Reperfusion Interval as a Prevention of Lung Injury Due to Limb Ischemia-Reperfusion After Application of Tourniquet in Murine Experimental Study

Indian J Orthop. 2020 Apr 7;54(5):704-710. doi: 10.1007/s43465-020-00100-y. eCollection 2020 Sep.

Abstract

Background: Tourniquet use is prevalent in the orthopaedic field to achieve a bloodless operating field, but it poses risks of local and systemic complications, including lung injury. This study aims to examine the effect of tourniquet application on the hindlimb of a rat to its lung.

Materials and methods: This is an experimental study with 48 male Wistar strain rats as samples. The rats were divided into group A (n = 24), killed directly after fracturization and tourniquet application, and group B (n = 24), killed 14 days post-procedure. Each group was divided into four: group A1/B1 (control group, three hours tourniquet application without reperfusion interval), A2/B2 (5-min reperfusion between 2-h and 1-h tourniquet application), A3/B3 (10-min reperfusion), and A4/B4 (15-min reperfusion). The lung tissue was examined histologically within ten high-power fields (400 × magnification). The severity of lung injury was measured using the Lung Injury Score (LIS). The oxidative damage was measured by determining the malondialdehyde (MDA) level, using the TBARS (thiobarbituric acid reactive substance assay) method.

Results: There was a dose-dependent decrease of LIS and MDA in groups A and B with increasing reperfusion interval. Fifteen-minute reperfusion interval caused a 54.55% and 45.33% LIS reduction in groups A and B, respectively. All pair-wise group comparisons (p < 0.05) showed significant differences. Five-minute interval reduced the MDA level by 16.56% and 30.13% in groups A and B, respectively. All possible pair-wise comparisons in both groups A and B also showed a significant difference (p < 0.05).

Conclusions: Reperfusion interval is a possible clinical approach to mitigate the remote organ damage induced by limb ischemia-reperfusion injury.

Keywords: Lung injury; Reperfusion injury; Tourniquets.