Anesthesia Risks: Alert for Patients of Venezuelan Descent – US Medical Societies

Health Alert: Rare Genetic Mutation Linked to Anesthesia Risks in Patients of Venezuelan Descent

International medical associations have issued an alert following reports of severe and unexpected complications, including severe neurological damage and death, in healthy adult and pediatric patients of Venezuelan ancestry after receiving general anesthesia. The alerts began surfacing in late 2025 and have continued into February 2026.

The American Society of Anesthesiologists (ASA) and the Society for Pediatric Anesthesia (SPA) jointly issued an updated communication on January 28, 2026, regarding these cases. Initial reports originated from anesthesia societies in South America, with subsequent cases identified in Europe and the United States. While much of the clinical information remains preliminary and hasn’t been published in peer-reviewed studies, the severity of the outcomes prompted the ASA and SPA to share expert opinions.

Detailed family histories taken from affected patients revealed a common thread: all patients had Venezuelan heritage and several had family members who experienced adverse outcomes following otherwise routine anesthesia. Approximately 40 cases have been identified worldwide, with six to eight in the United States.

Genetic Mutation Identified

Genetic testing on a subset of patients revealed a genetic mutation in mitochondrial DNA, specifically the ND4 mutation. This mutation affects the complex I of the mitochondrial respiratory chain. The ND4 mutation is inherited directly from the mother, meaning any patient with direct maternal Venezuelan lineage should be considered at risk.

According to the ASA and SPA, the complex I is known to be a target of volatile anesthetics and is also inhibited by propofol. Reduced activity of complex I has been linked to hypersensitivity to anesthetics in both animal and human studies.

Anesthetics Involved

Almost all affected patients reportedly received sevoflurane, a commonly used volatile anesthetic, though specific details regarding dosage and duration are currently unknown. A few patients reportedly received propofol infusions without incident. Experts emphasize that the limited data makes it impossible to determine which anesthetics may pose the greatest risk.

Chilean Cases and Investigation

In July 2025, the Chilean Ministry of Health reported the deaths of five children between 2021 and 2025, all with maternal Venezuelan ancestry. While Chilean authorities cautioned against establishing a causal link at that time, they noted a potential association with a mitochondrial variant of complex I.

Following the Chilean reports, the Venezuelan Society of Anesthesiology called for a thorough investigation, while the Colombian Society of Anesthesiology and Resuscitation urged caution and scientific rigor, emphasizing the dangers of attributing risk based on nationality without validated evidence.

Recommendations for Anesthesiologists

The ASA and SPA recommend that anesthesiologists consider asking patients about potential maternal Venezuelan heritage. However, they stress that a negative family history of anesthetic complications does not eliminate the risk posed by this genetic mutation.

The societies advise handling discussions about Venezuelan ancestry and associated explanations with care and sensitivity. They also recommend consulting with genetics specialists and obtaining informed consent before conducting mitochondrial DNA sequencing to confirm the presence of the ND4 mutation.

Managing Anesthetic Exposure

Currently, there is no identified “safe” anesthetic for patients carrying this mutation. The ASA and SPA suggest considering avoiding volatile anesthetics and exploring regional anesthesia techniques when appropriate. They also recommend heightened monitoring during and after procedures, with prolonged postoperative neurological observation if any concerns arise.

The ASA and SPA emphasized that these recommendations are being issued in a context of ongoing uncertainty and will be updated as new scientific information becomes available. They acknowledge the need for further research to fully understand the risks and develop optimal management strategies for patients with this genetic predisposition.