Is portable ultrasonography accurate in the evaluation of Schanz pin placement during extremity fracture fixation in austere environments?

OBJECTIVE: The purpose of this study was to investigate the efficacy of ultrasonography to confirm Schanz pin placement in a cadaveric model, and the interobserver repeatability of the ultrasound methodology. DESIGN: This investigation is a repeated measures cadaveric study with multiple examiners. PARTICIPANTS: Cadaveric preparation and observations were done by an orthopaedic traumatologist and resident, and two general surgery traumatologists. INTERVENTIONS: A total of 16 Schanz pins were equally placed in bilateral femora and tibiae. Four examiners took measurements of pin protrusion beyond the distal cortices using first ultrasonography and then by direct measurement after gross dissection. MAIN OUTCOME MEASURE(S): Distal Schanz pin protrusion length measurements from both ultrasonography and direct measurement post dissection. RESULTS: Schanz pin protrusion measurements are underestimated by ultrasonography (p < 0.01) by an average of 10 percent over the range of 5 to 18 mm, and they display a proportional bias that increases the under reporting as the magnitude of pin protrusion increases. Ultrasound data demonstrate good linear correlation and closely represent actual protrusion values in the 5 to 12 mm range. Interobserver repeatability analysis demonstrated that all examiners were not statistically different in their measurements despite minimal familiarity with the ultrasound methodology (p > 0.8). CONCLUSIONS: Despite the statistical imparity of pin protrusion measurement via ultrasound compared to that of gross dissection, a consideration of the clinical relevance of ultrasound measurement bias during an austere operating theatre leads to the conclusion that ultrasonography is an adequate methodology for Schanz pin protrusion measurement.

Pulmonary contusions and critical care management in thoracic trauma.

Many victims of thoracic trauma require ICU care and mechanical ventilatory support. Pressure and volume-limited modes assist in the prevention of ventilator-associated lung injury. Ventilator-associated pneumonia is a significant cause of posttraumatic morbidity and mortality. Minimizing ventilator days, secretion control, early nutritional support, and patient positioning are methods to reduce the risk of pneumonia.

Complete occlusion after blunt injury to the abdominal aorta.

BACKGROUND: Injury to the abdominal aorta after blunt trauma is uncommon. When this injury results in complete vessel occlusion, the presentation is dramatic. Timely intervention is essential. METHODS: After a case report, we examined all reported cases of complete occlusion after blunt injury to the abdominal aorta and reviewed the cause, presentation, and management of this injury. RESULTS: Complete vessel occlusion arises from intimal injury. The most frequent mechanism is compression from a seat belt or steering wheel during a motor vehicle crash. Patients present with absent femoral and distal pulses in association with lower extremity neuropathy. Intervention commonly involves bypass grafting of the abdominal aorta. CONCLUSION: Complete occlusion after blunt trauma to the abdominal aorta is rare. Neurologic deficits most commonly arise from peripheral nerve ischemia. Reperfusion within 6 hours confers a greater chance of limb salvage and neurologic recovery.

A new method of continuous venovenous rewarming.

PURPOSE: Hypothermia is a significant problem in medicine and is part of a deadly triad, including hypothermia, acidosis, and coagulopathy. Multiple methods of rewarming are used to treat moderate hypothermia. The purpose of this study was to compare the effectiveness of continuous venovenous rewarming (CVVR) using the FMS 2000 (Belmont Instrument Corp., Billerica, Massachusetts) in conjunction with external rewarming techniques versus external rewarming alone in the porcine model. METHODS: Ten subject animals, each weighing approximately 40 kg, were evenly divided and randomly assigned to either a control group using external rewarming techniques alone or the CVVR group utilizing the FMS 2000 in addition to the external rewarming techniques used in the control group. Hypothermia was induced in the swine model using cold water immersion to achieve a core temperature of 30 degrees C. Both esophageal and rectal temperature probes were used to monitor and record core body temperatures every 15 minutes during the experiment. Each study animal was then rewarmed until a core temperature of at least 37 degrees C was recorded in both the esophageal and rectal probes. The animals were observed clinically for 3 days after the study. RESULTS: The average time required to rewarm the control group was 253 minutes, compared with 113 minutes in the CVVR group. After 30 minutes of rewarming, the difference between the 2 groups with respect to core temperature was statistically significant (p = 0.002). A drop in core temperature after the initiation of rewarming, or after-drop, was noted in the control group animals, but not in the CVVR group. This difference was statistically significant after 15 minutes of rewarming (p = 0.015) CONCLUSIONS: Venovenous rewarming utilizing the FMS 2000 fluid management system is more effective than is standard therapy alone for rewarming in the moderately hypothermic porcine model. This finding may prove clinically useful in the treatment of patients suffering from moderate hypothermia.