Brazilian Journal of Anesthesiology
https://bjan-sba.org/journal/rba/article/doi/10.1016/j.bjane.2013.07.015
Brazilian Journal of Anesthesiology
Scientific Article

Comparative study between fast and slow induction of propofol given by target-controlled infusion: expected propofol concentration at the effect site. Randomized controlled trial

Estudo comparativo entre indução rápida e lenta de propofol em infusão alvo-controlada: concentração de propofol prevista no local de ação. Ensaio clínico aleatório

Ricardo Francisco Simoni; Luiz Eduardo de Paula Gomes Miziara; Luis Otávio Esteves; Diógenes de Oliveira Silva; Cristina Alves Ribeiro; Mariana Oki Smith; Leonardo Ferreira de Paula; Luis Henrique Cangiani

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Abstract

BACKGROUND AND OBJECTIVE: Studies have shown that the rate of propofol infusion may influence the predicted propofol concentration at the effect site (Es). The aim of this study was to evaluate the Es predicted by the Marsh pharmacokinetic model (ke0 0.26 min-1) in loss of consciousness during fast or slow induction. METHOD: The study included 28 patients randomly divided into two equal groups. In slow induction group (S), target-controlled infusion (TCI) of propofol with plasma, Marsh pharmacokinetic model (ke0 0.26 min-1) with target concentration (Tc) at 2.0-µg mL-1 were administered. When the predicted propofol concentration at the effect site (Es) reached half of Es value, Es was increased to previous Es + 1 µg mL-1, successively, until loss of consciousness. In rapid induction group (R), patients were induced with TCI of propofol with plasma (6.0 µg mL-1) at effect site, and waited until loss of consciousness. RESULTS: In rapid induction group, Tc for loss of consciousness was significantly lower compared to slow induction group (1.67 ± 0.76 and 2.50 ± 0.56 µg mL-1, respectively, p = 0.004). CONCLUSION: The predicted propofol concentration at the effect site for loss of consciousness is different for rapid induction and slow induction, even with the same pharmacokinetic model of propofol and the same balance constant between plasma and effect site.

Keywords

Anesthetics, Intravenous, Propofol, Pharmacology, Anesthetic techniques, General, Intravenous

Resumo

JUSTIFICATIVA E OBJETIVO: estudos mostraram que a taxa de infusão de propofol pode influenciar na concentração prevista de propofol no local de ação (Ce). O objetivo deste estudo foi avaliar a Ce prevista pelo modelo farmacocinético de Marsh (ke0 0,26 min-1) na perda da consciência durante indução rápida ou lenta. MÉTODO: participaram deste estudo 28 pacientes, divididos aleatoriamente em dois grupos iguais. No grupo indução lenta (L), foram induzidos com propofol em infusão alvo-controlada (IAC) plasmática, modelo farmacocinético de Marsh (ke0 0,26 min-1), com concentração alvo (Ca) em 2,0 µg.ml-1. Quando a concentração de propofol prevista no local de ação (Ce) atingia metade do valor da Ca, aumentava-se a Ca para Ca anterior + 1 µg.ml-1. Assim sucessivamente até o momento da perda da consciência do paciente. No grupo indução rápida (R), os pacientes foram induzidos com propofol em IAC plasmática com Ca em 6,0 µg.ml-1 e aguardava-se a perda da consciência do paciente. RESULTADOS: no grupo indução rápida, a Ce na perda da consciência foi significativamente mais baixa em relação ao grupo de indução lenta (1,67 ± 0,76 e 2,50 ± 0,56 µg.ml-1, respectivamente, p = 0,004). CONCLUSÃO: a concentração prevista de propofol no local de ação durante a perda da consciência é diferente numa indução rápida e numa indução lenta, até com o mesmo modelo farmacocinético de propofol e a mesma constante de equilíbrio entre o plasma e o local de ação.

Palavras-chave

Anestésicos, Venoso, Propofol, Farmacologia, Técnicas anestésicas, Geral, Venosa

References

Gajraj RJ, Doi M, Mantzaridis H. Comparison of bispectral EEG analysis and auditory evoked potentials for monitoring depth of anaesthesia during propofol anaesthesia. Br J Anaesth.. 1999;82:672-8.

