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Objective Prehospital limb amputation is a rare but potentially life-saving intervention. When patients cannot be extricated due to limb entrapment or have hemodynamic compromise that precludes a prolonged extrication, they may benefit from an emergent prehospital amputation. The objective was to experimentally compare three prehospital amputation techniques on porcine legs. Methods The three techniques studied were a scalpel with a Gigli saw, a hacksaw, and a reciprocating saw. For the first technique, a scalpel was used to make a circumferential incision in the soft tissue and a Gigli wire saw to cut through the bone. The second and third techniques only used a saw and did not require soft tissue incision with a scalpel. Three providers including an emergency medicine physician, a paramedic, and a medical student performed three amputations of each technique, resulting in twenty-seven total amputations. The primary outcome was amputation time. Secondary outcomes were rate of instrument malfunction and cleanliness of cut. Results The primary outcome of amputation time was different between techniques. The Gigli saw technique took 32.86 ± 16.53 s (mean ± SD), hacksaw technique 6.28 ± 0.76 s, and reciprocating saw technique 2.84 ± 0.40 s. There were no differences in amputation time between participants for a given amputation technique. The Gigli saw technique had an instrument malfunction on 3/9 trials which was distinct from the other techniques. Differences in cleanliness of cut were nonsignificant. Conclusions Prehospital limb amputation with a hacksaw or reciprocating saw may result in faster completion of the time-sensitive procedure with fewer instrument malfunctions.

In the pregnant mouse, the hormone leptin is primarily produced by adipose tissue and does not significantly cross the placenta into fetal circulation. Nonetheless, leptin treatment during gestation affects offspring phenotypes. Leptin treatment also affects placental trophoblast cells in vitro, by altering proliferation, invasion and nutrient transport. The goal of the present study was to determine whether the absence of placental leptin receptors alters placental development and gene expression. Leprdb−3j+ mice possessing only one functional copy of the leptin receptor were mated to obtain wildtype, Leprdb−3j+ and Leprdb−3j/db−3j conceptuses, which were then transferred to wildtype recipient dams. Placentas were collected at gestational d18.5 to examine placental morphology and gene expression. Placentas lacking functional leptin receptor had reduced weights, but were otherwise morphologically indistinguishable from control placentas. Relative mRNA levels, however, were altered in Leprdb−3j/db−3j placentas, particularly transcripts related to amino acid and lipid metabolism and transport. Consistent with a previous in vitro study, leptin was found to promote expression of stathmin, a positive regulator of trophoblast invasion, and of serotonin receptors, potential mediators of offspring neurological development. Overall placental leptin receptor was found not to play a significant role in morphological development of the placenta, but to regulate placental gene expression, including in metabolic pathways that affect fetal growth.