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

OBJECTIVE

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.

DESIGN

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.

SETTING

Research center.

RESULTS

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).

CONCLUSION

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.