Moderate Sedation In-Service Training Web Course Credits Developed by The Employee Education System in conjunction with the VHA National Anesthesia Service(Patient Care Services), Michael J Bishop, MD, Director LEAD AUTHOR:Vadim Vornik, MD, Department of Anesthesiology, North Texas VA MODERATE SEDATION WORKGROUP MEMBERS: • Beverly O’Connor-Griffin, CRNA, Bay Pines VA • Susan T Brooks, RN, Baltimore VA • Grace Chien, MD, Portland VAMC • Kent Yucel, MD, Boston VA Health Care System • Sean Kennedy, MD, (Anesthesiology Field Advisory Committee), Philadelphia VA • Susan Valley, MD, (Anesthesiology Field Advisory Committee), Northern California VA HCS • Jonathan Mark, MD, (Anesthesiology Field Advisory Committee)Durham VA • Douglas Rotte, (Central Office Anesthesiology Health Systems Specialist) EES PROJECT TEAM: Richard Lussier, DR. P. H. - Program Manager, Employee Education SystemBeau Chandler - Program Specialist, Employee Education SystemDarea Chappelle - Program Specialist, Employee Education SystemRussell Bennett, MBA - Media Producer, Employee Education System
General Information • Privileges may be granted to a licensed independent practitioner to perform procedures under moderate sedation. Such privileges are not required when monitored anesthesia care is provided by an anesthesia provider. • Moderate sedation training or evidence of ongoing competency is required at the time of re-privileging. • Evidence of mastery of the content of this course or equivalent training is required for nursing personnel who assist with administration of sedation and monitoring.
Course Summary • This course consists of eight parts: • Definitions, Objectives, Standards, Guidelines • Pre-sedation Assessment • Sedation Pharmacology • Monitoring and Documentation • Airway Management • Complications of Sedation • Post-sedation Patient care • Sedation of the Geriatric Patient • Each part will require about 10-15 min to complete • At the end of the course the final exam will be conducted. You are required to have at least 75% correct answers in order to get full credit. Good Luck!!
JCAHO Standards Overview • New JCAHO Sedation/Analgesia Standards became effective in January 2004. • The JCAHO Standards for sedation and anesthesia apply when patients receive, in any setting for any purpose, by any route, moderate or deep sedation as well as general, spinal, or other major regional anesthesia. • These standards DO NOT apply to patients receiving minimal sedation (anxiolysis).
The VA Moderate Sedation Directive • Strict adherence to the JCAHO sedation standards • Adequate training of all individuals administering, monitoring, and or supervising moderate sedation with mandatory supervisory CPR competence
The Goals of Moderate Sedation/Analgesia • Providing a comfortable and cooperative patient • Elevation of pain threshold • Rapid recovery
Objectives of Moderate Sedation • Maintain adequate sedation with minimal risk • The patient’s ability to communicate should be preserved. Monitoring must be employed. Emergency resuscitation must always be on hand. • Relieve anxiety and produce amnesia when desired • These objectives are accomplished by means of good preoperative communication and instructions as well as administration of anxiolitic drugs. • Provide relief from pain and other noxious stimuli • Opioids are given to supplement local or topical anesthetics as needed.
Levels of Sedation & Analgesia Sedation and analgesia is a continuum and consist of the following states: * Reflex withdrawal from a painful stimulus is NOT considered a purposeful response
Definitions • Because it is not always possible to predict how each patient will respond to sedative and/or analgesic medications, practitioners intending to produce a given level of sedation should be able to rescue patients whose level of sedation becomes deeper than initially intended! e.g.: The practitioner who provides moderate sedation must be able to manage a compromised airway or hypoventilation in a patient who cannot be easily aroused, but responds purposefully following repeated or painful stimulation (deep sedation/ analgesia).
The Goals of Pre-Sedation Patient Assessment • Identify pre-sedation risk factors • Determine if any pre-sedation investigations or specialty consultations are required • Optimize the patient’s condition prior to the procedure • Review available documentation related to previous sedation/analgesia • Formulate a sedation plan • Obtain informed consent • Reduce patient’s anxiety through education and communication
Conducting the Pre-Procedure Assessment • The assessment is best conducted by the provider who will participate in the administration of sedation. If it is not possible, a different qualified staff member can perform the pre-procedure evaluation. In any case, an LIP must either complete or sign off on the assessment prior to the start of the case and/or administration of sedation. • When possible, pre-sedation assessment should be conducted several days prior to the proposed procedure to allow sufficient time for the collection of consults and laboratory results. • The pre-sedation assessment must be completed before the administration of any sedative agent. A set of vital signs must be documented prior to giving any sedatives. On the basis of the collected information a sedation plan should be developed and clearly documented in the chart. • The patient must be reassessed again immediately prior to the procedure. Any interval changes must be documented in the chart and addressed if necessary.
