The effect of remifentanil on seizure duration and acute hemodynamic responses to electroconvulsive therapy

The Effects of Remifentanil, Dexmedetomidine, and Metoral as Adjuncts to Thiopental on Hemodynamic Status After Electroconvulsive Therapy in Patients with Major Depressive Disorder: A Randomized Controlled Clinical Trial

Background

Depression is a prevalent mental disorder affecting more than 300 million people of all ages globally. Despite being the first-line treatment for depression, antidepressant medications are only effective for 60% - 70% of patients. Electroconvulsive therapy (ECT) is an effective treatment for severe cases, although it can result in short-term side effects.

Objectives

This study aimed to compare the effectiveness of remifentanil, dexmedetomidine, and metoral as premedications for ECT in patients with major depressive disorder (MDD).

Methods

In this prospective double-blinded randomized controlled clinical trial, a total of 120 MDD patients aged 18 - 60 were included. They were randomly assigned to receive remifentanil, dexmedetomidine, or metoral in combination with thiopental before ECT. Hemodynamic responses (mean arterial blood pressure, pulse rate, arterial blood oxygen saturation), seizure duration, recovery time, agitation scores, and patient satisfaction scores (reverse coded) were measured and compared.

Results

Dexmedetomidine exhibited superior hemodynamic control with lower mean arterial blood pressure (P < 0.001) and pulse rate (P < 0.001) than remifentanil and metoral. Patients receiving dexmedetomidine or remifentanil showed reduced agitation (P < 0.001) and better satisfaction than the metoral group (P < 0.001). Remifentanil displayed intermediate outcomes, while metoral exhibited the least favorable results. Seizure duration was not significantly different between the dexmedetomidine and remifentanil groups (P = 0.843).

Conclusions

Dexmedetomidine is considered the most satisfactory group due to the better control of blood pressure, heart rate, and agitation and better patient satisfaction despite the longer recovery time.

Electroconvulsive Therapy in Elderly Patients With Cerebral Aneurysms: A Systematic Review With Clinical Recommendations

INTRODUCTION

Electroconvulsive therapy (ECT) is commonly used in the elderly due to its proven efficacy and safety profile. However, presence of cardiovascular comorbidities such as cerebral aneurysms may complicate the course of treatment. Our knowledge about the possible risk factors and precautionary measures remains limited.

METHODS

We performed a systematic review of published case reports of elderly patients with cerebral aneurysms treated with ECT.

RESULTS

A total of 11 cases were included for the review. One patient died because of subarachnoid hemorrhage (SAH) secondary to ictal hypertensive surge during treatment with ECT.

DISCUSSION

Risk factors such as history of hypertension, age of the patient, extent of the ictal surge in blood pressure, efficacy of prophylactic treatment to control surge in blood pressure and characteristics of cerebral aneurysm each elevated the risk of complication in these cases. We reviewed safety measures based on the evidence from the current literature available.

CONCLUSION

ECT is safe in elderly patients with cerebral aneurysms provided appropriate safety measures are employed. Screening for cerebral aneurysms in high risk patients, effective prevention and management of blood pressure elevation acutely during ECT is the best practice to avoid adverse outcomes.

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.

Effect of adding dexmedetomidine or remifentanil to thiopental in patients with mood disorder candidate for electroconvulsive therapy

Electroconvulsive therapy (ECT) is one of the appropriate treatments for many neuropsychiatric patients, especially those with mood disorders. Short-term complications of ECT include agitation and postictal. In this study, we compared the addition of dexmedetomidine or remifentanil to thiopental as the main anaesthetic used in ECT. In this double-blind randomised clinical trial, 90 patients with mood disorders (candidates for ECT) were divided into two groups based on their therapy: dexmedetomidine or remifentanil. In the first group (DG), patients were slowly injected intravenously with 0.5 μg/kg dexmedetomidine before induction of anesthesia. In the second group (GR), 100 μg of remifentanil was slowly injected intravenously.In addition, we collected demographic information such as respiratory rate, heart pulse rate, seizure time, mean of arterial blood pressure, recovery duration and the oxygen arterial saturation recorded after recovery. Data obtained were analysed by use of statistical software, SPSS-23. The mean age of both groups was approximately 37 years with the majority being men. There was no significant difference between the two groups in terms of age and sex, blood pressure, heart rate, duration of seizures and arterial oxygen saturation before ECT. The mean blood pressure and heart rate in the recovery group were lower in the dexmedetomidine group than in the remifentanil group and the hemodynamics in the dexmedetomidine group were more stable. The recovery time in the dexmedetomidine group was longer than that of the remifentanil group (p = 0.001). Both groups had approximately the same satisfaction and the rate of agitation after ECT was the same. Both remifentanil and dexmedetomidine as adjuvants lead to a decrease in patients' post-ECT hyperdynamic responses. In our study, we demonstrated that the effect of dexmedetomidine is greater than remifentanil. On the other hand, neither dexmedetomidine nor remifentanil had a negative effect on seizure duration, but dexmedetomidine significantly prolonged recovery time, when compared to remifentanil.

