(1067) From Anesthesia to Adversity: A Case Report on Lidocaine Anesthetic Systemic Toxicity (LAST)

Introduction: Lidocaine Anesthetic Systemic Toxicity (LAST) is a rare but life-threatening adverse reaction to lidocaine, occurring in approximately 0.2% of cases. It typically manifests within minutes of injection and can also result from inadvertent injection into the systemic circulation or rapid absorption from highly vascular areas. Exceeding the maximum recommended dose of lidocaine significantly increases the risk of LAST.

Description: A 62-year-old male with a medical history of diabetes, obesity, and hypertension presented to the emergency room with symptoms of shortness of breath, fatigue, and dyspnea on exertion. Imaging revealed a large right pleural effusion. A thoracentesis was performed at the bedside using Point-of-Care Ultrasound (POCUS) for guidance. Lidocaine 1% (20 ml) was administered subcutaneously for local anesthesia. During the procedure, 1,500 ml of fluid were drained and sent for pathology.

Later in the day, the patient experienced status epilepticus and required Advanced Cardiac Life Support (ACLS) with intubation. Given the high dose of lidocaine administered and the subsequent development of neurological symptoms, LAST was identified as the likely etiology. The patient was promptly managed with aggressive supportive care, including benzodiazepines for status epilepticus and vasopressors due to shock. Due to timely recognition and management of LAST, the patient’s condition improved, and he made a recovery.

Discussion: Lidocaine Anesthetic Systemic Toxicity is a rare but potentially fatal condition necessitating a rapid and multifaceted response. The use of cognitive aids and simulation training can significantly enhance preparation and management in such critical situations. We clinicians must have this adverse effect in mind since Thoracentesis is a regular procedure in our daily basis.