Modern anesthesia technique during ECT includes careful management of the patient’s airway with the administration of 100% supplemental oxygen.16 Once general anesthesia has been induced, hyperventilation is performed using a bag and mask device during the 1 to 2 minutes before the initiation of therapy. Hyperventilation decreases the blood levels of carbon dioxide, reduces the seizure threshold, and increases seizure duration. Ventilation with 100% oxygen during this period also increases the amount of oxygen available to the brain for use during the treatment.
The anesthesiologist who manages the airway during this period is careful to protect the patient from aspiration while maintaining ventilation and oxygenation. Sometimes a soft preshaped airway device (oral airway) is placed to facilitate this. In most patients, return of spontaneous respiration occurs within 3 to 5 minutes after induction, before the effects of the anesthetic have worn off and the patient is awake. Some patients may begin breathing immediately after the seizure ceases. For others, ventilatory support is continued until the patient takes adequate breaths on his own and no longer requires assistance.
Management of hypertension
The increase in heart rate and blood pressure that typically accompany an ECT-induced seizure are easily managed with currently available short-acting intravenous medications.17 The stimulus applied to the brain during the initiation of ECT results in a profound parasympathetic surge. Asystole during this period is common but temporary, even though it may persist throughout the stimulus application.
Following stimulus termination, the resulting seizure is accompanied by a profound sympathetic surge, typically associated with tachycardia and hypertension. The elevations in heart rate and blood pressure can be significant, with increases in systolic blood pressure by as much as 40% over baseline.10 Safe control of heart rate and blood pressure can easily be achieved with frequent dosing of a short-acting agent such as esmolol(Drug information on esmolol), labetalol(Drug information on labetalol), or nitroglycerin.
Modern anesthesia techniques allow ECT to be performed with a high degree of patient safety and comfort. Simple, standardized protocols ensure that it can be provided in many facilities with consistent antidepressant results and a favorable adverse-effect profile. Mental health practitioners should be knowledgeable about the basics of the procedure, including how the anesthetic is given, in order to provide accurate information for patients who may be candidates for ECT.
While only a small percentage of practitioners will actually provide ECT, many more will encounter seriously ill patients who will need to be referred to facilities in which ECT is performed. For those practitioners, we hope that this summary is helpful; for those readers who want to learn more, authoritative resources include the American Psychiatric Association’s Task Force Report on ECT as well as several excellent text books and online resources.1,10,18