Remifentanil as an adjunct to anaesthesia for electroconvulsive therapy fails to confer long-term benefits

BACKGROUND

Adding the μ-opioid receptor agonist remifentanil to agents used to induce general anaesthesia in electroconvulsive therapy (ECT) can reduce the required doses of induction agents and their unfavourable effects on seizure threshold and quality. However, whether remifentanil has favourable long-term treatment effects in terms of response and remission rates, speed of response and remission, and side-effects has not been studied.

METHODS

This retrospective, register-based cohort study involved patients with major depression consecutively treated at two units at different hospitals in Norway with the same ECT procedure. Both units used thiopental for ECT anaesthesia, but only one unit added remifentanil (R+; n=47; 541 sessions), whereas the other did not (R-; n=119; 1166 sessions). A Cox proportional hazards model for interval-censored data was conducted to examine the effects of remifentanil on the time to response and remission from depressive symptoms, whilst adjusting for age, sex, and baseline depression score.

RESULTS

Both R+ and R- patients showed substantial reductions of depressive symptoms, with no difference in the response (76% in both groups) or remission (63% vs 65%) rate. However, R+ patients responded (hazard ratio=0.59; 95% confidence interval: 0.4-0.8) and remitted (hazard ratio=0.72; 95% confidence interval: 0.5-1.0) more slowly, and reported more often side-effects of nausea (30% vs 8%; P<0.001), dizziness (22% vs 8%; P=0.027), and headache (48% vs 23%; P=0.004).

CONCLUSIONS

The use of adjunctive remifentanil was associated with more short-term side-effects and no favourable long-term clinical outcomes. The practice of routinely adding remifentanil to barbiturate anaesthesia should therefore be reconsidered.

Minimum Effective Doses of Succinylcholine and Rocuronium During Electroconvulsive Therapy: A Prospective, Randomized, Crossover Trial

BACKGROUND

Neuromuscular blockade is required to control excessive muscle contractions during electroconvulsive therapy (ECT). In a crossover, assessor-blinded, prospective randomized study, we studied the minimum effective dose (MED) of succinylcholine and rocuronium for ECT. The MED was the lowest dose to provide a predefined qualitative measure of acceptable control of muscle strength during induced convulsions.

METHODS

Succinylcholine (0.8 mg kg) or rocuronium (0.4 mg kg) was randomly administered in 227 ECT sessions to 45 patients. The dose was incrementally increased or decreased by 10% based on 2 psychiatrists' (blinded to treatment) assessment of "acceptable" or "not acceptable" control of evoked muscle contractions (sufficient versus insufficient or excessive paralysis). The neuromuscular transmission was monitored quantitatively until full recovery.

RESULTS

In our study, the MEDs of succinylcholine and rocuronium to produce acceptable ECT conditions in 50% of patients (MED50ECT) were 0.85 mg kg (95% confidence interval [CI], 0.77-0.94) and 0.41 mg kg (95% CI, 0.36-0.46) and in 90% of patients (MED90ECT) were 1.06 mg kg (95% CI, 1.0-1.27) and 0.57 mg kg (95% CI, 0.5-0.6), respectively. Nadir twitch height for acceptable muscle activity was 0% (0-4) and 4% (0-30; P < 0.001), respectively, and the time to recovery of the neuromuscular transmission was 9.7 ± 3.5 and 19.5 ± 5.7 minutes, respectively.

CONCLUSIONS

A twitch suppression of >90% is needed for control of motor contractions during ECT. The initial ECT dose of succinylcholine should be selected based on each patient's preprocedural condition, ranging between 0.77 and 1.27 mg kg to produce acceptable muscle blockade in 50% to 90% of patients. Rocuronium-neostigmine combination is a safe alternative if appropriately dosed (0.36-0.6 mg kg) and monitored.

