Remifentanil supplementation of propofol during electroconvulsive therapy: effect on seizure duration and cardiovascular stability

Effects of Propofol and Propofol-Remifentanil Combinations on Haemodynamics, Seizure Duration and Recovery during Electroconvulsive Therapy

Objective

This study aimed to evaluate the effects of adding different doses of remifentanil to propofol treatment compared with propofol alone with regard to parameters, including the seizure duration, haemodynamic changes and recovery time, in patients undergoing electroconvulsive therapy (ECT).

Methods

This study was designed as a self-controlled, prospective, double-blind investigation of 17 patients between the ages of 20 and 65 years who had planned treatment with ECT at a psychiatric clinic. Group P (propofol) was administered 10 mL of normal saline after 0.5 mg kg⁻¹ intravenous (IV) bolus of propofol. Group R I (propofol plus remifentanil-1) was administered 1.5 μg kg⁻¹ of remifentanil, and group R II (propofol plus remifentanil-2) was given 2 μg kg⁻¹ of remifentanil after 0.5 mg kg⁻¹ IV bolus of propofol. The haemodynamic variables after seizure and the seizure duration were recorded. Time to return to spontaneous respiration, eye opening and achieving Aldrete score >9 were recorded.

Results

The electroencephalography seizure duration was significantly longer in groups R I (34.7±13 s) and R II (34.9±12) than in group P (24±7.5). Motor seizure duration was longer in groups R I (29.70±12.8) and R II (28.1±10) than in group P (21±7.3). The amount of total propofol was 121±21 mg in group P, 69.4±2 mg in group R I and 67±17 mg in group R II. Times to eye opening, following simple commands, and achieving Aldrete score >9 were significantly shorter in groups R I and R II than in group P.

Conclusion

ECT is a safe and effective treatment for patients with psychiatric disorders. Propofol-remifentanil anaesthesia prolongs the seizure duration and shortens the recovery time, suggesting that this combination may particularly be well suited for use in this patient group.

The Effects of Remifentanil on Hemodynamic Response Attenuation After Electroconvulsive Therapy Under Sevoflurane Anesthesia

PURPOSE

We evaluated the effects of a single loading dose of remifentanil (1 μg/kg) administered as an adjunct to sevoflurane, on the duration of seizure activity, recovery times, and hemodynamic profiles, during electroconvulsive therapy.

METHODS

The patients were randomly allocated to receive sevoflurane-saline (Group SS) or sevoflurane-remifentanil (Group SR). Sevoflurane (8%) was initiated for anesthesia induction in both groups until loss of consciousness was achieved. Remifentanil was then administered to Group SR via a 1-μg/kg intravenous bolus. Patients in Group SS received saline in the same manner. Mean arterial pressure (MAP) and heart rate (HR) were recorded before anesthetic induction (T1), at the loss of consciousness (T2), and at 0, 1, 3, and 10 minutes after the electrical stimuli were completed (T3, T4, T5, and T6, respectively).

RESULTS

Compared with the baseline values, HR increased significantly in Group SS at times T2 and T4 to T6 and decreased significantly in Group SR at time T2. When the groups were compared, we found that HR decreased significantly in Group SR at T2 and T4 to T6. Compared with baseline, MAP increased in Group SS between T3 and T6, and MAP decreased in Group SR at T2 and increased at T3 to T4. Mean arterial pressure decreased to a greater extent in Group SR than in Group SS during the T2 to T6 period. There were no group differences in seizure duration or recovery time.

CONCLUSIONS

The addition of 1-μg/kg remifentanil to anesthetic induction with sevoflurane attenuated the acute hemodynamic response to electroconvulsive therapy under sevoflurane anesthesia without adversely affecting the duration of seizure activity or the recovery profile.

Does remifentanil improve ECT seizure quality?