Barakat AR, Sutcliffe N, Schwab M. Effect site concentration during propofol TCI sedation: a comparison of sedation score with two pharmacokinetic models. Anaesthesia.. 2007;62:661-6.

Iwakiri H, Nishihara N, Nagata O. Individual effect-site concentrations of propofol are similar at loss of consciousness and at awakening. Anesth Analg.. 2005;100:107-10.

Simoni RF, Esteves LO, Miziara LEPG. Avaliação clínica de duas ke0 no mesmo modelo farmacocinético de propofol: estudo da perda e recuperação da consciência. Rev Bras Anestesiol.. 2011;61:397-408.

Iannuzzi M, Iannuzzi E, Rossi F. Relationship between bispectral index, electroencephalografic state entropy, and effect-site EC50 for propofol at different clinical endpoints. Br J Anaesth.. 2005;94:613-6.

Lysakowsky C, Elia N, Czarnetzki C. Bispectral and spectral entropy indices at propofol-induced loss of consciousness in young and elderly patients. Br J Anaesth.. 2009;103:387-93.

Struys MMRF, Coppens MJ, Neve ND. Influence of administration rate on propofol plasma-effect site equilibration. Anesthesiology.. 2007;107:386-96.

Sepulveda PO, Cortinez LI, Recart A. Predictive ability of propofol effect-site concentrations during fast and slow infusion rates. Acta Anaesthesiol Scand.. 2010;54:447-52.

Schnider TW, Minto CF, Shafer SL. The influence of age in propofol pharmacodynamics. Anesthesiology.. 1999;90:1502-16.

Kasama T, Morita K, Ikeda T. Comparison of predicted induction dose with predetermined physiologic characteristics of patients and with pharmacokinetic models incorporating those characteristics as covariates. Anesthesiology.. 2003;98:299-305.

Schuttler J, Ihmsen H. Population pharmacokinetics of propofol: a multicenter study. Anesthesiology.. 2000;92:727-38.

Krejcie TC, Henthorn TK, Niemann CU. Recirculatory pharmacokinetics models of makers of blood, extracellular fluid and total body water administered concomitantly. J Pharmacol Exp Ther.. 1996;278:1050-7.

Upton RN, Grant C, Martinez AM. Recirculatory model of fentanyl disposition with the brain as the target organ. Br J Anaesth.. 2004;93:687-97.

Avram MJ, Krejcie TC. Using front-end kinetics to optimize target-controlled drug infusion. Anesthesiology.. 2003;99:1078-86.

Henthorn TK, Krejcie TC, Avram MJ. Early drug distribution: a generally neglected aspect of pharmacokinetics of particular relevance to intravenously administered anesthesic agents. Clin Pharmacol Ther.. 2008;84:18-22.

Ludbrook GL, Visco E, Lam AM. Propofol: relation between brain concentrations, electroencephalogram, middle cerebral artery blood flow velocity, and cerebral oxygen extraction during induction of anesthesia. Anesthesiology.. 2002;97:1363-70.

Schwilden H, Stoeckel H, Schuttler J. Closed-loop feedback control of propofol anaesthesia by quantitative EEG analysis in humans. Br J Anaesth.. 1989;62:290-6.

Billard V, Gambus PL, Chamoun N. A comparison of spectral edge, delta power, and bispectral index as EEG measures of alfentanil, propofol, and midazolam drug effect. Clin Pharmacol Ther.. 1997;61:45-58.

White M, Schenkels MJ, Engbers FH. Effect-site modelling of propofol using auditory evoked potentials. Br J Anaesth.. 1999;82:333-9.

Masui K, Kira M, Kasama T. Early phase pharmacokinetics but not pharmacodynamics are influenced by propofol infusuion rate. Anesthesiology.. 2009;111:805-17.

Doufas AG, Bakhshandeh M, Bjorksten AR. Induction speed is not a determinant of propofol pharmacodynamics. Anesthesiology.. 2004;101:1112-21.

White M, Kenny GNC, Schraag S. Use of target controlled infusion to derive age and gender covariates for propofol clearance. Clin J Pharmacokinet.. 2008;47:119-27.

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