Moderate sedation, also known as conscious sedation is an accepted method of providing sedation. Nurses in the OR, EDs, critical care units, radiology, endoscopy and bronchoscopy suites, labor and delivery settings, and outpatient offices administer sedative, opioid, and hypnotic medications to help patients through diagnostic, therapeutic, and minor surgical procedures.

To effectively and safely participate in the administration of IV moderate sedation, RNs must be able to differentiate the levels of sedation/analgesia; demonstrate competence with preprocedural, procedural, and postprocedural nursing care; anticipate and respond to patient emergencies during sedation; and understand the medical-legal aspects of sedation/analgesia.¹ The growing demand for moderate sedation services also requires RN participation in implementing educational programs, defining clinical competencies, monitoring standards, and ensuring adherence to prescribed levels of care which are addressed in professional and regulatory standards.

Defining the terms

The American Society of Anesthesiologists (ASA) in conjunction with TJC developed the following definitions for the various levels of sedation and anesthesia.^3,4

Minimal sedation (anxiolysis) is a drug-induced state in which a patient responds normally to verbal commands. The patient may have impaired cognitive function and coordination but cardiopulmonary functions are unaffected.

Moderate sedation/analgesia (“conscious sedation”) is a drug-induced depressed level of consciousness achieved with the administration of sedatives, hypnotics, and/or opioids. During this altered state of consciousness, the patient retains protective airway reflexes, independently and continuously maintains a patent airway and spontaneous ventilation, and can respond purposefully and appropriately to physical and verbal stimuli. Cardiovascular function is usually maintained.²

Deep sedation/analgesia is a drug-induced depression of consciousness during which a patient cannot be easily aroused but may respond purposefully after repeated painful stimulation. Reflex withdrawal from painful stimulus is not considered a purposeful response. Although cardiovascular function is usually stable, spontaneous ventilation can be impaired and the patient may require assistance to maintain a patent airway. Deep sedation can predispose patients to cardiopulmonary depression, delayed recovery, and unconsciousness.^2,3 General anesthesia is a drug-induced loss of consciousness, which renders the patient unarousable even with painful stimulation. The patient frequently requires an artificial airway, and positive pressure ventilation may be necessary; the risk for cardiovascular instability is increased.^2,3

These sedation states exist across a continuum and predicting how a patient may respond to the drugs administered may not be possible.^2,3 The patient may progress to a deeper level of sedation than intended requiring healthcare practitioners to support the patient while the depth of sedation is reversed to the desired level (“rescue”).

Since the patient’s response to procedures using moderate sedation techniques is not always predictable, it is imperative that only qualified people, credentialed and trained in professional standards and techniques, manage the care of patients undergoing moderate sedation.²

Sedative and analgesic medications are used for moderate sedation to achieve an altered state of consciousness with minimal risk, relief of anxiety, an amnesic state, and pain relief from noxious stimuli. Benzodiazepines, such as midazolam and diazepam, and opioids, such as morphine and fentanyl (Sublimaze), produce a minimally depressed level of consciousness, anxiolysis (a reduced anxiety level), and analgesia. In many cases, benzodiazepines are also capable of providing amnesia — the absence of awareness or recall of unpleasant stimuli and events. Amnesia is a desired, but not mandatory component of moderate sedation because lack of recall contributes to a positive experience for patients during diagnostic or therapeutic procedures. Opioids provide analgesia to decrease the normal pain response. Additional goals of moderate sedation include an altered mood state, enhanced patient cooperation, cardiovascular stability, and rapid return to preprocedure mental status.^3,4

Preprocedural phase

During preprocedure preparation, the provider assesses the patient and procedural risk factors, reduces anxiety through education, and generally ensures that the patient is in the best physical condition possible for the procedure. Optimal assessment occurs in a relaxed, unhurried atmosphere, and begins with a thorough review of the medical record, including past surgical and diagnostic procedures. Age, height, and weight are recorded. More important, patients are asked about previous reactions to anesthetics or sedatives, which alert the clinician to the possibility of nausea, vomiting, anaphylaxis, or post-procedural somnolence. Some patients may require a preprocedural antiemetic or a reduction in the dose of sedative medication.