Studies have reported that co-adjuvant remifentanil can enhance electroconvulsive therapy (ECT) seizure quality, putatively by allowing a reduction in the dosage of the main anaesthetic agents, as the latter have anticonvulsant properties. However, whether remifentanil also has direct effects on ECT seizure quality, and by implication, treatment efficacy, is unknown. This is the first study examining the effect of adjuvant remifentanil on ECT seizure quality when the dose of conventional anaesthesia remained unchanged. A total of 96 ECT sessions (from 36 patients) were retrospectively analysed. Subjects received ECT with and without remifentanil (1 µg/kg), while the dose of thiopentone (3-5 mg/kg) or propofol (1-2 mg/kg) was unchanged. Seizure quality indices (time to slow wave activity or TSLOW, amplitude, regularity, stereotypy, post-ictal suppression) and duration were assessed through a structured rating scale by a single trained blinded rater. Linear mixed-effects models with random subject effects analysed the effect of remifentanil on seizure parameters, controlling for other variables that can affect seizure quality or duration. Remifentanil was given in 47.9 % of the ECT sessions. Co-adjuvant remifentanil had no effects on any of the seizure quality parameters analysed [TSLOW (E = -0.21, p > 0.1), amplitude (E = 0.08, p > 0.5), regularity (E = -0.05, p > 0.5), stereotypy (E = -0.02, p > 0.5), suppression (E = -0.3, p > 0.05)] or on seizure duration (E = -0.25, p > 0.1). While adjuvant remifentanil may be a useful strategy for reducing anaesthetic dosage in ECT, present evidence suggests that remifentanil does not have intrinsic properties that enhance ECT seizures.

Remifentanil in electroconvulsive therapy: a systematic review and meta-analysis of randomized controlled trials

In electroconvulsive therapy (ECT), remifentanil is often used concurrently with anesthetics. The objective of this study was to provide an up-to-date and comprehensive review on how the addition of remifentanil to anesthetics affects seizure duration and circulatory dynamics in mECT. We performed a meta-analysis of RCTs that investigated seizure duration and circulatory dynamics in patients treated with ECT using anesthetics alone (non-remifentanil group) and with anesthetics plus remifentanil (remifentanil group). A total of 13 RCTs (380 patients and 1024 ECT sessions) were included. The remifentanil group showed a significantly prolonged seizure duration during ECT compared to the non-remifentanil group [motor: 9 studies, SMD = 1.25, 95 % CI (0.21, 2.29), p = 0.02; electroencephalogram: 8 studies, SMD = 0.98, 95 % CI (0.14, 1.82), p = 0.02]. The maximum systolic blood pressure (SBP) was significantly reduced in the remifentanil group compared to the non-remifentanil group [7 studies, SMD = -0.36, 95 % CI (-0.65, 0.07), p = 0.02]. Substantial heterogeneity was observed for meta-analyses for seizure durations, but a pre-planned subgroup analysis revealed that seizure duration was prolonged only when the use of the anesthetic dose was reduced in the remifentanil group. The results of our study suggest that addition of remifentanil to anesthesia in ECT may lead to prolonged seizure duration when it allows the use of reduced anesthetic doses. Further, the addition of remifentanil was associated with reduced maximum SBP.

Which anesthetic agents for ambulatory electro-convulsive therapy?

PURPOSE OF REVIEW

There have been a considerable number of research articles published in the last 10 years outlining possible advances in the provision of electro-convulsive therapy (ECT) anaesthesia. This has resulted in a range of new drugs having been proposed as useful in the ECT setting. In particular, the use of adjuvant drugs that might improve outcomes to treatment has been investigated.

RECENT FINDINGS

There is a high level of interest in ketamine and remifentanil as agents that may alter response in ECT anaesthesia, by reducing cognitive effects, and minimizing the dose of induction agent. The numbers of patients involved in current trials have been small, and it is not possible to give a definitive answer as to the usefulness of these drugs at this stage.

SUMMARY

This review covers the major recent trials involving new and emerging treatments in ECT, and brings the reader up to date with state of knowledge of ECT anaesthesia and pharmacology.

Sevoflurane versus propofol for electroconvulsive therapy: effects on seizure parameters, anesthesia recovery, and the bispectral index

BACKGROUND/AIM

In this prospective randomized cross-over study we compare the effects of sevoflurane versus propofol for electroconvulsive therapy (ECT) anesthesia.

MATERIALS AND METHODS

Twenty four patients (ASA I-III, 18-65 years old) receiving ECT three times per week were included. Anesthesia was induced with either propofol (0.75 mg/kg iv) or 5% sevoflurane in 100% oxygen. Consecutive ECT sessions followed a 2 × 2 crossover design and a 2-day washout period until the 10th ECT. Intravenous succinylcholine (1 mg/kg) was administered while bispectral index (BIS) values were ≤60%.

RESULTS

Electromyogram and electroencephalogram seizure duration, postictal suppression index, BIS values, mean arterial blood pressure (MAP), heart rate, times to start of spontaneous respiration, eye opening, understanding verbal commands, and side effects were compared. No differences were found between the regimens for seizure activity and recovery. At the end of ECT, MAP was higher with sevoflurane. Although BIS values were higher after sevoflurane, no differences between the regimens were found in terms of the need of muscle relaxants and in hypnosis levels.

