ITE Pulm Flashcards
Cormack-Lehane system
- Grade 1
Complete glottis visible
Cormack-Lehane system
- Grade 2b
Anterior glottis not visible.
Only posterior arytenoids and epiglottis visible.
Cormack-Lehane system
- Grade 3
Epiglottis, but not glottis is visible
Cormack-Lehane system
- Grade 4
Epiglottis is not visible
First line treatment for asthma exacerbation in OR
- bronchospasm
- airway inflammation
- mucous plugging
100% FIO2
then deepen the anesthetic
*Beta agonists can worsen oxygenation d/t changes in V/P mismatch
Inhaled corticosteroids for asthma treatment take ____ (time) to see significant changes
6-12 hours
- treat inflammatory component
Heliox is a ____ andis a useful adjunct in that it helps to decrease the density of delivered gases (ie: Beta2 agonists and steroids get past obstruction), resulting in less pt effort needed to get the same volume of gas.
mixture of 70% helium and 30% oxygen
How does giving a beta-2-agonist in pts having a bronchospasm worsen the oxygenation?
d/t changes in V/P mismatch
- The under-ventilated alveoli will have concomitent pulmonary vasoconstriction to decrease the amount of shunting
- When B2-agonist is used, some bronchodilation occurs, but inflammation and mucous plugging continues
- there is increased perfusion to poorly ventilated lung units -> V/Q mismatch
Bronchospasm affects ____ muscle, and nondepolarizing relaxants affect ____ muscle
smooth
skeletal
________ block occurs in 100% of patients undergoing interscalene blockade, even with dilute solns of local anesthetics and results in a ___% reduction in pulmonary function
Ipsilateral phrenic nerve block
- results in diaphragmatic paresis
Most common level for placement of interscalene block
Between Anterior and middle scalene m
- at the cricoid cartilage or C6 vertebrae lvl
- Where the cervical n roots C5-6 leave the spine
The interscalene block may spare the ____ nerve.
ulnar nerve.
Intraarterial injection of local anesthetics would cause what type of symptoms?
CNS symptoms
immediate sz
intrathecal injection of massive amts of local anesthetics would cause what type of symptoms?
total spine
LOC +
respiratory insufficiency/apnea
Foreign body in children display signs of ______, while adults often display signs of ______
Children
- air trapping: hyperinflation with obstructive emphysema
Adults
- atelectasis
Two most feared complications of mediastinal mass in anesthesia
- Complete airway obstruction w/ inability to maintain gas exchange
- Cardiovascular collapse from compression of vital structures.
GA approaches to pts with mediastinal mass
- local/regional anesthesia whenever possible
- Awake intubation.
- Secure airway beyond lesion.
- Confirm ability to ventilate and oxygenate
- Have thoracic surgeon in room during induction
- Ensure availability of rigid bronchoscopy if obstruction occurs
______ results in a flow-volume loop with an:
- expiratory phase with a quick peek followed by a much lower than normal plateau phase. *kink
- normal inspiratory phase
- Graph shifts to L
COPD
Assuming full inspiratory and expiratory efforts are made, end INSPIRATION volume is equal to ______, and end EXPIRATION is equal to ____
total lung capacity
residual volume
Examples of intrathoracic airway obstruction and extrathoracic airway obstruction
intrathoracic airway obstruction
- distal tracheal tumor
- mediastinal mass
extrathoracic airway obstruction
- vocal cord paralysis/dysfunction
- proximal tracheal tumor
- glottic strictures
What causes a flow-volume loop with plateaued AND decreased inspiratory and expiratory flows?
Fixed upper airway obstruction or fixed large airway obstruction?
A variable INTRATHORACIC airway obstruction produces a flow-volume loop with a plateaued (inspiratory/expiratory) curve.
expiratory
A variable EXTRATHORACIC airway obstruction produces a flow-volume loop with a plateaued (inspiratory/expiratory) curve.
inspiratory
FEV1/FVC <70% =
FEV1/FVC >80% =
Obstruction in adults
- Low
restrictive
- normal/increased
*80% is normal
Staging of COPD (gold staging)
- FEV1/FVC < 70%
I: mild - FEV1 > 80% predicted
II: moderate - FEV1 50-80%
III: Severe- FEV1 30-50%
IV: very severe- FEV1 <30%
What is vital capacity?
