title: Post-ECT agitation and plasma lactate concentrations.
abstract: This prospective study evaluated the hypothesis that emergence agitation after electroconvulsive therapy (ECT) could be caused by lactate-induced panic secondary to insufficient neuromuscular blockade. Plasma lactate levels were measured before and after 245 consecutive ECT sessions in 37 patients monitored for evidence of post-ECT agitation. ECT was administered using a brief-pulse, rectangular, constant-current device through bilaterally placed electrodes under general anesthesia and neuromuscular blockade. Agitation was observed in 7% of all ECT sessions. No significant difference could be found in pre-ECT lactate levels. However, mean post-ECT lactate levels in agitated sessions were significantly greater than those in nonagitated sessions (4.77 versus 2.54 mmol/l, p < 0.05). An increase (+27%) in the pre-ECT succinylcholine dose for those patients who previously had repeated post-ECT agitation resulted in cessation of post-ECT agitation and return of the formerly high post-ECT lactate levels to normal (1.61 versus 2.07 mmol/l). Although the number of patients who had post-ECT agitation was small, the data support the hypothesis that post-ECT agitation might be a manifestation of lactate-induced panic.
authors.affiliation: Laboratoire de Psychiatrie, Université Victor Segalen Bordeaux 2, INSERM-IFR 8 et CNRS-FR 13, France. marc.auriacombe@labopsy.u-bordeaux2.fr
authors.forename: M
authors.initials: M
authors.lastname: Auriacombe
authors.forename: J P
authors.initials: JP
authors.lastname: Rénéric
authors.forename: D
authors.initials: D
authors.lastname: Usandizaga
authors.forename: F
authors.initials: F
authors.lastname: Gomez
authors.forename: I
authors.initials: I
authors.lastname: Combourieu
authors.forename: J
authors.initials: J
authors.lastname: Tignol
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000758:Anesthesia; D018686:Anesthetics, Intravenous; D004565:Electroconvulsive Therapy / Q000009:adverse effects*; D005260:Female; D006801:Humans; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D008723:Methohexital; D008875:Middle Aged; D009467:Neuromuscular Depolarizing Agents; D016584:Panic Disorder / Q000209:etiology / Q000523:psychology; D011595:Psychomotor Agitation / Q000209:etiology* / Q000523:psychology; D013390:Succinylcholine
chemical_list: D018686:Anesthetics, Intravenous; D009467:Neuromuscular Depolarizing Agents; D019344:Lactic Acid; D008723:Methohexital; D013390:Succinylcholine