Brief ex vivo perfusion with heparinized and/or citrated whole blood enhances tolerance of free muscle flaps to prolonged ischemia

• Published in: Microsurgery Vol. 19; no. 3; pp. 135 - 140
• Main Authors: Fowler, J. David, Li, Xiaolu, Cooley, Brian C.
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Inc 1999; Wiley-Liss
• Subjects: Analysis of Variance; Animals; Anticoagulants - therapeutic use; Biological and medical sciences; Biopsy; Blood; Citrates - therapeutic use; Edema - physiopathology; Femoral Artery - surgery; Femoral Vein - surgery; Heparin - therapeutic use; Indicators and Reagents; Ischemia - physiopathology; Male; Medical sciences; Muscle, Skeletal - blood supply; Muscle, Skeletal - enzymology; Muscle, Skeletal - transplantation; Nitroblue Tetrazolium; Orthopedic surgery; Oxidoreductases - analysis; Perfusion - methods; Rats; Rats, Sprague-Dawley; Regional Blood Flow - physiology; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgical Flaps - blood supply; Tissue Preservation - methods; Transplantation, Autologous; Rat; Rodentia; Citrate; Tolerance; Transplantation; Experimental study; Homotransplantation; Optimization; Blood; Vertebrata; Chemotherapy; Mammalia; Ischemia; Perfusion; Surgery; Animal; Free flap; Glycosaminoglycan; Circulatory system; Heparin; Prolonged
• ISSN: 0738-1085; 1098-2752
• DOI: 10.1002/(SICI)1098-2752(1999)19:3<135::AID-MICR3>3.0.CO;2-Y

This study investigated the use of heparinized and/or citrated whole blood as a perfusate for enhancing muscle tolerance to warm ischemia. Unilateral cutaneous trunci muscle flaps were harvested from Sprague‐Dawley rats and stored for 10 hr at 22–24°C prior to transplantation to the groin. One group served as a non‐perfused control. In three experimental groups, the flaps were hand‐perfused ex vivo with 1.0 ml of heparinized, citrated, or heparinized and citrated autogenous whole blood at physiological pressures. Perfusion was administered over a 10‐min period 5 hr into the ischemic period. Flaps were revascularized on the femoral vessels and then harvested 48 hr following revascularization. Tissue injury was assessed by calculation of flap weight change (indicator of tissue edema), histochemical evaluation of muscle dehydrogenase activity (nitroblue tetrazolium assay), and light microscopy. All perfused groups had significantly higher muscle dehydrogenase activity compared with non‐perfused controls (P < 0.005). Perfusion with combined heparin‐citrated blood was significantly more protective than perfusion with either anticoagulant alone (P < 0.025). The only statistically significant reduction in percent flap edema was seen in the combined heparin‐citrate perfusion of flaps compared with non‐perfused controls (P < 0.05). Histologic evaluation confirmed a reduction in tissue edema in the perfused flaps. We conclude that mid‐ischemic perfusion with heparinized and/or citrated blood limits the deleterious effects of extended warm ischemia. © 1999 Wiley‐Liss, Inc. MICROSURGERY 19:135–140 1999