Following a drug overdose, the agitated delirious patient (in the ED or ICU) can be a difficult management problem. Naturally, you don’t want the patient to harm either him/herself or a health care provider (HCP). The easiest approach may seem to be endotracheal intubation. But what many HCP don’t see is how difficult it can be to extubate this same person that you so skillfully intubated. The patient is not intubated due to oxygen requirement or airway concern. So a completely awake agitated patient is paralyzed and ventilated, using vital signs (hypertension and tachycardia-although these may also be effects of the drugs) to determine the comfort of the patient.
Consider another approach-using drugs to obtain a state similar to conscious sedation. Intravenous midazolam is my favorite-starting at about 2 mg/hour and increase as needed. This is so much better than the intermittent administration of benzodiazepines. The benzo transiently puts the person to sleep who then may awaken with signs similar to an emergence reaction only to be put to sleep again and awaken in the same way. However, higher doses of the drug may be needed. (One ED could not do this because the dose required was greater than the hospital policy.) This past week, an agitated patient rested comfortably overnight on 8 mg/hour midazolam. As the midazolam was turned off, a small dose of precedex was administered. Of course, these patients should be monitored.
Dexemetomidate (Precedex) is the other consideration. It is an alpha-2 adrenergic agonist with sedation that is distinct from GABA (BZDP). It binds to imidazoline receptors and to alpha-1 receptors at high doses. It has a biphasic effect on blood pressure (BP) which increases during hi dose (loading) due to peripheral vasoconstriction and subsequently decreases due to central and peripheral sympatholytic effects. Heart rate is decreased even at low doses. There is minimal effect on respiration with rate and oxygen saturation remaining within normal limits.
Once a level of conscious sedation is achieved that is comfortable for the patient (and for you), let them rest!!! Wait at least 4 hours before you stop the drug. If the patient is still agitated and delirious, then repeat the conscious sedation for another 4-6 hours. Although rare, a central anticholinergic syndrome can last up to 3 days.