Staffing and Location of ECT Treatments
The safe and effective provision of ECT requires a highly trained and experienced staff that includes a psychiatrist, a provider of anesthesia, and, generally, at least one nurse. The anesthesia provider, usually an anesthesiologist or a nurse anesthetist, should be able to maintain an airway, deliver brief general anesthesia, and handle any foreseeable medical emergencies that might occur in the treatment or recovery areas (American Psychiatric Association Committee on ECT 2000). In this regard, the lack of capability for on-site acute management of such emergencies necessitates the transfer of patients who are medically at high risk to a facility with this capacity to receive their ECT. In terms of space requirements, separate treatment and recovery areas should be provided, whenever possible.
Although ECT traditionally has been an inpatient treatment, except for continuation/maintenance use, recent constraints on clinical practice have led to a growing pressure to provide part, if not all, of ECT courses on an outpatient basis. Conditions for outpatient ECT that should be met include the following: 1) the patient does not otherwise need to be hospitalized; 2) foreseeable risks are detectable and manageable under these circumstances; 3) the patient, with the assistance of significant others, is capable of complying with the management plan; and 4) an attending psychiatrist is available to maintain overall responsibility for the case (American Psychiatric Association Committee on ECT 2000; Fink et al. 1996). From a personnel and space perspective, outpatient ECT requires that the patient be briefly evaluated before each treatment and that the patient not be discharged from the facility until he or she is capable of leaving with the assistance of a significant other.
Number of Treatments
The number of ECT treatments administered in an index course should be based on clinical progress, with the goal being the achievement of a maximum therapeutic response (see “Continuation/Maintenance ECT” section in this chapter for a discussion of treatment number and frequency with each modality). Typically, this requires 6-12 treatments, although as few as 3 or as many as 20 or more may be required. As noted earlier, reconsent should be considered in cases when an unusually long index ECT course is required (American Psychiatric Association Committee on ECT 2000). In general, there does not appear to be any benefit in continuing ECT past the point when a therapeutic plateau (i.e., no further improvement) has been reached. There is no “lifetime maximum” number of treatments.
Frequency of Treatments
In the United States, the usual frequency of administration for ECT is three times a week, as opposed to two times a week in some other countries (American Psychiatric Association Committee on ECT 2000). Some recent studies indicate that administration of twice-weekly bilateral ECT treatments appears to result in the same degree of therapeutic response as three treatments per week but may be associated with fewer short-term cognitive side effects and a slower rate of response (Shapira et al. 1998). Specific situations do exist in which adjustments in treatment rate are clinically indicated. For example, patients with an urgent need for a rapid response may be treated on a daily basis for the first few treatments, whereas patients who develop delirium or severe cognitive deficits during the treatment course may require their treatment frequency to be decreased to two or even one session per week.
Multiple Monitored ECT
Multiple monitored ECT (MMECT) involves induction of multiple seizures (from 2 to more than 10) performed during a single treatment session (Maletzky 1981). The efficacy and safety of this technique have been controversial, and there have been reports of adverse effects such as increased cognitive deficits, prolonged seizures, and exaggerated cardiovascular response (Abrams 1997a). Roemer et al. (1990) reported the results of a controlled trial involving 29 patients that compared induction of two bilateral ECT seizures per session with the standard procedure of one seizure per session. Although they found that MMECT was associated with a more rapid response, these investigators also observed more substantial cognitive deficits with this technique. At present, MMECT should be avoided except for the induction of two seizures per session in situations of great urgency (American Psychiatric Association Committee on ECT 2000).
Anticholinergic agents, typically either atropine or glycopyrrolate, have traditionally been used both to minimize oropharyngeal secretions and to minimize the risk of parasympathetically mediated poststimulus asystole or postictal bradycardia. Glycopyrrolate, generally given in a dose of 0.2-0.3 mg intramuscularly or subcutaneously 30 minutes before the treatment, or intravenously 2 minutes before anesthesia, is now preferred by many practitioners because it is less likely to cross the blood-brain barrier and have a cerebral effect. Recently, the entire issue of routine anticholinergic premedication has come into question, although its use is clearly indicated in patients for whom the parasympathetic effects of ECT should be avoided (American Psychiatric Association Committee on ECT 2000).
The marked, but transient, surge in systolic pressure and heart rate that typically occurs soon after seizure onset is of concern in patients at risk for cardiac ischemia. The attenuation of such effects, using sympatholytic agents such as labetalol, is desirable in such cases, but the practitioner should take care to avoid inducing a hypotensive state during the recovery period. Although esmolol is shorter-acting than labetalol, it is also more likely to shorten seizure duration and should generally be reserved for use in the postictal period to control either sustained hypertension or the sympathetic arousal that may sometimes be associated with awakening. Alternatives to sympatholytic agents in the prevention and management of peri-ictal hypertension include nitroglycerine and nifedipine.
The adequacy of the airway should be ensured before infusion of muscle relaxant. Patients should receive 100% oxygen by mask using positive-pressure ventilation at a respiratory rate of approximately 15 per minute. Ventilation should begin before infusion of the anesthetic agent and should continue until resumption of spontaneous breathing (American Psychiatric Association Committee on ECT 2000). A soft mouthguard should be used to protect the teeth, lips, and soft tissue of the oral cavity from the involuntary muscle contractions that accompany the electrical stimulus.
A light level of anesthesia is used to provide amnesia for the effects of the muscular paralysis and the electrical stimulus. The primary agent currently used in the United States is methohexital, a rapidly acting barbiturate with a short half-life (American Psychiatric Association Committee on ECT 2000; Swartz 1993). Typical doses range from 0.75 to 1.0 mg/kg. The dose should be kept to the minimum necessary because of this drug’s anticonvulsant effects. The nonbarbiturate agent propofol has been avoided by many practitioners because of its tendency to significantly shorten seizures (Swartz 1992), although randomized trials have not shown that this effect is associated with diminished efficacy (Martensson et al. 1994). Ketamine, which does not raise seizure threshold, is an alternative anesthetic agent for patients with very high seizure thresholds (Rasmussen et al. 1996).
Because of its rapid action and extremely short half-life, succinylcholine is the muscle relaxant routinely used for ECT. The typical routine dose is 0.75-1.00 mg/kg, with higher doses used for patients needing more complete relaxation. Alternative agents, used in patients with inborn or acquired pseudocholinesterase deficiency, severe neuromuscular rigidity, extensive burns, or hyperkalemia, include curare, atracurium, mivacurium, rocuronium, and rapacuronium (each of which is associated with a longer period of apnea, even when reversed with physostigmine).
Current anesthetic practice includes monitoring of respiration, blood oxygen saturation (via oximetry), blood pressure, and heart rate from before anesthesia induction up to the time the patient leaves the treatment room. Physiological monitoring in the recovery area has approached this level of intensity in recent years.
Revision date: June 14, 2011
Last revised: by David A. Scott, M.D.