Monitored Anesthesia Care Flashcards
What is monitored anesthesia care?
A specific anesthesia service for diagnostic or therapeutic procedures performed under local anesthesia along with sedation and analgesia, titrated to a level that preserves spontaneous breathing and airway reflexes.
What is the components of MAC?
Actually, an anesthesia service in which our expertise is requested by a surgeon or proceduralist to safely provide the sedation needs for a given patient for a given procedure
What is an example of MAC?
CRNA providing sedation/analgesia for a patient undergoing a breast mass incision in which the surgeon used a local anesthetic to infiltrate the surgical area
What percentage of anesthesa services nationwide does MAC account for?
MAC alone or with local anesthesia accounts for a relatively high percentage of anesthesia services nationwide (10-30%).
What are the goals of MAC?
Sedation, Anxiolysis, Analgesia
How is recovery with MAC different then GA?
Less physiologic disturbance and a more rapid recovery
MAC: Depression of the central nervous system occurs in a ________ manner
dose dependent
What is the key difference between MAC and moderate sedation/analgesia?
Monitored anesthesia care is an [physician] anesthesia provider service provided to an individual patient. Whereas “Moderate Sedation/Analgesia” is a service directed by the Proceduralist who is preoccupied in focusing on successfully completing the scheduled procedure.
What is the effect of a proceduralist delivering moderate sedation and analgesia?
The Proceduralist may not be cognizant of ongoing pathophysiologic effects of sedatives given or procedure/position changes
Monitored anesthesia care should be subject to the same level of ________ as general or regional anesthesia
payment
What is the requirements of a MAC provider?
must be qualified and skilled to rescue an airway or convert to general anesthesia if the situation demands.
What are key requirements of the anesthesia provider during MAC procedures? (3)
- Support of vital functions
- Management of possible intraoperative problems
- Provision of psychological support
What specific monitoring occurs with MAC anesthesia? (6)
Vigilant monitoring comprises of continuous communication with the patient (verbal anesthesia), observation of parameters such as oxygenation, ventilation, circulation, temperature, as well as vigilance for local anesthesia toxicity.
Why is capnography important in MAC cases?
is an essential monitoring component of MAC to detect apnea at an earliest opportunity.
What is important to know about sedation?
a continuum, which ranges from minimal, to moderate , to deep sedation to GA.
What is another term for minimal sedation?
anxiolysis
The terms MAC and sedation are sometimes used ________
interchangeably- but not the same
What is the sedation for MAC?
The sedation provided for a MAC anesthetic occurs on a continuum (blurred) and the line between Deep sedation and GA is not always black and white
When moderate sedation is needed- we are usually ________
consulted
We are _________by The Joint Commission if deep to GA
Required
Who can administer minimal sedation?
Versus minimal sedation by an RN or “local” only by surgeon- monitored by a nurse
MAC cases can sometimes be the most ________
challenging
Why is MAC consider a challenging situation?
Balancing the expectations/wants of the surgeon (even the patient) to what a MAC anesthetic provides
Define moderate sedation.
A drug-induced depression of consciousness during which patients respond to purposefully to verbal commands, either alone or accompanied by light tactile stimulation
What is the reflex response of moderate sedation?
Reflex withdrawal from a painful stimulus is not considered a purposeful response
What are the interventions for moderate sedation?
No interventions are required to maintain a patent airway, and spontaneous ventilation is adequate.
What is the cardiovascular function by moderate sedation?
Cardiovascular function is usually maintained.
Define deep sedation/analgesia.
A drug-induced depression of consciousness during which patients cannot be easily aroused but respond purposefully following repeated or painful stimulation
What is the respiratory effects of deep sedation/analgesia?
- The ability to independently maintain ventilatory function MAY be Impaired.
- Patients MAY require assistance and maintaining a patent airway and spontaneous ventilation may be inadequate
What is the cardiovascular function by deep sedation/analgesia?
Cardiovascular function is usually maintained- obviously need our airway and pharmacologic expertise…
Define anesthesia.
Consists of general anesthesia and spinal or major regional anesthesia, does not include local anesthesia.
Define general anesthesia.
is a drug-induced loss of consciousness during which patients are not arousable even by painful stimulation.
What is the respiratory effects of general anesthesia?
