Abstract
Keywords
1. Background
American Society of Anesthesiologists. Continuum of depth of sedation: definition of general anesthesia and levels of sedation/analgesia. 2014. https://www.asahq.org/standards-and-guidelines/continuum-of-depth-of-sedation-definition-of-general-anesthesia-and-levels-of-sedationanalgesia. (accessed April 5, 2021).
American Society of Anesthesiologists. Continuum of depth of sedation: definition of general anesthesia and levels of sedation/analgesia. 2014. https://www.asahq.org/standards-and-guidelines/continuum-of-depth-of-sedation-definition-of-general-anesthesia-and-levels-of-sedationanalgesia. (accessed April 5, 2021).
Levels of sedation | DEFINITION drug induced state where: |
---|---|
Minimal sedation(anxiolysis) | Patients respond normally to verbal commands. Cognitive function and coordination may be impaired, but ventilator and cardiovascular (CV) functions are unaffected. |
Moderate sedation/analgesia (conscious sedation) | Patients respond purposefully to verbal commands, either alone or accompanied by light tactile stimulation. No interventions are required to maintain a patient airway, and spontaneous ventilation is adequate. CV function is usually maintained. |
Deep sedation/analgesia | Patients cannot be easily aroused, but respond purposefully following repeated or painful stimulation. The ability to independently maintain ventilatory function may be impaired. Patients may require assistance in maintaining a patent airway, and spontaneous ventilation may be inadequate. CV function is usually maintained. |
General anesthesia | Patients are not arousable, even by painful stimulation. The ability to independently maintain ventilatory function is often impaired. Patients often require assistance in maintaining a patent airway, and positive pressure ventilation may be required because of depressed spontaneous ventilation or drug-induced depression of neuromuscular function. CV function may be impaired. |
2. Clinical questions
2.1 What medication regimens are used for moderate sedation, deep sedation, or general anesthesia?
American Society of Anesthesiologists. Continuum of depth of sedation: definition of general anesthesia and levels of sedation/analgesia. 2014. https://www.asahq.org/standards-and-guidelines/continuum-of-depth-of-sedation-definition-of-general-anesthesia-and-levels-of-sedationanalgesia. (accessed April 5, 2021).
American Society of Anesthesiologists. Continuum of depth of sedation: definition of general anesthesia and levels of sedation/analgesia. 2014. https://www.asahq.org/standards-and-guidelines/continuum-of-depth-of-sedation-definition-of-general-anesthesia-and-levels-of-sedationanalgesia. (accessed April 5, 2021).
Drugs | Usual initial dose | Maximum initial dose | Usual incremental dose | Maximum incremental dose |
---|---|---|---|---|
Fentanyl (opioid analgesic) | 50−100 mcg | 200 mcg | 50−100 mcg | 100 mcg |
Midazolam (benzodiazepine sedative) | 1−3 mg | 4 mg | 1−2 mg | 2 mg |
Drugs | Maximum recommended single dose | Onset of action | Duration | Comments |
---|---|---|---|---|
Fentanyl (opioid analgesic) | 1−2 mcg/kg IV | Almost immediate | 0.5−1 h | May be repeated once |
Nalbuphine (opioid analgesic) | 10−20 mg IV/IM | 2−3 min IV<15 min IM | 3−6 h |
|
Meperidine (opioid analgesic) | 50−100 mg IM/SQ | 10−15 min | 2−4 h |
|
Midazolam (benzodiazepine sedative) | 2.5 mg | 3−5 min | < 2h | Initial dose 1−2.5 mgAdminister slowly with 2−3 min between doses to assess effect of previously administered dose.May repeat in 1 mg doses not to exceed a total of 5 mg to maintain desired depth of sedation |
2.2 How effective are moderate sedation, deep sedation, and general anesthesia for pain control during abortion procedures?
National Institute for Health and Care Excellence. Abortion care: Anaesthesia or sedation for surgical abortion; London, UK: 2019. https://www.nice.org.uk/guidance/ng140/evidence/n-anaesthesia-or-sedation-for-surgical-abortion-pdf-248581907032. (accessed June 29, 2021).
