Prevalence and Predictors of Prilocaine Induced Abnormal Methemoglobinemia During Cardiac Device Implantation Procedure

Aim: The aim was to determine the prevalence and predictors of prilocaine-induced methemoglobinemia during the cardiac implantable electronic device (CIED) implantation procedure. Methods: One hundred patients who underwent CIED implantation procedures under local anesthesia with prilocaine were included in the study. Patients were divided into two groups according to the percentage of methemoglobin (MetHb) in arterial blood gas analysis. Data regarding patients, laboratory, and procedure-related factors were compared between the two groups. Results: The mean age of the patients was 70.97 ± 11.54 years, and 42% were female. Based on the criterion of MetHb level above 3%, the prevalence of pathologic methemoglobinemia was 47%. Multivariate logistic regression analyses were performed to identify independent predictors for the development of prilocaine-induced abnormal methemoglobinemia. In multivariate analysis, the presence of low body mass index (BMI) and chronic obstructive pulmonary disease (COPD) (OR: 0.876; 95% CI 0.781-0.981; p=0.022 and OR: 5.170; 95% CI 1.535-17.411; p=0.008) independently predicted the development of abnormal methemoglobinemia. Conclusion: Abnormal MetHb levels were found in almost half of patients who underwent the CIED implantation procedure after subcutaneous prilocaine injection. Methemoglobinemia may occur even at doses lower than the recommended maximum dose, especially in patients with low BMI and COPD.