Cortisol Level After Repeated Doses of Etomidate

The aim of this study is to investigate the effect of repeated doses of etomidate on the adrenocortical synthesis of corticosteroids in patients scheduled to electroconvulsive therapy under general anesthesia

Patients aged 18 to 65, ASA status I to III and scheduled to electroconvulsive therapy under general anesthesia every 2 days for 3 to 4 weeks, are included in this prospective observational study. Patients with previously documented adrenocortical insufficiency or under corticosteroid medication are not included Anesthesia protocol is standardized with 0.5 mg/kg propofol, 0.3 mg/kg etomidate and 0.5 mg/kg succinylcholine. Induction of anesthesia is performed after 3 minutes of preoxygenation with 6 l/min fresh gas flow with 100% inspired fraction of oxygen. The patients are maintained in facial mask ventilation until recovery. During the procedure heart rate, non-invasive blood pressure, pulsed oximetry and end tidal carbon dioxyde are monitored.

Blood samples for cortisol dosage are performed immediately before the first session (baseline cortisol = C0), 24 hours after the first session (cortisol after a single dose of etomidate = C1), 24 hours after the third session (cortisol after 3 doses of etomidate = C3) and 24 hours after the sixth session (cortisol after six doses of etomidate = C6). All blood samples are performed at 9 and collected in normal tube.

Blood samples were centrifuged (4000 tours during 10 minutes) and congealed at -20°. All congealed samples were analyzed at the end of the recruitment, using the Electrochimiluminescence ECLIA -Cobas - Roche. The normal value are between6.2-19.4 µg/dL . Sample analysis was performed by a biochemist blinded to clinical detail.

For every end point time, heart rate and blood pressure are noted. Blood samples for glycaemia, sodium, potassium and bicarbonates are performed at the same rate.

End point criteria and statistical analysis:

Delta-1-cortisol is defined as the difference between C0 and C1 Delta-3-cortisol is defined as the difference between C0 and C3 Delta-6-cortisol is defined as the difference between C0 and C6 We planned to enroll 30 patients during the twelve months.

Wilcoxon test for depended data will be used to compare:

Inclusion criteria

• Patients aged 18 to 65,
• ASA status I to III
• and scheduled to electroconvulsive therapy under general anesthesia every 2 days for 3 to 4 weeks

Exclusion criteria

• previously documented adrenocortical insufficiency
• or under corticosteroid medication