Mild-Tourniquet Induced Ischaemia-reperfusion Injury Results in Changes to Haematological, Haemostatic and Inflammatory Parameters

Abstract

Background: Ischaemia-reperfusion injury (IRI) is an underlying condition in cardiovascular disease such as arthrosclerosis and stroke, and occurs during surgery that involves the application of a tourniquet. These clinical conditions are extremely prominent in the United Kingdom. This pilot-study aimed to determine the effects of mild tourniquet induced IRI on specific haematological, haemostatic and inflammatory parameters. Patients and Methods: An In vivo model of mild tourniquet induced IRI was performed on 15 volunteers (n=15). Tourniquet pressure was set between 20-40 mmHg for 10 minutes and rendered the arm temporarily ischaemic. Baseline venous blood samples were taken prior to ischaemia, then following the release of the tourniquet at 7 minutes and 48 hours reperfusion. The parameters investigated included: full blood count, von Willebrand factor (vWF), sE-selectin, prothrombin time (PT), Interleukin-6 (IL-6), IL-8 and IL-10. Results: The results demonstrated a significant increase in vWF following reperfusion (p=0.005), and increasing trends of IL-6, IL-8 and sE-selectin concentrations (p=>0.05). Decreasing PT, white blood cell and platelet counts were observed following IRI but were not significant (p=>0.05). Discussion and Conclusion: The study demonstrated that brief periods of IRI caused changes to haematological, haemostatic and inflammatory parameters. Specifically, a significant increase in vWF concentration was observed following tourniquet induced IRI. This suggests that changes to vascular integrity and that of endothelial activation may be occurring. The results of this pilot-study provide a basis for further exploration of haematological, haemostatic and inflammatory parameters following IRI, which may increase our knowledge and understanding of a subject area that is not fully understood. Ultimately, further studies may highlight areas of therapeutic intervention for the underlying occurrence of IRI in pathological conditions, such as cardiovascular disease (CVD) and surgeries that involve the application of a tourniquet. These predictors, however, need further work to validate reliability in a clinical setting.