During assessment, the nurse needs to look for —

• Cardiovascular problems, such as chest pain, hypertension, or exercise intolerance.
• A smoking history, the presence of chronic obstructive pulmonary disease, shortness of breath, or asthma that could lead to procedural hypoxia, hypercarbia, or hypoventilation.
• Renal or hepatic dysfunction that could affect the metabolism, elimination, and excretion of pharmacologic agents.
• Mental deficiency, cerebrovascular insufficiency, or intrinsic metabolic neurologic disease.
• Primary neurologic disease associated with over- and underproduction of hormones, such as hyper- or hypothyroidism or alterations in the stress response.^3,4

Of special interest to the nurse providing moderate sedation is an assessment of the patient’s airway. The patient should be able to open the mouth wide enough for use of an oral airway should it become necessary, flex the neck (capability of chin tilt for airway control), and have no craniofacial abnormalities that would preclude use of a bag/mask/valve device. Patients with a history of snoring or sleep apnea, advanced rheumatoid arthritis, a previous problem with anesthesia or sedation, or some chromosomal abnormalities are at risk for difficulty in airway management. An anesthesia provider should be consulted before sedation is administered

Patients with a history of diabetes should have their blood glucose level monitored frequently to identify tendencies toward hyper- or hypoglycemic states. The procedure should be scheduled as early as possible in the morning to permit time to obtain blood glucose levels, complete the procedure, and then administer the patient ’ s usual AM dose of insulin or oral hypoglycemic agent with nutrition. Morning doses are usually held until the patient is fully recovered. Nondextrose IV solutions, such as 0.9% or 0.45% normal saline, are used during the procedure.

A complete history of any prescribed or over-the-counter drugs or herbs should address why the patient is taking the drug, dosages, last dose taken, and efficacy of treatment. Accurate preprocedural instructions are important. For example, the continuation of antihypertensive medications up to and including the morning of the procedure may be necessary to maintain cardiovascular stability. Assessment of patients ’ allergy status is essential to avoid potential side effects of medications or the development of anaphylactic symptoms, such as edema, hives, pruritus, wheezing, bronchospasm, or circulatory collapse. Cross-sensitivity should also be considered. For example, a patient allergic to codeine may also have sensitivity to morphine; fentanyl should be used instead for sedation/analgesia.

The nurse should obtain a social history, including smoking, alcohol intake, illicit drug use, and the possibility of pregnancy. Patients with a smoking history may have hyperactive airways, which predispose them to laryngospasm, diminished oxygen saturation, coughing, and copious secretions during the procedure. Chronic alcohol abuse can predispose the patient to cirrhosis, elevated liver enzymes, esophageal varices, nutritional disorders, cardiac myopathy, benzodiazipine tolerance, and prolonged sedation recovery. History of long-term use of benzodiazepines and/or opioids may create a tolerance for these drugs,5 which influences the sedative and analgesic used for moderate sedation as well as the dosing and dosing intervals of the drugs.

Depending on the illicit drug used, more or less sedative medication may be necessary for example, long-term use of heroin or methadone will likely require the use of higher opioid doses to achieve effective sedation/analgesia.^5,6 Nurses need to question women of childbearing age about the possibility of pregnancy, because sedatives taken during the first trimester may cause fetal anomalies.⁷ Pregnant patients require consultation with the anesthesia team before diagnostic or minor surgical procedures.

Aspiration can occur during the administration of IV moderate sedation in patients who progress to deep sedation and lose protective airway reflexes. Aspiration of gastric contents can result in the development of anatomical, mechanical obstruction to gas flow, or chemical pneumonitis with severe ventilatory perfusion mismatch. Before receiving sedation, patients should take nothing by mouth (NPO), including solids or non-clear liquids for six to eight hours and no clear liquids for two to three hours for adults and children older than three years of age. Children between the ages of six and 36 months should have no solids or non-clear liquids for six hours, and no clear liquids for two to three hours. To avoid dehydration in children who are less than six months of age, solids or non-clear liquids four to six hours and clear liquids two hours before moderate sedation administration are permitted.³

The preprocedural assessment is completed with individualized patient instruction about NPO status, time of arrival, estimated procedure time, and any procedure-specific guidelines. Next the provider should be sure that an IV line can be established with a free flowing infusion, and that the following appropriately sized equipment and medications are on hand prior to administration of any sedative agent:^1,3,4,8

• Cardiac, blood pressure, and pulse oximetry monitors.
• Airway adjuncts, such as oral and nasopharyngeal airways, and endotracheal tubes and laryngoscope; bag valve mask device; oxygen source and delivery method such as a mask, and suction.
• Emergency cart with a defibrillator.
• Naloxone and flumazenil, opioid and benzodiazepine reversal drugs, respectively.