- 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 neuro-muscular function
What is the cardiovascular function by general anesthesia?
Cardiovascular function may be impaired.
Who can preform deep sedation, regional blocks and general anesthesia?
While each level shares some common accreditation requirements, must be performed by an anesthesia provider or LIP with medical staff privileges to administer deep sedation, regional or general anesthesia in accordance with hospital policy and state scope of practice laws.
Who can assess deep sedation, regional blocks and general anesthesia?
This assessment may not be delegated to a non-privileged individual.
Who can preform moderate sedation?
The organization determines who is qualified toperform the assessment consistent with competencies of staff, scope of practice, rules and regulation and State.
Continuum of care.
Slide 8
What is the impact of Monitor Anesthesia Care on the continuum of depth of sedation?
Monitored Anesthesia Care (“MAC”) does not describe the continuum of depth of sedation, rather it describes “a specific anesthesia service performed by a qualified anesthesia provider, for a diagnostic or therapeutic procedure.
What are the indications for MAC?
the need for deeper levels of analgesia and sedation than can be provided by moderate sedation (including potential conversion to a general or regional anesthetic
What are the characteristics of minimal sedation (anxiolysis)?
- normal response to verbal stimulation
- airway unaffected
- spontaneous ventilation unaffected
- cardiovascular function unaffected
What are the characteristics of moderate sedation and/or analgesia (conscious sedation)?
- purpose response to verbal or tactile stimulation
- no airway intervention required
- adequate spontaneous ventilation
- adequate cardiovascular function
What are the characteristics of deep sedation and/or analgesia?
- purposeful response following repeated or painful stimulation
- airway intervention may be required
- spontaneous ventilation may be inadequate
- cardiovascular function usually maintained
What are the characteristics of general anesthesia?
- unarousable even with painful stimulus
- airway intervention often required
- spontaneous ventilation frequently inadequate
- cardiovascular function may be impaired
What is the difference between sedation and MAC?
MAC is an anesthetic service that is requested by surgeons/proceduralists to monitor a patient (level of sedation may be light to deep)
What is a similarity of sedation and MAC?
Similar medications may be used
What are the qualifications of providers when administering medications?
- Prepared and qualified to convert to GA when necessary
- Capable and able to intervene to rescue the patient’s airway, etc.
What is true about the level of sedation in sedation cases?
In sedation cases: the level of sedation should not be so deep that the patient cannot protect and maintain their own airway
What is the principle component of MAC?
It’s not about what drugs or how much, but about what drugs and how much for this patient and how they are used
What is true about the sedation required for some pts?
Some patients may only require “minimal” sedation, but the small amount needed may precipitate an adverse event or the transient period of sedation needed (for local injection) may require a deeper plane that borders general anesthesia
What is the focus of MAC?
- MAC the focus is monitoring and protecting the airway, hemodynamic and physiologic issues.
- Must be prepared to convert to general anesthesia (equipment readily available).
What is true about moderate sedation?
not expected to induce depths of sedation that would impair the patient’s respiratory function or ability to maintain the integrity of one’s airway
What is the difference between of MAC and GA (Sedation to maintain an MAC)? (3)
- Complete loss of consciousness
- Lack of arousability to noxious stimuli
- Respiratory and cardiovascular depression
MAC: Significant ___________ depression
central nervous system
What is the line present in MAC?
Fine line with loss of consciousness and not being easily aroused
What is the response of MAC to stimuli?
- Responds purposefully to noxious stimuli
- Use of local anesthetics
What might occur with MAC?
Respiratory depression may occur
What needs to be monitored during MAC?
Monitor hypercapnia (not always easy to monitor capnography accurately with nasal cannula or face shield)
What may be required during MAC?
-May require airway intervention
E.g. Chin lift, jaw thrust, OPA, NPA, etc.
What cardiovascular effect may occur with MAC?
Cardiovascular depression
What are the primary approaches of MAC (4)?
- Continuous infusion with prn boluses
- Manual boluses
- Target controlled infusions
- Patient controlled sedation
What is patient controlled sedation?
Programed bolus and lock out period
What is the characteristics of ideal sedatives of monitor anesthesia care? (4)
- Rapid onset and recovery
- Easy titration
- High clearance
- Minimal side effects
What are effects commonly of monitor anesthesia care (2)?