Components of the Pre-Sedation Evaluation • Documentation of relevant past medical history • Focused physical examination • Collecting relevant specialists’ consultations and tests
Collecting the Past Medical History (PMH) • At least the following information should be collected: • Height and weight (obesity, malnourishment) • Major organ systems abnormalities and evaluation of the airway • History of any previous adverse experiences with sedation/analgesia as well as regional and general anesthesia • Drug allergies and current medications • Tobacco, alcohol or substance use or abuse • Time and nature of last oral intake • An assessment of risk such as the American Society of Anesthesiologists Physical Status
Obesity and Moderate Sedation • Morbidly obese patients undergoing sedation are under significantly higher risk of complications than non-obese patients with otherwise similar medical problems • The negative effect on organs and systems is directly related to the degree of obesity with minimal changes in overweight patients (BMI=25-29kg/m2) and maximal impact on morbidly obese patients (BMI above 35kg/m2)* • Obese patients have a high prevalence of obstructive apnea and desaturate quickly. In general no sedative drugs should be administered before all the monitors have been applied and airway equipment is readily available • Obese patients are prone to pulmonary aspiration secondary to decreased gastric motility, increased gastric volume and intra-gastric pressure. Pre-medication with antacids, gastric stimulants and H2-blockers may be needed prior to administering sedation *Body Mass Index (BMI) = Weight (kg) / Height2 (M)
Pharmacokinetics and Pharmacodynamics in Obesity • In obese patients lipophilic drugs (benzodiaiepines, opioids) may demonstrate longer elimination half-life. In addition the sensitivity to the sedative drugs is unpredictable in this population • To minimize the development of deep sedation states, dosage requirements for sedative medications should be basedon ideal body weight and NOT the patient’s actual weight • If obstructive sleep apnea is suspected further decrease in dosage of sedative medications (as much as 50% to 70%) may be needed In general when dealing with obese patients titration to clinical effect is the safest approach to avoid oversedation
Sleep Apnea and Moderate Sedation • Sleep apnea is cessation of air flow for longer than 10 sec during sleep leading to arterial hypoxemia and hypercarbia. • If sleep apnea is suspected, pre-sedation assessment should include questioning about associated signs and symptoms such as morning headaches, overwhelming somnolence during normal waking hours, loss of initiative, memory problems, etc. • Institution of CPAP immediately after the procedure results in significantly fewer desaturation episodes. Ask those patients who use CPAP at home to bring their personal CPAP machines when coming for the procedures. This approach helps to avoid delays with the delivery of CPAP machines to numerous sleep apnea patients coming to the hospital. • Since sleep apnea patients are at increased risk for developing hypoxemia after the procedure, they should receive written discharge instructions to avoid taking any CNS depressants or consuming alcohol in the immediate post-procedure period. In some cases 24-hrs in-house observation may be considered.
PMH: Malnourished Patients • Patients with nutritional disorders, carcinoma, recent weight loss, advanced renal and liver diseases may experience an exaggerated effect from sedatives and analgesics as a result of the CNS hypersensitivity to drugs and decreased plasma protein binding ability. • Titration of pharmacologic agents is advised in such situations by administration of small incremental doses slowly over several minutes while continuously assessing the patient’s condition.
PMH: Major Organ System Diseases Evaluation should focus on the following: • Assessment for disease severity, stability and any recent changes in the patient’s condition • Assessment for prior and ongoing treatment and determining the time of the last dose of medication • Determining the variables that may affect the patient’s sensitivity to sedative drugs, predispose to airway compromise or/and cardio-pulmonary instability
PMH: Previous Complications with Anesthesia Review any old anesthesia or sedation flow sheets focusing on: • airway management • reaction to the medication • family history of complications related to anesthesia
PMH: Current medications Review the patient’s list of current medications focusing on the drugs that might: • affect pharmacokinetics or/and pharmacodynamics of the sedatives (e.g.: MAO inhibitors + meperidine hypertension, hyperpyrexia, coma) • cause hemodynamic or respiratory compromise in combination with sedatives (e.g.: ACE inhibitors + sedatives exaggerated hypotension)
PMH: Alcohol Abuse • In addition to multisystem disease state, chronic alcohol consumption leads to cross-tolerance to sedatives/analgesics. • Patients who seem to be acutely intoxicated are generally not good candidates for sedation because it suggests they are not NPO and also may not be able to follow post-procedure directives. In such patients, the urgency of the procedure should be weighed against the potentially increased risk.