Premedication effect of dexmedetomidine and alfentanil on seizure time, recovery duration, and hemodynamic responses in electroconvulsive therapy

Introduction:

Electroconvulsive therapy (ECT) is an effective treatment for many mental disorders, especially severe and persistent depression, bipolar disorder, and schizophrenia. The aim of this study is to compare the effect of dexmedetomidine and alfentanil on agitation, satisfaction, seizure duration, and patients hemodynamic after ECT.

Materials and Methods:

In a three phase crossover randomized clinical trial, 75 patients aged between 18 and 50 years and candidate for ECT were enrolled and assigned into three groups (25 patients in each group). All patients, respectively, took premedication of dexmedetomidine, alfentanil, or saline in three consecutive phases. Patients received 0.5 μg/kg dexmedetomidine, 10 μg/kg alfentanil or normal saline intravenously, 10 min before induction. Finally, seizure and recovery duration, satisfaction and agitation score, and hemodynamic parameters were evaluated.

Results:

There was no significant difference about seizure duration, agitation score, and hemodynamic parameters between groups but recovery duration was significantly lower in the control group than dexmedetomidine (P = 0.016) and alfentanil group (P = 0.0001). Patients’ satisfaction was significantly higher in intervention groups (alfentanil and dexmedetomidine groups) (P = 0.0001).

Conclusion:

Given the equal effects of alfentanil and dexmedetomidine, it seems that choosing one of these two drugs for premedication of patients undergoing ECT is appropriate. Drug choice is influenced by numerous factors such as accessibility of each drug and the dominance of anesthesiologist and psychiatrist.

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.

The Effect of Adjuvant Remifentanil with Propofol or Thiopentone on Seizure Quality during Electroconvulsive Therapy

In order to optimise outcome to electroconvulsive therapy (ECT), there has been a trend to remifentanil as an adjunct to standard intravenous induction agents. This has allowed a reduction in the dose of anaesthetic agent, and usually an improved response to stimulation. However there have been no previous studies to ascertain whether this improvement is simply as a result of the reduced dose of anaesthetic agent or whether remifentanil itself might possess epileptogenic properties. This retrospective case-controlled study examined ECT outcomes, determined by electroencephalography (EEG) quality analysis, in patients who received ECT with or without remifentanil, where there was no dose reduction in the anaesthetic agent. There were no improvements seen in the measurements of any EEG parameter, including seizure duration. These observations suggest that remifentanil does not possess any intrinsic proconvulsant activity and that any improvement in outcome seen with its use is as a result of dose reduction in the IV anaesthetic agent.

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.

The effect of propofol-remifentanil anesthesia on selected seizure quality indices in electroconvulsive therapy

BACKGROUND

Use of a short-acting opiate to potentiate anesthetic induction agents has been shown to increase seizure duration in electroconvulsive therapy (ECT), but little is known of the effect of this combination on indices of seizure quality.

OBJECTIVE

To determine whether anesthetic modality affects commonly provided indices of seizure quality.

METHODS

Twenty-five subjects were given propofol 2 mg/kg body weight for their first ECT session, at which time seizure threshold was titrated. Subjects thereafter alternated between that anesthetic regimen or propofol 0.5 mg/kg plus remifentanil 1 mcg/kg. Linear mixed models with random subject effect, adjusting for electrode placement, electrical charge, and number of treatments, were fit to estimate effect of anesthesia on seizure duration and several standard seizure quality indices (average seizure energy, time to peak electroencephalography (EEG) power, maximum sustained power, interhemispheric coherence, early and midictal EEG amplitude, and maximum sustained interhemispheric EEG coherence).

RESULTS

Propofol-remifentanil anesthesia significantly lengthened seizure duration and was associated with longer time to reach maximal EEG power and coherence as well as maximal degree of interhemispheric EEG coherence. No effect was seen on early ictal amplitude or average seizure energy index.

CONCLUSIONS

Propofol-remifentanil anesthesia prolongs seizure duration and has a significant effect on some, but not all, measures of seizure quality. This effect may be of some benefit in cases where adequate seizures are otherwise difficult to elicit. Varying anesthetic technique may allow more precise investigation of the relationships between and relative impacts of commonly used seizure quality indices on clinical outcomes and ECT-related cognitive side effects.

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.

