Unit 12: Miscellaneous Topics Flashcards
Define an ionic bond, covalent bond, and polar covalent bond
Ionic Bond: complete transfer of valence electrons from one atom to another
- leaves one atom w/ a negative charge and the other w/ a positive charge
- metals, acids, and bases tend to form ionic bonds
Covalent Bond: equal sharing of electrons (strongest type of bond)
- single bond is created when 1 pair is shared, double bond = 2 shared
Polar Covalent Bond: an “in-between” type of bond
- atoms share electrons but electrons tend to remain closer to one atom than the other
- one area of the molecule is relatively positive and the other is relatively negative
What are Van der Waals forces?
Very weak intermolecular force that hold molecules of the same type together
-weakest type of molecular attraction
What is Dalton’s Law? List several examples of how it can be used in the OR
Dalton’s Law of Partial Pressures = total pressure is equal to the sum of the partial pressures exerted by each gas in the mixture
P total = P1 + P2 + P3
Ways to apply it:
-calculate partial pressure of an unmeasured gas
-calculate total pressure
-convert partial pressure to volumes percent
-convert volumes percent to a partial pressure
At sea level, the agent monitor measures the end-tidal Sevo as 3%. What is the partial pressure of Sevo in the exhaled tidal volume?
Partial Pressure = Volumes % x Total Pressure
0.03 x 760 mmHg = 22.8 mmHg
*application of Dalton’s Law
What is Henry’s Law? List several examples of how it can be used in the OR
At a constant temperature, the amount of gas that dissolves in a solution is directly proportional to the partial pressure of that gas over the solution
-the higher the gas pressure, the more of it will dissolve into a liquid (assuming constant temp)
Increased Temp = Decreased Solubility
Decreased Temp = Increased Solubility
Application:
-anesthetic emergence is prolonged in the hypothermic pt
-dissolved O2 in the O2 carrying capacity equation
What is Fick’s Law of Diffusion?
Describes the transfer rate of gas through a tissue medium
Rate of Transfer is Directly Proportional To:
-partial pressure difference (driving force)
-diffusion coefficient (solubility)
-membrane surface are
Inversely Proportional To:
-membrane thickness
-molecular weight
What are the clinical examples of Fick’s Law of Diffusion?
-Diffusion hypoxia
-Pt w/ COPD has a reduced alveolar surface area and therefore has a slower rate of inhalation induction
-Calculation of CO
-Drug transfer across the placenta
What are Boyle’s, Charles’s, and Gay-Lussac’s Laws?
Boyle’s Law: P1 x V1 = P2 x V2 – inverse relationship
Charles’s Law: V1/T1 = V2/T2 – direct relationship
Gay-Lussac’s Law: P1/T1 = P2/T2 – direct relationship
What are the clinical examples of Boyle’s Law?
Pressure x Volume – (constant = temp)
-Diaphragm contraction increases tidal volume
-Pneumatic bellows
-Squeezing an Ambu bag
-Using the bourdon pressure gauge to calculate how much O2 is left in a cylinder (assumes a given flow rate)
What are the clinical examples of Charles’s Law?
Volume / Temperature – (constant = pressure)
-LMA cuff ruptures when placed in an autoclave
What are the clinical examples of Gay-Lussac’s Law?
Pressure / Temperature – (constant = volume)
-Oxygen tank explodes in heated environment
What is the function of the ideal gas law?
Ideal Gas Law unifies all 3 gas laws into a single equation: PV = nrT
P = pressure
V = volume
n = # of moles
r = constant 0.0821 L-atm/K/mole
T = temperature
What is Ohm’s Law?
Current passing through a conductor is directly proportional to the voltage and inversely proportional to the resistance
-can adapt to understand fluid flow
Current = Voltage Difference / Resistance
OR
Flow = Pressure Gradient / Resistance
How is Poiseuille’s Law related to Ohm’s Law?
Poiseuille’s law is a modification of Ohm’s law that incorporates vessel diameter, viscosity, and tube length
Q = πR^4ΔP / 8 nL
Q - blood flow
R - radius
ΔP - arteriovenous pressure gradient (Pa - Pv)
n - viscosity
L - length of tube
How do changes in radius affect laminar flow?
Altering radius of the tube exhibits the greatest impact on flow
R = 1^4: 1x1x1x1 = 1
R = 2^4: 2x2x2x2 = 16
R = 3^4: 3x3x3x3 = 81
R = 4^4: 4x4x4x4 = 256
How can we apply Poiseuille’s law to the administration of a unit of PRBCs?
PRBCs can be delivered faster if we:
-increase the radius w/ a large bore IV
-increase the pressure gradient w/ a pressure bag and/or increase height of IV pole
-decrease viscosity by diluting blood w/ 0.9% NS and/or running it through a fluid warmer
-decrease the length by not using longer tubing than you really need
What does Reynold’s number tell you?
Predicts the type of flow (laminar, turbulent, and transitional) that will occur in a given situation
Re < 2000: laminar flow is dependent on gas viscosity (Poiseuille’s Law)
Re > 4000: turbulent flow is dependent on gas density (Graham’s Law)
Re 2000-4000: transitional flow
Reynolds’ # = Density x Diameter x Velocity / Viscosity
**in status asthmaticus – airway resistance is increased, thus increases turbulent flow and WOB (treat w/ Heliox to improve Reynold’s # by reducing density)
What is Bernoulli’s principal?
Describes the relationship between the pressure and velocity of a moving fluid (or gas)
-if fluid’s velocity is high – pressure exerted on the walls of the tube will be low
-if fluid’s velocity is low – pressure exerted on the walls of the tube will be high
*ex: think of a river:
- wide river = water moves slowly
- narrow river = water moves faster –> slow water exerts more pressure on riverbank than fast narrow river
What is the Venturi effect? Give examples
Application of the Bernoulli principle
- as airflow in a tube moves past the point of constriction, the pressure at the constriction decreases (Bernoulli principle) and if the pressure inside the tube falls below atmospheric pressure, then air is entrained into the tube (Venturi effect)
- adjusting diameter of the constriction allows for control of the pressure drop and the amount of air that is sucked into the tube
Ex: jet ventilator, Venturi, and nebulizer
What is the Coanda effect? Give examples
Describes how a jet flow attaches itself to a nearby surface and continues to flow along that surface even when the surface curves away from the initial jet direction
Ex: wall-hugging jet of mitral regurgitation and water that follows the curve of a glass
How do you calculate the law of Laplace for a sphere? How about for a cylinder?
