Providing sedation and analgesia (PSA) to patients to accomplish painful procedures or difficult diagnostic imaging is becoming a standard practice in every emergency department (ED). Emergency physicians (EPs) are called upon daily to provide this service. Despite the emergence as a common procedure, PSA is as yet an evolving area of emergency medicine marked with tradition, unchallenged dogma, and unanswered questions. Heretofore we used the term "conscious sedation" to define the act of giving sedatives and analgesics to patients. This term has since been abandoned for a more precise and meaningful title. Conscious sedation implies an alert patient yet sedated. It is an oxymoron. In addition, it is an imprecise description of the patient. During this procedure patients experience a spectrum of sedation, most of which is not in the "conscious" zone. The term conscious sedation is not recognized by the Joint Commission on Accreditation of Health Care Organizations (JCAHO) as a measurable level of sedation, and has since been abandoned for a more inclusive yet flexible title, "procedural sedation and analgesia" [1]. In 2001, JCAHO created sedation guidelines in an attempt to define the spectrum of procedural sedation and analgesia and provide a qualitative measurement for EPs [2]. The spectrum ranges from minimal sedation to general anesthesia, with defined criteria at each level. Minimal sedation is equivalent to anxiolysis. It is a drug-induced state during which patients respond normally to verbal commands. Respiratory and cardiovascular functions are not affected [2]. Next in the spectrum is moderate sedation/analgesia. This describes a depression of consciousness during which patients respond purposefully to verbal commands, either alone or accompanied by light tactile stimulation. Spontaneous ventilation is adequate, and cardiovascular function is usually maintained [2]. The deeper levels of the spectrum range from "deep sedation" to "general anesthesia." Deep sedation/analgesia describes a depression of consciousness during which patients cannot be easily aroused but respond purposefully following repeated or painful stimuli. Patients may require assistance in maintaining a patent airway and spontaneous ventilation. Cardiovascular function is usually maintained [2]. General anesthesia is the point at which consciousness is lost and the patient is not rousable to stimuli. The patient requires respiratory assistance and cardiovascular function is often impaired [2]. Another level of sedation, which may be placed along with moderate sedation, is dissociative sedation. This is a relatively new description since the introduction of ketamine as a sedative agent. It is characterized as a trance-like cataleptic state induced by a dissociative agent that provides profound analgesia and amnesia. Protective airway reflexes and spontaneous respirations are maintained along with cardiovascular stability [2]. The JCAHO sedation guidelines provide qualitative goals for the EP when he/she is conducting PSA, The ideal is to fulfill all the goals of PSA, which are to alleviate anxiety. minimize physical pain and discomfort, and maximize amnesia. In addition, PSA Should assist in controlling behavior to expedite the procedure while minimizing negative psychologic responses to treatment. Last, the EP strives to maintain safety by minimizing risks and ensuring safe discharge. PSA continues to evolve within emergency medicine. This field of practice is becoming more defined. Clinical dogma is being challenged, resulting in new concepts and application to emergency medicine. Last, EPs are building experience with multiple drugs. which adds to Our armamentarium. By understanding the current and new concepts or PSA. becoming familiar with the pharmacologic agents. and appreciating the spectrum of sedation, the EP can reach his clinical goals.
