Procedural sedation and analgesia

Procedural sedation and analgesia
Intervention
MeSH D016292
MedlinePlus 007409

Procedural sedation and analgesia, previously referred to as conscious sedation, is defined as "a technique of administering sedatives or dissociative agents with or without analgesics to induce a state that allows the patient to tolerate unpleasant procedures while maintaining cardiorespiratory function."[1]

Definitions

The American Society of Anesthesiologists defines the continuum of sedation as follows:[2]

Minimal Sedation Moderate Sedation Deep Sedation General Anesthesia
Responsiveness Normal to verbal stimulus Purposeful response to verbal or tactile stimulus Purposeful to repeated or painful stimulus Unarousable, even to painful stimulus
Airway Unaffected No intervention required Intervention may be required Intervention often required
Ventilation Unaffected Adequate May be inadequate Frequently inadequate
CardioVasc Function Unaffected Usually maintained Usually maintained May be impaired

Medical uses

This technique is often used in the emergency department for the performance of painful or uncomfortable procedures. Common purposes include:

Agents used

Sedatives/dissociative agents

Analgesics

Techniques

For most agents the person should have had nothing to eat for at least 6 hours. Clear fluids can be allowed up to two hours before the procedure. An exception to this may be with ketamine in children where fasting may be unnecessary. However, in the emergency room setting, conscious sedation is usually administered without waiting the full 6 hours unless there is clear evidence that the patient may not be able to maintain his/her airway on their own. The most common drug combination used is Versed (midazolam) for sedation (due to its potency and its ability to induce temporary amnesia, which can be beneficial because the unpleasantness of the procedure and any related sights, sounds, or smells) and Fentanyl for analgesia. Despite this being the most frequently used drug combination, variations are not uncommon due to factors such as patient allergies or clinician preference.[6]

Complications

Complications depend on the sedative agent that is used. Many commonly used agents can cause respiratory depression, hypoxia and hemodynamic effects. For some agents antagonists are available that can be used to reverse the effects.

Safety

Procedural sedation can be safely performed in an emergency department if structured sedation protocols are followed.[7]

Electrocardiography, pulse oximetry, capnography and blood pressure monitoring are essential, as is the use of supplementary oxygen.

Controversies

Some resistance to sedation techniques used outside the operating room by non-anesthetists has been voiced.[8]

History

Procedural sedation used to be referred to as conscious sedation.

References

  1. Procedural Sedation at eMedicine
  2. "Continuum of Depth of Sedation; Definition of General Anesthesia and Levels of Sedation/Analgesia". American Society of Anesthesiologists (ASA). 2009.
  3. "Procedural Sedation for Cardioversion".
  4. 4.0 4.1 Hohl, CM.; Sadatsafavi, M.; Nosyk, B.; Anis, AH. (January 2008). "Safety and clinical effectiveness of midazolam versus propofol for procedural sedation in the emergency department: a systematic review.". Acad Emerg Med 15 (1): 1–8. doi:10.1111/j.1553-2712.2007.00022.x. PMID 18211306.
  5. Messenger DW, Murray HE, Dungey PE, van Vlymen J, Sivilotti ML (October 2008). "Subdissociative-dose ketamine versus fentanyl for analgesia during propofol procedural sedation: a randomized clinical trial". Acad Emerg Med 15 (10): 877–86. doi:10.1111/j.1553-2712.2008.00219.x. PMID 18754820.
  6. "BestBets: Does the time of fasting affect complication rates during ketamine sedation".
  7. Ip U, Saincher A (January 2000). "Safety of pediatric procedural sedation in a Canadian emergency department". CJEM 2 (1): 15–20. PMID 17637112.
  8. Krauss B, Green SM (March 2006). "Procedural sedation and analgesia in children". Lancet 367 (9512): 766–80. doi:10.1016/S0140-6736(06)68230-5. PMID 16517277.

External links