IRV + TV + ERV
What is FRC?
Amount of air in the lungs after normal respiration
ERV + RV
*usually ~ 3000mL
What is the forced vital capacity (FVC)?
Maximal expiration after maximal inspiration
Sulfhemoglobin is a condition caused by irreversible binding of sulfur to the porphyrin ring of heme of hgb. This shifts the oxyhemoglobin dissociation curve to the (right/left).
Right
*opposite of methemoglobinemia: shifts curve to the Left. Methemoglobinemia is less able to be tolerated than sulfhemoglobin. Tx with -methylene blue
Blood color of:
Methemoglobin
Sulfemoglobin
Methemoglobin: chocolate brown
Sulfemoglobin: dark greenish-black
What shifts the hgb dissociation curve to the left? (5)
- fetal hgb
- carboxyhemoglobin
- cold temp
- alkalosis
- decreased 2,3-DPG (ie: pRBC transfusion, septic shock, hypophosphatemia, hypocarbia)
What shifts the hgb dissociation curve to the Right?
- Sickle cell
- pregnancy
- hyperthermia
- acidosis
- increased 2,3-DPG (chronic anemia, CHF)
- Hypercarbia
Alkalosis shifts the oxyhemoglobin dissociation curve to the (Right/Left)
Left
CADET face right! mneumonic
rightward shift of oxyhemoglobin dissociation curve
- Carbon dioxide
- Acidosis
- 2,3-DPG
- Exercise
- Temperature
Diffusing capacity of the lung for carbon monoxide (DLCO) is decreased in _____
pulmonary embolism
- increase in dead space ventilation -> prevents nl amount of carbon monoxide from being absorbed
DLCO is (increased/decreased) in asthma
Increased
- Increased total lung volumes
- Increased expiratory times
- No parenchymal disease
- Increased amount of CO that can be absorbed.
DLCO is (increased/decreased) in exercise
increased
- more blood flow through pulm vessels, more hgb present to bind more CO
DLCO is (increased/decreased) in L->R cardiac shunt
increase
- increased blood volume -> overload of pulm circ -> more CO is abs by more blood passing thru pulm vasculature.
“Double peak” appearance in capnography in pts with_____
COPD w/ single lung transplant
- 1st peak: from normal (transplanted) lung, and second peak is the exhalation from the native, diseased lung)
In capnography, phase 3-4 is the expiratory alveolar plateau, and represents ____.
continued exhalation of CO2 from the lung alveoli
Vital capacity is ?
Maximal amt of air that can fill the lungs and participate in gas exchange
TLC - RV
or
TV+IRV+ERV
Forced vital capacity is?
Amt of gas that can be forcefully and maximally exhaled from a maximal inhaled volume
Both FEV1 and FVC are reduced with (restrictive/obstructive) lung pathology
restrictive
amiodarone is often used for _____ in difficult to control afib or ______
rate control
ventricular arrhythmias
Amiodarone is associated with _____ and _____, especially with the use of supplemental O2 and higher FiO2 concentrations.
pulmonary fibrosis, pneumonitis
3 Drugs known to cause pulmonary toxicity and fibrosis (dry cough, dyspnea on exertion, decrease in DLCO)
- Methotrexate
- Bleomycin
- Amiodarone
B/l recurrent laryngeal nerve injury after thyroid sx can cause _____
loss of function of posterior cricoarytenoid m. (the only muscle that abducts the vocal cords) –> unopposed vocal cord adduction –>respiratory distress and failure
Unilateral recurrent laryngeal nerve injury after thyroid sx can cause _____
unopposed adduction of ipsilateral vocal cord –> difficulty with phonation but not respiratory distress.
