Abstract
Objective: To compare isoflurane with midazolam for prolonged sedation in ventilated patients.Design: Randomised controlled study.Setting: General intensive care unit in university teaching hospital.Patients: Sixty patients aged 17–80 years who required mechanical ventilation for more than 24h.Interventions: Sedation with either 0.1–0.6% isoflurane in an air-oxygen mixture (30 patients) or a continuous infusion of midazolam 0.02–0.20 mg/kg/h (30 patients). Sedation was assessed initially and hourly thereafter on a six point scale. The trial sedative was stopped when the patient was ready for weaning from ventilatory support.Measurements and results: Measurements were made of haemodynamic, respiratory and biochemical variables regularly during the period of sedation and for a week after stopping the sedative agent. There was no difference in any of the physiological or biochemical variables recorded between the two groups. Patients sedated with isoflurane recovered more rapidly and were weaned from mechanical ventilation sooner than those sedated with midazolam.Conclusions: Isoflurane is a useful agent for prolonged sedation of ventilated patients and does not have any adverse effect on the cardiorespiratory system or on hepatic, renal or adrenal function.
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Aitkenhead AR, Pepperman ML, Willatts SM, Coates PD, Park GR, Bodenham AR, Collins CH, Smith MB, Ledingham IM, Wallace PGM (1989) Comparison of propofol and midazolam for sedation in critically ill patients. Lancet II:704–709
Newman LH, McDonald JC, Wallace PGM, Ledingham IMcA (1987) Propofol infusion for sedation in intensive care. Anaesthesia 42:929–937
Harris CE, Grounds RM, Murray AM, Lumley J, Royston D, Morgan M (1990) Propofol for long-term sedation in the intensive care unit. A comparison with papaveretum and midazolam. Anaesthesia 45:366–372
Eger EI II (1981) Isoflurane: a review. Anesthesiology 55:559–576
Kong KL, Willatts SM, Prys-Roberts C (1989) Isoflurane compared with midazolam for sedation in the intensive care unit. Br Med J 298:1277–1280
Knaus WA, Draper EA, Wagner DP, Zimmerman JE (1985) Apache II: a severity of disease classification system Crit Care Med 13:818–823
Ramsay MAE, Savage TM, Simpson BRJ, Goodwin A (1974) Controlled sedation with alphaxalone-alphadolone. Br Med J 2:656–659
Howie AF, Spencer EM, Beckett GJ (1992) Aspartate aminotransferase, alanine aminotransferase and glutathione transferase in plasma during and after sedation by low-dose isoflurane or midazolam. Clin Chem 38:476–479
Spencer EM, Willatts SM, Prys-Roberts C (1991) Plasma inorganic fluoride concentrations during and after prolonged (>24h) isoflurane sedation: effect on renal function. Anesth Analg 73:731–737
Blackett A, Dhillon S, Cromarty JA (1988) Rapid and sensitive high-performance liquid chromatographic assay for midazolam and 1-hydroxymidazolam, the major metabolite, in human serum. J Chromatogr 433:326–330
Toner W, Howard PJ, Scott MG, Black GW, Dundee JW (1979) Estination of blood enflurane concentrations by gas-liquid chromatography. Br J Anaesth 49:871–873
Truog RD, Rice SA (1989) Inorganic fluoride and prolonged isoflurane anesthesia in the intensive care unit. Anesth Analg 69:843–845
Smith RA, Winter PM, Smith M, Eger EI (1979) Tolerance to and dependence on inhalational anesthetics. Anesthesiology 50: 505–509
Oldenhof H, de Jong M, Steenhoek A, Janknegt R (1988) Clinical pharmacokinetics of midazolam in intensive care patients, a wide interpatient variability? Clin Pharmacol Ther 43:263–269
Frei FJ, Zbinden AM, Thomson DA, Rieder HU (1991) Is the endtidal partial pressure of isoflurane a good predictor of its arterial partial pressure? Br J Anaesth 66:331–339
McLeod DD, Ramayya GP, Tunstall ME (1985) Self-administered isoflurane in labour. A comparative with entonox. Anaesthesia 40:424–426
Hirschman CA, Edelstein G, Wayne R (1975) Attenuation of allergic bronchoconstriction by halothane and isoflurane. Anesthesiology 43:A386
Heneghan CPH, Bergman NA, Jordan C, Lehane JR, Catlay DM (1983) Effect of isoflurane on bronchomotor tone. Br J Anaesth 55:248–249
Revell S, Greenhalgh D, Absalom SR, Soni N (1988) Isoflurane in the treatment of asthma. Anaesthesia 1988:43:477–479
Bierman MI, Brown M, Muren O, Keenan RL, Glauser FL (1986) Prolonged isoflurane anesthesia in status asthmaticus. Crit Care Med 14:832–833
Hussey AJ, Aldridge LM, Paul D, Ray DC, Beckett GJ, Allan LG (1988) Plasma glutathione S-transferase concentration as a measure of hepatocellular integrity following a single general anaesthetic with halothane, enflurane or isoflurane. Br J Anaesth 60:130–135
Murray JM, Rowlands BJ, Trinick TR (1992) Indocyanine green clearance and hepatic function during and after prolonged anaesthesia: comparison of halothane with isoflurane Br J Anaesth 68:168–171
Kong KL, Willatts SM, Prys-Roberts C, Harvey JT, Gorman S (1990) Plasma catecholamine concentrations during sedation in ventilated patients requiring intensive therapy. Intensive Care Med 16:171–174
Spence AA (1987) Environmental pollution by inhalational anaesthetics. Br J Anaesth 59:96–103
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This study was supported by Abbott Laboratories Ltd, Abbott House, Moorbridge Road, Maidenhead SL6 8JG, Berks, UK
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Spencer, E.M., Willatts, S.M. Isoflurane for prolonged sedation in the intensive care unit; efficacy and safety. Intensive Care Med 18, 415–421 (1992). https://doi.org/10.1007/BF01694344
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DOI: https://doi.org/10.1007/BF01694344