Effects of remifentanil on convulsion duration and hemodynamic responses during electroconvulsive therapy: a double-blind, randomized clinical trial

BACKGROUND

Among the drugs used for the induction of anesthesia for electroconvulsive therapy (ECT), thiopental induces a greater degree of cardiovascular alteration than other agents. Remifentanil has been found to reduce blood pressure and heart rate when administered as an adjuvant during general anesthesia, with unknown effects on the duration of motor or electroencephalographic seizure activity during ECT. The purpose of this prospective, randomized, double-blind, placebo-controlled, crossover study was to evaluate the effects of supplementing thiopental anesthesia with remifentanil on convulsion duration and cardiovascular response during ECT.

METHODS

Twenty-four American Society of Anesthesiologists I and II patients receiving 6 sessions of ECT were randomly allocated to 2 groups. All patients were premedicated with atropine (0.4 mg, intravenously), then anesthesia was induced by thiopental (1.0 mg/kg), succinylcholine (0.5 mg/kg), and remifentanil (1.0 microg/kg) in the case group or normal saline (3 mL) in the control group in a crossover format. Stimulus amplitude for applying ECT was kept constant during the sessions of treatment in the course of study for each patient. Hemodynamic parameters, convulsion duration, and recovery parameters were recorded. Statistical analysis was done using paired t tests.

RESULTS

There was no statistically significant difference between the groups regarding convulsion duration, recovery times to eye opening, obeying specific commands, and walking without help. Remifentanil significantly attenuated the increase in heart rate and arterial blood pressure (P < 0.05).

CONCLUSIONS

Remifentanil (1 microg/kg) administered before thiopental (1 mg/kg) has no adverse effect on the duration of ECT-induced convulsion and recovery time, but it can attenuate the increase in heart rate and arterial blood pressure.

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.

Effects of landiolol on hemodynamic response and seizure duration during electroconvulsive therapy

PURPOSE

This study was done to evaluate the effect of landiolol, an ultra-short-acting beta-blocker, on the hemodynamic response and the duration of seizure activity during electroconvulsive therapy (ECT).

METHODS

We designed a prospective, randomized, double-blinded, placebo-controlled, crossover study. Fourteen psychiatric patients participated. Landiolol (0.1 mg x kg(-1) or 0.2 mg x kg(-1)) or saline (placebo) was administered IV 1 min before the induction of anesthesia. Unconsciousness was induced with propofol 1.0 mg x kg(-1) IV, and muscle paralysis was produced with succinylcholine 0.6 mg x kg(-1) IV. Subsequently, electrical stimulus was administered to elicit a seizure, and the duration of the motor seizure activity was noted.

RESULTS

The heart rate (HR) and rate-pressure product (RPP) before ECT were significantly decreased in the 0.2 mg x kg(-1) landiolol group compared with these parameters in the placebo and 0.1 mg x kg(-1) landiolol groups. Both the 0.1 mg x kg(-1) and 0.2 mg x kg(-1) doses significantly attenuated the degree of tachycardia and RPP after ECT in comparison with the placebo group. Pretreatment with 0.2 mg x kg(-1) landiolol resulted in a significantly shorter duration of motor seizure than that in the placebo group (21 +/- 13 s vs 27 +/- 12 s).

CONCLUSION

As the landiolol dose of 0.2 mg x kg(-1) caused shorter seizure duration, and because the hemodynamic effects after ECT of the 0.1 mg x kg(-1) and 0.2 mg x kg(-1) doses were similar, it was concluded that a 0.1 mg x kg(-1) landiolol bolus was the appropriate dose pretreatment before ECT.

Comparison of remifentanil and fentanyl in anaesthesia for elective cardioversion

This prospective, randomized, double-blind study was designed to compare the recovery characteristics of remifentanil and fentanyl in combination with propofol for direct current cardioversion. Patients undergoing elective cardioversion received either intravenous fentanyl 1 microg/kg (n=33) or remifentanil 0.25 microg/kg (n=30) and propofol was titrated to a Ramsay sedation score of 5 by slow intravenous injection. Heart rate, systolic, diastolic and mean blood pressures decreased significantly following sedation in both groups but did not show a significant difference between the groups. Time to answer a question (306 +/- 83 vs 383 +/- 131s, mean +/- SD, P=0.014) and time to sit up (412 +/- 90 vs 511 +/- 126s, P=0.002) were significantly shorter in the remifentanil group compared to the fentanyl group. Side-effects and patient discomfort were similar for both groups. Remifentanil can be used as a suitable supplement to propofol for direct current cardioversion and may provide a faster recovery profile than fentanyl.

