Mortality from isolated civilian penetrating extremity injury.

BACKGROUND: Although studies have ascertained that ten percent of soldiers killed in battle bleed to death from extremity wounds, little data exists on exsanguination and mortality from extremity injuries in civilian trauma. This study examined the treatment course and outcomes of civilian patients who appear to have exsanguinated from isolated penetrating extremity injuries. METHODS: Five and 1/2 years' data (Aug 1994 to Dec 1999) were reviewed from two Level I trauma centers that receive 95% of trauma patients in metropolitan Houston, TX. Records (hospital trauma registries, emergency medical system (EMS) and medical examiner data) were reviewed on all patients with isolated extremity injuries who arrived dead at the trauma center or underwent cardiopulmonary resuscitation (CPR) or emergency center thoracotomy (ECT). RESULTS: Fourteen patients meeting inclusion criteria were identified from over 75,000 trauma emergency center (EC) visits. Average age was 31 years and 93% were males. Gunshot wounds accounted for 50% of the injuries. The exsanguinating wound was in the lower extremity in 10/14 (71%) patients and proximal to the elbow or knee in 12/14 (86%). Ten (71%) had both a major artery and vein injured; one had only a venous injury. Prehospital hemorrhage control was primarily by gauze dressings. Twelve (86%) had "signs of life" in the field, but none had a discernable blood pressure or pulse upon arrival at the EC. Prehospital intravenous access was not obtained in 10 patients (71%). Nine patients underwent ECT, and nine were initially resuscitated (eight with ECT and one with CPR). Those undergoing operative repair received an average of 26 +/- 14 units of packed red blood cells. All patients died, 93% succumbing within 12 hours. CONCLUSION: Although rare, death from isolated extremity injuries does occur in the civilian population. The majority of injuries that lead to immediate death are proximal injuries of the lower extremities. The cause of death in this series appears to have been exsanguination, although definitive etiology cannot be discerned. Intravenous access was not obtainable in the majority of patients. Eight patients (57%) had bleeding from a site that anatomically might have been amenable to tourniquet control. Patients presenting to the EC without any detectable blood pressure and who received either CPR or EC thoracotomy all died.

Cost-effectiveness analysis of nocturnal oximetry as a method of screening for sleep apnea-hypopnea syndrome.

STUDY OBJECTIVE: Determine the utility of nocturnal oximetry as a screening tool for sleep apnea-hypopnea syndrome (SAHS) compared with polysomnography (PSG). DESIGN: Cost-effectiveness analysis based on retrospective review of overnight sleep studies. SETTING: United States Air Force tertiary teaching hospital. PATIENTS: One hundred consecutive patients evaluated for SAHS by overnight sleep study. INTERVENTION: Participants underwent PSG and oximetry on the same night. Patients with obstructive sleep apnea had a continuous positive airway pressure trial. MEASUREMENTS: Oximetry was abnormal when > or =10 events per hour occurred. Two criteria were evaluated. A "deep" pattern of > 4% change in oxyhemoglobin saturation to < or =90%, and a "fluctuating" pattern of repetitive short-duration fluctuations in saturation. The diagnostic accuracy of both methods was compared with PSG. Cost-effectiveness of screening oximetry was compared with PSG alone and use of split-night studies. RESULTS: The fluctuating pattern had a greater sensitivity and negative predictive value, while the deep pattern had a greater specificity and positive predictive value. Oximetry screening using the fluctuating pattern was not as sensitive as PSG for detecting patients with mild disease; 17 of 28 patients (61%) with normal oximetry results had treatable conditions detected by PSG. Cost analysis showed that screening oximetry would save $4,290/100 patients but with considerable loss of diagnostic accuracy. CONCLUSION: Screening oximetry is not cost-effective because of poor diagnostic accuracy despite increased sensitivity using the fluctuating pattern. Greater savings, without loss of diagnostic accuracy, may be achieved through increased utilization of split-night PSGs.