Other preprocedure requirements stipulated by The Joint Commission include:²

• Assessment of the patient ’ s anticipated postprocedure needs.
• Completion of preprocedural education, treatments, and services identified by the patient’s plan of care.
• Identification of the correct site, procedure, and patient is clearly communicated, using active communication techniques, during a final verification process such as a time-out immediately before starting the procedure.
• A preprocedure assessment is conducted immediately before sedating the patient.

Considerations during the procedure

Compliance with regulatory (e.g., TJC), statutory (e.g., Nurse Practice Acts), and professional (e.g., Guidelines for the Patient Receiving Moderate Sedation/ Analgesia, [Association of periOperative Registered Nurses])8 standards of care ensure patient safety and the avoidance of such complications as cardiovascular compromise, upper airway obstruction, and the development of hypoxia and hypercarbia. Monitoring during the procedure involves observation and vigilance, interpretation of data, and prompt initiation of required corrective actions. Providers monitor cardiac rate and rhythm, blood pressure, oxygen saturation, ventilatory status, and the patient’s level of consciousness.^1,3,4,8 Patients receiving moderate sedation routinely receive supplemental oxygen to reduce the incidence of hypoxia and arterial desaturation associated with some sedatives. However, supplemental oxygen does not assure that the patient is ventilated adequately and not retaining carbon dioxide. The patient ’ s ventilatory status must be monitored by audibly assessing ventilations with a precordial stethoscope or use of a capnograph that monitors end tidal CO₂.⁹

The Joint Commission mandates that in addition to the licensed independent practitioner performing the procedure, sufficient numbers of qualified staff need to be present to evaluate the patient, help with the procedure, provide the sedation, and monitor and recover the patient.² A qualified staff member should be dedicated solely to patient monitoring and safety. The hospital should define the qualifications of staff members involved with moderate sedation and ensure their continued competency.

RNs who participate in the administration of moderate sedation need to correlate patients’ symptoms with objective and subjective monitoring parameters to effectively assess, and intervene appropriately. Vital signs, recorded every five minutes on a flowsheet, provide a trend in cardiovascular and respiratory parameters. An assessment of the patient ’ s level of consciousness is particularly important to determine if a state of moderate sedation has been achieved, and if the patient has progressed to a deeper level of sedation than desired. At a minimum, a patient who is undergoing moderate sedation should be assessed and findings recorded before the procedure begins, after administration of a sedative/analgesic drug, at regular intervals throughout the procedure and during initial recovery, and just before discharge/transfer.^4,8 If monitoring equipment automatically records assessment, the device ’ s alarms should be set to alert the practitioners to changes in the patient ’ s status.

Pharmacologic techniques

Injected pharmacologic agents for moderate sedation ideally have a short duration of action, a lack of cumulative effects, rapid recovery, minimal side effects, and residual analgesia. Unfortunately, no single pharmacologic technique satisfies all requirements. To produce an amnesic, pain-free, sedated patient, a combination of sedative, hypnotic, and opioid medications is required. Through pharmacologic intervention, the patient ’ s perception of time is altered and cooperation is enhanced.¹⁰ Because moderate sedation occurs on a continuum, medication must be titrated to achieve a state of moderate sedation without moving the patient further on the continuum into deep sedation. The clinical endpoints of moderate sedation are nystagmus, slurred speech, and decreased patient anxiety. Unconsciousness, unresponsiveness, and deep sedation are not the objectives of moderate sedation, whose complications — hypoxia, hypercarbia, cardiopulmonary depression, and delayed recovery — rise proportionately as sedation deepens.

The simultaneous administration of benzodiazepines and opioids constitute the majority of moderate sedation techniques. The specific diagnostic or surgical procedure, patient population, or desired level of consciousness determine the choice of a variety of medication regimens.¹¹ Benzodiazepines, administered to achieve anxiolysis, sedation, and hypnosis, are the pharmacologic mainstay of moderate sedation. They bind to specific receptor sites in the central nervous system and readily cross the blood-brain barrier to exert their pharmacologic effect. Depending on the total amount of medication administered, benzodiazepines cause mild to deep sedation and in some cases, induce general anesthesia, which must be avoided in moderate sedation. Initially synthesized in 1959, diazepam is the prototypical benzodiazepine to which all others are compared.¹² This long-acting benzodiazepine is well-absorbed from the gastrointestinal tract and peak plasma levels are achieved in one to two hours after oral administration and one to two minutes after IV administration. Diazepam has a prolonged elimination half-life of 30 to 50 hours compared to its short-acting counterpart, midazolam, which has an elimination half-life of two to four hours.¹³ Diazepam’s propylene glycol suspension predisposes a patient to venous irritation and phlebitis and may cause a life-threatening hyperosmolar metabolic acidosis when the drug is administered in high doses to the elderly and patients with liver or renal disease.^5,14 On the other hand, midazolam is a water-soluble suspension. Although opioids produce some degree of sedation, they bind to specific opiate receptors located within the central nervous system to produce their primary effect, analgesia.

