The impact of transcutaneous oxygen pressure measurement in patients with suspected critical lower limb ischemia.

BACKGROUND: Our aims were to describe macro- and microvascular disease by the use of a combination of toe blood pressure (TBP) and transcutaneous oxygen pressure (TcPO2) measurements, and through this approach we aimed to classify lower limb ulcers. One specific aim was to evaluate whether patients with diabetes had a more pronounced disturbance of the microcirculation compared to patients without known diabetes.

METHODS: The study included a series of 498 patients with suspected critical lower limb ischemia. All patients were investigated with TBP and TcPO2, and the macro- and microvascular function was graded as normal, reduced or critically reduced.

RESULTS: Four hundred and twenty-two patients (85%) had ulcerations at the time of the examination, the same percentage in patients with (254/300) and in patients without diabetes (168/198). Dominantly microvascular disease with TcPO2 more reduced than TBP was seen in 18% (54/300) of the diabetic, and in 17% (33/198) of the non-diabetic patients. In the diabetic patients the lower limb ulcerations were as following: 44% ischemic, 47% mixed and 9% non-ischemic, respectively. In the non-diabetic patients the corresponding numbers were 38%, 52% and 10%.

CONCLUSIONS: By combining TBP and TcPO2 the degree of macro- and microvascular dysfunction can be evaluated, classification of lower limb ulcers will be facilitated and the risk of underestimation of the degree of distal ischemia will be reduced. Microvascular dysfunction is as common in non-diabetic patients, as it is in patients with diabetes.