B/l superior laryngeal nerve injury after thyroid sx can cause _____
hoarseness and tiring of the voice (no airway compromise)
*superior laryngeal n innervates the cricothyroid membrane
Which West lung zone has the largest dead space ventilation?
West zone 1:
higher alveolar pressure > pulmonary arterial and venous pressure
PA > Pa > Pv
- no pulmonary blood flow in zone 1
- does not exist in human lung except in positive pressure ventilation
Which West lung zone?
PA > Pa > Pv
Pa > PA > Pv
Pa > Pv > PA
(A = alveolar a = arterial v = venous)
Zone 1
Zone 2
Zone 3
Most human lung is comprised of which West lung zone?
Zone 3
Pa > Pv > PA
*most dependent area of the lung
Why do COPD patients have auto-PEEP?
COPD results in loss of elements that keep the lungs open during expiration.
During exhalation, the airways close, resulting in air trapping.
Smoking cessation immediate benefits
- Decrease cyanide levels (improve oxygen use)
- Decrease CO (improve oxygen use)
- Decrease nicotine levels (better vasodilation)
What causes a decrease in FRC?
mneumonic PANGOS
- Pregnancy, ascites, neonates, GA, Obesity, Supine position
More aggressive strategies for preoxygenation before intubation if 100% FiO2 via face mask isn’t enough in a spontaneously ventilating pt?
CPAP or BIPAP
- replace nitrogen with oxygen in lungs, create O2 reservoir.
- Provides PEEP
*HFNC mayyy provide intrinsic PEEP
BVM limitations in pre-oxygenating pts
- Not meant for spontaneously breathing pts
- FiO2 can range from 21%-100%
- Do not allow for high flows > 15LPM
Corticosteroid administration can take ___ hours after the first dose to see any appreciable changes in airway edema
> 12h
Gold standard test for laryngeal edema
nasopharyngeal fiberoptic exam
- need cooperative pts and appropriate equipment
*CT and MRI can image, but not safe if pts can have airway compromise at any moment.
How does racemic epinephrine 50/50 mixture help with airway edema?
- alpha-adrenergic receptor stimulation in airway ->
Mucosal vasoconstriction, decrease amt of fluid present in the airway - beta-adrenergic stimulation in bronchial tissue ->
bronchodilation -> prevent bronchoconstriction
Stridor post-extubation (~30-60min) is often the result of ___________
laryngeal edema
How does CO poisoning cause lactic acidosis?
Formation of CO-hgb –>
less oxygen binding sites and reduction in O2 release –>
decrease O2 delivery to tissues –>
lactic acidosis
*CO binds to hgb < 200x affinity than O2
SaO2 is the ____
PaO2 is the _____
Which one is affected in carbonmonoxide poisoning?
Fraction of Hgb that is saturated with Oxygen
Oxygen tension
Both appear Normal in carbonmonoxide poisoning
Elimination of CO can be shortened from ____ to ____ (time) with the use of 100% supplemental O2
4hours -> 40 min
Methemoglobinemia is d/t the oxidation of iron from the ____ to the ___ form, which leads to the inability of heme to ____
Fe2+ (ferrous) to Fe3+ (ferric) form
bind oxygen –> diminished oxygen content and less oxygen delivery
Important causes of methemoglobinemia (3)
- Benzocaine
- Dapsone
- Inhaled nitric oxide
Difference between OSA and central sleep apnea
- Snoring more common in OSA
- In CSA, there is no effort to breathe during periods of apnea
- CSA is usually secondary to an underlying medical condition (HF, stroke, NM disorders, narcotics, altitude)
- CSA can be treated with medications that stimulate breathing (acetazolamide or theophylline)
Common sx and symptoms between (7)
- Obstructive sleep apnea (OSA)
- Central sleep apnea (CSA)
- Complex sleep apnea
- chronic fatigue
- daytime somnolence
- decreased daytime alertness
- decreased ability to concentrate
- difficulty staying asleep
- mood changes
- morning headaches
Central sleep apnea (CSA)
- what is it?
