Objectives In the United Kingdom, approximately eight million peripheral cannulations are performed each year. Intravenous cannulae are made from either polytetrafluoroethylene (Teflon®) or polyurethane. Polyurethane has a lower incidence of thrombophlebitis, however the physical characteristics of polyurethane may make the cannulae difficult to use at higher ambient temperatures. This effect maybe of importance to those involved in cannulation in extreme environments and especially for military doctors deployed in current theatres of operations.

Methods In a randomised single blinded study we investigated the different characteristics of Teflon® and polyurethane cannulae (Vasofix® Safety Cannulae, B Braun) at three different temperatures (-10ºC, 21ºC and 40 ºC).

Results There is no statistically significant difference in the ease or speed of cannulation of either polyurethane or Teflon® safety cannulae in extremes of temperature.

Conclusions This study provides evidence that performance of polyurethane safety cannulae are not impaired by temperature extremes.