Authors of this study set out a randomized, controlled study to determine the change in pain levels when administering warm or refrigerated local anaesthetic.
This study was measuring pain levels when using lignocaine with adrenaline as the local anaesthetic, either at room temperature or at a refrigerated temperature.
50 patients took part in this study, all of whom required open carpal tunnel decompression surgery on one of their hands. The mean age of the patients was 64years. Each participant was randomized to receive either room temperature or refrigerated local anaesthetic.
Pain experienced immediately after the injection was assessed using the VAS scale (Visual Analogue Scale), with zero (0) being no pain and ten (10) meaning maximal pain.
Results showed the VAS score for local anaesthetic being administered at room temperature was 4.0 and was 6.5 for refrigerated.
This study demonstrates when administering lignocaine with adrenaline to patients, refrigerated temperatures can cause increased pain levels.
It is suggested therefore, that this combination of local anaesthetic should be left to reach room temperature before administering it to patients.
Mike Hayton routinely uses local anaesthetic at room temperature and will continue to do so; however was interested to learn the effects when using it at refrigerated temperatures.
P.J. Tomlinson and J. Field
The Journal of Hand Surgery (European Volume, 2010)
From the Department of Orthopaedics, Cheltenham General Hospital, Cheltenham, Gloucestershire, UK.