Ankle:brachial pressure index (ABPI) measurements are often performed by junior medical staff with little experience of the technique. The accuracy of such measurements is unknown. Two newly qualified doctors with no training in the use of Doppler ultrasonographic flowmeters performed ABPI measurement in 38 limbs (experiment 1). Two other newly qualified doctors then underwent a formal training session before, as well as continuous instruction during, ABPI measurements in 23 limbs (experiment 2). The doctors' measurements were compared with those obtained by experienced vascular technicians. The mean difference in ABPI measurement between the doctors and technicians in experiment 1 was greater than that in experiment 2 at both the dorsalis pedis (P < 0.05) and posterior tibial arteries. Nearly 30 per cent of the doctors' ABPI measurements in experiment 1 differed from those of the technicians by more than 0.15, in comparison with only 15 per cent of the measurements performed in experiment 2. Junior doctors should undergo formal training before performing ABPI measurements.

Hypercoagulable states are found in up to 10 per cent of patients with a history of unexplained venous thrombosis. To investigate the prevalence in arterial thrombosis, thrombophilia screening was performed on 124 patients who had previously undergone lower-limb revascularization, 45 claudicants and 27 controls. Of the patients who had undergone revascularization 40 per cent had a hypercoagulation abnormality (low levels of protein C, protein S and antithrombin III or presence of the lupus anticoagulant) in comparison with 27 per cent of claudicants and 11 per cent of controls (P < 0.01). Furthermore, patients who had suffered reocclusion after revascularization were significantly more likely to have a hypercoagulation abnormality than those who had not (P < 0.05), even if the occlusion had occurred more than 6 months previously. Lupus anticoagulant was the abnormality most frequently detected and, like low protein C levels, was found only in patients with peripheral vascular disease. It appears that hypercoagulable states are common in patients with arterial disease and may predispose to failure of revascularization.

Microcirculatory assessments performed in patients with limb-threatening ischaemia are likely to be more deranged in those patients who suffer clinical failure or amputation despite an apparently successful revascularisation procedure.