Can pentobarbital replace amobarbital in the Wada test?

doi:10.1016/j.yebeh.2007.05.010

Epilepsy & Behavior

Volume 11, Issue 3, November 2007, Pages 378-383

https://doi.org/10.1016/j.yebeh.2007.05.010 Get rights and content

Abstract

To investigate the usefulness of pentobarbital (PTB) in the Wada test, 32 patients injected with PTB and 28 patients injected with amobarbital (AMB) were retrospectively analyzed. The AMB and PTB groups did not significantly differ with respect to mean time for recovery to grade III or V motor activity and duration of EEG delta slowing. The incidence of drowsiness or confusion after injection was lower in the PTB group (P = 0.043). Language lateralization was well established in both groups. Fifty-three percent of patients in the PTB group and 46.2% in the AMB group with unilateral temporal lobe epilepsy had memory dominance in the nonepileptic hemisphere. The usefulness of PTB in terms of language and memory lateralization was found to be equivalent to that of AMB. Moreover, PTB produced drowsiness and confusion less frequently than AMB, although one patient in the PTB group experienced transient respiratory depression without any sequelae.

Introduction

The Wada test has been a gold standard for language and memory lateralization since it was first described [1], [2].

To prevent postoperative memory and language deficit, especially in patients with temporal lobe epilepsy (TLE), language lateralization and determination of memory dominance are very important aspects of surgery planning. Most epilepsy centers use an intracarotid amobarbital injection for the Wada test. However, the continuation of this procedure has been recently challenged because of the recent interruption in the supply of amobarbital and the development of alternative tools [3], [4], [5]. Some centers in France and the United States use sodium methohexital (brevital) instead of sodium amobarbital [6], [7], [8].

Methohexital is a rapid, ultrashort-acting barbiturate anesthetic. Its duration of action is short, and it does not concentrate in body fat to the extent that other barbiturate anesthetics do. Nevertheless, it may elicit seizures in susceptible patients [9], [10], [11]. Moreover, its very short duration of action requires two injections during the Wada test [6].

On the other hand, sodium pentobarbital (PTB) is a short-acting barbiturate, and its duration of action is longer than that of thiopental or methohexital, though shorter than that of amobarbital. Furthermore, PTB has no reported risk of provoking seizures.

Because sodium amobarbital (AMB) supplied by Lilly has not been available in Korea since 2003, we started using PTB as an alternative anesthetic for the Wada test. Here, we report our experience with the Wada test using PTB and compare our results with those for AMB.

Section snippets

Patient information

Sixty consecutive patients with TLE were recruited from March 2003 to May 2004 in Samsung Medical Center and underwent the Wada test with either AMB or PTB for presurgical evaluation. Fifty patients had unilateral mesial TLE, seven unilateral lateral TLE, and three bilateral mesial TLE. We retrospectively analyzed the clinical information and Wada test results of both groups.

Twenty-eight patients received an intracarotid AMB injection for the Wada test (male 18, female 10; mean age 28.6 ± 11.3,

Results

Twenty-eight patients received an intracarotid AMB injection, and 32 patients, a PTB injection. No significant differences in clinical variables (i.e., age, epileptic syndrome, epileptic side, and handedness) were observed between the AMB and PTB groups (Table 1).

The mean AMB doses injected were 82.7 ± 15.4 and 85.6 ± 18.9 mg for right and left hemisphere anesthesia, respectively. The mean PTB doses injected were 25 ± 5.2 and 28.1 ± 8.4 mg for right and left hemisphere anesthesia. Right–left hemisphere

Discussion

Our study demonstrates that the Wada test using PTB can lateralize a language hemisphere as well as the test using AMB. Memory dominance was also well determined using PTB or AMB. The AMB and PTB groups did not significantly differ with respect to duration of EEG delta slowing and motor recovery time, although mean duration of EEG whole slowing was longer in the PTB group. EEG slowing is not always correlated with behavioral changes because anesthetics have different effects on different brain

Acknowledgments

This work was supported by a grant (A050462) of the Good Health R&D Project, Ministry of Health and Welfare, Republic of Korea, and by a grant (M103KV010016-07K2201-01610) from the Brain Research Center of the 21st Century Frontier Research Program funded by the Ministry of Science and Technology of the Republic of Korea, and by the Samsung Medical Center Clinical Research Development Program Grant, #CRS106-55-2.

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View full text

Can pentobarbital replace amobarbital in the Wada test?

Abstract

Introduction

Section snippets

Patient information

Results

Discussion

Acknowledgments

Brain Cogn

Epilepsy Behav

Neuropsychologia

Epilepsy Behav

A new method for the determination of the side of cerebral speech dominance: a preliminary report on the intracarotid injection of sodium amytal in man

Igaku Seibutugaku (Med Biol)

Has amobarbital expired? Considering the future of the Wada

Neurology

Functional MRI predicts memory performance after right mesiotemporal epilepsy surgery

Epilepsia

Alternatives to the Wada test: a critical view of functional magnetic resonance imaging in preoperative use

Curr Opin Neurol

Sodium methohexital (brevital) as an anesthetic in the Wada test

Epilepsia

Clinical and electroencephalographic manifestations during the Wada test using intracarotid injection of methohexital (Brietal)

Rev Neurol (Paris)

Identification of speech lateralization by intracarotid injection of methohexital

Ann Neurol

Seizures induced by methohexital

Anesthesiology