National Institute for Health and Care Excellence. Abortion care: Anaesthesia or sedation for surgical abortion; London, UK: 2019. https://www.nice.org.uk/guidance/ng140/evidence/n-anaesthesia-or-sedation-for-surgical-abortion-pdf-248581907032. (accessed June 29, 2021).
2.3 What preprocedure patient evaluation or patient preparation is necessary for moderate sedation, deep sedation, or general anesthesia?
American Association of Nurse Anesthetists. Analgesia and anesthesia for the substance use disorder patient - practice considerations. Park Ridge, IL2019. https://www.aana.com/docs/default-source/practice-aana-com-web-documents-(all)/professional-practice-manual/analgesia-and-anesthesia-for-the-substance-use-disorder-patient.pdf?sfvrsn=3e6b7548_2#:∼:text=Effective%20analgesia%20and%20anesthesia%20care,managing%20withdrawal%2C%20and%20preventing%20relapse. (accessed April 5, 2021).
2.4 Which patients are typically not appropriate for management in out-of-hospital ambulatory care facilities with moderate sedation, deep sedation, or general anesthesia? Which patient factors influence patient safety during anesthesia?
American Society of Anesthesiologists. ASA physical status classification system. 2014. https://www.asahq.org/standards-and-guidelines/asa-physical-status-classification-system. (accessed June 24, 2021).
American Society of Anesthesiologists. ASA physical status classification system. 2014. https://www.asahq.org/standards-and-guidelines/asa-physical-status-classification-system. (accessed June 24, 2021).
ASA physical status classification | Definition | Examples, including, but not limited to: |
---|---|---|
ASA I | A normal healthy patient | Healthy, nonsmoking, no or minimal alcohol use |
ASA II | A patient with mild systemic Disease | Mild diseases only without substantive functional limitations. Examples include (but are not limited to): current smoker, social alcohol drinker, pregnancy, obesity (30<BMI<40), well- controlled diabetes (DM)/hypertension (HTN), mild lung disease |
ASA III | A patient with severe systemic disease | Substantive functional limitations; 1 or more moderate to severe diseases. Examples include (but are not limited to): poorly controlled DM or HTN, chronic obstructive pulmonary disease (COPD), morbid obesity (BMI ≥40), active hepatitis, alcohol dependence or abuse, implanted pacemaker, moderate reduction of ejection fraction, end-stage renal disease (ESRD) undergoing regularly scheduled dialysis, premature infant postconceptual age < 60 weeks, history (>3 months) of myocardial infarction (MI), cerebrovascular accident (CVA), transient ischemic attack (TIA), or coronary artery disease (CAD)/stents. |
ASA IV | A patient with severe systemic disease that is a constant threat to life | Examples include (but are not limited to): recent (<3 months) MI, CVA, TIA, or CAD/stents, ongoing cardiac ischemia or severe valve dysfunction, severe reduction of ejection fraction, sepsis, disseminated intravascular coagulation, acute respiratory distress or ESRD not undergoing regularly scheduled dialysis. |
ASA V | A moribund patient who is not expected to survive without the operation | Examples include (but are not limited to): ruptured abdominal/thoracic aneurysm, massive trauma, intracranial bleed with mass effect, ischemic bowel in the face of significant cardiac pathology or multiple organ/system dysfunction. |
ASA VI | A declared brain-dead patient whose organs are being removed for donor purposes |
2.5 What qualifications must providers have to safely administer moderate sedation, deep sedation, and general anesthesia? What policies and standards are available?
American Society of Anesthesiologists. Statement on granting privileges for administration of moderate sedation to practitioners who are not anesthesia professionals. 2016. https://www.asahq.org/standards-and-guidelines/statement-of-granting-privileges-for-administration-of-moderate-sedation-to-practitioners. (accessed June 24, 2021).