Sphere: Tension = (Pressure x Radius) / 2
-examples: alveolus, cardiac ventricle, saccular aneurysm
Cylinder: Tension = Pressure x Radius
-examples: blood vessels, aortic aneurysm
*Law of Laplace illustrates the relationship between the wall tension, internal pressure, and radius
What is the yearly maximum for radiation exposure? How does this change if someone is pregnant?
Yearly Max Exposure = 5 rem
-eye and thyroid are most susceptible to injury
Pregnant Yearly Max Exposure = 0.5 rem or 0.05 rem/month for the fetus
-fetus is most susceptible to injury
What are 3 ways to protect yourself from radiation exposure?
Distance – minimum safe distance is 6ft
Duration
Shielding
How can we apply the inverse square law to radiation exposure?
The amount of exposure is inversely proportional to the square of the distance of the source
Intensity = 1 / Distance^2
Can quantify the amount of exposure at two different locations with the following equation:
Intensity1 = Distance2^2
Intensity 2 = Distance1^2
What is boiling point, and how is it affected by atmospheric pressure?
The temp at which a liquid’s vapor pressure equals atmospheric pressure
Increased P atm –> Increased boiling point (ex. hyperbaric O2 chamber)
Decreased P atm –> Decreased boiling point (ex. high altitude) –> Increased
What is specific heat?
The amount of heat required to increase the temp of 1g of a substance by 1*C
What is vapor pressure?
In a closed container, molecules from a volatile liquid escape the liquid phase and enter the gas phase –> the molecules in the gas phase exert pressure on the walls of the container (vapor pressure)
What is latent heat of vaporization? Apply this to an anesthetic vapor inside of a vaporizer
Latent heat of vaporization = # of calories required to convert 1g of liquid vapor w/o a temp change in the liquid
- anesthetic liquid in the vaporizer exerts a vapor pressure inside the vaporization chamber (means some of the agent exists as a liquid, and some exists as a gas)
- fresh gas flows over the anesthetic liquid, carrying away some of the agent that exists in the gas phase
- this cools the remaining liquid, which reduces vapor pressure of the liquid (fewer anesthetic molecules that enter the gas phase)
- net result is a decrease in the vaporizer output
*Modern vaporizers compensate for this temp change
What is the Joule-Thompson effect in the context of gas cylinders?
Joule-Thompson Effect: a gas stored at high pressure that is suddenly released escapes from its container into a vacuum – quickly loses speed as well as a significant amount of kinetic energy resulting in a fall in temperature
-explains why an O2 cylinder that is opened quickly feels cool to the touch
What is an adiabatic process?
Describes a process that occurs without gain or loss of energy (heat)
Ex: a very rapid expansion or compression of a gas where there is no transfer of energy
What is critical temperature, and how does this apply to gas cylinders?
Critical Temp = highest temp where a gas can exist as a liquid (the temp above which a gas can’t be liquefied regardless of the pressure applied to it)
-critical temp for N2O = 26.5C – explains why it primarily exists as a liquid inside the cylinder
-critical temp for O2 = -119C – explains why it exists as a gas inside the cylinder
*only N20 and CO2 have critical temps above room temperature
**critical pressure = minimum pressure required to convert a gas to a liquid at its critical temperature
What is the formula to convert Celsius to Kelvin? What about Celsius to Fahrenheit?
Celsius to Kevlin and back:
– C = K - 273.15
– K = C + 273.15
Celsius to Fahrenheit and back:
– C = (F - 32) x 5/9
– F = (C x 1.8) + 32
What are the pressure conversion factors?
- ?? atm = ?? mmHg = ?? bar = ?? kPa = ?? cmH20 = ?? lb/inch^2
- ?? mmHg = ?? cmH20
- ?? cmH20 = ?? mmHg
1 atm = 760 mmHg = 1 bar = 100 kPa = 1033 cmH2O = 14.7 lb/inch^2
1 mmHg = 1.36 cmH2O
1 cmH2O = 0.74 mmHg
What is Avogadro’s number?
Says that 1 mole of any gas is made up of 6.023 x 10^23
-a mole of gas is equal to the molecular weight of that gas in grams
-if a molecule is diatomic (O2), you must account for both atoms
What are the 4 mechanisms of heat transfer? Rank them from most to least important
Radiation ~ Infrared (60%)
Convection ~ Air (15-30%)
Evaporation ~ Water Loss (20%)
Conduction ~ Contact (<5%)
What are the 3 stages of intraoperative heat transfer?
Phase 1: heat redistribution from core to periphery – Hour 1 following induction of anesthesia
Phase 2: heat transfer > heat production – Hours 1-5
Phase 3: heat transfer ~ heat production – Hours 5+
What are the consequences of perioperative hypothermia?
Cardiovascular:
- SNS stimulation –> myocardial ischemia/dysrhythmias
- Shifts oxyhbgb dissociation curve left –> decreased O2 available to tissues
- Vasoconstriction + decreased tissue PO2 –> surgical site infection
- Coagulopathy + platelet dysfunction –> increased blood loss
- Sickling of hgbS –> risk of sickle cell crises
Pharmacologic:
- Slowed drug metabolism –> prolonged effects of anesthetic agents
- Increased solubility of volatile agents –> prolonged emergence
What three drugs can be used to treat postop shivering?
-Meperidine (kappa)
-Clonidine (alpha-2)
-Dexmedetomidine (alpha-2)
*shivering increases O2 consumption up to 400-500% – increases risk of myocardial ischemia and infarction
When is hypothermia a good thing?
-Cerebral ischemia (stroke)
-Cerebral aneurysm clipping
-TBI
-Cardiopulmonary bypass
-Cardiac arrest
-Aortic cross-clamping
-Carotid endarterectomy
based on the fact that O2 consumption is reduced by 5-7% for every 1C
In which region of the esophagus should an esophageal temp probe be placed? How doe misplacement affect the reading?
Should be placed in the distal 1/3 - 1/4 of the esophagus (38-42cm past the incisors)
-falsely high if placed too far (in stomach) due to heat created by liver metabolism
-falsely low if placed too proximal due to cool inspiratory gas
What are the three ingredients required to produce a fire? Give an example of each
Fuel – Oxidizer – Ignition Source
-fuel ex: ETT, drapes, surgical supplies
-oxidizer ex: O2, N2O
-ignition source ex: electrosurgical cautery, laser
What are the steps you take during an airway fire?
