A Pre-clinical Rat Model for the Study of Ischemia-reperfusion Injury in Reconstructive Microsurgery

Abstract

Ischemia-reperfusion injury is the main cause of flap failure in reconstructive microsurgery. The rat is the preferred preclinical animal model in many areas of biomedical research due to its cost-effectiveness and its translation to humans. This protocol describes a method to create a preclinical free skin flap model in rats with ischemia-reperfusion injury. The described 3 cm x 6 cm rat free skin flap model is easily obtained after the placement of several vascular ligatures and the section of the vascular pedicle. Then, 8 h after the ischemic insult and completion of the microsurgical anastomosis, the free skin flap develops the tissue damage. These ischemia-reperfusion injury-related damages can be studied in this model, making it a suitable model for evaluating therapeutic agents to address this pathophysiological process. Furthermore, two main monitoring techniques are described in the protocol for the assessment of this animal model: transit-time ultrasound technology and laser speckle contrast analysis.

Evaluation of Predictive Values of an Automatic Device Measuring Oximetry in Free Flaps

“…Since we performed the clamping, we took this event as the gold standard. The model was implemented following the technique described by Ballestin et al, 17 with a cutaneous flap based on the inferior epigastric vessels.…”

“…In this model, we did not dissect the pedicles adventitia to avoid spasm or perfusion bias. 17 However, we did skeletonize the pedicle to identify it and to ensure pedicle occlusion with the clamp. The flap was placed in a rigid nylon mesh with squares of 5 × 7 cm to avoid curling, and was secured to that mesh using nylon simple sutures.…”

“…The sensitivity, specificity, negative predictive value, and positive predictive value were calculated. 17…”