New Anesthesia May Be Safer for Critically Ill

THURSDAY, July 23 (HealthDay News) -- A new variation of a common general anesthesia has been developed that may be safer for some patients.

Preclinical studies done on rats put under with MOC-etomidate, a chemically altered version of the anesthetic etomidate, found the drug does not cause blood pressure to drop suddenly or slow adrenal gland activity, common side effects that can be fatal to the elderly or certain critically ill patients.

"We have shown that making a version of etomidate that is broken down very quickly in the body reduces the duration of adrenal suppression while retaining etomidates benefit of keeping blood pressure much more stable than other anesthetics do," study leader Dr. Douglas Raines, of Massachusetts General Hospital's department of anesthesia, critical care and pain medicine, said in a hospital news release.

Most general anesthetics cause blood pressure to fall, often quickly. In cases where this could endanger the patient, doctors typically use etomidate with other agents to help keep the person under, a method that requires intense monitoring of blood pressure to avoid critical drops. Etomidate also suppresses the adrenal glands, an effect that can last for up to several days.

According to the August issue of Anesthesiology, the research team added a molecule to the chemical structure of etomidate that causes it to break down naturally. This same process is often used to create "soft analogue" drugs -- ones that quickly metabolize.

"If all goes well, we expect that we could give a large dose of MOC-etomidate to induce anesthesia and then run a continuous infusion to maintain anesthesia without reducing blood pressure in even very sick patients," said Raines, who is also an associate professor of anesthesia at Harvard Medical School in Boston. "We also anticipate that patients will wake more quickly and with less sedation after surgery and anesthesia."

The researchers next plan to study how continuous infusion of MOC-etomidate affects animals.

More information

The American Society of Anesthesiologists has more about anesthesia.