Naloxone is an opioid reversal agent that antagonizes the respiratory depressant effects associated with opioid administration. Reversal of respiratory depression may be achieved with as little as one to four mcg/kg body weight without full reversal of opioid analgesic effects. Titration of naloxone is recommended.¹² Flumazenil (Romazicon) is a benzodiazepine receptor antagonist that reverses the sedative effects associated with benzodiazepines. Reversal of the sedative effects of benzodiazepines may be achieved with 0.2 mg increments. Complications associated with reversal medications include nausea, vomiting, increased sympathetic nervous system activity, withdrawal symptoms, seizures, dysrhythmias, and death. Seizures have been reported with the use of flumazenil, particularly in patients on chronic benzodiazepine therapy. Withdrawal symptoms or severe rebound pain may occur when naloxone is administered to a patient who has used opioids for a prolonged period of time. The need for reversal agents can be avoided by administering incremental doses of the medications used to achieve the desired level of sedation/analgesia. However, specific reversal medications should always be immediately available in all areas where moderate sedation is administered.

Postprocedural phase

The postprocedural period provides a time to assess the patient, provide care, and treat complications associated with the administration of moderate sedation or the procedure. Patients may be monitored in the treatment area or transferred to a designated post-procedural recovery area, which should be physically conducive to the needs of the patient and caregiver. Recovery areas must be well lit and located in a central area with appropriate monitoring and emergency resuscitative equipment. Postprocedural monitoring provides for the return of the patient ’ s physiologic function before discharge or return to the inpatient setting. To prevent premature patient discharge, mechanisms must be in place to assess home readiness. Documentation before discharge is based on adherence to specific objective clinical parameters. Nurses participating in this phase of care must be prepared to provide emergent care in the event of an adverse reaction or cardiopulmonary compromise.

In addition to the postprocedure requirements mentioned above, TJC standards direct the following actions:²

• Assessment of the patient’s status immediately after the procedure
• Monitoring of the patient’s physiological and mental status, and pain level
• Monitoring of the patient at a level consistent with the potential effect of the procedure and/or sedation
• Discharge of the patient by a licensed independent practitioner or according to criteria approved by the medical staff
• Patient’s receiving sedation in the outpatient setting are discharged in the company of a responsible, designated adult

Legal issues and risk management

Many state boards of nursing have adopted formal positions or policy statements that delineate the responsibility of an RN engaged in the administration of moderate sedation. RNs must be aware of state-specific requirements associated with the clinical practice of moderate sedation, such as requirements for adult and pediatric cardiac life support course completion, monitoring, IV access, and post-procedural patient care. Each clinical site administering moderate sedation should maintain a current copy of their individual state board of nursing’s position or policy statement.⁴

Facilities that are accredited through The Joint Commission are also expected to adhere to written guidelines as outlined by that accrediting organization.² The Joint Commission standards apply to patients receiving general, spinal, and other major regional anesthesia, as well as sedation with or without analgesia, which, because of the manner in which it is used, may be reasonably expected to result in the loss of protective reflexes.² Because individual patient response to sedative medications cannot always be predicted, each institution should develop appropriate protocols for these patients. The Joint Commission mandates that protocols are consistent with professional standards that encompass qualified personnel, monitoring and emergency equipment, physiologic parameters to be monitored, documentation of patient care, and outcome measurement.³ Practice guidelines have also been published by the Association of periOperative Registered Nurses, the American Association of Nurse Anesthetists, American Nurses Association (endorsed by 23 Professional Nursing Organizations), ASA, the American Academy of Pediatrics, the Anesthesia Patient Safety Foundation, the American Society of PeriAnesthesia Nurses and other medical and specialty organizations.

The administration of moderate sedation for diagnostic or surgical procedures is a highly specialized skill. Clinicians must realize that the administration of sedative medications can easily produce a tranquil, amnesic patient or an unconscious, unresponsive patient. Failure to recognize an obstructed airway, hypoventilation, and cardiovascular depression continue to plague clinicians engaged in the administration of moderate sedation. However, educational preparation and clinical competency can minimize the risk. Appropriate guidelines may be achieved with thorough inservice training programs, the development of learning modules, and clinical preceptorships with qualified individuals familiar with the moderate sedation process.