Brazilian Journal of Anesthesiology
http://www.rba.periodikos.com.br/article/doi/10.1590/S0034-70942002000100002
Brazilian Journal of Anesthesiology
Scientific Article

Níveis de sedação determinados pela clonidina e midazolam na medicação pré-anestésica: avaliação clínica e eletroencefalográfica bispectral

Sedation levels of oral preanesthetic clonidine and midazolam: clinical and electroencephalographic bispectral analysis

Leandro Gobbo Braz; Pedro Thadeu Galvão Vianna; José Reinaldo Cerqueira Braz; Maria Zoé Turchiari de Mello; Lídia Raquel de Carvalho

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Resumo

JUSTIFICATIVA E OBJETIVOS: Verificar o efeito sedativo da clonidina, um a2-agonista, e do midazolam, um benzodiazepínico, quando utilizados na medicação pré-anestésica, empregando-se avaliação clínica e eletroencefalográfica bispectral. MÉTODO: Após aprovação institucional e consentimento escrito fornecido, 45 pacientes de 18 a 65 anos, estado físico ASA I, foram aleatoriamente distribuídos nos grupos placebo (P), clonidina (C) ou midazolam (M), em que receberam, respectivamente placebo, 150 µg de clonidina ou 15 mg de midazolam por via oral, 60 minutos antes da indução da anestesia (n = 15 por grupo). A monitorização constituiu-se de eletrocardiograma (D II), pressão arterial não invasiva, freqüência cardíaca, saturação de pulso de oxigênio, freqüência respiratória, temperatura axilar e da sala de cirurgia e eletroencefalograma bispectral para determinação do índice bispectral (BIS). Esses atributos e a escala de sedações (1 - ansioso, 2 - calmo, 3 - sonolento, 4 - dormindo com reflexo, 5 - dormindo sem reflexo) foram obtidos aos 0 (M0), 15 (M15), 30 (M30), 40 (M40), 50 (M50) e 60 (M60) minutos após a medicação. RESULTADOS: Nos grupos não houve alteração significante dos parâmetros respiratórios, hemodinâmicos e de temperatura. Houve diferença significante entre os grupos na ES (M60: M=C>P) e no BIS (M50 e M60: M=C>P). CONCLUSÕES: Nas condições utilizadas, a clonidina e o midazolam determinaram níveis de sedação adequados e semelhantes na medicação pré-anestésica de pacientes estado físico ASA I, quando avaliados pela escala de sedação e pelo índice bispectral, sem determinarem alterações hemodinâmicas e respiratórias.

Palavras-chave

MEDICAÇÃO PRÉ-ANESTÉSICA, MEDICAÇÃO PRÉ-ANESTÉSICA, MONITORIZAÇÃO, MONITORIZAÇÃO, SEDAÇÃO

Abstract

BACKGROUND AND OBJECTIVES: This study aimed at evaluating clonidine - an a2-agonist - and midazolam - a benzodiazepine - sedative effects in preanesthetic medication by clinical and electroencephalographic analysis. METHODS: After institutional approval and their informed written consent, participated in this study 45 patients aged 18 to 65 years, physical status ASA I, who were randomly distributed in placebo (P), clonidine (C) or midazolam (M) groups. Patients were premedicated with oral placebo, 150 µg clonidine or 15 mg midazolam 60 minutes before anesthetic induction (n = 15 per group). Monitoring consisted of electrocardiogram (D II), non-invasive blood pressure, heart rate, oxygen saturation, respiratory rate, axillary and operating room temperature and bispectral electroencephalography to determine bispectral index (BIS). These attributes and sedation scale (1-anxious, 2-calm, 3-sleepy, 4-sleeping with reflex, 5-sleeping without reflex) were obtained at 0 (M0), 15 (M15), 30 (M30), 40 (M40), 50 (M50) and 60 (M60) minutes after medication. RESULTS: There were no significant differences in respiratory, hemodynamic and temperature parameters. There has been a significant difference among groups in sedation scale (M60: M=C>P) and BIS (M50 and M60: M=C>P). CONCLUSIONS: In our conditions, clonidine and midazolam have determined similar sedation levels in patients ASA I when evaluated by sedation scale and BIS. No hemodynamic and respiratory changes were observed with both drugs.

Keywords

MONITORING, MONITORING, PREANESTHETIC MEDICATION, PREANESTHETIC MEDICATION, SEDATION

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