For ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS), when surgery is not feasible, or in cases of severe biochemical disturbances, immunosuppression or mental instability, medical therapy with agents such as etomidate is indicated. We present our experience in using etomidate for a 41-year old female with EAS secondary to a malignant mediastinal paraganglioma. We were able to demonstrate that etomidate can be used effectively to control severe hypercortisolism in a lower dose than previously described.
Etomidate ; ACTH Syndrome, Ectopic

BACKGROUND: Etomidate frequently causes myoclonus. Since the myoclonus is caused by a transient disequilibrium due to etomidate exposure in the CNS, we hypothesized that a slow rate of injection of the drug may decrease the incidence of myoclonus. We conducted a prospective randomized study to compare the effect of two different types of the etomidate injection rate on the incidence and severity of myoclonus. METHODS: Fifty patients were randomly assigned to the fast-injection group (group F) or slow-injection group (group S): Group F patients received etomidate (0.3 mg/kg) over ten seconds. The same dose was administered over two minutes for group S patients. The response to the injection of etomidate was graded on a four-point scale in a blinded manner. The time to loss of consciousness (LOC) was also recorded. RESULTS: The incidence of myoclonus was significantly lower (P < 0.001) in group S patients; 84% and 28% in group F and group S patients, respectively. The myoclonus was also significantly less severe in group S patients (P < 0.001). The time to LOC was significantly longer in group S patients (106 +/- 22 sec) than that of group F patients (49 +/- 18 sec, P < 0.001). CONCLUSIONS: With same dose, a slower rate of injection resulted in a lower incidence of myoclonus and can effectively reduce myoclonus without the use of a pretreatment agent.
Etomidate ; Humans ; Incidence ; Myoclonus ; Prospective Studies ; Unconsciousness

BACKGROUND: Etomidate injection is often associated with myoclonus. Etomidate injection technique influences the incidence of myoclonus. This study was designed to clarify which of the two injection techniques—slow injection or priming with etomidate—is more effective in reducing myoclonus. METHODS: This prospective randomized controlled study was conducted on 189 surgical patients allocated to three study groups. Control group (Group C, n = 63) received 0.3 mg/kg etomidate (induction dose) over 20 s. Priming group (Group P, n = 63) received pretreatment with 0.03 mg/kg etomidate, followed after 1 min by an etomidate induction dose over 20 s. Slow injection group (Group S, n = 63) received etomidate (2 mg/ml) induction dose over 2 min. The patients were observed for occurrence and severity of myoclonus for 3 min from the start of injection of the induction dose. RESULTS: The incidence of myoclonus in Group P (38/63 [60.3%], 95% CI: 48.0–71.5) was significantly lower than in Group C (53/63 [84.1%], 95% CI: 72.9–91.3, P = 0.003) and Group S (49/63 [77.8%], 95% CI: 66.0–86.4, P = 0.034). Myoclonus of moderate or severe grade occurred in significantly more patients in Group C (68.3%) than in Group P (36.5%, P < 0.001) and Group S (50.8%, P = 0.046), but the difference between Groups P and S was not significant (P = 0.106). CONCLUSIONS: Priming is more effective than slow injection in reducing the incidence of myoclonus, but their effects on the severity of myoclonus are comparable.
Etomidate ; Humans ; Incidence ; Myoclonus* ; Prospective Studies

For ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS), when surgery is not feasible, or in cases of severe biochemical disturbances, immunosuppression or mental instability, medical therapy with agents such as etomidate is indicated. We present our experience in using etomidate for a 41-year old female with EAS secondary to a malignant mediastinal paraganglioma. We were able to demonstrate that etomidate can be used effectively to control severe hypercortisolism in a lower dose than previously described.
Etomidate ; ACTH Syndrome, Ectopic ; Cushing Syndrome

