Blood flow in small arteries after end-to-end and end-in-end anastomoses: an experimental quantitative comparison

Microvascular anastomoses were performed under standardized conditions on the central artery of the ear in 23 rabbits. Fifteen end-to-end and 13 end-in-end anastomoses were compared. No anticoagulants or vasodilating agents, other than the local application of lidocaine, were used. Blood flow was measured by electromagnetic flowmetry before anastomosis and after anastomosis at intervals of 30 minutes for 4 hours and at 1 and 3 days. The validity of the electromagnetic flowmetry method was established in a control group of 7 rabbits. The mean volume of blood flow after end-to-end anastomosis was 93% of the preoperative value (P greater than 0.05). The corresponding mean volume of blood flow after end-to-end anastomosis was 47% of the preoperative value (P less than 0.001). The difference in flow between end-to-end and end-in-end anastomosis was highly significant (P less than 0.001). Microangiography demonstrated marked stenosis in the end-in-end anastomoses but not in the end-to-end anastomoses.