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Sedative-analgesic medications in critically ill adults: Selection, initiation, maintenance, and withdrawal

Barry Fuchs, MD
Cassandra Bellamy, PharmD, BCPS
Section Editors
Polly E Parsons, MD
Michael Avidan, MD
Deputy Editor
Geraldine Finlay, MD


Distress generally presents as agitation. It is common among critically ill patients, especially those who are intubated or having difficulty communicating with their caregivers [1]. Distress needs to be treated for patient comfort and because it increases sympathetic tone, which may have untoward physiological effects [2]. Barring few exceptions (eg, neuromuscular paralysis, procedures) the administration of sedative-analgesic medications should not be based on anticipated distress but rather on that which is observed; otherwise, there will be an increased risk of over sedation which has been shown to worsen clinical outcomes.

The management of agitation in critically ill adults is reviewed here, including the initiation, maintenance, and withdrawal of pharmacological sedation. Common sedative-analgesic medications, the treatment of pain, and the use of neuromuscular blocking medications in critically ill patients are discussed elsewhere. (See "Sedative-analgesic medications in critically ill adults: Properties, dosage regimens, and adverse effects" and "Pain control in the critically ill adult patient" and "Use of neuromuscular blocking medications in critically ill patients".)


Before a sedative-analgesic agent is initiated to manage agitation, the cause of the distress should be identified and treated. Nonpharmacological strategies are preferred and should be implemented prior to the use of pharmacologic treatment.

Identify the cause of distress — Common causes of distress in critically ill patients include anxiety, pain, delirium, dyspnea, and neuromuscular paralysis. These etiologies may occur separately or in combination.

Anxiety – Anxiety is defined as a sustained state of apprehension and autonomic arousal in response to real or perceived threats [1]. Fear of suffering, fear of death, loss of control, and frustration due to the inability to effectively communicate are typical causes of anxiety in critically ill patients. Symptoms and signs include headache, nausea, insomnia, anorexia, dyspnea, palpitations, dizziness, dry mouth, chest pain, diaphoresis, hyperventilation, pallor, tachycardia, tremulousness, and/or hypervigilance.

Identifying and treating the proximate cause of anxiety is always ideal as it may ameliorate both problems. Dyspnea, for example, is a common underlying cause of anxiety among critically-ill patients. Thus, if inadequate ventilator flow is causing dyspnea with resultant anxiety, the ultimate treatment for the anxiety (and underlying dyspnea) may be adjustment of ventilator settings. Alternatively, the abrupt onset of anxiety may prompt further work-up for a cardiopulmonary source.


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Literature review current through: Sep 2016. | This topic last updated: Apr 15, 2016.
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