A sequential randomised controlled trial comparing a dry visco-elastic polymer pad and standard operating table mattress in the prevention of post-operative pressure sores.

Four hundred and forty-six general, vascular and gynaecological surgical patients were recruited to a two centre, double triangular sequential randomised controlled trial to compare the post-operative pressure sore incidence in patients positioned on the standard operating table mattress with those positioned on the dry visco-elastic polymer pad (Action Products Inc.). Two hundred and twenty two patients were randomised to the experimental group and 224 to the standard mattress. The main endpoint failure rate (a pressure sore) was found to be 11% (22/205) for patients allocated to the dry visco-elastic polymer pad and 20% (43/211) for patients allocated to the standard operating table mattress. There was a significant reduction in the odds of developing a pressure sore on the dry visco-elastic polymer pad as compared to the standard, [symbol see text] = 0.46 with 95% confidence interval of (0.26, 0.82), P = 0.010. The adjusted point estimates of the probability of developing a pressure sore on the dry visco-elastic polymer pad and the standard operating table mattress were 0.11 and 0.21 respectively.