Calf compartment pressures in the Lloyd-Davies position: a cause for concern?

Lower limb compartment syndrome is a rare consequence of surgery where the lithotomy position is maintained for several hours. The aim of this study was to observe the effect of the lithotomy position on lower limb compartment pressure and blood flow to the lower limb in surgical patients having colorectal procedures. We prospectively studied 23 patients undergoing colorectal surgery requiring the lithotomy position and recorded lower limb compartment pressure, and the blood pressure in the upper and lower limbs. The lithotomy position led to a significant (p < 0.001) fall in blood pressure to the lower limb from 87 (SD 16) mmHg to 67.9 (SD 12) mmHg and a significant (p < 0.001) rise in lower limb compartment pressure from 13 (SD 7) mmHg to 31 (SD 12) mmHg. These two effects compromise blood flow to the lower limb in long surgical procedures where the lithotomy position is required. Intermittently lowering the legs and restoring blood flow may prevent compartment syndrome developing.