PMH: Stimulant Abuse • Cocaine – is a potent vasoconstrictor and has direct negative effects on the heart as well as causing coronary vasospasm, dysrhythmia and seizures. Any elective procedures should be delayed if the patient appears acutely intoxicated. • Marijuana – produces mild to moderate sympathetic stimulation, increases heart rate and myocardial oxygen consumption, sometimes produces orthostatic hypotension. Severe tachycardia warrants cancellation of the case. • Amphetamines - Chronic abuse of amphetamines leads to tolerance and psychosis. Catecholamine stores may be depleted. Any elective procedure should be delayed if the patient appears acutely intoxicated. • Ecstasy – chemically resembles a combination of amphetamine and mescaline. Most common complications include hyperthermia, mental status changes, tachycardia, tachypnea, profuse sweating. No procedure should be performed till at least 6 hrs since last consumption.
Focused physical examination • At a minimum, focused physical examination should include the following: • Baseline vital signs (BP, HR, RR, room air SpO2) • Mental status, level of awareness • Body habitus • Auscultation of heart & lungs • Airway assessment • Any pre-existing neurologic or motor deficits • If the collected information suggests presence of a new serious medical problem, further detailed evaluation will be necessary and elective procedure should be delayed.
Perioperative Mortality The ASA classification system was not intended to be used in patients undergoing minor procedures under sedation/analgesia. Still, it remains useful in identifying high risk patients.
Guidelines to identify "high risk" patients • Difficult airway • Age >70 years • Sleep apnea or airway obstruction • Morbid obesity • Severe major organ system disease resulting in ASA score greater than 3 • Drug or alcohol abuse Although the majority of “high risk” patients are safely managed by an experienced practitioner, consideration should be given to consult an anesthesiologist if significant difficulties are expected or invasive monitoring is required.
Laboratory testing • Pre-procedure laboratory testing should be guided by the patient’s underlying medical condition and the likelihood that the results may affect the management. • A “routine” comprehensive laboratory testing for asymptomatic patients is discouraged since it increases cost but does not improve safety.
Specialist Consults • Whenever possible, appropriate medical specialists should be consulted before the administration of sedation to patients with significant underlying conditions. • Consideration should be given to consult an anesthesiologist if: • the patient is severely compromised or medically unstable • the patient has difficult airways • the patient has a know history of complicated or unsuccessful moderate sedation/analgesia
NPO Status • NPO Guidelines for healthy patients: • Clear liquids administered up to 2 hours before a scheduled procedure do not alter residual gastric volume when compared with the standard NPO overnight fasting • Solid food consumption warrants 6-8 hr delay of a procedure • The following factors slow down gastric emptying and increase the risk of pulmonary aspiration (strict 6-8 hrs NPO status is required for patients with these conditions - no solid or liquid food is allowed): • pregnancy - recent opioid administration • diabetes with neuropathy - severe pain • esophageal dysmotility - trauma • extreme anxiety or fear - known GERD • Obesity - hiatal hernia
Documentation of the Preoperative Evaluation • A standardized pre-sedation evaluation form should be completed prior to all sedation procedures. • The pre-sedation evaluation must be signed by the attending physician in all cases.
Pre-procedure Patient Education • By the end of the pre-sedation assessment the patient should be given detailed instructions pertinent to the planned procedure. At least the following issues should be addressed: • NPO • Time of arrival • Estimated procedure time • Medication instructions • Procedure-specific guidelines (e.g.: bowel preparation, dye preparations, etc) • Patients must be instructed to arrange for a competent adult to accompany them home. It is not acceptable to discharge a sedated patient from the hospital without an accompanying responsible adult. This designated person will assume post-sedation care and will follow the post-procedure instructions. If such person is not available, the procedure should be re-scheduled or the patient needs to be lodged or admitted overnight.
Last Preparations for the Procedure • The site, procedure and patient are accurately identified and documented according to the JCHAO requirements. Informed consent is re-checked. • Presence of a responsible adult for post-procedure home transportation or arrangements for lodging or overnight admission are confirmed. • The patient’s health status is re-evaluated immediately before the sedation procedure, and any changes from the last visit are documented and addressed. • Pre-procedure vital signs are checked and documented.
Part 3: Sedation Pharmacology
Titration to Clinical Effect • Titration to clinical effect is considered to be the safest approach to administering sedation/analgesia • Titration provides for slow, controlled rise in plasma level • Titration allows to combine different groups of medications safely
General Recommendations • The drugs should be titrated using minimal nesessary doses with sufficient interval in between to allow enough time for the drug to demonstrate its full effect. • Dosage requirements for sedation generally decrease in elderly patients, in debilitated patients and in patients with a significant cardiac, pulmonary or CNS disease. • Total doses and/or frequency of administration may also need to be reduced in patients with renal and/or hepatic dysfunction. • Drugs that are anesthetic agents (e.g. propofol, thiopental, methohexital, ketamine, etomidate, etc.) must be administered by an anesthesiologist, nurse anesthetist or by a licensed independent practitioner with sufficient training and ability to rescue a patient from general anesthesia.
