Sedation allows the depression of patients' awareness of the environment and reduction of their response to external stimulation. It plays a pivotal role in the care of the critically ill patient, and encompasses a wide spectrum of symptom control that will vary between patients, and among individuals throughout the course of their illnesses. Heavy sedation in critical care to facilitate endotracheal tube tolerance and ventilator synchronization, often with neuromuscular blocking agents, was routine until relatively recently. The modern ICU ventilator is equipped with a wide range of ventilatory modes and, with the addition of electronic flow triggering, synchronization problems have largely disappeared. The replacement of an endotracheal tube by a tracheostomy reduces the discomfort associated with an artificial airway and may often remove the need for sedation entirely. Thus, modern day sedation involves more than tube tolerance and is now focused on the multifactorial individual needs of the patient. Critical illness can be a frightening experience for a variety of reasons, and adequate sedation may reduce this. Study Objective: To determine the effects of oral clonidine premeditation sedative, anxiolytic, and hemodynamic responses during the immediate preoperative period, laryngoscopy/intubation, and postanesthetic recovery. Design: Randomized double-blind assignment to one of four treatment groups (clonidine 0.1 mg, clonidine 0.2 mg, triazolam 0.25 mg, or placebo); n = 10 per group. Setting: Inpatient surgery in a university-staffed tertiary center. Patients: Forty ASA physical status I and II adults of both sexes scheduled, for a variety of procedures requiring general anesthesia. Interventions: Anxiety and sedation scored on ordinal scale at time of treatment and 90 minutes later, just prior to anesthetic induction. Standardized induction protocol with automated hemodynamic monitoring at 1-minute intervals and a 45-second laryngoscopy to ensure a vigorous stress response. Measurements and Main Results: Triazolam and both closes of clonidine increased sedation at 90 minutes both absolutely and compared with a placebo.
Crit Care. 2017 Feb 25;21175. doi 10.1186/s13054-017-1610-8. Clonidine for sedation in the critically ill a systematic review and meta-analysis. Wang JG1. Apr 1, 2008. Sedation allows the depression of patients' awareness of the environment. Clonidine, Analgesia; anxiolysis; minimal respiratory depression.