- how is it diagnosed?
brain respiratory centers do not function properly during sleep. Pts fail to trigger inhalation.
- Apneic period (>10 sec) w/o identifiable respiratory effort
- > 10 episodes / hr of sleep
- Glottic opening is present w/o closure
Obstructive sleep apnea (OSA)
- what is it?
- how is it diagnosed?
- > 5 episodes/hr of complete cessation of airflow during breathing
- Lasting > 10 seconds despite maintenance of neuromuscular ventilatory effort
- SaO2 decrease of at least > 4%
Diagnosis of OSA is made using ____
polysomnography
How does CPAP help OSA?
Positive pressure keeps pts airway open ->
preventing obstruction ->
preventing hypopnea or apnea
How does BIPAP/ASV (adaptive servo-ventilation) help central sleep apnea (CSA)?
Higher inspiratory pressure promotes/assists inspiration
Lower expiratory pressure assists expiration in the absence of active ventilation
Which one can be treated with mediations to stimulate breathing (OSA/CSA)?
CSA
- Theophylline
- Acetazolamide
In a healthy pt breathing RA, PAO2 will be ___ mmHg
100 mmHg
In a healthy pt breathing RA, FiO2 will be ___ mmHg
0.21
Hypoventilation in postop period may result in PaCO2 (increasing/decreasing), and PAO2 (Increasing/decreasing)
PaCO2: increase
PAO2: decrease
What are the tenants of management to help decrease the risk of leakage across the bronchopleural fistula (BPF)? (4)
- End expiratory pressure
- Short inspiratory time
- Low tidal volumes
- Low RR
__________ - Can be achieved with Lung isolation
- Spontaneous ventilation > Positive pressure ventilation
Bronchopleural fistula refers to _____. Ie. from post thoracic surgery on the pulmonary tree, pneumonectomy, lobectomy, malignancy, ARDS, s/p chemo/radiation.
leakage of inspired air from the airways to the pleural space for > 24h
Bronchopleural fistula Acute clinical presentation: (5)
- Sudden purulent sputum
- Subcutaneous emphysema
- Mediastinal/Tracheal shifts
- Tension Pneumothorax
- Dyspnea
Treatment of Bronchopleural fistula if severe and in order of severity (5)
Permissive hypercarbia/Spontaneous ventilation
Chest tube or pleural drain
High frequency ventilation
High frequency jet ventilation
EMCO
High frequency jet ventilation delivers _____ tidal volumes under ____ pressures at frequencies of _____
Small
High
100-200 breaths/min
What is closing capacity?
The capacity during which airway closure begins to occur.
Consists of closing volume and residual volume
*Obesity and positioning has no effect on CC, but does for FRC
Factors that increase closing capacity? (5)
Mneumonic: ACLS: S
- Age
- COPD
- LV failure (CHF)
- Smoking
- Surgery
*All affect transpulmonary pressure across the airways resulting in easier airway collapse at higher lung volumes
Which is harder to place, a single or double lumen tube?
Double lumen tube
- rigid, larger, odd shape, can only be placed orally
*small mouth openings can be challenging
Two most effective methods of isolating the surgical lung?
Double lumen tube and
Bronchial blocker
- Passed through the tube and positioned via fiberoptic scope
__________ with two lung ventilation is the most important predictor of desaturation in pts who transition to one lung ventilation
Arterial PaO2
Pts with obstructive lung diseases have (better/worse) PaO2 during one lung ventilation.
Better
- unknown reason
- Better maintenance of FRC/?
(Right/Left) sided lung surgery is a predictor of desaturation.
Right
- has 10% more volume
- higher chance of increased shunt
Gold standard for analgesia in major upper abdominal surgery or thoracotomies
mid-thoracic epidural anesthesia
Postop pain following major abdominal/intrathoracic surgeries can cause a functional ___________, which decreases inspiratory reserve volume, FVC, and FEV1.
Functional restrictive lung disease
Airway closure begins (earlier/later) in pts with emphysema compared to pts with normal lungs.
