Altered postural regulation of foot skin oxygenation and blood flow in patients with type 2 diabetes mellitus

Exp Clin Endocrinol Diabetes. 2007 Jul;115(7):444-7. doi: 10.1055/s-2007-960499.

Abstract

Aims: Although skin oxygenation is an important factor in the development and healing of foot ulcers, its regulation was not fully understood. We studied changes in foot skin oxygenation and blood flow during postural changes in patients with type 2 diabetes mellitus.

Methods: Skin oxygenation was measured using transcutaneous oxygen pressure (TcPO(2)) and skin blood flow by laser Doppler flowmetry in 40 patients with type 2 diabetes mellitus without evidence of peripheral arterial disease and 13 healthy control subjects.

Results: TcPO(2) in the supine position was significantly lower in patients with type 2 diabetes mellitus compared with control, although skin blood flow was not different. In the sitting position, TcPO(2) significantly increased in control and diabetic patients. The postural change-related increase in TcPO(2) was significantly enhanced in diabetic patients. On the other hand, skin blood blow significantly decreased in the sitting position from the supine position in control subjects but remained stable in diabetic patients. Orthostatic drop in systolic blood pressure correlated negatively with TcPO(2) in the supine position while correlated positively with %change in TcPO(2) and blood flow by postural changes.

Conclusions: The present study demonstrated the dissociated regulation of skin oxygenation and blood flow in response to leg dependency. Impaired postural vasoconstriction was associated with altered regulation of skin oxygenation probably due to sympathetic vascular dysfunction in diabetic patients.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Blood Pressure
  • Case-Control Studies
  • Diabetes Mellitus, Type 2 / complications
  • Diabetes Mellitus, Type 2 / metabolism
  • Diabetes Mellitus, Type 2 / physiopathology*
  • Diabetic Foot / metabolism
  • Diabetic Foot / physiopathology*
  • Foot / blood supply*
  • Humans
  • Middle Aged
  • Oxygen Consumption*
  • Posture / physiology*
  • Regional Blood Flow
  • Skin / blood supply
  • Skin / metabolism*