Respiratory and Cardiovascular depression
What are some medications typically? (9)
Propofol, Ketamine, Ketofol, Propofol & Remifentanil, Propofol & fentanyl, dexmedetomidine, versed, versed and fentanyl, versed and fentanyl and propofol
What are the sedation techniques of MAC?
Due to dearth of an ideal agent, sedation techniques for MAC often utilize a combination of agents to provide analgesia, amnesia, and hypnosis with complete and rapid recovery that suits a particular operative procedure with minimum side effects
What are some minimal side effects that MAC has helps to combat?
like postoperative nausea and vomiting (PONV), prolonged sedation, and cardiorespiratory depression
What needs to be factor into in choosing drugs for MAC?
Apart from the distribution and elimination half-life, factors like context sensitive half-time, effect-site equilibration, and potential of interaction with other drugs need to be taken into account while choosing the drugs
What providers faster onset and better predictability of drug effect?
Targeting the effect-site concentration rather than blood concentration provides faster onset and better predictability of drug effect
How can drug titratability be achieved?
can be achieved with the use of a wide variety of drug delivery techniques including intermittent boluses, target-controlled infusion, variable-rate infusion, and patient-controlled sedation (PCS
What is more effective the PMS and PCS?
The patient-maintained sedation (PMS) is found to be more effective than PCS in terms of patient satisfaction and minimizing side effect
What is essential for success of MAC?
Patient cooperation is essential for success – choose your patients (and medications) wisely
Why is MAC often considered safer?
MAC often thought to be “safer” than general anesthesia because of potentially decreased dosages of medication
What is true about the airway during a MAC case?
Airway is not secured during MAC which adds a layer of complexity and danger (positioning- patient may be prone or 180 away)
What is important to realized about NORA (non-operating room cases) cases? (3)
lack of familiarly, equipment, support
What are some side effects of MAC (4)?
Airway obstruction, desaturation, aspiration
Cardiac collapse
What may be required during MAC?
Conversion to GA when necessary
What are some key monitors associated with MAC?
temperature and end tidal carbon dioxide
What needs to be a precaution when using MAC cases above the xiphoid?
The use of oxygen delivery- being cognizant of MAC cases above the xiphoid and risks of airway fire
What are the characteristics of to guide the selection of the appropriate sedation technique?
Operation time, clinical condition, age of the patient, and the need to convert to general or regional anesthesia
What is required in geriatric population? Why?
Fewer sedative drugs are required in geriatric population, as chances of desaturation and cardiovascular instability are more.
What is the ideal cases for MAC?
-Short case where the patient needs to be “street ready”, case with varying sedation needs throughout, Patient have underlying issues and Or a long case where the most intense part of the case is the initial local anesthetic injection/infiltration
What is a street ready case that MAC can be used for? (2)
colonoscopy, EGD
What is an example of a case with varying sedation needs?
e.g., pain case where surgeon injects local anesthetic and but needs patient responsive afterwards to identify nerve root to ablate then deepen for ablation or “awake” carotid endarterectomy where surgeon needs a ”still,” comfortable patient but cooperative
What is an example of patient have underlying issues?
torn rotator cuff or back issues that makes them uncomfortable lying flat on a hard surface for long periods of time- the majority of the discomfort is not the surgery itself
What is important to remember with MAC?
prone, patient turned away from you
Remembering what may be moderate sedation for one patient can easily be ______________
deep for another
What is a manual airway maneuvers?
Chin Lift
What is the characteristics of the typical MAC nasal cannula?
- small pin holes deliver pillow of oxygen around both nose and mouth
- Uni-junction of sampling ports prevents dilution from non breathing source
- Increased surface area providers greater sampling accuracy in the presence of low tidal volumes
Having _______ and _______ equipment readily available
airway and resuscitation equipment
What is an important equipment of the MAC?
Vigilance to monitor airway and any changes.
What is an airway alternative that can help in emergency?
Airway adjunct/assist as needed with bag/mask (NOT your goal but a rescue!)
What can effect the readings of EtcCO2?
problematic for “perfect” tracings with N/C and face shields
What does a moving chest not indicate?
not always indicate air exchange for the patient.
What is sufficient for shorter cased?
Intermittent boluses (usually suffices for shorter cases)- “titrate to effect”
What is important for longer cases?