Earlier
- loss of supporting structures
In normal lungs, the (dependent/nondependant) lung regions will have small airway closure first.
Dependent
- greater pleural pressure in the dependent lung regions
Airway closure occurs earlier in expiration in older pts bc ______
pleural pressure becomes more positive as age increases..
Airway closure can be seen at or above FRC
Lung resistance can be divided into _____ and ____
Airway resistance
Elastic resistance
__________ resistance affects airflow into the lungs. Peak inspiratory pressure (PIP) directly varies with flow resistance.
Airway resistance
Peak inspiratory pressure (PIP) measures resistance from the ___________ to the _______. It directly varies with ______ resistance.
Ventilator tubing to the segmental bronchi
airflow resistance (airway resistance)
________ resistance affects the expansion of the lungs. It can also be thought of as the pulmonary compliance. When the elastic resistances increases, pulmonary compliance (increases/decreases)
Elastic resistance
Decreases
Changes in elastic resistance causes changes in (peak inspiratory pressure/plateau pressure)
Both
Situations that increase airway resistance (or decrease airflow) will result in increased:
(peak inspiratory pressure/plateau pressure)
- ie: bronchospasm, kinked ET, airway secretions, mucus plug
PIP
*Pplateau remains unchanged
Situations that increase the elastic resistance (or decrease compliance) will result in increased:
(peak inspiratory pressure/plateau pressure)
- Ie: intrinsic pulmonary disease, ascites, abdominal insufflation, tension pneumo, Tburg position
Both peak inspiratory pressure and plateau pressure
What causes Both peak inspiratory pressure and plateau pressure to increase on anesthesia machine?
Situations that increase the elastic resistance (or decrease compliance) will result in increased:
(peak inspiratory pressure/plateau pressure)
- Ie: intrinsic pulmonary disease, ascites, abdominal insufflation, tension pneumo, Tburg position
What causes eak inspiratory pressure to increase but not plateau pressure on anesthesia machine?
Situations that increase the elastic resistance (or decrease compliance) will result in increased:
(peak inspiratory pressure/plateau pressure)
- Ie: intrinsic pulmonary disease, ascites, abdominal insufflation, tension pneumo, Tburg position
Severe peripheral neuropathies such as acute inflammatory demyelinating polyradiculopathy (AIDP), aka Guillain-Barre Syndrome (GBS), will tend to cause:
(restrictive/obstructive) pulmonary dysfunction.
How does this affect FEV1 and FVC?
Restrictive
- phrenic and intercostal nerve involvement -> respiratory muscle weakness and diminished ventilatory capacity, both inspiratory and expiratory efforts
- Once pt is intubated, lung compliance is normal and not restricted. There is no structural issues.
- decrease in both proportionately
Absolute indications for 1 lung ventilation
- Protective isolation of each lung to prevent contamination of healthy lung (abscess)
- Massive hemorrhage control
- Bronchopleural fistula
- Unilateral cyst or bullae
- Trauma
- Unilateral lung lavage
- VATS
- Surgical exposure (Aortic aneurysm, pneumonectomy, lung vol reduction, min invasive cardiac sx , ect)
TEE showing flattened interventricular septum with leftward bulge indicates _____
RV failure and pulmonary hypertension
*Common during induction of one lung ventilation or reperfusion of transplanted lung
Why is RV failure common during induction of one lung ventilation or reperfusion of transplanted lung? How can you initially treat it?
Increased hypoxic vasoconstriction -> increased PVR
Tx: Inhaled nitric oxide ->
decrease shunting and decrease PVR by increasing blood flow in the ventilated lung
- other: avoid hypoxia, hypercarbia, maintain normothermia, avoid acidosis
Effect of milrinone of PVR and systemic vasculature?