Steps to Take When Fire is Present:
1. Stop ventilation and remove ETT
2. Stop the flow of all airway gases
3. Remove other flammable material from the airway
4. Pour water or saline into airway
5. If fire isn’t extinguished on the 1st attempt, then use a CO2 fire extinguisher
Steps to Take After Fire is Controlled:
1. Re-establish ventilation by mask – avoid supplemental O2 or N2O
2. Check ETT for damage – fragments may remain in the pt’s airway
3. Perform bronchoscopy to inspect for airway injury or retained fragments
*DO NOT squeeze reservoir bag as you extubate the pt – can create a blow torch effect at distal end of ETT or push debris lower into airway
What color goggles must be worn for each type of laser: CO2, Nd:YAG, Ruby, and Argon?
CO2 = Clear
Ruby = Red
Argon = Amber
Nd:YAG = Green
What are the four degrees of burns? Which require a skin graft?
1st Degree:
-spontaneous healing
-epidermis only
-stinging, tender, and sore
2nd Degree Superficial:
-spontaneous healing
-epidermis –> upper dermis
-very painful
2nd Degree Deep:
-skin graft
-epidermis –> lower dermis
-very painful
3rd Degree:
-skin graft
-complete destruction of epidermis and dermis
-no sensation (nerve endings are obliterated)
4th Degree:
-skin graft
-extends to muscle and bone
-no sensation (nerve endings are obliterated)
What is the rule of 9’s for burns? How does this apply to the adult?
Total body surface area is divided into areas representing 9% (or multiples of 9%) – due to rounding the numbers don’t add up to 100
-Head = 10%
-Arms = 9% each
-Torso = 18%
-Back = 18%
-Legs = 18% each
*concept is important for calculating fluid requirements
How does the rule of 9’s for burns apply to children?
-Head = 19% (9.5% for front and 9.5% for back)
-Arms = 9.5% each
-Torso = 16%
-Back = 16%
-Legs = 15%
**For every year of age >1 year up to 10 years – decrease head surface area by 1% and increase each leg by 0.5%
What are the consequences of the capillary leak that occurs after a burn?
-Increased vascular permeability –> edema formation
-Loss of protein-rich fluid to the interstitial space –> decreased plasma oncotic pressure –> edema formation
-Loss of intravascular volume –> hypovolemia & shock
-Hypovolemia –> hemoconcentration (rising Hgb in first few days suggests inadequate volume resuscitation)
*fluid shifts and edema formation are greatest in the first 12 hours and begins to stabilize by 24 hours – explains why fluid requirements are higher in the first 24 hours following a burn
What is the Parkland formula for resuscitation in burn patients?
First 24 Hours:
-Crystalloid = 4mL LR x %TBSA burned x kg (1/2 in 1st 8hrs then 1/2 in next 16)
-Colloid = None
Second 24 Hours:
-Crystalloid = D5W at normal maintenance rate
-Colloid = 0.5mL x %TBSA burned x kg
What is the Modified Brooke formula for resuscitation in burn patients?
First 24 Hours:
-Crystalloid = 2mL LR x %TBSA burned x kg (1/2 in 1st 8hrs then 1/2 in next 16)
-Colloid = None
Second 24 Hours:
-Crystalloid = D5W at normal maintenance rate
-Colloid = 0.5mL x %TBSA burned x kg
What is an acceptable urine output in a burn patient? Is this different in children or patients who’ve suffered a high voltage electrical injury?
Adult = > 0.5 mL/kg/hr
Child = > 1 mL/kg/hr
High Voltage = > 1-1.5 mL/kg/hr
*myoglobinemia is the result of extensive muscle damage following a high voltage electrical injury
Why is the burn patient at risk for abdominal compartment syndrome? What is the diagnosis and treatment of this complication?
-May result from aggressive fluid resuscitation
-Intra-abdominal HTN is defined at IAP > 20 mmHg or >12 mmHg AND evidence of organ dysfunction
Treatment:
-neuromuscular blockade
-sedation
-diuresis
-abdominal decompression via laparotomy
What are the clinical considerations for the patient with carbon monoxide poisoning?
-Binds to hemoglobin w/ an affinity 200x that of O2
-Shifts oxyhgb dissociation curve to the left (left = love) – impairs offloading of O2 to the tissues
-Oxidative phosphorylation is also impaired
-Inadequate O2 delivery and utilization causes metabolic acidosis
-Blood takes on a cherry red appearance
-Pulse Ox is NOT accurate (unable to distinguish between HgbO2 and HgbCO)
-SpO2 may give a falsely elevated result
-Treatment includes 100% FiO2 or hyperbaric O2
How is the use of neuromuscular blockers different for burn patients?
Up-regulation of extrajunctional receptors begins after 24 hours:
-SUX is safe within the first 24 hours following the burn, but can cause lethal hyperkalemia after 24 hours
-Dose of NDMRs should be increased 2-3 fold (there are more receptors)
What physiologic changes accompany ECT treatment?
Initial Response: Increased PNS activity during tonic phase (lasts ~15 seconds)
- decreased HR/brady-dysrhythmias
- decreased BP
- increased oral/gastric secretions
Secondary Response: Increased SNS activity during clonic phase (lasts several minutes)
- increased HR/tachydysrhythmias
- increased BP
- increased intragastric pressure
- increased cerebral blood flow
- increased intracranial pressure
- increased intraocular pressure
What are the absolute and relative contraindications to ECT?
Absolute Contraindications:
- recent MI (<4-6 months)
- recent intracranial surgery (<3 months)
- recent stroke (<3 months)
- brain tumor
- unstable cervical spine
- pheochromocytoma
Relative Contraindication:
- pregnancy
- pacemaker/ICD
- CHF
- glaucoma
- retinal detachment
- severe pulmonary disease
*related to an increased SNS response or increased ICP
What is neuroleptic malignant syndrome? Compare it to malignant hyperthermia
Neuroleptic Malignant Syndrome (NMS):
-caused by dopamine depletion in the basal ganglia and hypothalamus from dopamine antagonists or withdrawal from dopamine agonists
-treatment: bromocriptine, dantrolene, supportive care, ECT
Compare to MH:
-NMS = no genetic link –> MH = genetic link
-NMS = Does not develop acutely –> MH = develops acutely
-NMS = associated w/ Psychiatric Med –> MH = not associated
-Both have muscle rigidity, hyperthermia, tachycardia, acidosis
-Treat both w/ dantrolene
-NMS = neuromuscular blockers cause paralysis –> MH = they do not cause paralysis (cause of rigidity is beyond the NMJ)
What is the etiology of serotonin syndrome? What drug interactions with SSRIs increase the risk of developing it?
