Effect of isolated anticonvulsant drug use and associated to midazolam as pre-anesthetic medication on the Bispectral Index (BIS) in patients with cerebral palsy.

BACKGROUND AND OBJECTIVES: Patients with cerebral palsy (CP) frequently receive drugs for the treatment of concomitant diseases, such as seizures. Midazolam is a benzodiazepine with hypnotic action most often used as pre-anesthetic medication and its drug interactions in patients with CP are unknown. The objective of the present study was to evaluate the effect of midazolam as pre-anesthetic drug on the BIS of patients with CP undergoing chronic treatment with anticonvulsant agents. METHOD: Three groups of patients were assessed: CP without anticonvulsant treatment, CP undergoing treatment with anticonvulsant and a group with no disease and no medication use (control group). On the day before the surgery, with the patients conscious and in dorsal decubitus, the BIS monitor was placed and the basal BIS values were recorded. On the following day, 40 minutes before the surgery, the patients received 0.6 mg*kg(-1) of midazolam orally. Before the start of the anesthetic procedure, the same procedure for BIS recording was carried out after midazolam administration. RESULTS: A total of 107 patients were studied - 39 patients from the Control Group (CG) and 68 with a diagnosis of CP. Among these, 17 used anticonvulsant drugs. Regarding the mean BIS value after the midazolam administration, there was no difference between patients from the CG and those in the CP group that did not take anticonvulsant drugs, whereas the ones who took anticonvulsants exhibited a difference (p = 0.003). The possibility of decrease in the BIS after midazolam use increases according to the number of anticonvulsant drugs used by the patient. CONCLUSIONS: The chronic use of anticonvulsants associated to oral midazolam as pre-anesthetic medication can lead to the decrease in the BIS values, which configures deep level of hypnosis.

Ação do anticonvulsivante isolado e associado ao midazolam como medicação pré-anestésica sobre o índice bispectral (BIS) em pacientes com paralisa cerebral / Effect of isolated anticonvulsant drug use and associated to midazolam as pre-anesthetic medication on the bispectral index (BIS) in patients with cerebral palsy

JUSTIFICATIVA E OBJETIVOS: Os pacientes com paralisia cerebral (PC) frequentemente usam fármacos para tratamento de doenças concomitantes, como convulsões. O midazolam é o hipnótico mais utilizado como medicação pré-anestésica e suas interações medicamentosas nos pacientes com PC são desconhecidas. O objetivo deste estudo foi avaliar o midazolam como medicação pré-anestésica no BIS dos pacientes com PC em uso crônico de anticonvulsivantes. MÉTODO: Foram avaliados três grupos de pacientes: PC sem uso de anticonvulsivantes, PC em uso de anticonvulsivante e outro grupo sem doença e sem uso de medicações (Grupo Controle). Na véspera da cirurgia, com os pacientes despertos e em decúbito dorsal, foi colocado o monitor do BIS e foram registrados os valores basais do BIS. No dia seguinte, 40 minutos antes da cirurgia, os pacientes receberam 0,6 mg.kg-1 de midazolam por via oral. Antes do início da anestesia, foi realizado o mesmo procedimento para registro do BIS, após o uso do midazolam. RESULTADOS: Foram estudados 107 pacientes - 39 pacientes do Grupo Controle e 68 com diagnóstico de PC. Desses, 17 faziam uso de anticonvulsivante. Com relação ao valor médio de BIS após o uso do midazolam, não houve diferença entres os pacientes do Grupo Controle e do Grupo PC que não tomavam anticonvulsivante, enquanto entre os pacientes que faziam uso de anticonvulsivantes houve diferença (p = 0,003). A possibilidade de diminuição do BIS após o uso do midazolam aumenta de acordo com o número de anticonvulsivantes usados pelo paciente. CONCLUSÕES: O uso crônico de anticonvulsivante associado ao midazolam via oral como medicação pré-anestésica pode levar à diminuição dos valores de BIS, configurando níveis profundos de hipnose.

BACKGROUND AND OBJECTIVES: Patients with cerebral palsy (CP) frequently receive drugs for the treatment of concomitant diseases, such as seizures. Midazolam is a benzodiazepine with hypnotic action most often used as pre-anesthetic medication and its drug interactions in patients with CP are unknown. The objective of the present study was to evaluate the effect of midazolam as pre-anesthetic drug on the BIS of patients with CP undergoing chronic treatment with anticonvulsant agents. METHOD: Three groups of patients were assessed: CP without anticonvulsant treatment, CP undergoing treatment with anticonvulsant and a group with no disease and no medication use (control group). On the day before the surgery, with the patients conscious and in dorsal decubitus, the BIS monitor was placed and the basal BIS values were recorded. On the following day, 40 minutes before the surgery, the patients received 0.6 mg.kg-1 of midazolam orally. Before the start of the anesthetic procedure, the same procedure for BIS recording was carried out after midazolam administration. RESULTS: A total of 107 patients were studied - 39 patients from the Control Group (CG) and 68 with a diagnosis of CP. Among these, 17 used anticonvulsant drugs. Regarding the mean BIS value after the midazolam administration, there was no difference between patients from the CG and those in the CP group that did not take anticonvulsant drugs, whereas the ones who took anticonvulsants exhibited a difference (p = 0.003). The possibility of decrease in the BIS after midazolam use increases according to the number of anticonvulsant drugs used by the patient. CONCLUSIONS: The chronic use of anticonvulsants associated to oral midazolam as pre-anesthetic medication can lead to the decrease in the BIS values, which configures deep level of hypnosis.

JUSTIFICATIVA Y OBJETIVOS: Los pacientes con parálisis cerebral (PC), a menudo usan fármacos para el tratamiento de enfermedades concomitantes, como las convulsiones. El midazolam es el hipnótico más utilizado como medicación preanestésica y no se conocen sus interacciones medicamentosas en los pacientes con PC. El objetivo de este estudio fue evaluar el midazolam como medicación preanestésica en el BIS de los pacientes con PC en uso crónico de antiepilépticos. MÉTODO: Se evaluaron tres grupos de pacientes: PC sin uso de antiepilépticos, PC en uso de antiepiléptico y otro grupo sin enfermedad y sin uso de medicaciones (grupo control). En la víspera de la cirugía, con los pacientes despiertos y en decúbito dorsal, fue colocado el monitor del BIS y se registraron los valores basales del BIS. Al día siguiente, 40 minutos antes de la cirugía, los pacientes recibieron 0,6 mg.kg-1 de midazolam por vía oral. Antes del inicio de la anestesia fue realizado el mismo procedimiento para registro del BIS, después del uso del midazolam. RESULTADOS: Fueron estudiados 107 pacientes, 39 pacientes del grupo control y 68 con diagnóstico de PC. De ellos, 17 usaban antiepilépticos. Con relación al valor promedio de BIS después del uso del midazolam, no hubo diferencia entres los pacientes del grupo control y del grupo PC que no tomaban antiepiléptico, mientras que los pacientes que usaban antiepilépticos fueron diferentes (p = 0,003). La posibilidad de disminución del BIS después del uso del midazolam, aumenta de acuerdo con el número de antiepiléptico usado por el paciente. CONCLUSIONES: El uso crónico de antiepiléptico asociado al midazolam vía oral como medicación preanestésica, puede conllevar a la disminución de los valores de BIS configurando niveles profundos de hipnosis.