A comparison of Rapydan® patch and Ametop® gel for venous cannulation

Ametop(®) gel (4% tetracaine) is used to provide topical anaesthesia for venous cannulation. Rapydan(®) patch (7% lidocaine and 7% tetracaine) has been developed to provide topical anaesthesia by a different mechanism, that of heat assisted delivery. We compared the topical anaesthetic effect of these agents for venous cannulation. One hundred healthy adults undergoing day-case surgery were randomly assigned to receive either Rapydan (n = 50) or Ametop (n = 50) before venous cannulation. Pain on insertion was scored on a visual analogue scale between 0 and 100 (where 100 = unbearable pain). Median(IQR[range]) pain scores were not different between groups with 11 (5-20 [0-72]) for Rapydan and 10 (5-24 [0-95]) for Ametop (p = 0.63). Adequate topical anaesthesia was achieved in over 90% of patients in both groups. Rapydan produces topical anaesthesia comparable with Ametop for venous cannulation.