Inferior mesenteric artery stump pressure is an unreliable predictor of the outcome of colorectal anastomosis

Abstract

Ankle/brachial pressure is used as a predictor for the outcome of femoro-popliteal bypass. It has been suggested that a mean inferior mesenteric artery stump pressure (IMASP) below 40 mmHg after aortic reconstruction may be similarly predictive of postoperative ischemic colitis. No previous report has considered IMASP as a predictor of the integrity of colorectal anastomosis. The aim of the study is to examine the correlation between IMASP and anastomotic leakage rate after left colectomy. From April 2004 to March 2006, 99 patients undergoing left colon resection by a single surgeon were measured for their IMASP and arm systemic pressure (SP). All but two patients were operated for carcinoma of the colon or rectum. Sixty-nine patients had primary anastomosis without diverting stomies. The stump mean pressure varied from 24 to 75 mmHg. Seventy-nine patients (79.8%) had pressures equal or above 40 mmHg. IMASP/SP ratios ranged from 0.21 to 0.7. Sixty-seven patients (67.7%) had IMASP/SP ratios equal or above 0.4. Two patients were found to have postoperative leakage of anastomosis. Their IMASP were 35 and 70 mmHg, and their IMASP/SP ratios were 0.28 and 0.62, respectively. We could not identify a significant difference between the two groups, and the pressure of the inferior mesenteric artery could not be proven to be a relevant predictor of anastomotic leakage. This series suggested that IMASP lower than 40 mmHg or an IMASP/SP ratio less than 0.4 does not correlate with an increased leakage rate. Neither IMASP nor the IMASP/SP ratio is a reliable indicator for predicting the outcome of colorectal anastomosis.