Occurs when there’s excess 5-HT activity in the CNS
Key drug interactions that increase the risk of serotonin syndrome include an SSRI and:
-Meperidine
-Fentanyl
-Methylene blue
What are the determinants of intraocular pressure? What’s the normal value?
Intraocular Perfusion Pressure = MAP - IOP
-the globe is relatively non-compliant –> IOP is determined by the choroidal blood volume, aqueous fluid volume, and extraocular muscle tone
-Normal IOP = 10-20 mmHg
-aqueous humor is produced by the ciliary process (posterior chamber)
-aqueous humor is reabsorbed by the canal of Schlemm (anterior chamber)
What factors increase intraocular pressure?
-hypercarbia
-hypoxemia
-increased CVP
-increased MAP
-laryngoscopy/intubation
-straining/coughing
-SUX
-N2O (if SF6 bubble in place)
-trendelenburg and prone position
-external compression by facemask
What factors decrease intraocular pressure?
-hypocarbia
-decreased CVP
-decreased MAP
-volatile anesthetics
-N2O
-NDMRs
-propofol
-opioids
-benzos
-hypothermia
What is the difference between open and closed angle glaucoma?
Open-Angle: caused by sclerosis of the trabecular meshwork – impairs aqueous humor drainage
Close-Angle: caused by a closure of the anterior chamber – creates a mechanical outflow obstruction
*Glaucoma is caused by a chronically elevated IOP that leads to retinal artery compression
*IOP is reduced by drugs that reduce aqueous humor production or facilitate aqueous humor drainage (causes miosis)
Which drugs reduce aqueous humor production? Which increase aqueous humor drainage?
Decrease Aqueous Humor Production:
- Acetazolamide (inhibits carbonic anhydrase)
- Timolol (non-selective beta antagonist)
Facilitate Aqueous Humor Drainage:
- Echothiophate (irreversible cholinesterase inhibitor) – promotes drainage via the canal of Schlemm
*can prolong the duration of SUX and ester-type local anesthetics
What is strabismus correction? What unique considerations apply to the anesthetic management of these patients?
Corrects the misalignment of the extraocular muscles and re-establish the visual axis
Key Considerations:
-increased risk of PONV
-increased risk of activating the oculo-cardiac reflex (afferent CN 5 + efferent CN 10)
What is a TAP block? Which patient populations benefit from one?
Transverse Abdominal Plane Block (TAP): unilateral peripheral nerve block that targets the nerves of the anterior and lateral abdominal wall
-best suited for abdominal procedures (general, GYN, and URO) that involve the T9-L1 distribution
-bilateral TAP blocks are required for a midline incision or laparoscopic surgery
What is the anatomy and landmarks used to preform a TAP block?
Abdominal Wall Structures Superficial to Deep:
-SubQ Tissue –> External Oblique –> Internal Oblique –> Transverse Abdominis –> Peritoneum
*local anesthetic placed between internal oblique and transverse abdominis
TAP Block Landmarks: Form the Triangle of Petit:
-External oblique muscle
-Latissimus dorsi muscle
-Iliac crest
Define and give an example of the following:
-Allodynia
-Dysesthesia
-Neuralgia
Allodynia: pain due to a stimulus that does not normally produce pain (ex: Fibromyalgia)
Dysesthesia: abnormal and unpleasant sense of touch (ex: burning sensation from diabetic neuropathy)
Neuralgia: pain localized to a dermatome (ex: herpes zoser (shingles))
What is the defining characteristic between type I and type II complex regional pain syndrome?
Type I (reflex sympathetic dystrophy)
Type II (causalgia)
Complex regional pain syndrome is characterized by neuropathic pain with autonomic involvement
Key distinction = Type II CRPS is always preceded by nerve injury (Type I is not)
What is a thoracic paravertebral block? What is it used for?
-Local anesthetic injected into the paravertebral space (potential space) targets the ventral ramus of the spinal nerve as it exits the vertebral foramen
-Creates a unilateral sensory and sympathetic block along that specific dermatome
-Think of it as a single shot, unilateral epidural block
-Have to perform one block at each dermatome to be anesthetized
*Provides analgesia for breast surgery, thoracotomy, and rib fracture
What structures are anesthetized by a celiac plexus block? How about a superior hypogastric block?
Celiac Plexus Block:
- useful for pain from the upper abdominal organs (not the pelvic organs)
- useful in cancer patients
(celiac plexus innervates the upper abdominal viscera except left side of colon)
Superior Hypogastric Plexus Block:
- useful in patients with pain involving the pelvic organs
- useful in cancer patients
(superior hypogastric plexus innervates the pelvic organs)
Which regional techniques are used to release post-dural puncture headache? (2)
Epidural blood patch
Sphenopalatine block
What is the antibiotic of choice to treat MRSA? What are the special considerations for the administration of this antibiotic?
Vancomycin
-to reduce histamine release and hypotension – administer at a rate of 10-15 mg/kg over 1 hour
-histamine response can be minimized by diphenhydramine 1mg/kg + cimetidine 4 mg/kg 1 hour before anesthesia
What are the functions of the 5 types of white blood cells? (Neutrophils, Basophils, Eosinophils, Monocytes, Lymphocytes)
Neutrophils: fight bacterial and fungal infections (60% of all WBCs)
Basophils: release histamine, serotonin, heparin, and bradykinin; essential component of hypersensitivity reactions; epi prevents degranulation (release of intracellular contents) by binding to beta-2 receptors on the cell membrane
Eosinophils: defend against parasites
Monocytes: phagocytosis, release cytokines, and present pieces of pathogens to T-lymphocytes
Lymphocytes:
-B –> humoral immunity (produce antibodies)
-T –> cell-mediated immunity (does not produce antibodies)
What are the symptoms of anaphylaxis? (CV, resp, skin, GI)
CV: hypotension, tachycardia, arrhythmia, cardiac arrest
Respiratory: bronchospasm (decreased ETCO2, decreased SaO2, increased PIP), laryngeal edema (increased mucus production)
Skin: flushing, urticaria (hives), erythema, pruritus
GI: abdominal cramping, N/V, diarrhea
What hypersensitivity reactions stimulate the H1 and H2 receptors and what are their effects?
