Improvement in pain and patient comfort during injection of local anaesthesia with the use of sodium bicarbonate

Abstract

BACKGROUND: The beneficial effect of adding 8.4% sodium bicarbonate (NaHCO3) to local anaesthesia, making it less painful to inject, is documented in the literature. However, few doctors actually put this knowledge into practice. With this study, we quantify this effect in the Maltese population and justify its use in our day to day practice. In addition, we take this opportunity to elaborate on the additional factors that improve patient comfort when injecting local anaesthesia.

METHOD: A total of 150 patients having a procedure under local anaesthesia at the Plastic Surgery and Burns Unit, at Mater Dei Hospital, Malta, were included in this study. 75 patients were injected with lidocaine alone and another 75 patients were injected with lidocaine mixed with 8.4% sodium bicarbonate.

RESULTS: The commonest age group was the 70-79 age group in both cohorts. The minimum pain score was 0 in both groups. The highest score was 9 in the group without sodium bicarbonate and 8 in the group with sodium bicarbonate. The mean pain score was 3.93 in the cohort without sodium bicarbonate and 2.55 in the cohort with sodium bicarbonate. The median value was 4 in the group of patients injected without sodium bicarbonate and 2 in the group injected with sodium bicarbonate. The p-value was <0.5, making these results statistically significant.

CONCLUSION: Alkalinisation of local anaesthetic solutions improves the pain of infiltration of the local anaesthetic at a minimal cost. This increases patient compliance and patient comfort and thus allowing more surgeries to be performed under local anaesthesia.