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

OBJECTIVES

Electroconvulsive therapy (ECT) is standard treatment of severe depression. The induction of a seizure is a core event in successful ECT. Although propofol is a frequently used anesthetic agent, one of its limitations is a reduction of seizure duration. No such effects have been reported regarding remifentanil, an ultrarapid-acting opioid that is used to induce and maintain anesthesia. The simultaneous administration of propofol and remifentanil may have similar safety and efficacy in terms of induction of anesthesia during ECT as propofol alone and significantly increase seizure duration.

METHODS

Twenty-one ECT patients (10 men, 11 women, aged 24 to 81 years) were recruited. Muscle paralysis was achieved with succinylcholine (0.5-0.75 mg/kg intravenously [IV]). Unconsciousness was induced by either propofol (1 mg/kg IV) or propofol (0.5 mg/kg IV) + remifentanil (1 microg/kg) in a crossover format. ECT was administered according to established clinical protocols at the Sheba Medical Center, Israel. No changes in ECT current were permitted in the 2 protocols of each patient. Statistical analysis was based on paired t tests.

RESULTS

In all but 2 cases, seizure duration was significantly longer in the remifentanil group than in the control group (motor seizure 53.7 +/- 28.3 seconds vs. 29.5 +/- 10.9 seconds, t = 4.017, P = 0.0007; Electroencephalographic (EEG) seizures 60.8 +/- 25.1 seconds vs. 40.1 +/- 17.0 seconds, t = 3.971, P = 0.001). No significant differences were found in mean recovery time, post-treatment elevation in blood pressure, heart-beat, or oxygen saturation.

CONCLUSION

During anesthesia, the addition of remifentanil to propofol appears to be as effective as propofol alone with regard to anesthesia efficacy and cardiovascular function while significantly increasing seizure duration. Whether this discovery is of relevance to the clinical efficacy of ECT remains to be tested.

The Comparative Effects of Remifentanil or Magnesium Sulfate Versus Placebo on Attenuating the Hemodynamic Responses After Electroconvulsive Therapy

In this prospective, randomized, double-blind, placebo-controlled, crossover study we compared the effects of remifentanil or magnesium sulfate (MgSO4) versus placebo in attenuating the sympathetic response to electroconvulsive therapy. Twenty adults underwent a total of 115 anesthetics for therapeutic electroconvulsive therapy. Patients were randomly allocated twice into each of the three test groups: placebo control, MgSO4 30 mg/kg, or remifentanil 1.0 microg/kg. Systolic and diastolic arterial blood pressures, heart rate, and oxygen saturations were recorded before IV access was established. Anesthesia was induced with thiopental 4 mg/kg. The trial drug was then administered and neuromuscular blockade was followed with succinylcholine 0.5 mg/kg before electroconvulsive therapy was performed. All measurements were repeated at 0, 1, 3 and 10 min after the seizure ended. Remifentanil and MgSO4 produced a statistically significant attenuation of the increase in systolic arterial blood pressure at 0, 1, and 3 min (P < 0.05). Remifentanil, but not MgSO4 or placebo, attenuated the increase in heart rate at 1 and 3 min but not the peak rate. Remifentanil increased the duration of apnea (mean 90 s), with no other adverse respiratory effects. Mean seizure duration time was 33 (+/- 14) s, with no difference among the groups. In conclusion, remifentanil 1.0 microg/kg and MgSO4 30 mg/kg attenuated the systolic arterial blood pressure response to electroconvulsive therapy without reducing the duration of seizure activity. Because MgSO4 has less effect on HR, it might offer advantages over remifentanil in patients at risk for post-electroconvulsive therapy bradycardia.

Effects of remifentanil and alfentanil on seizure duration, stimulus amplitudes and recovery parameters during ECT

BACKGROUND AND OBJECTIVE

Propofol may decrease seizure duration in electroconvulsive therapy. Although not proven, prolonged seizures may be more efficacious. The goal of this study was to evaluate and compare effects of alfentanil and remifentanil on seizure duration, recovery parameters and degree of stimulus amplitude in patients undergoing electroconvulsive therapy.