Cause:
-Anaphylaxis (requires prior sensitization or cross-reactivity)
-Anaphylactoid Reaction (no prior exposure needed)
H1 Receptor Effect:
-vasodilation
-increased vascular permeability
-smooth muscle contraction (not vascular)
H2 Receptor Effect:
-cardiac stimulation (tachycardia)
-gastric acid secretion
*arachidonic acid metabolites = leukotrienes and prostaglandins (cause bronchoconstriction and vasodilation)
What is the pathophysiology of the 4 types of hypersensitivity reactions? List an example of each
Type 1: Immediate Hypersensitivity
-antigen + antibody interaction in pt who has been previously sensitized to the antigen
-ex = Anaphylaxis, Extrinsic Asthma
Type 2: Antibody-mediated
-IgG and IgM antibodies bind to cell surface or extracellular regions
-ex = ABO-incompatibility, Heparin-induced thrombocytopenia
Type 3: Immune Complex-Mediated
-immune complex is formed and deposited into the patient’s tissue (normally, these complexes are cleared from the body)
-ex = snake venom reaction, protamine induced vasoconstriction
Type 4: Delayed
-allergic reaction is delayed at least 12 hours following exposure
-ex = contact dermatitis, graft-vs-host reaction, tissue rejection
What is the treatment for intraop anaphylaxis?
-Discontinue the offending agent
-Airway support (increase FiO2 and provide airway support)
-Epi (start w/ 5-10 mcg IV for hypotension and 0.1-1mg IV for CV collapse)
-Liberal IV hydration (Crystalloid 10-25 mL/kg or Colloid 10 mL/kg)
-H1-Receptor antagonist (Diphenhydramine 0.5-1 mg/kg IV)
-H2-Receptor antagonist (Ranitidine 50 mg IV or Famotidine 20mg IV)
-Hydrocortisone 250 mg IV (prevents delayed release or inflammatory compounds – not an immediate effect)
-Albuterol for bronchospasm
-Vasopressin for refractory hypotension (start at 0.01 unit/min)
What are the three most common causes of intraop anaphylaxis?
- Neuromuscular Blockers (SUX is most common)
- Latex
- Antibiotics
What patients are high-risk for latex allergy?
-Spina bifida/myelomeningocele
-Atopy
-Health care workers
-Food allergy to banana, kiwi, mango, papaya, tomato
Explain the “chemo man”
What are the five most important GI hormones? What is the key function of each?
Gastrin: increases stomach acid/stimulates chief cells to secrete pepsinogen (pepsinogen is converted into pepsin in presence of stomach acid)
Secretin: tells pancreas to secrete bicarb and the liver to secrete bile
Cholecystokinin: tells pancreas to release digestive enzymes and gallbladder to contract
Gastric Inhibitory Peptide: slows gastric emptying and stimulates pancreatic insulin release
Somatostatin: universal “off” switch for digestion
What is gastric barrier pressure? Why is it important?
Barrier Pressure = LES pressure - Intragastric pressure
-likelihood of gastroesophageal reflux is determined by barrier pressure
-higher the barrier pressure the lower the likelihood of reflex
What are the 3 most important inputs to the vomiting center? What receptors are involved in each one?
Vomiting Center resides in nucleus tractus solitarius (medulla)
Sensory Input arises from:
1. Chemoreceptor Trigger Zone (receptors: 5-HT3, NK-1, DA-2, Noxious chemicals)
2. Vestibular Apparatus (receptors: H1, M1)
3. GI Tract (Vagus n.) (receptors: 5-HT3, NK-1)
What is the mechanism of action of NK-1 antagonists? Give an example
Block substance P in the chemoreceptor trigger zone
Ex: Aprepitant
What are the patient risk factors for PONV?
-Female
-Nonsmoker
-Hx of motion sickness
-Previous episodes of PONV
-Age is loosely associated (youth > elderly)
What are the surgical risk factors for PONV?
-Long surgical duration (>1hr)
-GYN procedures
-Laparoscopy
-Breast
-Plastics
-Peds Procedures (strabismus, orchiopexy, T&A)
What are the anesthetic risk factors for PONV?
-Halogenated anesthetics
-Nitrous oxide (>50%)
-Opioids
-Etomidate
-Neostigmine
What two antiemetics prolong the QT interval?
Droperidol
Ondansetron
What are the two contraindications for metoclopramide?
As a Dopamine Antagonist –> contraindicated in pt with Parkinson’s disease
As a Prokinetic Agent –> contraindicated in pt with a bowel obstruction
How long must the tourniquet remain inflated after a Bier block? Why?
At least 20 min after LA is injected
Premature release increases risk of seizure and/or cardiac arrest
*Upper Extremity: 250 mmHg or 100 mmHg over SBP
*Lower Extremity: 350-400 mmHg or 2x over SBP
What physiologic changes accompany tourniquet deflation?
Tourniquet release stresses the body by:
-restoring blood flow to the extremity produces a relative decrease in circulating blood volume
-products of cellular hypoxia enter the systemic circulation
Releasing the tourniquet produces transient changes that include:
-increased EtCO2
-decreased core body temp
-decreased BP
-decreased SvO2 (SaO2 is usually normal)
-metabolic acidosis
What role does the cyclooxygenase enzyme have in the arachidonic acid cascade? List examples of non-selective COX inhibitors and COX-2 selective inhibitors
COX-1 is always present
-maintains normal physiologic function
-inhibition impairs platelet function, causes gastric irritation, and reduces rental blood flow
COX-2 is not always present
-expressed during inflammation
-inhibition produces analgesic, anti-inflammatory, and antipyretic effects (unlike opioids, there is a ceiling effect to analgesia)
*Non-selective COX inhibitors: ASA, ibuprofen, naproxen, ketorolac, diclofenac, indomethacin
*COX-2 selective inhibitors: Celecoxib, any drug with -coxib
What is Samter’s triad? Why is it important?
Samter’s Triad = Aspirin exacerbated respiratory disease
-refers to the combination of asthma, allergic rhinitis, and nasal polyps
Patients can develop life-threatening bronchospasm following aspirin administration
What are the 4 herbal supplements that increase bleeding risk?
-Garlic
-Ginger
-Ginko biloba
-Saw palmetto
What two herbal supplements reduce MAC?
