Etomidate

Etomidate (USAN, INN, BAN) (marketed as Amidate) is a short-acting intravenous anaesthetic agent used for the induction of general anaesthesia and sedation for short procedures such as reduction of dislocated joints, tracheal intubation, and cardioversion. It was developed at Janssen Pharmaceutica in 1964 and was introduced as an intravenous agent in 1972 in Europe and in 1983 in the United States. Etomidate (USAN, INN, BAN) (marketed as Amidate) is a short-acting intravenous anaesthetic agent used for the induction of general anaesthesia and sedation for short procedures such as reduction of dislocated joints, tracheal intubation, and cardioversion. It was developed at Janssen Pharmaceutica in 1964 and was introduced as an intravenous agent in 1972 in Europe and in 1983 in the United States. In emergency settings, etomidate was one of the most frequently used sedative hypnotic agents, however propofol is now usually the drug of choice due to its significantly better properties. It is used for conscious sedation and as a part of a rapid sequence induction to induce anaesthesia. It is used as an anaesthetic agent since it has a rapid onset of action and a safe cardiovascular risk profile, and therefore is less likely to cause a significant drop in blood pressure than other induction agents. In addition, etomidate is often used because of its easy dosing profile, limited suppression of ventilation, lack of histamine liberation and protection from myocardial and cerebral ischemia. Thus, etomidate is a good induction agent for people who are hemodynamically unstable. Etomidate also has interesting characteristics for people with traumatic brain injury because it is one of the only anesthetic agents able to decrease intracranial pressure and maintain a normal arterial pressure. In those with sepsis, one dose of the medication does not appear to affect the risk of death. Another use for etomidate is to determine speech lateralization in people prior to performing lobectomies to remove epileptogenic centres in the brain. This is called the etomidate speech and memory test, or eSAM, and is used at the Montreal Neurological Institute. However, only retrospective cohort studies support the use and safety of etomidate for this test. In addition to its action and use as an anesthetic, etomidate has also been found to directly inhibit the enzymatic biosynthesis of steroid hormones, including corticosteroids in the adrenal gland. As the only adrenal steroidogenesis inhibitor available for intravenous or parenteral administration, it is useful in situations in which rapid control of hypercortisolism is necessary or in which oral administration is unfeasible. The U.S. state of Florida used the drug in a death penalty procedure when Mark James Asay, 53, was executed on August 24, 2017. He became the first person in the U.S. to be executed with etomidate as one of the drugs. Etomidate replaces midazolam as the sedative. Drug companies have made it harder to buy midazolam for executions. The etomidate was followed by rocuronium bromide, a paralytic, and finally, potassium acetate in place of the commonly used potassium chloride injection to stop the heart. Potassium acetate was first used for this purpose inadvertently in a 2015 execution in Oklahoma. Etomidate suppresses corticosteroid synthesis in the adrenal cortex by reversibly inhibiting 11β-hydroxylase, an enzyme important in adrenal steroid production; it leads to primary adrenal suppression. Using a continuous etomidate infusion for sedation of critically ill trauma patients in intensive care units has been associated with increased mortality due to adrenal suppression. Continuous intravenous administration of etomidate leads to adrenocortical dysfunction. The mortality of patients exposed to a continuous infusion of etomidate for more than 5 days increased from 25% to 44%, mainly due to infectious causes such as pneumonia. Because of etomidate-induced adrenal suppression, its use for patients with sepsis is controversial. Cortisol levels have been reported to be suppressed up to 72 hours after a single bolus of etomidate in this population at risk for adrenal insufficiency. For this reason, many authors have suggested that etomidate should never be used for critically ill patients with septic shock because it could increase mortality. However, other authors continue to defend etomidate's use for septic patients because of etomidate's safe hemodynamic profile and lack of clear evidence of harm. A study by Jabre et al. showed that a single dose of etomidate used for Rapid Sequence Induction prior to endrotracheal intubation has no effect on mortality compared to ketamine even though etomidate did cause transient adrenal suppression. In addition, a recent meta-analysis done by Hohl could not conclude that etomidate increased mortality. The authors of this meta-analysis concluded more studies were needed because of lack of statistical power to conclude definitively about the effect of etomidate on mortality. Thus, Hohl suggests a burden to prove etomidate is safe for use in septic patients, and more research is needed before it is used. Other authors advise giving a prophylactic dose of steroids (e.g. hydrocortisone) if etomidate is used, but only one small prospective controlled study in patients undergoing colorectal surgery has verified the safety of giving stress dose corticosteroids to all patients receiving etomidate. In a retrospective review of almost 32,000 people, etomidate, when used for the induction of anaesthesia, was associated 2.5-fold increase in the risk of dying compared with those given propofol. People given etomidate also had significantly greater odds of having cardiovascular morbidity and significantly longer hospital stay. These results, especially given the large size of study, strongly suggest that, at the very least, clinicians should use etomidate judiciously.