Digital ischaemia after ulnar artery cannulation

Abstract

Editor—Arterial cannulation is frequently undertaken in major surgery and in intensive care. After failure to cannulate the radial artery at the wrist, cannulation of the ipsilateral ulnar artery has been performed uneventfully.1Slogoff S Keats AS Arlund C On the safety of radial artery cannulation.Anesthesiology. 1983; 59: 42-47Crossref PubMed Scopus (288) Google Scholar The presence of an indwelling arterial catheter may lead to ischaemic damage, which is sometimes permanent. We recently experienced this complication following ulnar artery catheterization. To our knowledge, this has not been reported previously. A 76-yr-old woman was admitted to our intensive care unit following laparotomy. After unsuccessful attempts to cannulate the left radial artery, a catheter was finally inserted into the left ulnar artery (Vygon Leader Flex 20G catheter, length 8 cm). We did not cannulate the right radial artery or the femoral arteries as these had been cannulated recently. Six days after cannulation, it was noticed that the tips of the left index, middle and little fingers had become cyanotic and cold (Fig. 1). The arterial catheter was removed immediately. The patient was given a bolus of heparin 5000 U i.v. followed by an i.v. infusion of heparin 1000 U h−1. The patient had not experienced any pain or neurological deficit in the hand. Circulation to the fingers gradually improved and eventually recovered fully. A number of factors may contribute to ischaemia following arterial cannulation. These include emboli originating from a proximal site,2Vender JS Watts DR Differential diagnosis of hand ischaemia in the presence of an arterial cannulation.Anesth Analg. 1982; 61: 465-468Crossref PubMed Scopus (8) Google Scholar prolonged cannulation, and severe local trauma.3Wyatt R Glaves I Cooper DJ Proximal skin necrosis after radial artery cannulation.Lancet. 1974; 1: 1135-1138Abstract PubMed Scopus (30) Google Scholar The other factors associated with increased risk of arterial occlusion are female sex, and low cardiac output.4Davis FM Stewart JM Radial artery cannulation. A prospective study in patients undergoing cardiothoracic surgery.Br J Anaesth. 1980; 52: 41-47Crossref PubMed Scopus (94) Google Scholar This incident shows that ulnar artery cannulation following failure to cannulate the ipsilateral radial artery may increase the risk of arterial insufficiency and should therefore be discouraged, unless any alternative is available. Before this procedure continuing blood flow through the radial artery should be demonstrated (e.g. by a reverse Allen's test, digital plethysmography, or Doppler studies. In this case, the risk was further augmented by the fact that the catheter was left in situ for 6 days. The patient's hand should be examined regularly if an arterial catheter has been inserted. If signs of arterial occlusion occur, the cannula should be removed promptly and appropriate anticoagulant treatment given without delay.