Objectives: To analyze the dose of midazolam needed for induction and maintenance of sedation, as well as its hemodynamic repercussions in critically ill patients requiring mechanical ventilation.
Patients and methods: We studied 20 adult patients requiring mechanical ventilation for respiratory failure in the intensive care unit. An induction dose of 1 mg/min midazolam was given until the patient became drowsy (eyes closed but opened again) and this level of sedation was maintained by continuous intravenous perfusion. We calculated induction dose, maintenance dose and their correlation with age, weight, general state (APACHE-II index), liver function, hematocrit and blood chemistry.
Results: The induction dose was 4.76 +/- 3.4 mg and correlated with weight and plasma albumin levels. The maintenance dose of 6.4 +/- 3.97 mg/h did not correlate with any of the parameters studied. A statistically significant reduction in arterial pressure was observed.
Conclusions: The sedation dose of midazolam in critically ill patients is related to weight and plasma albumin levels. Recovery time is related to mean maintenance dose.