Can the laryngeal mask play a role in electroconvulsive treatment? A pilot study

Introduction: Optimising ventilation control in the anaesthetic process of electroconvulsive therapy (ECT) can be a method for improving the effectiveness and safety of some treatments. There are several approaches for inducing adequate therapeutic seizures in patients with medical co-morbidity or in those with high seizure thresholds, although all of them present limitations. A new approach is hyperventilation with laryngeal mask, a method that improves oxygenation, achieves hypocapnia, and lowers seizure threshold. Thus, hyperventilation with laryngeal mask could, hypothetically, be useful to decrease the energy needed to obtain adequate therapeutic seizures.

Material and methods: A randomized crossover study was conducted on 14 patients on maintenance ECT, using a laryngeal mask versus a facemask. When laryngeal masks were applied, the energy was reduced by 45% compared with the energy required when ventilated with facemasks (performed with standard dose).

Results: The results of the study revealed that, despite a 45% energy reduction with laryngeal mask, there were no significant differences in seizure length in either group.

Conclusions: These results prompt us to propose ventilation with laryngeal mask as an alternative to decrease energy applied without lowering seizure times. This is a preliminary study with a small sample, which opens new lines of research. Larger samples and other measurements of seizure adequacy are needed in future studies, in order to study possible improvements in ventilation and minimising adverse effects of ECT, especially in patients with medical co-morbidities.