Decrease PVR
Increase systemic vasodilation
*can help pulmonary hypertension, but can worsen hypotension
The shift of carbon dioxide dissociation curve occurs d/t the ______
Haldane effect
The process of oxygen binding to hgb and displacing carbon dioxide from the blood is called the _____
Haldane effect
- downward shift of CO2 dissociation curve in physiologic settings with higher oxygen levels (ie. lungs)
- facilitates removal of CO2 from the body
The process in which an increase in CO2 in the blood causes oxygen to be displaced from hgb is called the ______
Bohr effect
- Opposite of haldane effect
- Rightward shift of oxygen-hgb dissociation curve
Boyle gas law
Pressure of a gas is inversely proportional to its volume at a constant temp
Dalton gas law
Total pressure of a gas mixture is equal to the sum pf the partial pressures of the individual gases in the mixture
How does CPAP help COPD?
Positive pressure keeps pts airway open during INSPIRATION (provides necessary pressure to recruit alveoli that collapsed) and EXPIRATION (keeps alveoli open) ->
Increases lung volume and FRC ->
Increases lung compliance and reduces intrapulmonary shunting ->
Improves V/Q mismatch ->
Improves oxygenation
It also reduces surfactant depletion
*CPAP Helps OSA by:
Positive pressure keeps pts airway open ->
preventing obstruction ->
preventing hypopnea or apnea
With CPAP, respiratory rate is _____ and minute ventilation is _____
decreased
Increased
- Minute ventilation is the volume of gas inhaled or exhaled from lungs per min
- Normal min vent at rest is 5-6 L/min
Carboxyhemoglobin level > ___% with neurologic sequelae or cardiac abnormalities is an indication for hyperbaric oxygen therapy
> 25%
Why does paravertebral anesthesia result in less hypotension than thoracic epidural anesthesia?
Unilateral block vs b/l sympathectomy
In a pt with an empyema w/ recent lung resection sx, it is assumed that they have a ____ unless proven otherwise
Bronchopulmonary fistula
- avoid positive pressure ventilation until the lungs are isolated from eachother
- lung isolation is often requested, but not required
On the flow volume loop (aka pressure-volume loop), what does pressure overdistension look like? What does it signal?
“Bird’s Beak”
- Sharp rightward deflection
- Prompt you to reduce driving pressures or delivered tidal volume to prevent volutrauma
On the flow volume loop (aka pressure-volume loop), what does volume overdistension look like?
Sharp upward deflection with increased FRC
In pts with reactive airway disease, use of _____ is the most useful intervention to prevent perioperative bronchospasm during induction
Short acting inhaled beta-adrenergic agonists such as racemic albuterol or levalbuterol -> bronchodilator
What is the diagnosis post pneumonectomy?
- PaO2/FiO2 < 200
- PCWP < 18 mmHg (nl is 12 mmHg)
- B/l infiltrates on chest radiograph
post pneumonectomy pulmonary edema
*PCWP > 18 mmHg is indicative of cardiogenic decompensated HF
Carbonic acid is primarily buffered by ______
deoxyhemoglobin
In metabolic compensation, the kidneys will _____
directly excrete H+ in the proximal tubule
The majority of physiologic buffers are weak (acid/bases)
acids
- bicarbonate
- phosphate
- plasma proteins
*Binds the H+ ions that are produced by the ionization of carbonic acid and prevent a pH change in the serum
The plasma level of CO2 and ____ are in equilibrium. CO2 is primarily eliminated ______, and is buffered by _____ in the blood
carbonic acid
in the lungs
Hemoglobin
Ketorolac is a ______, and can result in a 20% of bronchospasm, so should be avoided in pts with asthma.
Cox-1 and Cox-2 inhibitor NSAID
*ASA can also cause bronchospasm
(Propofol/Sevoflurane) is better at preventing laryngospasm reflex.
Propofol
- thats why you can bolus it if laryngospasm occurs
Alternative to measuring DLCO is _____
PaCO2 and PaO2
- from ABG
- Measurement of gas exchange
DLCO is a measurement of ____. It correlates with ____
adequacy of gas exchange
- The total functioning surface area of the alveolar-capillary interface
*NOT a measure of respiratory mechanics
A DLCO of (greater/less) than 40% is predictive of postoperative respiratory complications
Less than 40%
_________ is a viable therapeutic option in an anemic pt who refuses blood transfusions
Hyperbaric oxygen therapy
What electrolyte abnormalities are present in respiratory and metabolic alkalosis?
