Impact of Ischemia Duration on Lower Limb Salvage in Combat Casualties

Abstract

Introduction: The 6-hour threshold to revascularization of an ischemic limb is ubiquitous in the trauma literature, however, contemporary evidence suggests that this threshold should be less. This study aims to characterize the relationship between the duration of limb ischemia and successful limb salvage following lower extremity arterial trauma. Methods: This is a cohort study of the United States and UK military service members injured while serving in Iraq or Afghanistan between 2003 and 2013. Consecutive patients who sustained iliac, femoral, or popliteal artery injuries, and underwent surgery to attempt revascularization, were included. The association between limb outcome and the duration of limb ischemia was assessed using the Kaplan-Meier method. Results: One hundred twenty-two patients (129 limbs) who sustained iliac (2.3%), femoral (56.6%), and popliteal (41.1%) arterial injuries were included. Overall, 87 limbs (67.4%) were successfully salvaged. The probability of limb salvage was 86.0% when ischemia was ≤1 hour; 68.3% when between 1 and 3 hours; 56.3% when between 3 and 6 hours; and 6.7% when >6 hours (P<0.0001). Shock more than doubled the risk of failed limb salvage [hazard ratio=2.42 (95% confidence interval: 1.27–4.62)]. Conclusions: Limb salvage is critically dependent on the duration of ischemia with a 10% reduction in the probability of successful limb salvage for every hour delay to revascularization. The presence of shock significantly worsens this relationship. Military trauma systems should prioritize rapid hemorrhage control and early limb revascularization within 1 hour of injury.

Analysis of the Risk Factors for Free Flap Necrosis in Soft Tissue Reconstruction of the Lower Limbs

“…The authors have not found other studies on the relationship between post‐injury shock and free flap necrosis. With the development of damage control surgery and microsurgical techniques, most severely injured limbs can survive emergency reconstruction of blood circulation, and satisfactory results can be obtained by secondary flap coverage 22–24 . The Department of Orthopedic Trauma in our hospital implements a 24‐h emergency duty system and has skilled microsurgical techniques, which are key factors in improving the survival rate of limb salvage and free flaps.…”

Immediate identification and management of an open posterior knee dislocation: Important lessons from a case report

“…Time-to-first intervention plays a critical role in influencing outcomes for knee dislocation. A reduction of 10 % in the probability of successful salvage for every hour of delay in management has been described in military limb trauma patients with vascular injury, and this relationship between time and salvage rates worsens considerably in the presence of shock [ 14 ]. A delay in reperfusion of more than 8 h has demonstrated to increase the risk of amputation by approximately 86 % in comparison to 11 % if the limb is re-perfused within 8 h [ 1 , 15 ].…”

Implicações Clínicas no Uso do Torniquete em Atendimento Pré-hospitalar: Uma Revisão Narrativa de Literatura

“…16 Essa isquemia induzida pela aplicação de torniquete leva à hipóxia tecidual, hipoperfusão e hiponutrição. 18 Geralmente, após esse mecanismo, os metabólitos celulares ficam "aprisionados", promovendo uma acidose metabólica local. Além disso, essas substâncias potencializam a necrose e a apoptose celular, fazendo o recrutamento de células pró-inflamatórias que resultam nas manifestações clínicas sistêmicas do paciente traumático.…”