Benzodiazepines (BDZ) The following effects on major systems are typically observed with the administration of BDZs: • Cardiovascular System: Systemic blood pressure is slightly decreased. • Respiratory System: This effect is usually insignificant unless the drugs are administered quickly or combined with other CNS depressants. • Central Nervous System: These drugs provide anti-seizures effect, produce anterograde amnesia, anxiolysis and centrally-mediated muscle relaxation.
Opioids • The following effects on major systems are typically observed with the administration of opioids: • Cardiovascular System: Bradycardia (fentanyl, morphine) or tachycardia (meperedine). Hypovolemic patients may develop hypotension. • Respiratory System: Respiratory depression or apnea. Extreme caution must be exercised when administering to patients with COPD or decreased respiratory reserve especially when combined with BDZ. • Central Nervous System : Euphoria, sedation. Addition of other CNS depressant drugs produces a synergistic effect. • A sudden increase in muscle tone ("stiff-chest" syndrome) causing difficulties with ventilation may occur if fentanyl is administered rapidly. The treatment consists of assisted ventilation and naloxone (IV). If hypertonus does not resolve within a minute, immediate consultation with an anesthesiologist should be requested.
Reversal Agents: General Consideration • Reversal agents should be available whenever opioids/BDZ are administered. • Before or concomitantly with pharmacological reversal, patients who become hypoxic or apneic should: • Continue to receive supplemental oxygen (should always (!) be available and administered to the sedated patient) • Be stimulated and encouraged to breath deeply • Receive mask ventilation if spontaneous ventilation becomes inadequate • After pharmacological reversal, patients should be observed long enough to ensure that cardio-pulmonary depression does not recur once the effect of the antagonist dissipates. • Routine administration of the reversal agents at the end of the case is not recommended.
Part 4: Monitoring and Documentation
Monitoring: The Basics • The administration of moderate sedation/analgesia for each patient is documented in the medical records regardless of the duration of the case. • At a minimum, the procedure flow sheet should include vital signs: 1. Before giving the first dose of the drug 2. After the administration of the sedatives/analgesics 3. At regular intervals during the procedure (max interval is 5 min) 4. During the initial recovery 5. Just before discharge • A designated individual ("monitoring person"), other than practitioner performing the procedure, must be present to provide monitoring: • Throughout the procedure a monitoring person should have no other responsibilities apart from the continuous monitoring of the patient. • Under certain circumstances institutional sedation policy may allow the monitoring person to assist with minor tasks while maintaining adequate monitoring once the patient's level of sedation / vital signs have stabilized.
Monitors • Minimal monitoring for moderate sedation procedures include: • Non-invasive blood pressure • Pulse oximetry • Respiration rate • Level of consciousness • Level of pain • ECG for patients with significant cardiac disease
Level of Consciousness • Evaluate the patient's behavior and response to stimuli on any available standardized sedation scale: • Observer's Assessment of Alertness / Sedation (OAA/S) • Sedation Visual Analogue Scale • Modified Ramsey Sedation Scale (RSS), e.g.:
Monitor Alarms • All monitors have alarms activated when the patient's vital signs deviate from the preset thresholds. These alarms become activated by default whenever the monitors are turned on. • The alarms must not be disabled during the procedure, and the volume of the alarm should be set high enough to be heard despite ambient noises of the procedure room. • Alarm limits should not be set broadly since it may obscure a dangerous situation. Initial alarm limits should be set approximately 20% above/below the patient's pre-sedation baseline vital signs.
Moderate Sedation Flow Sheet • During any sedation/analgesia procedures vital signs, given medications, performed measures and other intra-procedure events must be documented. Most facilities will use a flow sheet for this documentation. • Vital signs are recorded every 5 min, and any monitored artifacts should be documented to avoid confusion and misinterpretations during a later review of the record. • The flow sheet should be signed by the attending physician.
Part 5: Airway Management
Applicable Anatomy and Physiology of Airway • The upper airway obstruction (problems with structures above the vocal cords) is the most common cause of ventilation difficulties in sedated patients, and is usually due to the reduction of the space between the posterior pharyngeal wall and the base of the tongue. • The pharynx, epiglottis, and vocal cords play a role in protecting the lower airway from aspiration. The most important function is the glottic closure reflex in response to direct glottic or supraglottic stimulation, or as a reflex response to visceral stimulation. The physiologic exaggeration of this reflex, laryngospasm can compromise ventilation during a procedure.
Evaluation in the Airway • The primary goal of airway examination is to predict possible difficulties with spontaneous ventilation of sedated patients as well as with positive pressure ventilation / intubation, if it becomes necessary. • Every airway examination should include: • Oral cavity evaluation • Temporo-mandibular joint evaluation • Thyromental distance evaluation • Atlanto-occipital movement evaluation • Evaluation of the relationship between the tongue and other structures of the oral cavity (Mallampati classification)