Anesthesia professional – includes anesthesiologist, certified registered nurse anesthetist (CRNA) or anesthesiologist assistant (AA). |
Nonanesthesiologist sedation practitioners - licensed physicians who have not completed postgraduate training in anesthesiology but are specifically trained to administer moderate sedation. |
Supervised sedation professionals – includes licensed registered nurses, advanced practice nurses, and physician assistants. |
American Association of Nurse Anesthetists. Standards for nurse anesthesia practice. Park Ridge, IL 2019. https://www.aana.com/docs/default-source/practice-aana-com-web-documents-(all)/professional-practice-manual/standards-for-nurse-anesthesia-practice.pdf?sfvrsn=e00049b1_18. (accessed June 24, 2021).
American Association of Nurse Anesthetists. Scope of nurse anesthesia practice. Park Ridge, IL 2020. https://www.aana.com/docs/default-source/practice-aana-com-web-documents-(all)/professional-practice-manual/scope-of-nurse-anesthesia-practice.pdf?sfvrsn=250049b1_6. (accessed June 24, 2021).
American Association of Nurse Anesthetists. Scope of nurse anesthesia practice. Park Ridge, IL 2020. https://www.aana.com/docs/default-source/practice-aana-com-web-documents-(all)/professional-practice-manual/scope-of-nurse-anesthesia-practice.pdf?sfvrsn=250049b1_6. (accessed June 24, 2021).
American Society of Anesthesiologists. Advisory on granting privileges for deep sedation to non-anesthesiologist physicians. 2017. https://www.asahq.org/standards-and-guidelines/advisory-on-granting-privileges-for-deep-sedation-to-non-anesthesiologist-physicians. (Accessed June 24, 2021).
American Society of Anesthesiologists. Statement on granting privileges to non-anesthesiologist physicians for personally administering or supervising deep sedation. 2017. https://www.asahq.org/standards-and-guidelines/statement-on-granting-privileges-to-nonanesthesiologist-physicians-for-personally-administering-or-supervising-deep-sedation#:∼:text=Non%2Danesthesiologist%20physicians%20may%20neither,and%20rescue%20from%20general%20anesthesia. (Accessed June 24, 2021).
American Society of Anesthesiologists. Advisory on granting privileges for deep sedation to non-anesthesiologist physicians. 2017. https://www.asahq.org/standards-and-guidelines/advisory-on-granting-privileges-for-deep-sedation-to-non-anesthesiologist-physicians. (Accessed June 24, 2021).
2.6 What monitoring is required for moderate sedation, deep sedation, or general anesthesia?
2.7 What are the anesthesia-related side effects and risks associated with moderate/deep sedation and general anesthesia? What equipment is necessary to manage these risks?
National Institute for Health and Care Excellence. Abortion care: Anaesthesia or sedation for surgical abortion; London, UK: 2019. https://www.nice.org.uk/guidance/ng140/evidence/n-anaesthesia-or-sedation-for-surgical-abortion-pdf-248581907032. (accessed June 29, 2021).
Intravenous equipment | Gloves |
Tourniquets | |
Alcohol wipes | |
Sterile gauze pads | |
Intravenous catheters | |
Intravenous tubing | |
Intravenous fluid | |
Assorted needles for drug aspiration, intramuscular injection | |
Appropriately sized syringes | |
Tape | |
Basic airway management equipment | Source of compressed oxygen (tank with regulator or pipeline supply with flowmeter) |
Source of suction | |
Suction catheters | |
Yankauer-type suction | |
Face masks | |
Self-inflating breathing bag-valve set | |
Oral and nasal airways | |
Lubricant | |
Advanced airway management equipment (for practitioners with intubation skills) | Laryngeal mask airways |