CONCLUSION

Sevoflurane (5%) may be an effective alternative to propofol for induction of anesthesia for ECT.

Ketamine for medically refractory status epilepticus after elective aneurysm clipping

BACKGROUND

Medically refractory status epilepticus, without an identifiable cause, post elective aneurysm clipping is a rare event.

OBJECTIVE

To describe the two cases of refractory status epilepticus post elective aneurysm clipping, without an identifiable cause, and discuss the potential role for early consideration of ketamine.

METHODS

Retrospectively reviewed two patients at our institution who developed refractory status epilepticus post elective aneurysm clipping, without a defined cause.

RESULTS

Two patients who underwent elective aneurysm clipping developed medically refractory status epilepticus post-craniotomy. No structural, vascular, infectious, or metabolic cause was identified. Seizure control failed with multiple medications and intravenous sedatives over the period of weeks in both. Ketamine was instituted at 20 and 40 mg/kg/min in these patients. Within hours of starting ketamine, burst suppression was obtained in both. Medications were all tapered over the next month, and both the patients recovered to be cognitively normal, with mild residual morbidity secondary to critical care polyneuropathy.

CONCLUSIONS

Refractory status epilepticus, in the absence of an identifiable etiology, in elective aneurysm clipping is a rare event. Consideration should be given for the early use of ketamine in refractory status epilepticus.

Sevoflurane/remifentanil versus propofol/remifentanil for electroconvulsive therapy: comparison of seizure duration and haemodynamic responses

OBJECTIVE

To compare the anaesthetic and convulsive effects of sevoflurane/remifentanil versus propofol/remifentanil combination in electroconvulsive therapy (ECT).

METHODS

In this prospective, randomized double-blind study, patients diagnosed with treatment-resistant depression were included for ECT. Prior to treatment, 1 µg/kg remifentanil was intravenously administered to all patients, followed by anaesthetic induction with either 0.5 mg/kg propofol or 8% sevoflurane. Following muscular paralysis with succinylcholine and hypnosis, bitemporal ECT was applied. Vital signs, depth of sedation, recovery parameters, motor and electroencephalography (EEG) convulsion activity and postictal suppression index scores were recorded.

RESULTS

A total of 120 sessions of ECT were administered to 12 patients. Heart rate was higher in the sevoflurane group than the propofol group. Compared with the sevoflurane group, bispectral index level was lower in the propofol group during the induction period and higher during the recovery period. Anaesthetic induction and recovery times were lower, and average motor and EEG convulsion activity was longer, in the propofol group than in the sevoflurane group.

CONCLUSION

Propofol/remifentanil is more successful compared with sevoflurane/remifentanil in anaesthesia management during ECT since it provides quick induction and recovery, longer seizure activity and stable haemodynamics.

Comparison of enflurane and propofol in electroconvulsive therapy, a randomized crossover open preliminary study on seizure duration and anaesthetic recovery

BACKGROUND AND OBJECTIVES

Electroconvulsive therapy (ECT) is commonly used for treatment of depression, mania and affective disorders. Anaesthetics for general anaesthesia during ECT should have rapid onset, rapid emerge, not interfere with seizure activity and not shorten seizure duration. The aim of this study is to compare effects of enflurane, a pro-convulsive anaesthetic agent, and propofol on seizure durations, postictal suppression index and recovery times during electroconvulsive therapy.

METHODS

Unpremedicated subjects were divided into two groups according to induction of anaesthesia. Patients were induced for ECT with 5% enflurane in group E and 1.2mg.kg(-1) propofol in group P until loss of consciousness. The durations of electroencephalogram (EEG) and motor seizures, postictal suppression index, time to spontaneous breathing, duration of eye opening, and obeying commands were recorded.

RESULTS

There was no statistically significant difference between the groups regarding motor and EEG seizure times and postictal suppression index on the EEG records. Recovery times (times of starting spontaneous breathing, eye opening, and obeying command) were significantly shorter in group E compared to group P. No nausea or vomiting were observed and no ECG abnormality was noted except transient sinus bradycardia and sinus tachycardia.

CONCLUSIONS

Although sufficient seizure for the treatment was provided during enflurane anaesthesia, any additional benefit was not revealed regarding seizure times or postictal suppression index when compared to propofol anaesthesia. On the other hand, recovery times after enflurane anaesthesia were shorter than propofol anaesthesia. However, there is still a need for further study in different ETCO(2) levels.

