Transanal laser Doppler flowmetry to assess microcirculation in the upper rectum during abdominal aortic aneurysmectomy.

PURPOSE: Fatal ischemic colitis can develop after abdominal aortic aneurysmectomy. We investigated the effectiveness of transanal laser Doppler flowmetry (LDF) for assessing microcirculation in the rectal mucosa during aneurysm repair.

METHODS

The subjects were 17 patients who underwent abdominal aortic aneurysmectomy. A Doppler laser and Doppler probe were mounted on a rectoscope, which was inserted into the anus, and rectal flux values were obtained by a flowmeter.

RESULTS

The mean flux value during aortic clamping was 146 +/- 35.6 perfusion units (PU) in patients with sufficient collateral circulation to the upper rectum and 58.3 +/- 19.4 PU in patients with insufficient collateral circulation ( P << 0.01). The LDF values and inferior mesenteric artery stump pressure measurements were well correlated ( r = 0.86).

CONCLUSION

Transanal rectal LDF is useful for continuously assessing microcirculation in the rectal mucosa during abdominal aneurysmectomy, and the data obtained with this method may reflect whether a collateral pathway to the upper rectum exists.