Evaluation of indirect blood pressure measurement as a method of assessment of peripheral vascular disease
Quin, R.O.; Evans, D.H.; Fyee, T.; Bell, P.R.
Journal of Cardiovascular Surgery 18(2): 109-116
1977
ISSN/ISBN: 0021-9509 PMID: 856823 Document Number: 121574
In over 200 patients with peripheral vascular disease, pressure index (formula: see text) was compared with radiological grade; although calf P.I. had a better correlation, there was wide overlap between the groups. In 28 patients, resting calf P.I. was compared with functional impairment measured on a treadmill. At two rates of exercise, calf P.I. correlated poorly with functional impairment. In 35 patients, reproducibility of indirect pressure measurement was assessed; coefficients of variation ranged 0-10%; coefficient of variation of calf P.I. ranged 0-8%; coefficient of variation of calf P.I. ranged 0-8%. In 12 patients, indirect thigh systolic pressure was compared with and nearly always exceeded direct common femoral artery pressure; this was due to an effect of the cuff which reduced blood flow and reduced the pressure gradient. This methodological error has not previously been described and reduces the clinical value of the measurement.