Infusions with loading bolus and intermittent boluses as needed (Consider for longer cases but many providers stick to a bolus regimen)
What is the most common infusion for MAC?
Propofol and dexmedetomidine the more common infusions but can bolus with either
What are some infusion pumps used?
Alaris-type pumps or syringe pumps
What assessment is greatly important for MAC cases?
Assessment of the depth of sedation is of great importance as it helps in titrating drug administration to prevent awareness or excessive anesthetic depth and thereby promotes patient safety and early recovery.
What can help to measure the depth of consciousness during MAC?
The bispectral index (BIS) is effective to measure the depth of consciousness during MAC.
What is increased risk with MAC?
The incidence of apnea during MAC is high, and the incidence increases as BIS decreases.
What is placed in many signs with MAC?
signs placed outside the OR to indicate an “awake” patient. The constant reminder to personnel in the room of the patient’s sedative state.
What is the common MAC regimen?
+/- (1-2 mg) Versed in preop, +/- (25-100 mcg) fentanyl with propofol infusion (25-100 mcg/kg/min)
What is the common MAC regimen for colonscopy?
propofol only
What is the benefits of combination medications?
maximize the benefits of one while decreasing the side effects
What effect does combo of medications have on MAC?
Adds to the complexity and must know the synergisms among the agents that you use (reduced doses when using in combinations)
What does it mean to “chase your tail”?
that 25-50 mcg rescue bolus of fentanyl may induce apnea in the presence of midazolam and propofol infusion: opioids are sedating too and may be used as sole agents!
Careful _______ of agents is needed with MAC.
titrations
What is the guidelines for propofol?
(25-100+ mcg/kg/min) loading bolus and incremental boluses as needed (key is not to induce GA!)
What is the guidelines for propofol with Ketamine?
Bolus 0.2-0.8 mg/kg followed by 5-120 mcg/kg/min (Nagelhout, p. 103)- this seems high as other sources note 2.5-15 mcg/kg/min (Morgan & Mikhail; Cusick, 2020)
What is the post op pediatric analgesia and sedation dose of ketamine?
1-2 mg/kg/hr for pediatric POSTOP analgesia/sedation (not routinely used for postop pain- need infusion and does NOT replace an opioid as a sole agent for postop pain)
What is a concern with ketamine?
concerns and need for midazolam, glycopyrrolate? Do not want the patient dissociative, “squirrely”
What is a side effect that limits ketamines use? When is it normally indicated?
The side effects of ketamine limit its use as a sole agent- usually used as an adjunct in combination with other agents or as a preemptive pain strategy). Usually giving boluses to blunt response to a block or local infiltration (e.g., 10 mg bolus increments for an adult for a total ~30 mg)
What is Ketofol?
combo to allow for the analgesic of ketamine at reduced doses to attenuate psychosomatic issues, salivation yet offset the respiratory/ hemodynamics issues of propofol)
What is the combo of Ketofol?
1:1 combination at 5-10 ml/hr (although Flood advises not to comix)
What is the dose of propofol and remifentanil?
- starting on the lower end of ranges when combining)
- Remi loading dose 0.5-1 mcg/kg with infusion 0.025-0.2 mcg/kg/min
What is the dose of propofol and alfentanil?
-Alfentanil loading dose 10-25 mcg/kg with infusion 0.25-1 mcg/kg/min
(Flood states higher dose for maintenance of anesthesia: note in mcg/kg/hr; Nagelhout in mcg/kg/min)
What is the dose of dexmedetomidine?
(0.2- 0.7 mcg/kg/hr) need to load or ½ load depends on start of infusion, patient and hemodynamics
What is the dose of etomidate?
0.1-0.2 mg/kg then 0.05 mg/kg q 3-5min
When is an indication for fentanyl only?
just fentanyl only- eye cases with topical local anesthesia for elderly
What is a common MAC drug strategy?
Versed, fentanyl, propofol
What is growing in awareness in health care worldwide?
health reforms and allocation of limited healthcare resources in all aspects of medical practice. MAC isno exception to that
What are the efforts that MAC strives for?
All efforts are made to maintain parity between quality, efficiency, and affordability.
What is an issue of concern with MAC?
The ever rising cost of MAC is also an issue of concern and we should weigh the accrued benefits against the increased cost involved.
