Choice of Analgesia and Sedation

Within the ABCDEF bundle, the C element, Choice of Analgesia and Sedation, focuses on constructing a safe and effective medication regimen for the management of pain and agitation in critically ill adults, consistent with ICU pain, agitation and delirium (PAD) Guidelines recommendations.

All ICU patients should be routinely assessed for pain using one of the following methods:

  • Patient self-report, which is most reliable
  • Numeric Rating Scale (NRS), such as the Likert Scale self-report
  • Behavioral Pain Scale (BPS) or Critical-Care Pain Assessment Tool (CPOT) non-self-reports

Pain and discomfort should be treated first before considering sedative therapy.

All ICU patients should be assessed routinely for agitation and depth of sedation with one of the following tools:

  • Richmond Agitation-Sedation Scale (RASS)
  • Riker Sedation-Agitation Scale (SAS)

All ICU patients should be assessed routinely for delirium with one of the following scales:

  • Confusion Assessment Method for the ICU (CAM-ICU)
  • Intensive Care Delirium Screening Checklist (ICDSC)

Properties of an ideal sedative include:

  • Rapid onset and rapid offset
  • Predictable dose-response relationship
  • Ease of administration
  • Lack of drug accumulation
  • Few side effects
  • Minimal drug interactions
  • Cost-effectiveness
  • Promotion of natural sleep

The interprofessional ICU team should reevaluate, at least daily, the appropriateness and the continued need for all pharmacologic interventions that have been initiated for treating pain and agitation.

Implementation Tools
Implementing the C component of the ABCDEF bundle.

Assessment Tools
Richmond-Agitation Sedation Scale
Sedation Agitation Scale





The PAD guidelines recommend that depth and quality of sedation should be routinely assessed in all ICU patients. The Richmond Agitation-Sedation Scale (RASS) and the Riker Sedation-Agitation Scale (SAS) are considered the most valid and reliable tools for assessing adequacy and depth of sedation in critically ill patients who are not receiving neuromuscular blocking agents.

Ideal Wakefulness
Moderate Sedation (3): movement or eye opening to voice, but no eye contact
Deep Sedation (4): no response to voice, but movement or eye opening
Unarousable (5): no response to voice or physical stimulation
2 to 0
Light Sedation (2): briefly awakens with eye contact to voice (<10 seconds)
Drowsy (1): not fully alert, but has sustained awakening (eye-opening / eye contact) to voice (< 10 seconds)
Alert and Calm (0)
  > 0
Restless (+1): anxious but movements not aggressive or vigorous
Agitated (+2): frequent non-purposeful movement, fights ventilator
Very Agitated (+3): pulls or removes tube(s) or catheter(s), aggressive
Combative (+4): overtly combative, violent, immediate danger to staff
< 3
Very Sedated (2): arouses to physical stimuli but does not communicate or follow commands, may move spontaneously
Unarousable (1): minimal or no response to noxious stimuli, does not communicate or follow commands
3 to 4
Sedated (3): difficult to arouse but awakens to verbal stimuli or gentle shaking, follows simple commands but drifts off again
Calm and Cooperative (4): calm, easily arousable, follows commands
> 4
Agitated (5): anxious or physically agitated, calms to verbal instructions
Very Agitated (6): requires restraint and frequent verbal reminders of limits, bites endotracheal tube
Dangerous Agitation (7): pulls at endotracheal tube, tries to remove catheter(s), climbs over bed rail, strikes at staff, thrashes side to side






Nonpharmacologic strategies play an important role in managing pain and agitation.

IV opioids should be considered first-line analgesics for the treatment of non-neuropathic pain. Nonopioid analgesics should be considered to decrease the amount of opioids administered and thereby to decrease opioid-induced adverse effects.

Optimize opioid regimens by assessing the following considerations:

  • Is pain acute, persistent, or both?
  • Route of administration
  • Hemodynamic instability


When treating agitation, it is important to titrate sedative medications to maintain lighter levels of sedation; deep sedation or coma should be avoided.


The PAD Guidelines suggest that, in adult ICU patients with delirium unrelated to alcohol or benzodiazepine withdrawal, continuous IV infusions of dexmedetomidine (rather than benzodiazepine infusions) be administered for sedation to reduce the duration of delirium. Also, atypical antipsychotics may reduce the duration of delirium in adult ICU patients. Treatment with rivastigmine or haloperidol does not reduce the duration of delirium.




Nonpharmacologic strategies play an important role when preventing and managing delirium.

Before administering a medication to either prevent or treat delirium in the ICU:

  1. Consider nonmedication-related, reversible factors for delirium (e.g., hypoxemia, infection, electrolyte abnormalities).
  2. If possible, stop (or decrease the dose of) any medication that may increase delirium risk.
  3. Mobilize patients when possible.
  4. Optimize nonpharmacologic interventions that may reduce delirium incidence and/or burden (e.g., hearing aids, eyeglasses, reorientation, sleep protocols, music, noise control, family interaction).



 Additional Reading


Carson SS, Kress JP, Rodgers JE, et al. A randomized trial of intermittent lorazepam versus propofol with daily interruption in mechanically ventilated patients. Crit Care Med. 2006 May;34(5):1326-1332.

Pandharipande P, Shintani A, Peterson J, et al. Lorazepam is an independent risk factor for transitioning to delirium in intensive care unit patients. Anesthesiology. 2006 Jan;104(1):21-26.

Pandharipande PP, Pun BT, Herr DL, et al. Effect of sedation with dexmedetomidine vs lorazepam on acute brain dysfunction in mechanically ventilated patients: the MENDS randomized controlled trial. JAMA. 2007 Dec;298(22):2644-2653.

Riker RR, Shehabi Y, Bokesch PM, et al. Dexmedetomidine vs midazolam for sedation of critically ill patients: a randomized trial. JAMA. 2009 Feb;301(5):489-499.

Treggiari MM, Romand JA, Yanez ND, et al. Randomized trial of light versus deep sedation on mental health after critical illness. Crit Care Med. 2009 Sep;37(9):2527-2534.

Pandharipande PP, Sanders RD, Girard TD, et al. Effect of dexmedetomidine versus lorazepam on outcome in patients with sepsis: an a priori-designed analysis of the MENDS randomized control trial. Crit Care. 2010;14(2):R38.

Strøm T, Martinussen T, Toft P. A protocol of no sedation for critically ill patients receiving mechanical ventilation: a randomised trial. Lancet. 2010 Feb;375(9713):475-480.

Needham DM, Korupolu R, Zanni JM, et al. Early physical medicine and rehabilitation for patients with acute respiratory failure: a quality improvement project. Arch Phys Med Rehabil. 2010 Apr;91(4):536-542.

Jakob SM, Ruokonen E, Grounds RM, et al. Dexmedetomidine vs midazolam or propofol for sedation during prolonged mechanical ventilation: two randomized controlled trials. JAMA. 2012 Mar 21;307(11):1151-1160.

Fraser GL, Devlin JW, Worby CP, et al. Benzodiazepine versus nonbenzodiazepine-based sedation for mechanically ventilated, critically ill adults: a systematic review and meta-analysis of randomized trials. Crit Care Med. 2013 Sep;41(9 suppl 1):S30-S38.

Dale CR, Kannas DA, Fan VS, et al. Improved analgesia, sedation, and delirium protocol associated with decreased duration of delirium and mechanical ventilation. Ann Am Thorac Soc. 2014 Mar;11(3):367-374.