The difficult-to-treat electroconvulsive therapy patient - Strategies for augmenting outcomes

BACKGROUND

Several treatment strategies for augmenting outcomes with ECT (concurrent antidepressant treatment, frequency of ECT treatments, hyperventilation and use of remifentanil) are discussed in the context of a difficult clinical case, accompanied by a review of the relevant existing literature.

METHODS

Literature on the above aspects of ECT technique was identified via a PubMed search and was critically reviewed.

RESULTS

There is preliminary evidence that concurrent administration of some antidepressant medications may be useful in the highly treatment resistant patient, though due attention should be given to potential risks in combining these with ECT; reduction of the treatment frequency to twice a week; hyperventilation prior to each treatment; and the use of remifentanil to minimise the dosage of induction anaesthetics with anticonvulsant properties, may be useful strategies to enhance seizure production in cases where a high or rapidly rising seizure threshold is a major impediment to ECT treatment.

LIMITATIONS

It should be noted that empirical evidence for the effectiveness of each of the above strategies in producing better outcomes with ECT is not definitive, pointing to the need for further research in these areas.

CONCLUSIONS

The above strategies may be useful in clinical ECT practice, particularly in patients who are apparently treatment resistant, but the practitioner should be aware that the level of evidence underpinning these approaches is at present, preliminary.

Frequency of and rationales for the combined use of electroconvulsive therapy and antiepileptic drugs in Austria and the literature

Our aim was to observe the frequency of combination therapy using antiepileptic drugs (AEDs) and electroconvulsive therapy (ECT) in Austria and the literature, and to provide rationales and recommendations based on clinical and molecular properties. The responsible ECT leaders of eight Austrian departments were contacted for information about combination therapy. A computerized PubMed database search was performed and supplemented by cross-referencing from papers, review articles and psychiatric manuals. The frequency of combination therapy in Austrian departments ranges between 0 and 85.7%. In 17 studies enrolling a total of 189 patients, 87 (46.0%) patients received combination therapy. Of these 87 patients, nine (10.3%) reported adverse effects. ECT and AEDs show overlapping clinical and molecular properties. Combination therapy is an observed reality and, according to the currently available literature, feasible. A comparison of clinical and molecular properties indicates possible augmentative effects, making combination therapy a promising alternative in treatment-resistant cases. But there is still a clear need for prospective case controlled data concerning side effects, safety profiles and effectiveness until it can be recommended.

Remifentanil/Thiopental combination and seizure length in electroconvulsive therapy

In an effort to see if use of high-potency opioid combined with lower-than-usual dose barbiturate results in longer seizure length in electroconvulsive therapy, we retrospectively examined data from 56 patients. For each case, 1 seizure with thiopental alone and 1 with thiopental combined with remifentanil were compared. Longer mean electroencephalographic seizure length with the combination slightly missed statistical significance, whereas motor seizure duration was not statistically significantly different between the 2 strategies. We conclude that if thiopental is used for anesthetic induction in electroconvulsive therapy in the dose range described herein, modest dose reduction and combination with remifentanil does not reliably prolong seizure duration.

Effects of general anesthetic agents in adults receiving electroconvulsive therapy: a systematic review

OBJECTIVES

Our primary objective was to conduct a systematic review to determine the differential effects of general anesthetic agents on electroconvulsive therapy (ECT) induced motor and electroencephalogram seizure duration. Our secondary objective was to determine the differential effects of induction agents on emergence time, recovery time, and the occurrence of adverse cardiac events and drug effects.

MATERIALS AND METHODS

We searched 4 electronic databases for randomized, crossover, and parallel trials. The weighted mean difference was calculated for continuous variables, whereas the risk difference was assessed for dichotomous variables. We combined crossover- and parallel-designed trials using the inverse variance method, and the random-effects model was used throughout.

RESULTS

Forty-one randomized trials involving 14 induction agents were included. The quality of trials was poor. Clinical and statistical heterogeneity were identified throughout. The most commonly studied comparison was methohexital versus propofol, where the mean motor seizure duration with methohexital was longer compared with that of propofol (weighted mean difference, 9.06 seconds; 95% confidence interval, 5.72-12.40). However, combining methohexital or propofol with a short-acting opioid prolonged seizure duration. Small but significant variations in emergence and recovery times were identified. Inadequate data were available to draw conclusions regarding adverse cardiac events and drug effects. No deaths were reported.

