Alert on the use of anesthesia in Venezuelan patients: What is known and why it is under investigation

Medical societies in the country have issued an alert about possible risks associated with the use of general anesthesia in patients of Venezuelan ancestry. The situation arose after reports of serious and unexpected cases initially recorded in Latina America and later identified in Europe and the United States.

The American Society of Anesthesiologists (ASA) and the Society for Pediatric Anesthesia (SPA) updated in April 2026 their recommendations on a number of adverse events, including severe neurologic damage, basal ganglia infarctions and deaths following anesthetic procedures considered routine.

Although the medical organizations insist that there is still limited and developing information, they believe that "the severity of these cases warrants developing and sharing expert opinion."

How the alert began

The first reports were communicated by South American anesthesiology societies. According to subsequent publications, cases of Venezuelan children suffering severe neurological complications after surgeries without apparent incident in Chile were reported in 2025.

Subsequently, El Nacional of Venezuela reported, medical associations in Spain, the United States and other countries began to identify similar episodes in patients of Venezuelan origin.

In this regard, the ASA and SPA pointed out that much of the available clinical information "has been shared only through personal communication or non-peer-reviewed publications." so they emphasize that many conclusions remain preliminary.

The pattern detected by the physicians

According to the family histories compiled by the medical societies, all of the patients analyzed were of Venezuelan descent through the maternal line and several had a family history of anesthetic complications.

"Almost all the affected patients are reported to have received sevoflurane," the report states, although the organizations acknowledge that they do not have complete details on doses, concentrations or duration of anesthesia in each case.

Genetic testing of a subset of patients identified multiple mitochondrial mutations. The most studied so far is the "mtND4 m.11232 T>C" mutation, linked to complex I of the mitochondrial electron transport chain.

According to the ASA and SPA, complex I "is a known target of volatile anesthetics and is also known to be inhibited by propofol."

The paper adds that previous studies showed that "prior work has shown that impaired complex I activity correlates with hypersensitivity to volatile anesthetics in animals and humans."

What is known so far

Medical societies stress that patients carrying this mutation do not seem to present relevant symptoms prior to exposure to anesthesia.

Currently there is no rapid screening test for the ND4 mutation and the organizations acknowledge that it is still unknown what would be the safest anesthetic for this population.

"The optimal and safest anesthetic for patients with this ND4 mutation has not been established," the update notes.

However, because most of the reported cases were associated with sevoflurane use, the ASA and SPA recommended "avoiding the use of all volatile anesthetics until more information is available."

They also noted that some patients previously affected with sevoflurane-based anesthesia "have had uneventful propofol anesthetics," although they clarified that the safety of prolonged propofol use in this population is still unknown.

The ASA and SPA indicated that they will continue to gather information and update recommendations "based on the latest available evidence." In addition, they asked anesthesiologists and medical centers to report any similar cases to the Anesthesia Incident Reporting System (AIRS) to centralize the investigation of observed events.