Kava Kava
Valerian
Chronic ingestion of which herbal medication can mimic Conn’s syndrome?
Licorice
What is the modified Aldrete scoring system?
Used to assess readiness for PACU discharge
Score 0-2 is awarded in 5 areas:
-Activity
-Respiration
-Circulation
-Consciousness
-Oxygen Saturation
*score of 9 or more is generally accepted as discharge ready
What is the difference between Android and Gynecoid obesity?
Android Obesity (Apple Shape):
- more common in men
- characterized by central or abdominal visceral fat accumulation
- increased risk of ischemic heart disease, HTN, dyslipidemia, insulin resistance, and death
Gynecoid Obesity (Pear Shape):
- more common in women
- characterized by gluteal and femoral fat accumulation
- metabolically inactive and is primarily used for energy storage (unlike abdominal fat that is metabolically active)
- increased risk of joint disease and varicose veins
- associated with a reduced incidence of non-insulin dependent DM
What are the diagnostic indicators for metabolic syndrome?
Must have at least 3 of the following:
-large waist circumference (men > 40in & women >35in)
-triglycerides >150 mg/dL
-high density lipoprotein (HDL) <40 mg/dL for men & <50 mg/dL for women
-blood pressure >130/85
-fasting glucose >110 mg/dL
*50-60% greater risk of CV disease than the general population
What are the BMI’s for each class of obesity?
Underweight - BMI <18.5
Normal - BMI 18.5-24.9
Overweight - 25-29.9
Obesity Class I - 30-34.9
Obesity Class II - 35-39.9
Obesity Class III - >40
How can you classify obesity in children?
Overweight = 85th - 94th percentile
Obese = 95th - 98th percentile
Severely Obese = 99th percentile
What is the formula for BMI?
BMI = Weight (kg) / Height (m^2)
**be aware of units
How can you calculate ideal body weight for men and women?
Men (kg) = Height (cm) - 100
Women (kg) = Height (cm) - 105
How does obesity create a restrictive ventilatory defect?
Lung inflation is inhibited due to:
-chest fat compressing the rib cage and hindering its outward expansion
-abdominal fat shifts the diaphragm cephalad and compresses the lungs
-kyphosis and lordosis develop over time and alter the geometry of the ribcage
*extra weight on the chest increase the WOB
How does obesity affect respiratory gas tensions?
Fat is a metabolically active organ, so these pts have an increased oxygen consumption and CO2 production –> minute ventilation must be increased to maintain normal blood gas tensions
While obese pt may experience hypoxemia, PaCO2 is usually normal –> explained by the high diffusing capacity of CO2 and the favorable characteristics of the CO2 dissociation curve (elevated PaCO2 signals impending resp failure)
How does obesity affect FRC? How about the other lung volumes and capacities?
FRC is inversely proportional to BMI:
-reduction in FRC (due to decrease in ERV) below closing capacity creates a situation where distal airway collapse occurs during tidal breathing –> leads to V/Q mismatch, shunt, and hypoxemia (and increased dead space)
-general anesthesia causes FRC to fall by 50% (non-obese ~20%)
-higher O2 consumption coupled w/ smaller FRC predisposes rapid desaturation during apnea
How can you reduce atelectasis in the morbidly obese patient who is mechanically ventilated?
Keep FiO2 <80% during anesthetic maintenance to prevent absorption atelectasis
To Recruit Collapsed Alveoli:
-recruitment maneuver (valsalva)
-PEEP or CPAP 5-10 cmH2O to keep open – improved FRC, V/Q matching, and arterial oxygenation
How does obesity impact the cardiovascular system?
Expansion of intravascular blood volume and high CO state are key changes that lead to the CV complications of obesity
-proliferation of adipocytes requires vasculature growth (requires increased blood volume and CO)
-increased SV is responsible for increased CO
-larger vascular network, blood volume, and O2 consumption place higher workload on myocardium
-venous return must match CO –> heart dilates to accept larger incoming volume (hypertrophy as well to compensate for increased wall stress) –> causes diastolic dysfunction and eventually systolic dysfunction (biventricular HF)
-HTN is the result of hyperinsulinemia, SNS, and RAAS activation, as well as elevated cytokine concentration in the plasma
What EKG changes can accompany obesity?
-Low Voltage (increased distance between heart and leads)
-Left axis deviation (stomach pushes hear up and left)
-Right axis deviation (RV hypertrophy from OSA and volume overload)
-QT prolongation (increased risk of sudden death)
-Ischemia (O2 supply and demand mismatch)
-Dysrhythmias (caused by fatty infiltration of conduction system, myocardial hypertrophy, hypoxemia, hypercarbia, obesity hypoventilation syndrome, and ischemic heart disease)
What valvular defect is highly suggestive of pulmonary hypertension in the obese patient?
presence of tricuspid regurgitation on TEE
What factors affect volume of distribution in the obese population?
-Increased blood volume (requires higher dose to achieve a given plasma concentration)
-Increased CO (faster drug delivery to vessel rich group)
-Altered plasma protein binding (altered free fractions available)
-Lipid solubility of the drug (large fat mass greatly increased Vd for lipophilic drugs)
*remember fat mass AND muscle mass increase –> Vd for water-soluble drugs will increase some because plasma volume is larger but the Vd for fat-soluble drugs will increase a while lot more
How does obesity impact your selection of inhaled anesthetic agents?
-MAC is not changed by obesity
-Volatile agents are lipophilic –> agents with the lowest blood:gas coefficient should be used
-Sevo or Des provide a faster emergence than iso or propofol
-N2O is generally avoided because it restricts the max FiO2 that can be delivered
How does obesity affect the dosing of propofol?
Loading dose is based on lean body weight (because its offset is caused by redistribution and not clearance)
Induction = LBW
Maintenance = TBW
How does obesity affect the dosing of SUX?
Induction = TBW
-even though it is water-soluble – exception to the rule for water-soluble drugs
-the combination of increased blood volume and increased pseudocholinesterase activity (increased clearance) necessitates a TBW dose to be given
How does obesity affect the dosing of NDMRs?
Roc/Vec = LBW for both induction/maintenance
*distributed throughout body water
Cis/Atracurium = TBW (induction) and TBW or LBW (maintenance)
How does obesity affect the dosing of opioids?
Fent/Sufenta = loading dose: TBW – maintenance: LBW
*due to fat solubility and large Vd
Remi = LBW (both loading/maintenance)
*rapidly cleared by plasma esterases
How does obesity affect the dosing of an epidural?