Laryngoscope handles | |
Laryngoscope blades | |
Endotracheal tubes (cuffed 6.0, 7.0, 8.0 mm ID) | |
Stylet (appropriately sized for endotracheal tubes) | |
Pharmacologic antagonists | Naloxone |
Flumazenil | |
Emergency medications | Epinephrine |
Ephedrine | |
Vasopressin | |
Atropine | |
Nitroglycerin (tablets or spray) | |
Amiodarone | |
Lidocaine | |
Glucose, 50% | |
Diphenhydramine | |
Hydrocortisone, methylprednisolone or dexamethasone | |
Diazepam or midazolam |
2.8 What postsedation care is needed for moderate sedation, deep sedation, or general anesthesia?
2.9 Does deep sedation or general anesthesia during abortion procedures require routine endotracheal intubation?
2.10 Is fasting necessary before moderate or deep sedation for abortion in ambulatory care settings?
National Institute for Health and Care Excellence. Abortion care: Anaesthesia or sedation for surgical abortion; London, UK: 2019. https://www.nice.org.uk/guidance/ng140/evidence/n-anaesthesia-or-sedation-for-surgical-abortion-pdf-248581907032. (accessed June 29, 2021).
3. Clinical recommendations
- •A combination of intravenous fentanyl and midazolam is effective in reducing pain associated with first-trimester surgical abortion (GRADE 1B).
- •Patients receiving sedation and analgesia should be monitored by pulse oximetry both during and after surgery to detect oxygen desaturation and hypoxemia (GRADE 1C).
- •The ventilatory function of patients receiving sedation and analgesia should be continually monitored by observation or auscultation (GRADE 1C).
- •The ASA classification system can be used as a guide to assess a patient's procedure-related risk (GRADE 2C).
- •Supplemental oxygen should be used to decrease the frequency of hypoxia. Its use should be considered when administering moderate sedation and recommended when administering deep sedation unless specifically contraindicated for a particular patient (GRADE 1C).
- •Low-risk patients undergoing surgical abortion in the first and second trimester may safely receive moderate or deep sedation without routine endotracheal intubation (GRADE 1C).
- •General anesthesia for dilation and evacuation is commonly administered with a propofol infusion and an opioid (GRADE 1C).
- •Preoperative assessment should include a review of the preoperative medical history; review of systems; physical examination with measurement of vital signs, airway assessment, and cardiovascular exam; patient's analgesic and sedation goals corresponding to the anticipated procedure-related pain (GRADE 1C).
- •Several factors may influence the decision of whether a patient is an appropriate candidate for out-of-hospital anesthesia, including provider preference (whether the surgeon or anesthesia provider), distance from nearest hospital that can accommodate postabortion complications, and most importantly, the patient's surgical risk based on her comorbidities and the facility's ability to manage potential complications secondary to these comorbidities (GRADE 1C).
- •Among individuals whose deep sedation progresses to unintended general anesthesia, such care should be provided, medically directed, or supervised by an anesthesiologist, the operating practitioner, or another licensed physician with specific training in sedation, anesthesia, and rescue techniques related to general anesthesia (GRADE 1C). Otherwise, routine general anesthesia should only be administered by anesthesia professionals (i.e., anesthesiologists, nurse anesthetists, and certified anesthesiologist assistants) (GRADE 1C).
- •Postsedation care requires patient monitoring until the patient resumes near baseline level of consciousness (GRADE 1C).
4. Recommendations for future research
- •Comparative efficacy of medication regimens in first- and second-trimester surgical abortion, especially in light of drug shortages.
- •Comparative safety of medication regimens with regard to inducing deeper sedation than intended and adverse events such as pulmonary aspiration, unanticipated intubation, and hospital transfer.
- •Bleeding parameters associated with administration of newer halogenated agents used for general anesthesia.
- •Efficacy and safety of analgesic options for obese individuals and patients with other significant medical comorbidities.
5. Sources
6. Intended audience
Author Contributions
Declaration of Competing Interest
Funding
Appendix A. Key for Recommendations Summary
Symbol | Meaning |
1 | Strong recommendation |
2 | Weaker recommendation |
A | High quality evidence |
B | Moderate quality evidence |
C | Low quality evidence, clinical experience, or expert consensus |
Appendix. Supplementary materials
References
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