COMPARATIVE EFFECTS OF ESMOLOL AND LABETALOL TO ATTENUATE HYPERDYNAMIC STATES AFTER ELECTROCONVULSIVE-THERAPY

We studied 18 patients (age range, 53-90 yr) with at least one cardiov ascular risk factor who were treated with electroconvulsive therapy (E CT) and compared effects of five pretreatments: no drug; esmolol, 1.3 or 4.4 mg/kg; or labetalol, 0.13 or 0.44 mg/kg. Each patient received all five treatments, during a series of five ECT sessions. Pretreatmen t was administered as a bolus within 10 s of induction or anesthesia. Doses of methohexital and succinylcholine were constant for the series of treatments and the assignment to no drug or to drug and dose was d etermined by randomized block design. Measurements of systolic and dia stolic blood pressure SBP, DBP) and heart rate (HR) were recorded duri ng the awake state and 1, 3, 5, and 10 min after the seizure. The devi ation of ST segments from baseline was measured by an electrocardiogra m (ECG) monitor equipped with ST-segment analysis software. The result s (mean +/- SBM) show that without pretreatment, there were significan t (P < 0.05) peak increases in SEP and HR (55 +/- 5 mm Hg and 37 +/- 6 bpm, respectively), recorded 1 min after the seizure. Comparable redu ctions (by approximately 50%) in these peak values were achieved after esmolol (1.3 mg/kg) or labetalol (0.13 mg/kg), and cardiovascular res ponses were nearly eliminated after the same drugs in doses of 4.4 and 0.44 mg/kg respectively. The deviation of ST-segment values from base line in any lead was not measurably influenced by either antihypertens ive drug. SEP values were lower after labetalol 10 min after the seizu re, but not after esmolol. Asystolic time after the seizure was not si gnificantly longer with either drug. No adverse reactions were observe d. Because SEP effects were still present 10 min after the seizure, es molol may be preferred if administration of a large dose of a beta-adr energic blocker is contemplated.