BACKGROUND: Etomidate is a rapid-acting sedative/hypnotic agent with little or no cardiovascular effect and a high therapeutic index. For this reason, etomidate has been used as an anesthetic induction and maintenance agent in patients with poor cardiovascular reserve. Bispectral index (BIS), a parameter derived from electroencephalography (EEG), has been proposed as a measure of anesthetic effect and is shown to correlate with increasing sedation and loss of consciousness. To establish its utility for this purpose, it is important to determine the correlation among BIS, measured drug concentration, and increasing levels of sedation. This study was designed to evaluate this relation for etomidate. METHODS: Eighteen adult patients scheduled for elective surgery, ASA physical status I or II, were included. Etomidate was administerd until loss of consciousness (loss of verbal contact) using syringe pump with a constant rate (150 ml/h) and patients were observed until regaining consciousness as decided by prompt verbal response on command of "open your eyes". A BIS was monitored, arterial blood samples were obtained for analysis of drug concentration, and the patients were evaluated for level of sedation by the responsiveness portion of the modified observer's assessment of alertness/sedation (OAA/S) scale. RESULTS: The BIS (r = 0.86) correlated significantly with the OAA/S more than the etomidate plasma concentration (r = 0.57). The BIS values, OAA/S, and blood concentrations were 50, 1.26, and 1337 ng/ml at induction and 75, 4.6, and 236 ng/ml at awakening, respectively. CONCLUSIONS: We concluded that the BIS accurately predicted level of sedation with etomidate during anesthesia induction, but the correlation between blood concentration and level of sedation was less strong.
Adult ; Anesthesia* ; Anesthetics ; Consciousness ; Electroencephalography ; Etomidate* ; Humans ; Plasma ; Syringes ; Unconsciousness

BACKGROUND: Etomidate frequently induces myoclonus when administered intravenously with bolus injection during anesthetic induction. This can be bothersome for the anesthesiologist. The dose of remifentanil appropriate for preventing myoclonus without side effects was investigated. METHODS: All patients with American Society of Anesthesiologists (ASA) physical status I-III were divided into three groups (n = 33 per group) according to the pretreatment effect site concentration of remifentanil (Ultiva, Glaxo-Wellcome, Munchen, Germany) of 0, 2 or 4 ng/ml (Group N: 0 ng/ml, Group R: 2 ng/ml, Group Q: 4 ng/ml) by a target controlled infusion (TCI) system. After a 0.3 mg/kg dose of etomidate was injected intravenously for over 1 minute for anesthetic induction, myoclonus was observed. Before the etomidate injection, the patients were pretreated with remifentanil and their side effects were monitored. RESULTS: The number of patients showing myoclonus was significantly different among the groups. The incidence of myoclonus was 81%, 12% and 0% (groups N, R, and Q, respectively, P < 0.01). Side effects including bradycardia and hypotension did not occur in either Group R or Q. Chest wall rigidity occured in 45% of patients in Group Q. CONCLUSIONS: Administration with a 2 ng/ml effect site concentration of remifentanil could reduce the incidence of myoclonus caused by etomidate bolus injection without chest wall rigidity.
Bradycardia ; Etomidate ; Humans ; Hypotension ; Incidence ; Myoclonus ; Piperidines ; Thoracic Wall

BACKGROUND: The hypothesis that subcortical disinhibition is the reason for etomidate-induced myoclonus suggest that drugs acting on the subcortical area may reduce myoclonus. To verify the hypothesis, premedication with placebo, etomidate of a small dosage, midazolam and fentanyl were compared. METHODS: Sixty ASA physical status I or II patients undergoing elective surgery were allocated into four groups. All groups were induced with etomidate 0.3 mg/kg and vercuronium 0.1 mg/kg and maintained with 50% N2O and 1.5-2% enflurane. Group I (n = 15) received normal saline 3 ml 5 minutes before the etomidate 0.3 mg/kg administration, group II (n = 15) received 0.05 mg/kg etomidate 50 seconds before the etomidate 0.3 mg/kg administration, group III received midazolam 0.05 mg/kg 5 minutes before the etomidate 0.3 mg/kg and group IV received 2 microgram/kg fentanyl 5 minutes before the etomidate 0.3 mg/kg. In all patients, the grade, starting time, maintenance time of myoclonus and vital signs were checked and compared between the four groups. RESULTS: In group IV, myoclonus did not develope except in one patient and there were no differences in the incidence of myoclonus between the others. All premedicating drugs do not affect vital signs. CONCLUSIONS: We find that fentanyl reduces the incidence of etomidate-induced myoclonus but midazolam and a small dose of etomidate are not effective.
Anesthesia* ; Enflurane ; Etomidate* ; Fentanyl* ; Humans ; Incidence ; Midazolam* ; Myoclonus* ; Premedication ; Vital Signs

