Ankle Brachial Index Predicts for Difficulties in Performing Microvascular Anastomosis

In reconstructive microsurgery, severe arteriosclerosis is a known predictor for free flap failure because of problems with the vascular anastomosis. We investigated whether the ankle brachial index (ABI) could be a suitable preoperative measurement for the prediction of compromise regarding vascular anastomosis in patients undergoing microsurgical reconstruction.

We conducted a prospective cohort study of patients who had undergone reconstructive microvascular surgery in a tertiary care center from 2015 to 2017. The ABI was preoperatively assessed by dividing the systolic blood pressure measured at the ankle by the brachial systolic blood pressure. Results from 0.9 to 1.3 are within the physiologic range. Values less than 0.9 indicate moderate to severe arteriosclerosis, and those greater than 1.3 indicate the major form of arteriosclerosis with complete calcification of the tunica media. The ABI value correlated with the ease of the anastomosis (rated from 1 [very straightforward] through 5 [very difficult]), gross examination findings (intraluminal plaque [yes vs no]), and the necessity of plaque removal before anastomosis (yes vs no). In addition, cross-sectional specimens were obtained from the arteries and veins of the donor and recipient sites intraoperatively. The specimens were rated histologically for the arteries and veins using an ordinal scale. Histologic evaluation was performed to confirm and objectify the results from the ABI. Statistical analysis was performed using SPSS software, version 24.0 (IBM Corp, Armonk, NY) and t tests, analysis of variance, and χ² tests.

The sample included 41 patients with a mean age of 56.7 years; 59% were men. The mean ABI was 1.06. The mean ease of anastomosis was 1.8. The mean ABI was associated with the ease of anastomosis. A pathologic ABI was significantly related to problems with the arterial anastomosis (P = .004) and increased arteriosclerosis in the arteries from the donor (P = .047) and recipient (P = .036) sites.

A pathologic ABI was associated with increased difficulty with the microvascular anastomosis.