Reducing pain experienced during potassium chloride infusion in the emergency department

Aims: Patients with hypokalemia often complained of pain during intravenous potassium chloride infusion. By administrating ignocaine prior to the infusion, the pain experienced may be reduced but safety concerns have limited its clinical application. The primary objective was to determine the efficacy of lignocaine in reducing pain experienced during potassium chloride infusion in the Emergency Department. The secondary objective was to determine the adverse events associated with intravenous lignocaine use for this purpose.
Materials and Methods: Continuous quality improvement data were prospectively collected. The lignocaine protocol involved giving 30mg of 1% lignocaine intravenously 1 minute before starting the potassium chloride infusion. The decision to use this protocol was left to the discretion of the attending doctor when managing a patient with hypokalemia requiring intravenous replacement. The nurse taking care of the patient would record any experience of pain during the infusion. Occurrence of any adverse event was recorded.
Results: A total of 100 patients were recruited. After stabilized weights adjustment, the resultant sample size was 98, with 49 patients in each group. The proportion of patients experiencing pain was significantly higher when no lignocaine was given (38.8% vs 16.3%, p = 0.013). The absolute risk reduction was 22.5% and the relative risk of pain was 0.42 (0.20-0.87, p = 0.013). The numbers needed to treat was 5 (3-19).There was no adverse event associated with the lignocaine protocol in this study.
Conclusion: Intravenous lignocaine was efficacious and safe in reducing pain during potassium chloride infusion.