BACKGROUND: Cardiovascular instability after induction of intravenous anesthetics may be explained partly by direct negative inotropic effects. We studied the effects of etomidate and propofol on the inward calcium currents (ICa) of rat ventricular myocytes using the whole-cell voltage-clamp technique. METHODS: ICa was elicited by progressively depolarizing cells from -40 to -50 mV. The peak amplitude of ICa was measured before, during and after the administration of equimolar concentrations of etomidate and propofol. RESULTS: Exposure to etomidate and propofol produced a concentration-dependent inhibition of ICa.; 1, 10, 100 and 300 micrometer of etomidate decreased the peak ICa (mean +/- SEM) by 14.5 +/- 6.3, 25.9 +/- 9.4, 31.9 +/- 12.1, 42.5 +/- 8.8% and 1, 10, 100 and 300 micrometer of propofol decreased the peak ICa by 15.7 +/-3.4, 21.3 +/-2.5, 59.2 +/-2.0, 69.9 +/-2.8%, respectively. COCLUSIONS: These results suggest that etomidate and propofol have a direct negative inotropic effect via inhibition of inward calcium currents in rat ventricular myocytes.
Anesthetics, Intravenous ; Animals ; Calcium* ; Etomidate* ; Muscle Cells* ; Patch-Clamp Techniques ; Propofol* ; Rats*

BACKGROUND: The clinical efficacy of electroconvulsive therapy (ECT) primarily depends on the adequacy of the seizure duration, but the intravenous anesthetics which are commonly used for ECT may possess anticonvulsant properties and shorten the seizure duration. The aim of this study was to compare the effects of propofol and etomidate on seizure duration and hemodynamic responses during ECT. METHODS: 30 patients undergoing maintenance ECTs were evaluated and divided into two groups randomly. Hypnosis was induced with a bolus injection of either 1.5 mg/kg of propofol or 0.3 mg/kg of etomidate in each group. Time to unconsciousness, seizure duration, heart rate, mean arterial pressure and recovery time were measured after delivery of electrical stimulus. The dynamic energy (joules) delivered was recorded. Correlation between seizure duration and recovery time was calculated and the rates of seizure induction failure after first electrical stimulus were compared. RESULTS: The seizure duration was shorter in the propofol group (34.0 +/- 3.8 s) than in the etomidate group (50.0 +/- 4.0 s)(P < 0.01). The heart rate was significantly lower in the propofol group (132.1 +/- 3.8, 99.7 +/- 6.2 bpm) than in the etomidate group (146.0 +/- 4.2, 119.8 +/- 7.5 bpm) at the time of ECT and 1 min after ECT respectively (P < 0.05). The mean arterial pressure was significantly lower in the propofol group than in the etomidate group from the time of ECT to 10 min after ECT (P < 0.05). CONCLUSIONS: Propofol showed excellent hemodynamic stability and was a good hypnotic for ECT therapy, but etomidate might be a useful alternative to propofol in patients who have an inadequate seizure duration.
Anesthetics, Intravenous ; Arterial Pressure ; Electroconvulsive Therapy ; Etomidate* ; Heart Rate ; Hemodynamics* ; Humans ; Hypnosis ; Propofol* ; Seizures* ; Unconsciousness

BACKGROUND: Etomidate, an anesthetic induction agent, has dose-dependent involuntary myoclonic movement. This prospective, randomized study was conducted to determine the safety of etomidate in patients with major burn injury. METHODS: Twenty ASA physical status II or III adult patients, scheduled for an elective early escharectomy, were studied. These patients had varying degrees of myoclonic activity at the time of anesthesia induction with etomidate (0.3 mg/kg). The plasma concentrations of potassium before and after myoclonus were measured and compared. RESULTS: Incidence of myoclonus after the injection of etomidate induction dose was 31.7%. No significant changes in plasma concentrations of the potassium level before or after myoclonus were found in this study group. CONCLUSIONS: Myoclonus during induction of anesthesia with etomidate did not cause any change in the plasma concentration of potassium. It appears to be a safe anesthetic induction agent in patients with major burns, threatened by hemodynamic and pulmonary insufficiency.
Adult ; Anesthesia* ; Burns* ; Etomidate* ; Hemodynamics ; Humans ; Incidence ; Myoclonus ; Plasma* ; Potassium* ; Prospective Studies