Engorgement of epidural veins and increased epidural fat content will cause greater spread of LA in the epidural space
Dose should be reduced to 75% of the normal dose
What is classified as hypopnea?
50% reduction in airflow for 10 seconds, 15 or more times per hour
-linked to snoring and decreased O2 saturation
What is the pathophysiology of OSA?
OSA = cessation of airflow for at least 10 seconds (apnea) w/ 5 or more unsuccessful efforts to breathe (obstruction) and a greater than 4% reduction in SaO2
Sleep –> Decreased upper airway tone –> Increased upper airway resistance –> Obstruction (snoring) –>Hypoxemia/Hypercarbia (ANS stimulation: systemic HTN, cardiac dysrhythmias, myocardial ischemia, pulm HTN, HF) –> Arousal (daytime somnolence) –> Increased upper airway tone –> Patient breathes
What is the definitive test for OSA? What does it measure? How do you interpret the findings?
Definitive Test = Polysomnography
-calculates the apnea-hypopnea index (AHI)
AHI = # of Episodes of Apnea/Hypopnea / Hours of Sleep
OSA Classification:
-Mild = 5-15 episode/hr
-Moderate = 15-30 episode/hr
-Severe = >30 episode/hr
What is the best bedside tool to identify undiagnosed OSA? How do you interpret the findings?
STOP-BANG scoring system
High Risk = 3 or more questions answered yes
Low Risk = less than 3 questions answered yes
S: snoring
T: tiredness
O: observed apnea
P: pressure (high BP)
B: BMI >35
A: age >50
N: neck circumference >40 cm
G: gender (male)
What is obesity hypoventilation syndrome? How do you identify a pt with it?
Long-term consequence of untreated OSA – over time resp center in the medulla fails to respond to hypercarbia appropriately
Presentation = episodes of apnea during sleep WITHOUT any respiratory effort
Diagnostic Criteria:
-BMI >30
-Awake PaCO2 >45
-Dysfunctional breathing during sleep
Signs: obesity, hypersomnolence during the day, hypoxemia, hypercarbia, resp acidosis, compensatory metabolic alkalosis, polycythemia, pulm HTN
*Also called Pickwickian Syndrome
What are the most common signs of an anastomotic leak following gastric bypass?
- Unexplained tachycardia (most sensitive - 72%) – HR >120 bpm should be a red flag
- Fever (63%)
- Abdominal Pain (54%)
*Ketorolac increases incidence – avoid in periop period
What is Ma huang? What are the complications of its use?
Natural source of ephedrine – indirect-acting adrenergic agonist and thermogenic agent
-any drug interactions that would occur w/ ephedrine apply here
-complications of adrenergic overstimulation (HTN, CVAs, seizures, and death)
What is Orlistat? What are the complications of its use?
Lipase inhibitor that reversibly binds to lipase and hinders the absorption and digestion of consumed fats
-since fat and the vitamins it contains (D, A, K, E) are not absorbed by the gut, they must be supplemented orally
-insufficient quantities of Vit K will impair synthesis of clotting factors 2, 7, 9, and 10 (may cause coagulopathy)
How does Trendelenburg position affect the distribution of blood volume, MAP, and venous pressure?
Blood shifts toward the central circulation –> increased venous return (increased position on Frank-Starling curve) –> careful with HF
MAP stays the same or increases (although venous return initially increases, it is followed by vasodilation and a slower HR)
Venous pressure increases –> hydrostatic pressure (edema of face, eye, and airway); intracranial HTN
Which positions increase the risk of postop airway edema? How can you assess the severity of this complication?
-Prone and Trendelenburg (increased hydrostatic pressure)
-Sitting (neck flexion impairs venous drainage from head)
Assess severity by performing a leak test to assess for air movement around the ETT while pt is spontaneously breathing or inspect the larynx with direct laryngoscopy
How is the brachial plexus susceptible to stretch and compression injury?
Stretch Injury: occurs because brachial plexus is anatomically fixed at two locations (cervical vertebrae and axillary fascia)
-risk is highest when arms are ABducted >90 degrees and/or head is rotated to one side
Compression Injury: occurs when the brachial plexus is compressed as it passes between the clavicle and first rib or by an external force (i.e. shoulder brace/bean bag)
How do you assess a patient for thoracic outlet syndrome? Which surgical position increases the likelihood of it?
Thoracic Outlet Syndrome = blood vessels or nerves in the space between your collarbone and your first rib (thoracic outlet) are compressed
- During preop interview, ask the patient to clasp their hands behind their head – if they complain of pain, this may suggest an increased risk of thoracic outlet syndrome (may be prudent to tuck the arms while in prone position)
- More likely to occur in any position where arms are placed over the head (prone)
What is the most commonly injured peripheral nerve? Who is risk for this injury?
Ulnar Nerve – (not always caused by intraop positioning)
Risk Factors:
-male gender (especially if <50 yo)
-preexisting ulnar neuropathy
-extremes of body habitus (very thing or obese)
-prolonged hospital stay/bedrest
What is the presentation of ulnar nerve injury?
-Impaired sensation of the 4th and 5th digits
-Inability to ABduct or oppose the pinky finger
-Chronic injury presents with claw hand (muscular atrophy)
Which type of nerve injury provides a greater risk for long term injury (sensory or motor)?
Sensory deficits are more common, less serious, and tend to resolve on their own (usually 5 days or less)
Motor deficits are less common and more serious
What are the causes of median nerve injury?
-IV placed in AC
-Carpel tunnel syndrome
-Elbow hyperextension
-Forced elbow extension during positioning after a neuromuscular blocker has been administered
What is the presentation of a median nerve injury?
Reduced sensation over palmar surface of the thumb, index finger, middle finger, and lateral aspect of the ring finger
Unable to oppose the thumb (chronic injury can lead to the ape hand deformity)
What are the causes of radial nerve injury?
-External compression by IV pole
-Excessive cycling of the NIBP cuff
-Upper extremity tourniquet
-Sheets that are too tight (if arms are tucked)
What is the presentation of radial nerve injury?
Wrist Drop
-inability to extend the hand at the wrist
What is the etiology, presentation, and prevention of obturator nerve injury?
Etiology:
-excessive flexion of thigh towards the groin
-excessive traction during lower abd surgery
-forceps delivery
Presentation:
-inability to ADDuct the leg
-reduced sensation over the medial aspect of the thigh
Prevention = minimize hip flexion
What is the etiology, presentation, and prevention of femoral nerve injury?
