A comparison of injected lidocaine 2% and no analgesia for peripheral intravenous cannula insertion in the emergency department

Introduction

Many patients who present to the emergency department require placement of a peripheral intravenous line, which frequently causes pain and anxiety. We compare pain and anxiety associated with peripheral intravenous cannula insertion after pretreatment with no local anaesthesia or subcutaneously injected, buffered 2% lidocaine.

Methods

In a randomized study, peripheral intravenous cannulas were inserted in 185 patients arriving in the emergency department. In random order, insertion sites were pretreated with nothing or injected, buffered lidocaine. After each intravenous insertion, subjects recorded pain, anxiety, and preference (as patient and provider) for each technique on a 10-point numeric rating scale. Higher scores indicated greater pain, anxiety and preference.

Results

Median pain scores were 7 (5 to 8) without local anaesthesia and 1 (1 to 2) with injected, buffered lidocaine. Median anxiety scores were 4 (3 to 7) without local anaesthesia and 2 (1 to 3) with injected, buffered lidocaine. Most intravenous placement attempts were successful, regardless of technique. Eighty-seven per cent of subjects indicated they would always request buffered lidocaine for peripheral intravenous insertion. In the emergency department or other busy practice setting, injected, buffered lidocaine has the advantage of being immediately effective.

Conclusions

Pain and anxiety associated with peripheral intravenous insertion is significantly reduced by using topical injected, buffered lidocaine. Injected, buffered lidocaine reduces intravenous insertion pain more than pretreatment with no local anaesthesia, without affecting success.