MOC-Etomidate: Retaining Beneficial Anesthetic Properties, Reducing Dangerous Side Effects

Newswise — Researchers at Massachusetts General Hospital (MGH) have developed a new anesthetic agent, which they think could be a breakthrough in the quest to discover drugs that retain beneficial anesthetic properties while reducing unwanted and occasionally dangerous side effects.

Douglas E. Raines, M.D., and his colleagues from the MGH Department of Anesthesia, Critical Care and Pain Medicine believe that the new drug, MOC-etomidate, could prove to be beneficial for many surgical patients.

"We expect that this new agent will be safer than all currently available general anesthetics for use in the operating room, emergency room, intensive care units and other places where anesthesia may be required," said Dr. Raines.

Despite the fact that general anesthetics are administered approximately 30 million times per year and are some of the most beneficial drugs used in medicine, they remain potentially dangerous because nearly all of them can have negative effects on critical functions such as breathing and blood pressure.

According to Dr. Raines, MOC-etomidate is a "soft analogue" of etomidate, meaning that it is a derivative of a parent drug specifically designed to undergo fast and predictable metabolism after its beneficial effects have taken place in the body.

Etomidate is an intravenous general anesthetic used to induce anesthesia at the start of surgery. It is distinguished from other anesthetics in that it has minimal effects on breathing and cardiovascular function.

But etomidate cannot be used to maintain anesthesia during surgery because it produces very prolonged and potentially dangerous suppression of the body's adrenal glands, said Dr. Raines.

MOC-etomidate, on the other hand, was shown in laboratory and animal studies to act upon the body for only a very short time period, to be quickly metabolized, and to provide faster recovery from anesthesia, all while producing no significant effects on the adrenal glands within minutes after administration.

To obtain their results, the research group utilized tadpoles and rats (to determine necessary drug concentrations and the effects of those drugs), and human liver cells (to assess how quickly the drug would be metabolized in the body).

MOC-etomidate could be especially beneficial for those most vulnerable to the side effects of many general anesthetics. The development of this new rapidly metabolized etomidate-like drug may permit more widespread use of MOC-edomidate compared to etomidate.

"Along with affecting breathing and cardiovascular function, general anesthetics also have other undesirable side effects, such as sedation and nausea, that linger long after their anesthetic actions have worn off," said Dr. Raines. "These side effects are particularly worrisome in the elderly and critically ill."

Dr. Raines plans additional studies with MOC-etomidate as well as other novel anesthetic etomidate analogues that his group has developed. "We have some more work to do in the laboratory and hope to identify pharmaceutical industry partners that can help us advance these new anesthetics to clinical use," said Dr. Raines.

Anesthesiologists: Physicians providing the lifeline of modern medicine. Founded in 1905, the American Society of Anesthesiologists is an educational, research and scientific association with 43,000 members organized to raise and maintain the standards of the medical practice of anesthesiology and improve the care of the patient.

For more information visit the ASA Web site at www.asahq.org.