Etiology: excessive traction during lower abdominal surgery
Presentation: impaired knee extension and hip flexion; reduced sensation over anterior thigh and anteromedial aspect of the leg
Prevention: avoid excessive traction during lower abdominal surgery
What is the etiology, presentation, and prevention of saphenous nerve injury?
Etiology: medial aspect of the leg leans against the supporting cradle in the lithotomy position
Prevention: place padding between leg and stirrup
Presentation: reduced sensation over anteromedial aspect of the leg
What is the etiology, presentation, and prevention of common peroneal nerve injury?
Etiology: Highly susceptible to injury when pt is in stirrups
-nerve wraps around the fibular head, and can be compressed when lateral aspect of the leg leans against the stirrup bar
Presentation:
-foot drop
-inability to evert the foot
-inability to extend the toes dorsally
Prevention:
-place padding between the leg and stirrup
-pad under the fibular head
-knees should be flexed with minimal rotation
What is the etiology, presentation, and prevention of sciatic nerve injury?
Etiology:
-lithotomy –> extreme hip flexion and/or external rotation of the legs
-sitting –> straight legs
Presentation: foot drop
Prevention:
-ample padding under buttocks
-avoid excessive external rotation of the hips
Which position is most likely to cause compartment syndrome?
Lithotomy Position
- it is associated with increased leg compartment pressure, and raising the legs above the heart reduces lower extremity perfusion pressure
- this sets the stage for leg ischemia –> edema –> more ischemia –> more edema –> etc..
*can progress to rhabdomyolysis and/or reperfusion injury
Which position is most likely to cause venous air embolism?
Sitting
-Venous air embolism –> right heart –> pulmonary vasculature –> increased dead space & increased RV workload
-Paradoxical air embolism –> right heart –> patient foramen ovale –> left heart -> systemic circulation –> stroke
*can occur in any position that produces a pressure gradient between the atmosphere and the veins at the surgical site
What position is most likely to cause midcervical tetraplegia?
Midcervical Tetraplegia: associated w/ hyperflexion of the neck (chin to chest) –> ischemia occurs as a result of stretching and/or compression of the midcervical spinal cord (usually C5)
Most common in the sitting position
-place at least 2 fingers in-between the chin and chest
What is the purpose of a positioning device for a patient in the prone position?
Positioning device = chest rolls, Wilson frame, or Jackson table
Distribute the patient’s weight to the thoracic cage and the boney pelvis – allows abdomen to hang freely (promotes normal diaphragmatic excursion throughout the respiratory cycle)
*if abdomen is compressed – intraabdominal pressure increases, which reduces pulmonary compliance and increases intrathoracic pressure
*venous pressure is also increased – can cause back bleeding via the epidural veins during spinal surgery
What three factors worsen tracheobronchial compression in the patient with an anterior mediastinal mass?
-Supine position
-Induction of general anesthesia
-Positive pressure ventilation
What is the best induction technique for a patient with an anterior mediastinal mass?
Spont ventilation (preserves normal airway distending pressure gradient)
Sitting position
*these minimize but not always prevent compression of the vital chest structures
What is the AANA Code of Ethics?
Dictates the principles of conduct and professional integrity that the decision-making and behavior of nurse anesthetists
Speaks to the anesthetist’s responsibilities as a professional, which hold the individual CRNA accountable for his or her own actions and judgments, regardless of institutional policy or physician orders
What is the difference between practice guidelines and practice standards?
Guidelines are systematically developed statements to assist providers in clinical decision making that are commonly accepted within the anesthesia community
Standards are authoritative statements that describe minimum rules and responsibilities for which anesthetists are held accountable
Guidelines “should” be adhered to – Standards “must” be adhered to
Define autonomy, nonmaleficence, and beneficence
Autonomy: patient’s ability to choose without controlling, interference by others and without limitations that prevent meaningful choices
Nonmaleficence: provider has an obligation not to inflict harm or hurt (Do no harm)
Beneficence: providers should take action for the benefit of others (includes preventing harm and actively helping their patients)
What are the 6 elements of informed consent?
-Competence
-Decision making capacity
-Disclosure of information
-Understanding of disclosed information
-Voluntary consent
-Documentation
What 4 things must be proven in a lawsuit asserting malpractice?
-Duty
-Breath of duty
-Causation
-Damages
What is res ipsa loquitur?
“The things speaks for itself” – can shift the burden of proof from the plaintiff to the defendant
Can occur if the following conditions can be established:
1. injury would not have occurred in the absence of negligence
2. injury was caused by something under the complete control of the defendant (provider)
3. patient did not contribute in any way to the injury
4. evidence for the explanation of events is solely under the control of the provider
What is the difference between libel and slander?
Libel = defamation in the written form
Slander = defamation in the verbal form
What is the difference between assault and battery?
Assault = attempt to touch another person
Battery = touching a person without either expressed or implied consent
What is Emergency in Medical Treatment and Active Labor Act?
Ensure public access to emergency services regardless of their ability to pay
-imposes specific obligation on Medicare-participating hospitals that offer emergency services to provide a medical screening examination when a request is made for examination or treatment for an emergency medical condition (EMC) regardless of an individual’s ability to pay
What is a schedule II drug? list examples
High potential for abuse potentially leading to dependence
Ex:
-opioid agonists (fentanyl, morphine, hydromorphone, etc)
-cocaine
-methamphetamine
-phencyclidine
What is the OSHA limit for occupational exposure to ionizing radiation?
Annual = 5 rem
Lifetime = (age in years - 18) x 5 rem
What are some typical behaviors of the imparied provider?
-Frequent and unexplained tardiness, absences, or illnesses often with elaborate excuses
-Poor performance w/ errors, accidents, or injuries that are inadequately explained
-Confusion, memory loss, difficulty concentrating or recalling details
-Severe mood swings, changes in personality
-Visibly intoxicated
-Refuses drug testing
-Track marks, bloodshot eyes, significant weight loss or gain
What should you do if you suspect a fellow anesthesia provider is impaired?
-Do not let the person out of your site, and do not let them drive
-Have a bed in a treatment facility available
-Do not let the impaired person decide their treatment
-Only when all else fails, threaten to call the police
What are the 6 elements of high-quality care?
- Patient centered
- Safe
- Effective
- Timely
- Efficient
- Equitable
