Drug Choice for Procedural Sedation: Propofol vs. Ketamine

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Author: Randy Kring, MSIV
Tufts University School of Medicine

Procedural sedation is frequently performed in the emergency department, whether it is for electrical cardioversion, closed joint reduction or abscess incision and drainage. Although the focus in these cases is often on the procedure, smart preparation for procedural sedation and an understanding of the different strategies that can be used is vitally important.

The goal of procedural sedation is to provide moderate sedation and analgesia while preserving the patient’s protective airway reflexes, adequate ventilation and cardiovascular function. Relative contraindications for procedural sedation may include advanced age, significant medical comorbidities such as CHF or COPD or signs of a difficult airway.[1] Recent food intake is not a contraindication for procedural sedation, but aspiration risk should be assessed and minimized whenever possible.[2] Many drugs can be used for procedural sedation, including midazolam, etomidate, propofol and ketamine. Which drug is “the best?”

Propofol, a sedative and amnestic, has onset in about 40 seconds and duration of action of about six minutes. Common side effects include pain at the injection site, hypotension and respiratory depression.[3] Ketamine, a dissociative anesthetic that provides sedation, amnesia and analgesia, has onset in about 30 seconds and duration of action of about 10 to 20 minutes. Common side effects include agitation on emergence, nausea and (rarely) tachycardia and hypertension.[4]

Several studies have compared propofol and ketamine. One non-blinded randomized trial (n=97) found that compared with ketamine, propofol is associated with a shorter time to return to baseline mental status, and reduced agitation during recovery.[5] Another non-blinded randomized trial (n=60) found that patients sedated with a combination of ketamine and midazolam took longer to return to baseline mental status than patients sedated with propofol.[6]

Yet another option for procedural sedation is what has been dubbed “ketofol,” a 1:1 combination of ketamine and propofol. The theory behind this formulation is that using lower doses of each medication imparts fewer side effects while reaching the same level of sedation. However, studies of ketofol to date have not found it to be safer or more effective than propofol alone.[7]

References:

1. Frank RL. Procedural sedation in adults. UpToDate. Last updated July 2, 2014. http://www.uptodate.com/contents/procedural-sedation-in-adults.
2. Godwin SA, Caro DA, Wolf SJ, et al. Clinical policy: Procedural sedation and analgesia in the emergency department. Ann Emerg Med. 2005;45(2):177.
3. Miner JR, Burton JH. Clinical practice advisory: Emergency department procedural sedation with propofol. Ann Emerg Med. 2007;50(2):182.
4. Brown TB, Lovato LM, Parker D. Procedural sedation in the acute care setting. Am Fam Physician. 2005;71(1):85.
5. Miner JR, Gray RO, Bahr J, et al. Randomized clinical trial of propofol versus ketamine for procedural sedation in the emergency department. Acad Emerg Med. 2010;17(6):604.
6. Uri O, Behrbalk E, Haim A, et al. Procedural sedation with propofol for painful orthopaedic manipulation in the emergency department expedites patient management compared with a midazolam/ketamine regimen. Journal of Bone & Joint Surgery. 2011;93:2255-62.
7. David H, Shipp J. A randomized controlled trial of ketamine/propofol versus propofol alone for emergency department procedural sedation. Ann Emerg Med. 2011;57(5):435.