Case Report: Dynamic characteristics of myocardial depression after severe bupivacaine-induced local anesthetic systemic toxicity

Background: Bupivacaine-induced local anesthetic systemic toxicity (LAST) can lead to severe myocardial depression and circulatory collapse, and some patients may require venoarterial extracorporeal membrane oxygenation (VA-ECMO) support. However, serial and visually interpretable clinical data regarding the dynamic changes in cardiac function, the timing of the nadir, and the recovery trajectory of severe bupivacaine-induced myocardial depression remain limited. Case presentation: A 32-year-old woman at term underwent combined spinal-epidural anesthesia. Shortly after intrathecal administration of 2.0 mL of 0.5% bupivacaine, she developed sacrococcygeal numbness, limb tremors, and bilateral lower-limb convulsions, followed by rapid progression to severe circulatory collapse. Bedside echocardiography revealed markedly impaired left ventricular systolic function, with a left ventricular ejection fraction (LVEF) of approximately 27%. Despite treatment with lipid emulsion and vasoactive agents, hemodynamic stability could not be maintained, and VA-ECMO support was therefore initiated. Serial bedside echocardiography showed that cardiac function reached its nadir 24 h after symptom onset, with a stroke volume of 10.4 mL and an LVEF of 13.2%. Cardiac function then remained at a low-level plateau for the following several days and showed marked recovery approximately 120 h after onset, meeting the criteria for ECMO weaning. After decannulation, cardiac function continued to improve, and the patient was successfully extubated and transferred to the obstetrics department for further management. Conclusions: Severe bupivacaine-induced myocardial depression may be characterized by a delayed functional nadir followed by a reversible recovery process. VA-ECMO can provide effective circulatory support for cardiogenic shock refractory to conventional therapy. Serial bedside echocardiography may help assess the trajectory of cardiac recovery and guide the timing of ECMO weaning.