Adaptive skin blood flow increases during hip-down lying in elderly women

Pressure ulcer development due to unrelieved pressure during extended cardiovascular, orthopedic, and other procedures is an important clinical problem. Because blood flow changes within pressure-loaded tissue affect the skin breakdown process, the relative effects of 2 support surface strategies on trochanter skin blood flow were investigated.

Skin blood perfusion was assessed by laser Doppler methods during 1 hour of continuous loading. Blood perfusion was measured before and during hip-down loading on a gel pad (static surface) and a dynamic multisegmental surface that provided periodic alternating pressure relief. Female volunteers (N = 20, age > or = 60 years) were tested on each surface in random order with sequential tests separated by 5 to 8 days. Effects were assessed by comparing perfusion during the first and last 15 minutes of hip-down loading with a 15-minute baseline.

Research center.

Pre-load perfusions (dynamic vs static support) were similar (0.57 +/- 0.06 vs 0.64 +/- 0.08). During loading, however, a significant progressive increase in perfusion was noted only with dynamic support; by the end of the loading interval, this increase in perfusion had significantly exceeded the pre-load baseline (1.22 +/- 0.26, P = 0.001).

These findings reveal a surface-dependent blood flow impact, with the multisegmental dynamic approach being associated with greater flow during loading. The mechanism, though speculative, is consistent with a greater vascular adaptation potential offered by the dynamic surface. Conditions that facilitate such adaptive flow increases would appear to be of considerable benefit in helping to prevent ulcer development.