CONCLUSIONS

Whereas the relationship between ECT seizure length and efficacy remains unclear, all of the available induction agents in this review would be appropriate for ECT. When the clinician needs to prolong seizure length, methohexital or the addition of a short-acting opioid to methohexital or propofol should be considered. The small variations in emergence and recovery times should not govern the choice of an induction agent.

The effects of age and sex on electroconvulsive therapy using remifentanil as the sole anesthetic agent

OBJECTIVE

This study examines electroencephalographic (EEG) and motor seizure duration and dynamic energy according to age and sex using remifentanil anesthesia in standard electroconvulsive therapy (ECT).

BACKGROUND

In an earlier study, we showed that remifentanil provides superior anesthesia for ECT in terms of providing adequate seizure duration with lower stimulus doses in patients refractory to maximal ECT settings with methohexital.

METHODS

Patients, refractory to maximal ECT settings with methohexital, received remifentanil as the sole anesthetic agent. Stimulus dose was determined by the dose-titration method. Electroencephalographic seizure duration, motor seizure duration, and dynamic energy in joules (j) were compared between male and female subjects and among patients aged 40 years or younger, older than 40 years but aged 65 years or younger, and older than 65 years.

RESULTS

Seventy-two patients were included in the study. There was no significant difference in remifentanil doses between female and male subjects. There was no significant statistical difference between female and male subjects regarding motor seizure duration, EEG seizure duration, or dynamic energy (P > 0.05). There were significant statistical differences among different groups in terms of motor seizure duration, EEG seizure duration, and dynamic energy (P< 0.05). The younger age group had longer motor and EEG seizure durations and required lower dynamic energy.

CONCLUSIONS

There is no significant effect of sex on ECT with remifentanil anesthesia regarding EEG or motor seizure durations or dynamic energy; however, statistically significant differences were observed based upon age. Younger patients had both increased motor and EEG seizure duration compared with older patients who may require higher stimulus doses than younger patients for comparable motor and EEG seizure durations.

Effects of the addition of remifentanil to propofol anesthesia on seizure length and postictal suppression index in electroconvulsive therapy

OBJECTIVE

Propofol is a widely used anesthetic agent for electroconvulsive therapy (ECT). However, there are concerns that its anticonvulsant effect may interfere with the efficacy of ECT. We aimed to investigate the effects on seizure activity of the addition of the opiate remifentanil to propofol anesthesia for ECT.

METHODS

A retrospective analysis of 633 treatments in 73 patients was conducted. At each treatment, patients had received anesthesia with propofol alone or propofol plus remifentanil, depending on which anesthetist was providing anesthesia. Analysis of variance was performed to examine the effects of the anesthetic used, the electrode placement, the dose of electricity administered, and the stage in the course of treatment. Dependent variables were electroencephalogram seizure length and postictal suppression index (PSI).

RESULTS

Addition of remifentanil resulted in a small but significantly lower dose of propofol being used to induce unconsciousness. Addition of remifentanil affected seizure length, mainly related to an effect when placement was right unilateral (F = 5.70; P = 0.017). There was also a significantly increased PSI (F = 4.3; P = 0.039), which was not dependent on dose or on placement.

CONCLUSIONS

The data suggest that addition of remifentanil to propofol anesthesia significantly alters seizure indices. This may be secondary to a reduction in the amount of propofol required or to an independent effect of remifentanil. The increase in PSI in particular suggests that addition of remifentanil may improve clinical response. However, this can only be examined in a randomized controlled trial.

Cognitive impairment following electroconvulsive therapy--does the choice of anesthetic agent make a difference?

The range of drugs available to provide anesthesia for patients undergoing electroconvulsive therapy (ECT) is ever increasing. Initially, anesthetic agents were selected on the basis of their capacity not to antagonize the induced seizure. This was not always a simple task because almost all general anesthetic agents have "in built" antiepileptic activity. Nonbarbiturate agents such as propofol have been successfully used as alternatives to thiopental and methohexitone, but this drug too has antiepileptic properties. Most recently, opioid-like drugs such as remifentanil have been used, and there has been renewed interest in ketamine, a phencyclidine derivative. Attention has also focused on whether the anesthetic agent selected may affect the cognitive impairment seen after ECT. Studies in this area are limited, but early results suggest that agents such as ketamine may have particular benefit. This article reviews the current literature dealing with anesthesia and postoperative cognitive impairment in general and with regard to ECT in particular.