Procedural sedation and analgesia (PSA) has been proven safe and efficacious within the emergency department (ED) environment, and should be utilized when patients undergo painful procedures. The most important step beyond close monitoring the patient involves extensive preparation. After the procedure, patients should return to their mental and physiologic baseline before disposition from the ED. In scenarios where the patient’s severity of illness questions the applicability of ED sedation, one must review the risks and consider consultation with an anesthesiologist. Although the degrees of sedation can at times be ambiguous, observing the patient’s progression and remaining vigilant for respiratory depression can diminish untoward effects and facilitate successful recovery and disposition.
BASICS OF PROCEDURAL SEDATION AND ANALGESIA
Sedation is often utilized to facilitate care in the ED. PSA has replaced the previous nomenclature of “conscious sedation.” The American College of Emergency Physicians (ACEP) defines PSA as the “administration of sedatives or dissociative agents with or without analgesics to induce a state that allows the patient to tolerate unpleasant procedures while maintaining cardiorespiratory function.”
The practitioner’s goal should be to avoid progressive unconsciousness and remain capable in managing their cardiopulmonary function when necessary. Despite concerns, the efficacy and safety of ED procedural sedations have been demonstrated in numerous studies, and PSA has become a core skill in emergency medicine training and practice.
PSA is a spectrum involving minimal, moderate, dissociative, deep, and general anesthesia levels necessitating the practitioner to be capable of recognizing the levels of sedation, and be prepared to rescue the next level of sedation if necessary. Each progressive degree of sedation increases the risk of cardiopulmonary instability with a likely need for aggressive intervention.
A drug-induced state during which patients respond normally to verbal commands. However, cognitive function and physical coordination both may be impaired, but the patient’s airway reflexes, ventilatory and cardiovascular functions are unaffected.
A drug-induced depression of consciousness during which the patient can respond purposefully to verbal commands, alone or verbal commands that are accompanied by lights tactile stimulation. Interventions to maintain the airway are required, and spontaneous ventilation is suitable. Cardiovascular function is routinely maintained.
A drug-induced trance-like cataleptic type state providing profound analgesia and amnesia, while maintaining the protective airway reflexes, spontaneous respirations, and cardiopulmonary stability. Ketamine is the most commonly administered agent in the ED to induce dissociative sedation.
A drug-induced depression of consciousness where patients cannot be easily aroused. However, the patient will respond purposefully subsequent to repeated painful stimulation. Reflex withdrawal from a painful stimulus is not considered a purposeful response. The ability to independently maintain ventilatory function may be impaired and patients may need assistance in maintaining a patent airway. In addition, spontaneous ventilation may be inadequate and rescue breaths may be required. Cardiovascular function is typically maintained.