Mohammed T. Abou-Saleh

ELECTROCONVULSIVE THERAPY 435interest in stimulus intensity, seizure threshold and seizureduration. It is clear that seizure threshold will increase by about40% during the course of ECT and the seizure duration will tendto decrease by about one-third. However, while it seems thatoutcome is not correlated with either seizure duration or thresholdfor bilateral ECT 35 , it may be more important to keep the stimulusintensity above seizure threshold in unilateral treatment 36 . Seizureduration is more difficult to evaluate, as some patients regularlyhave brisk and brief responses with good results. The use ofpropofol to induce anaesthesia consistently reduces seizureduration, although apparently without affecting efficacy 37,38 . Theuse of caffeine prior to treatment to prolong seizure activity hasbeen associated with improved efficacy in some patients 39 . Itwould seem that, as a rule of thumb, we should aim for a seizurelength of around 25 s and any seizure less than 15 s or more than120 s is likely to adversely affect response 40 . Cumulative seizureduration again seems less interesting now than it once was as ameasure of the length of a course of treatment, and clinicalresponse still seems the best measure.There is no evidence that routine atropine premedicationimproves cardiac stability or lessens secretions. Theoretically itcould cause confusion, but there is no convincing evidence of thiseither. Glycopyrrolate, which does not cross the blood–brainbarrier, may be a better drug to use as a drying agent.Methohexitone for the induction of anaesthesia at a dosage of30–50 mg is adequate to ensure sleep without hangover, andmuscle relaxation with a suxamethonium dosage of 20–40 mg isenough to modify the convulsion without abolishing all evidenceof motor activity. If the minimum amount of anaesthetic iscombined with treatment early in the morning, the patient is notrequired to starve any longer than usual, he/she is less likely to bedehydrated, is less likely to break his/her fast, has less time tobecome anxious and agitated and will recovery quickly enough toenjoy a breakfast with the other patients on the ward. If thisroutine is combined with regular supervision of treatment by theprescribing psychiatrist, the patient will derive the maximumbenefit from each treatment and the course will not beunnecessarily prolonged or ineffective. Outpatient ECT does notappear to be as effective in the elderly, except occasionally asmaintenance, and consequently most patients will require admissionto a specialist unit, where the effects of ECT combined withthe therapeutic milieu will hasten improvement. Familiar staffadministering the treatment and a well-designed ECT suite willhelp reduce anxiety.MAINTENANCE AND CONTINUATION ECTIn 1990 the American Psychiatric Association task force on ECTdefined continued administration of ECT over a 6 month periodto prevent relapse after induction of remission as continuationECT (C-ECT); treatment beyond 6 months was termed maintenanceECT (M-ECT). This was felt to be a viable form ofmanagement for selected patients.Maintenance ECT has been used for many years: a survey ofBritish psychogeriatricians in 1991 47 found that 20% were using itbut there is little more than anecdote to support its use in theliterature. Such studies as there are consist mainly of case-studiesand small series of hospitalized patients, all of a ‘‘naturalistic’’nature.In a 1 year follow-up of nine elderly patients, continuationtreatment, even if discontinued fairly quickly seemed to confersome lasting advantage in prevention of relapse 48 , as did Petrideset al.’s study, looking at 33 courses of C-ECT 49 . The conclusionseemed to be that where patients have responded to acute ECTbut previously failed on continuation pharmacotherapy there wascompelling evidence for C-ECT and little therapeutic alternative.The four patients in this study 49 who continued with M-ECTremained well and the five who had previously stopped did not.Naturally this result is open to other interpretations, but it doessuggest that C-ECT should be considered for those with recurrentdepression who respond well to ECT acutely but receive noprophylaxis from pharmacotherapy. The practicalities of usingoutpatient M-ECT have prevented my using it more. Bringingelderly patients to hospital for outpatient ECT early in theday, from a rural catchment area some distance from thehospital, can be problematic, they soon lose enthusiasm for thetreatment and consequently often withdraw consent. This is anissue recently addressed by Kim 50 . However, Schwarz’s findings,that rehospitalization rates were reduced by 67% after institutingM-ECT, suggest that we should try and overcome the practicaldifficulties 51 .CONSENTPopular myths about ECT are always more readily believed thanthe reality and can be part of what the patient believes they areconsenting to. Occasionally patients consent as part of their deathwish. I use a video of myself administering ECT to a patient seenbefore and after treatment, to show anxious or interested relativesand patients; no-one having seen it has then declined thetreatment. There is one study suggesting that understanding isnot enhanced by this method. The issue of informed consent indepressed patients is complex. As I have suggested, many carelittle and are prepared to do anything their doctor suggests, andpatients’ recollection of what was explained to them, after theECT and when the depression has lifted, is often vague. A carefulexplanation should be made and recorded, and if there are doubtson either side a chance to preview the ECT room or anexplanatory video may be helpful. However, it is doubtfulwhether the explanation of ECT is any less detailed than that ofmost surgical procedures and most people are willing to consentwithout seeing a video of the operation in question. Passiveacceptance of ECT is often the case in the severely depressed butthis should not prevent a full explanation, including consultingrelatives if appropriate.Involuntary ECT should never be given except within theguidelines of the relevant Mental Health legislation if we are toensure the availability of ECT as a treatment option in the future.Nevertheless, depression is such a serious and debilitating illnessthat the chance of a cure through use of ECT should never bedenied to a patient whose prognosis is favourable, simply throughdifficulty in obtaining actual written consent.SIDE EFFECTSAs already mentioned, confusion and memory loss are oftenregarded as an inevitable corollary of ECT in the elderly, but thisis clearly not the case and there are well conducted studiesshowing no objective permanent effects on memory, and in factthis often improves as a result of improvement in the depression21,41,42 . Nevertheless, there is no doubt that some patients whowere given bilateral sine wave ECT experienced long-term, evenpermanent, memory loss, and bland reassurances that this or evenbrief pulse bilateral ECT will not cause any memory loss is foolishand counterproductive. Some patients given bilateral brief pulseECT may have amnestic gaps, but can be assured that no lastingeffect on memory function, i.e. new learning or intelligence, willoccur. The situation with right unilateral brief pulse ECT isdifferent, with any subjective memory impairment being transientand undetectable 6 months later 43,44 . Patients with existingdementia may well show signs of memory impairment, even