simple, 3 complex) and 37 EP injuries available for analysis. All IP injuries underwent operative repair. Eight of the IP injuries (all simple) had no postoperative cystogram and all were doing well at 1- to 4-week follow-up. The remaining 42 patients underwent a postoperative cystogram at 15.3 +/- 7.3 days (range 7 to 36 days). All simple IP injuries had a negative postoperative cystogram. The only positive study was in one of the three complex IP injuries. In the EP group, 21.6% had positive cystograms requiring further follow-up and intervention. CONCLUSIONS: Patients sustaining extraperitoneal and complex intraperitoneal bladder disruptions require routine cystogram follow-up. In those patients undergoing repair of a simple intraperitoneal bladder disruption, however, routine follow-up cystograms did not affect clinical management. Further prospective evaluation to determine the optimal timing of catheter removal in this patient population is warranted.

Magnetic resonance cholangiopancreatography accurately detects common bile duct stones in resolving gallstone pancreatitis.

BACKGROUND: There is controversy about the optimal method to detect common bile duct (CBD) stones in patients with mild resolving gallstone pancreatitis. The aim of this study was to evaluate magnetic resonance cholangiopancreatography (MRCP) in detecting choledocholithiasis in this group of patients. STUDY DESIGN: A prospective randomized trial was conducted. Patients randomized to group 1 (n = 34) underwent laparoscopic cholecystectomy (LC) and intraoperative cholangiography (IOC). Those randomized to group 2 (n = 29) had preoperative MRCP, of these, patients with negative MRCP underwent LC and IOC, patients with positive MRCP had preoperative ERCP followed by LC. RESULTS: Sixty-three patients were randomized (34 to group 1 and 29 to group 2). CBD stones were found in 5 patients in group 1. CBD exploration was performed in 2 patients, preoperative ERCP in 1, and postoperative ERCP in the other 2. MRCP showed CBD stones in 4 patients in group 2. There were two false-positive MRCPs. Four patients with a negative MRCP did not have IOC or ERCP, the remaining 21 patients with a negative MRCP had a negative IOC. The MRCP sensitivity was 100% (95% CI, 16-100%), specificity 91% (95% CI, 72-99%), positive predictive value 50% (95% CI, 7-93%), negative predictive value 100% (95% CI, 84-100%), and accuracy 92% (95% CI, 74-99%). CONCLUSIONS: Patients with resolving gallstone pancreatitis and a negative MRCP do not need preoperative ERCP or IOC. Only patients with a positive MRCP will require preoperative ERCP.

Portal vein thrombosis: an unusual complication of laparoscopic cholecystectomy.

BACKGROUND: Complications following laparoscopic cholecystectomy are encountered infrequently due to increasing proficiency in laparoscopic surgery. The occurrence of portal venous thrombosis following laparoscopic cholecystectomy has not been previously described and forms the basis of this report. METHODS: A healthy, 32-year-old, female on oral contraceptives underwent an uneventful laparoscopic cholecystectomy for symptomatic gallbladder disease. Sequential compression devices and mini-dose unfractionated heparin were used before the procedure. The patient was discharged home on the first postoperative day without complaints. She returned 1 week later with nausea, bloating, and diffuse abdominal pain. RESULTS: Ultrasonography of the abdomen revealed thrombosis of the portal vein not seen in the preoperative ultrasound and the superior mesenteric vein. Computer tomography of the abdomen and pelvis on the same day confirmed this finding and showed a wedge-shaped infarction of the right lobe of the liver. The patient was anticoagulated with intravenous heparin. An extensive coagulation workup revealed elevation of the Immunoglobulin G anticardiolipin antibody. A percutaneous transhepatic portal vein thrombectomy was performed. A postprocedure duplex ultrasound of the abdomen demonstrated recannalization of the portal venous system with no flow voids. Anticoagulation therapy was continued, and the patient was discharged home with resolution of her ileus. She was maintained on a therapeutic dose of warfarin. CONCLUSIONS: This case demonstrates an unusual complication of laparoscopic cholecystectomy. It may have resulted from the use of oral contraceptives, elevation of the Immunoglobulin G anticardiolipin antibody, unrecognized trauma, and was accentuated by the pneumoperitoneum generated for the performance of the laparoscopic cholecystectomy. Our case report provides insight and poses questions regarding necessary perioperative measures for thromboprophylaxis in young females on oral contraceptives undergoing elective laparoscopic abdominal surgery.

Surgeon-performed ultrasound in the ICU setting.

Evaluation of critically ill patients is often challenging due to altered sensorium, underlying disease, and the presence of multiple drains or monitoring devices. In such circumstances, the ability of physicians to perform ultrasound examinations in the intensive care unit provides a useful diagnostic and therapeutic adjunct. In this article,we review the application of surgeon-performed ultrasonography in the evaluation and management of critically ill patients.

Blood substitutes.

PURPOSE OF REVIEW: Risk of disease transmission and limitations in the ability to transfuse in the prehospital or combat setting have stimulated research in the field of oxygen therapeutics. Several products have completed safety trials and are presently undergoing investigation for their efficacy. In the near future, the clinician will likely employ these products in the management of a variety of patient populations. Though similar in their oxygen carrying capacity, each agent possesses distinct physiologic effects. Understanding of the benefits and shortcomings of the various compounds is essential in order to optimally utilize them in various clinical settings. This review provides an overview of recent developments in the field of oxygen therapeutics and highlights results of clinical trials. RECENT FINDINGS: Modified hemoglobin solutions of human or bovine origin and perfluorochemical-based emulsions are in advanced stages of clinical testing. Bovine hemoglobin-based solutions have been associated with vascular reactivity, methemoglobin formation and development of antibodies. Larger safety trials are necessary before they can find widespread use. Polymerized human hemoglobin solutions have a favorable safety profile in early trials and have been effective as a resuscitation fluid in circumstances when red cells may be unavailable. Unfortunately, outdated human blood, the substrate for this product, is itself in short supply. Perfluorocarbons similarly reduce the need for allogeneic transfusion, but the need for high-inspired oxygen levels currently limits use. Recombinant, polymer-encapsulated and additional forms of chemically modified hemoglobins are being developed and are undergoing testing in animal models SUMMARY: Oxygen carriers offer a viable alternative to allogeneic transfusion. All oxygen therapeutic agents are not clinically equivalent. Optimal utilization requires a thorough understanding of the therapeutic potentials and adverse effects of the solution being considered for use.