HYPERTONIC SALINE INFUSION WITH OR WITHOUT DEXTRAN-70 IN THE REPERFUSION PHASE OF EXPERIMENTAL ACUTE LIMB ISCHEMIA

Objectives: To study the efficacy of hypertonic fluid therapy on centr al haermodynamics, leg blood flow, and skeletal muscle metabolism at r eperfusion after subtotal bilateral limb ischaemia. Design: Prospectiv e, randomised, controlled study, in pigs (n=24). Methods: Bilateral li mb ischaemia was induced (aortic balloon catheter) and centr al haemod yamamics, peripheralal blood flow, thoracic fluid content, blood chemi stry, and skeletal muscle metabolite levels were monitored. After 235 min of ischaemia infusion of normal 0.9% saline (NS), hypertonic 7.5% saline (HS), or HS in 6% dextran 70 (HSD) was started. Five minutes la ter the aortic balloon was deflated and the haemodynamic and metabolic alterations were studied for 180 min after reflow. Results: Aortic oc clusion resulted in haemodynamic alterations, reduced limb perfusion a nd metabolic changes indicative of tissue ischaemia. The haemodynamic support prior to, and following, deflation of the aortic balloon was m ore efficient for HS and HSD than for NS. Lactate clearance and restit ution of high energy phosphagen levels in skeletal muscle were faster and more pronounced in the HS and HSD groups Conclusions: Small-volume hypertonic saline, especially in combination with 6% dextran 70, will effectively reverse limb ischaemia-induced haemodynamic and tissue me tabolic disturbances.