Extracellular shift of H+ ions -> Intracellular shifts of cations
- hypocalcemia
- hypokalemia
- hypophosphatemia
The source of hypoxemia in ARDS is _______ caused by diffuse alveolar collapse and atelectasis, and the severity of the syndrome can be characterized by ______
a profound shunt
PaO2/FiO2 ratio
PaO2/FiO2 ratio:
Mild, moderate, severe ARDS criteria
Mild: 201-300
moderate: 100-200
Severe: < 100
Emphysema is characterized by a large:
V/Q mismatch / Shunt
V/Q mismatch
- destruction of alveolar membrane, where gas diffusion occurs
- Large degree of ventilation w/o perfusion
What is the effect of hyperoxia on the systemic and pulmonary vasculature?
Why is hyperoxia bad?
Causes systemic vasoconstriction and pulmonary vasodilation
Increase circulating reactive oxidative stress
When FRC falls below closing capacity, t leads to ______
atelectasis, shunt, hypoxemia
Causes of restrictive lung disease, and ways to differentiate
Intrinsic pulmonary disease
Extrinsic skeletal or muscular disease
CXR
RSI is typically used to lung tranplantation bc ______
Pts are typically non-fasted
- Emergency basis to minimize graft ischemia time
Hypercarbia during lung transplant is ______
not recommended
- worsen pulmonary HTN
In a healthy pt, the peripheral chemoreceptors begin to stimulate respiratory centers in the brainstem when arterial oxygen tension drops below _____
PaO2 of 50 mmHg
aka
arterial oxygen saturation of 85%
_________ are responsible for the hypoxic ventilatory response
Peripheral chemoreceptors
- Carotid bodies
- Aortic bodies
Obese people have (obstructive/restrictive) lung disease.
Their FEV1:FVC ratio is ____
restrictive
> 80%
*80% is normal
Apnea-Hypopnea index
- Normal
- Mild
- Mod
- Severe
- Normal: 0-4
- Mild: 5-14
- Mod: 15-29
- Severe: >30
Clinical markers suggesting need for postop mechanical ventilation
- MG >6 years
- Chronic resp disease
- Pyridostigmine > 750mg/d
- Vital capacity > 2.9L
Why is inhalational induction in cystic fibrosis slower than the general population?
- Increase in FRC
- Small TV
- V/P mismatch
Which inhalational anesthetic is associated with megaloblastic anemia??
Nitrous oxide
- inhibits Vit B12 dependent enzymes
Hepatopulmonary syndrome manifests as hypoxia in the setting of cirrhotic liver disease d/t ______
dysregulation of pulmonary vascular tone
- Inc R to L intrapulmonary shunt and hypoxia that is resistant to increases in FiO2
- Orthodeoxia is classic (arterial desaturation in the standing position which improves in lying supine)
What is the mixed venous oxygen saturation (SvO2)?
marker of tissue oxygen metabolism and provides insight as to whether or not the current cardiac output is meeting the body’s oxygen requirement
mixed venous oxygen saturation (SvO2) is proportional to ____ and inversely proportional to ____
cardiac output
oxygen utilization
Bronchoconstriction is d/t (sympathetic / parasympathetic) stimulation through the ____ nerve
parasympathetic
Vagus
A foreign body in the R mainstem bronchus will create an intrapulmonary shunt how?
Prevent ventilation to a lung that is perfused
- inhalational induction will be slower
List common LABAs
salmeterol, formoterol, arformoterol, indacaterol, vilanterol, olodaterol
all are beta-2 selective
*Initial therapy for COPD with LAMA. Combined LAMA-LABA therapy for patients with severe breathlessness
List common Long-acting muscarinic antagonists — The LAMAs (also known as long-acting anticholinergic medications)
tiotropium,
aclidinium,
umeclidinium,
glycopyrrolate
*Initial therapy for COPD with LAMA