Laser Doppler velocimetry and the measurement of colostomy blood flow.

Early colostomy closure leads to a high rate of fecal fistula formation which may be due to a poor blood supply. Laser Doppler flowmetry is a new method of measuring colonic blood flow. Blood flow in 17 colostomies has been measured at one week, median flux 28 units (range, 13 to 43) and in 12 colostomies more than eight weeks after formation, median flux 46 units (range, 35-56; P less than 0.002). Nine of the "mature" colostomies have been closed without a fecal fistula or other signs of anastomotic failure. Serial readings of colostomy blood flow were made at weekly intervals in another ten stomas over a period of two months. Blood flow increased over this time from a median of 19 units (range, 17 to 22) at one week to a median of 44 units (range, 39 to 48; P less than 0.002) at eight weeks. Laser Doppler flowmetry is a simple, noninvasive method of measuring colostomy blood flow and the findings support a clinical policy for delayed colostomy closure.