METHODS

Twenty-four ASA I-II patients enrolled in this prospective, randomized trial, each receiving a total of seven electroconvulsive therapies. Patients were randomized to receive only Propofol, group P (0.75 mg kg-1, n=8), Propofol with alfentanil, group A (10 microg kg-1 alfentanil+0.5 mg kg-1 Propofol, n=8) and Propofol with remifentanil, group R (1 microg kg-1 remifentanil +0.5 mg kg-1 propofol, n=8) via an iv route. Supplemental doses of propofol were given as required to achieve loss of consciousness. Succinylcholine 0.5 mg kg-1 iv was given to all groups for muscular paralysis. We recorded hemodynamic parameters, cortical and motor seizure durations, and recovery parameters.

RESULTS

Mean motor seizure duration was found to be significantly longer in patients receiving propofol-remifentanil anesthesia (53.3+/-13.6 s) and propofol-alfentanil anesthesia (52.2+/-0.4 s) compared with propofol anesthesia (37.6+/-9.2 s) (P=0.001). Recovery parameters and stimulus amplitudes were similar in groups A and R; significantly different from group P (P=0.001).

CONCLUSIONS

Adding 10 microg kg-1 alfentanil or 1 microg kg-1 remifentanil to reduced doses of propofol provided unconsciousness and increased seizure durations. For patients who need higher stimulus amplitudes for longer seizure durations, combining low-dose propofol with alfentanil or remifentanil may be good alternative regimens for ECT.

The comparative hemodynamic effects of methohexital and remifentanil in electroconvulsive therapy

Remifentanil is a short acting opioid frequently used to supplement general anesthesia for brief procedures. Narcotic agents are known for their ability to blunt autonomic responses to stimuli such as laryngoscopy and intubation and do not alter seizure threshold. We hypothesized that the combination of remifentanil and methohexital for induction would produce favorable suppression of sympathetic response during electroconvulsive therapy (ECT). With Institutional Review Board approval and informed consent, patients were enrolled in a prospective, randomized, double-blind, crossover study of methohexital alone versus remifentanil with an adjuvant of low-dose methohexital. One hundred ten ECT treatments were evaluated and subjects were treated in an alternating fashion with one of two induction protocols: Methohexital alone in an 80-100 mg IV bolus or remifentanil 500 mcg IV bolus combined with methohexital 40 mg IV. Bilateral ECT was performed in standard fashion and systolic blood pressure and heart rate were recorded throughout the procedure. No significant differences were found in baseline hemodynamic values between the two groups. Heart rate was significantly lower in the remifentanil group versus methohexital group at one minute post-induction and just prior to ECT stimulus. Pre-ECT systolic blood pressure was not significantly different between the two groups. Heart rate remained lower in the remifentanil group at all measured timepoints during the treatment and continuously for five minutes after the seizure. Systolic blood pressure was significantly lower at one minute following the end of seizure and five minutes after end of seizure. Remifentanil's short duration of action, favorable side effect profile, potential proconvulsant activity and ability to suppress hemodynamic response make it a potential novel drug for ECT induction.

A retrospective comparison of remifentanil versus methohexital for anesthesia in electroconvulsive therapy

The electroconvulsive therapy (ECT) service at West Virginia University conducted a retrospective analysis of 24 patients who received bilateral ECT between November 1998 and December 2003. Patients were treated with a standard methohexital-based anesthetic. Twenty-four patients became completely or relatively refractory to maximum settings on the ECT device and were then switched to remifentanil as the sole induction agent. Seizure threshold was established by stimulus dose retitration. Stimulus dose in total charge (mC) and dynamic energy (J) was significantly lower with the remifentanil anesthetic versus methohexital. (P < 0.0001) Resulting motor and EEG seizure duration in patients was significantly longer receiving the remifentanil anesthetic versus methohexital. (P < 0.0001) Previous reports describe a rise in seizure threshold in patients for repeated ECT. Although this rise occurred during the treatment course using a methohexital anesthetic, this effect was greatly diminished when remifentanil was used as the sole anesthetic agent. We conclude that remifentanil can provide improved seizure response to ECT in patients who are refractory to seizure induction after a standard methohexital anesthetic. We also conclude that the increase in stimulus dose typically required with repeated treatments is related to the anesthetic regimen.

Combination propofol-alfentanil anesthesia for electroconvulsive therapy in patients receiving monoamine oxidase inhibitors

Two patients who had failed outpatient treatment of depression were given electroconvulsive therapy while simultaneously being treated with monoamine oxidase inhibitors. Both were administered propofol-alfentanil anesthesia without complications.