Motor seizure monitoring during electroconvulsive therapy. P M Mayur, B N Gangadhar, N Janakiramaiah and D K Subbakrishna BJP 1999, 174:270-272. Access the most recent version at DOI: 10.1192/bjp.174.3.270
References Reprints/ permissions You can respond to this article at Downloaded from
This article cites 0 articles, 0 of which you can access for free at: http://bjp.rcpsych.org/content/174/3/270#BIBL To obtain reprints or permission to reproduce material from this paper, please write to
[email protected] http://bjp.rcpsych.org/cgi/eletter-submit/174/3/270 http://bjp.rcpsych.org/ on March 9, 2013 Published by The Royal College of Psychiatrists
To subscribe to The British Journal of Psychiatry go to: http://bjp.rcpsych.org/site/subscriptions/
B R I T I S H J O U R N A L OF P S Y C H I A T R Y (1999). 1 7 4 . 1 7 0 - 2 7 1
Motor seizure monitoring during electroconvulsive therapy PRASHANTH M. MAYUR, B. N. GANGADHAR. N. JANAKIRAMAIAH and D. K. SUBBAKRISHNA
Background The occurrence of a seizure during electroconvulsive therapy (ECT) should be confirmed. Most clinicians use motor seizure monitoring alone and recent guidelines have not considered electroencephalogram (EEG) monitoring mandatory.
Aims To examine the potential pitfalls of motor seizure monitoring. Method Consentingconsecutive patients (n=232) were prospectively studied at the first ECTsession using both motor and EEG seizure monitoring. It was ensured (by titration) that all the patients had an adequate EEG seizure. Adequate and prolonged seizures were defined according to the latest recommendations ofthe Royal College of Psychiatrists.
Results Motor seizure was inadequate in 15 (7%) of patients. EEG seizure was prolonged in 38 (16%) of patients. Fifteen patients (39%) did not have a prolonged motor seizure. Motor seizure correlated
The cuff method of motor seizure monitoring during electroconvulsive therapy (ECT) is well established. The case for electroencephalogram (EEG) monitoring was emphasised by Christensen & Koldbaek (1982) who observed that nearly half (43%) of clinically recognised seizures were inadequate when monitored using EEG. Based on a similar observation, EEG monitoring was advised in those patients who have a short 'fit' (Scott et al, 1989), especially during unilateral ECTs (McReadie et al, 1989). Fink (1987) emphasised the need for EEG monitoring in view of undetected prolonged EEG seizures. Empirical evidence for the occurrence of prolonged EEG seizures has been provided by Greenberg (1985) and more recently by Jayaprakash et a1 (1997). None the less, Abrams (1997) reported that no prolonged seizures occurred with EEG monitoring in hundreds of consecutive patients referred for ECT. However, neither the Royal College of Psychiatrists (199S), nor the American Psychiatric Association (1990) recommend mandatory EEG monitoring during ECT. Potential pitfalls of motor seizure monitoring were examined in the present study.
well (r=0.8, P 0.5).
Conclusions Motor seizure monitoring without EEG is undependable. The study provides a rational basis for the Royal College of Psychiatrists'definitionof prolonged EEG seizure.
Declarationof interest Research grants were received from Karnataka state council for scienceand ~ ~ 1997-1998.
METHOD Consecutive patients referred for ECT over the past one-year period were considered for this study. Criteria for excluding patients were: (a) age below 12 years; (b) taking xanthine alkaloids, clozaDineor anticonvul,n,except for (c) a diagnosis of epilepsy or another neurological illness; and (d) having received ECT in the past six months. Written informed consent was obtained from all the patients. All the patients ~ were right h handed. Patient ~ charac~ teristics are listed in Table 1. Patients received thiopentone (3 mgtkg), atropine (0.6 mg) and succinylcholine (0.75 mgkg) intravenously for modifica-
tion. They received positive pressure ventilation with 100% oxygen throughout the procedure. The ECT was administered using a constant current bidirectional brief pulse ECT device which delivers 800 mA current as bidirectional pulses of 1.5 ms width at a rate of 125 pulses per second. The stimulus dose can be selected by varying the length of the stimulus train (0.2-3.6 seconds). The ECT was administered with either bifrontotemporal or nondominant d'Elia electrode application. The choice of stimulus laterality was determined by the referring team. The stimulus dose was titrated from 30 mC upwards until the threshold stimulus dose was administered (Gangadhar et al, 1998). The treating psychiatrist (P.M.M.) monitored the motor seizure duration using the right ankldarm cuff method using a digital counter available on the ECT machine. This displays the time in seconds from the end of the stimulus train. The motor seizure duration was identified by the last clonic jerk. EEG (F, and F, referenced to the ipsilateral mastoids) was also recorded on two channels, displayed online on a computer screen and stored. The length of the EEG seizure was monitored by an experienced psychiatrist (B.N.G.) not involved in the stimulus administration. The stored EEG was replayed and EEG seizure termination was identified by the beginning of unequivocal absence of epileptiform Table la Patient characteristics Mean (s.d.) Range Age, yean Clinical Global Impression Scale (Guy. 1976) Threshold, rnC EEG seizure duration, s Motor seizure duration. s
29.8 (10.8) 5.4 (0.6)
13-60 4-7
88.2 (50.6) 30-180 78.7 (46.1) 25-256 54.1 (31.8) 0-176
Table lb Patient characteristics
benzodikpines; Male gender Taking tricyclic antidepressants Taking phenothiazines Taking benzodiazepines l ~ ~ Receiving ULECT Receiving BLECT
116 (50.0) 79 (34.1) 124 (53.4) 56 (24.1) ~ 106 (45.7) 126 (54.3)
ULECT, unilateral decvoconvuldvc therapy; BLECT, bilaterid elecvoconvulsive
m.
Tabla 2 Cross-tabulationof patient*
Effi and
motor seizure definitions
Motor seizure
Inadequate
EEG seizure Adequate
Prolonged
(n= 194)
(n=38)
14
I
Adequate
1 74
14
Rolonged
6
23
transients for five or more seconds on both channels (Gangadhar et al, 1995). All the patients had to have an EEG seizure of at least 25 seconds as part of the treatment procedure (Royal College of Psychiatrists, 1995). Prolonged seizure was defined as EEG seizure length of 120 seconds or longer (Royal College of Psychiatrists, 1995).T o be regarded as adequate, a motor seizure had to last for at least 15 seconds. Prolonged motor seizure was defined as motor seizure length of 90 seconds or longer (Royal College of Psychiamsts, 1995). For the whole sample (n=232), the numbers of patients who had an inadequate motor seizure but an adequate EEG seizure, and the numbers of patients who had an
adequate motor seizure but who developed prolonged EEG seizure were noted. The patients were grouped on the basis of stimulus laterality into unilateral ECT (ULECT) and bilateral ECT (BLECT) groups. The 2 statistic was used to compare the mismatches between the groups. The sample was divided on the basis of EEG seizure duration into two groups. They were: Group 1 - EEG seizure duration was not prolonged ( < I 2 0 s) and Group 2 - prolonged EEG seizures ( >120 s). Correlation coefficients of the motor and EEG seizure durations were computed for these two groups.
RESULTS Adequate motor seizure did not occur in 15 (7%) of patients. Prolonged EEG seizures occurred in 38 (16%) of patients. The motor seizure was shorter than 90 seconds in 15 (39%) of these patients. Ten patients manifested no convulsive response. Whereas the motor and EEG seizures correlated sigdicantly (Spearman's r=0.08, P
