A comparison of irrigation solutions for microanastomoses

A comparative study of irrigating solutions that contained various clot-active substances and/or vasodilating substances was done using a crush injury model of the rat's femoral artery. A routine microanastomosis was done with one of seven irrigation solutions employed in the study. The patency rate of lactated Ringer's solution (10%) (the control solution) was compared with solutions of heparin (35%) urokinase (50%), phentolamine (35%) tissue plasminogen activator (tPA) (15%), a combination of urokinase, heparin, and phentolamine (55%), and a combination of tPA, heparin, and phentolamine (42.5%). Statistically significant improvement in patency rates were obtained with heparin (p less than 0.0005), phentolamine (p less than 0.03), urokinase (p less than 0.001), the tPA, heparin and phentolamine combination (p less than 0.001), and the urokinase, heparin, and phentolamine combination (p less than 0.0001). There seems to be a benefit with the addition of either vasoactive agents or clot-active agents to the microvascular irrigating solution during construction of a compromised microanastomosis.