Abstract
Current methodology described to mimic lower limb ischaemia–reperfusion injury (LL-IRI) does not accurately define the procedures and pressures exerted to induce and maintain ischaemia. In this piece of work, we propose a well-defined and detailed rat model that simulates the conditions established in clinical practice guidelines for tourniquet application and allows us to test treatments that aim to prevent/reduce LL-IRI. Eighty-six male WAG/RijHsd rats were subjected to hind limb IRI (LL-IRI), using a mechanical system applying a 1 kg tension to induce and maintain ischemia for 2 or 3 h, and assessed the damage caused by reperfusion at biochemical and muscular levels at different time points. At the biochemical level, both 2 and 3 h of ischemia induced changes (except for electrolyte levels); 3 h of ischemia induced greater changes in specific markers of muscular damage: creatine kinase (CK) and lactate dehydrogenase (LDH). At the histopathological level, 3 h of ischemia and 24 h of reperfusion was associated with an increase in hind limb girth, cross-sectional area, and weight and presence of neutrophils, as well as histological damage in more than 60% of muscle fibres. Our model allows to reliably reproduce the damage associated with the use of a pneumatic tourniquet. CK and LDH, as well as measures of tissue damage, allow to define and characterize the response to LL-IRI-related damage. A period of 3 h of ischemia followed by 3 h of reperfusion caused only local damage but showed greater sensitivity to detect differences in future studies on prophylactic treatments against LL-IRI.
Highlights
Current methodology described to mimic lower limb ischaemia–reperfusion injury (LL-ischemia/ reperfusion injury (IRI)) does not accurately define the procedures and pressures exerted to induce and maintain ischaemia
Only those models described by B onheur[18] and Drysch[19] apply a model that is similar to that used in clinical practice, which uses the minimal limb occlusion pressure (MLOP), defined as the pressure in the tourniquet at which the distal arterial blood flow, as assessed by a Doppler probe held over a distal artery, is occluded
To quantify the lower limb ischaemia–reperfusion injury (LL-IRI), we have chosen those biochemical and histopathological parameters most related to the clinical use, among the many described in the scientific literature, and we have studied the best time of reperfusion to assess them
Summary
Current methodology described to mimic lower limb ischaemia–reperfusion injury (LL-IRI) does not accurately define the procedures and pressures exerted to induce and maintain ischaemia. Literature on techniques for inducing LL-IRI includes invasive surgical procedures, involving muscle disinsertion and surgical excision or clamping of the femoral v essels[9,10], to tourniquet models based on the application of a non-loosening nylon cable tie[11], or rubber or latex b ands[12,13,14,15,16,17,18,19], used either in rats or mice Both elastic tourniquets and high pressure levels applied with a uncontrolled tension tourniquet, such as rubber ring, increase both the frequency and severity of tourniquet-induced local injuries[20,21]. Only those models described by B onheur[18] and Drysch[19] apply a model that is similar to that used in clinical practice, which uses the minimal limb occlusion pressure (MLOP), defined as the pressure in the tourniquet at which the distal arterial blood flow, as assessed by a Doppler probe held over a distal artery, is occluded
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
