Combined superficial peroneal and saphenous nerve block for ascending venography

Needle insertions into the veins of the dorsum of the foot are an overlooked source of pain and discomfort during ascending venography. As a solution to this problem a regional anaesthetic technique is presented, the combined superficial peroneal and saphenous nerve block, after being studied prospectively on 42 patients referred for bilateral venography. The nerve blocks were always performed unilaterally. At the end of each bilateral study patients were asked to express a preference for one of the two venograms, on the basis of pain and discomfort from the needle insertions. Of the 42 patients, 27 (64.3%) opted for venography with regional anaesthesia, 9 (21.4%) for venography without regional anaesthesia, while 6 (14.3%) did not state a definite preference. As shown by the sign test, preference for venography with venography with regional anaesthesia was highly significant. By observing the reactions of the patients during the needle insertions, the radiologist classified arbitrarily the pain produced in each individual venogram as minimal, moderate or severe. The statistical significance of these observations was verified with the chi-squared test for trend and the sign test. In addition to diminishing effectively the pain from the venography needle, this simple technique proved to be safe and causing negligible discomfort. It is recommended for all patients who are apprehensive or have already experienced considerable pain on a first unsuccessful venipuncture attempt, or when multiple punctures are expected because of lack of suitable veins or presence of oedema.