Pulmonary

Question 1

Pathophys of ARDS

Answer 1

Injury causes capillary leak, protein leaves vascular space leading to interstitial and alveolar flooding. This all causes gas exchange abnormalities, decreased lung compliance and elevated PVR/pulm HTN

Question 2

Berlin definition of ARDS

Answer 2

1) less than 1 week of clinical insult
2) bilateral infiltrates not explained by effusion, atelectasis or nodules
3) edema not fully cardiac in etiology
4) PEEP greater than 5
5) P/F <300

Question 3

Prone positioning

Answer 3

Improves survival in severe ARDS P/F<150. Prone for 16 hours after trying to stabilize for 12-24 hours

Question 4

Steroids in ARDS

Answer 4

Improves survival in early mod-severe ARDS

Avoid in flu and late ARDS (week 2-3 of ARDS)

Question 5

Obesity and intubation

Answer 5

Decreased FRC leads to early desaturation after induction

Question 6

MACOCHA Score

Answer 6

Analyzes difficult airways

Question 7

Induction Agents

Answer 7

Propofol: best but causes hypotension. Onset 9-50 sec, lasts for 3-10 min. Dose 0.5-2 mg/kg
Etomidate: reduced adrenal steroidogenesis. Onset 30-60 sec, lasts for 3-5 min. Dose 0.15-0.3 mg/kg
Ketamine: reduced pressor response. Onset 60-120sec, lasts for 5-15 min. Dose 2 mg/kg

Question 8

Neuromuscular Blockade (RSI)

Answer 8

Succinylcholine: onset 30-60 sec, lasts 5-15 min. Dose 1-1.5 mg/kg.
Contraindications: hx of malignant hyperthermia, hyperkalemia, UMN and LMN lesions, myopathy, crush injury, severe burns, prolonged immobility

Rocuronium: onset 45-60 sec, lasts for 45-70 min. Dose 0.8-1.2 mg/kg
Sugammadex is reversal agent. 16 mg/kg

Question 9

Planning intubation success

Answer 9

Upper lip bite test: asses jaw movement
MACOCHA
preoxygenate
Videolaryngoscopy

Question 10

Tracheostomy indications

Answer 10

Difficult airway, prolonged MV: allows for oral hygiene, resp secretion clearance, early mobilization, conditioning

Facilitates vent liberation: decreases artificial airway resistance and anatomical dead space

Question 11

Percutaneous trach

Answer 11

Advantages: bedside, rapid and less $$, lower EBL and infection

Disadvantages: tracheal lac, esophageal perf

Contraindications: unstable c-spine, ambiguous surface anatomy, difficult airway

Question 12

Trach complications

Answer 12

Dislodgement: <7 days: fiber optic replacement with orotracheal intubation to stabilize. If >7d then reinsert

Obstruction: removed inner cannula

Tracheitis/stomal infection
Tracheomalacia

Question 13

Trach bleeding

Answer 13

Early: >7d. Surgical site bleeding
Late: granulation tissue, stomal infection, erosion of thyroid vessels, tracheal wall erosion or tracheoinnominate fistula

Question 14

Tracheal cuff pressure

Answer 14

Keep <15 mm Hg to prevent ischemic injury

Question 15

Bromchoscopy indications in ICU

Answer 15

Airway management
VAP
Hemoptysis
Symptomatic atelectasis/central obstruction
Aspirated foreign body

Question 16

Massive Hemoptysis

Answer 16

Mortality 13-17.8%
Due to TB, mycetoma, bronchiectasis, cancer and iatrogenic

Question 17

Bronchial Artery Embolization

Answer 17

Immediate success in 70-90%
Recurrence up to 58% in 30d

Surgery is effective in localized disease but otherwise high mortality in emergency setting (50%)

Question 18

Management of tracheal obstruction

Answer 18

Tracheostomy or resection for local dz
Emergent rigid bronch to reesrablish airway —> balloon dilate and stent

Fiberoptic flex bronch risks bleeding and airway compromise

Question 19

Negative pressure pulmonary edema

Answer 19

Young, developed larygospasm during anesthesia that results in edema and resp failure. Large pressure swings against a closed epiglottis

Question 20

Post extubation stridor risk factors

Answer 20

Traumatic intubation
Intubation >6d
Large ETT
Female gender
Reintubation after unplanned extubation

Question 21

Physiology of obstructive resp failure

Answer 21

Increased airway resistance: inflammation, edema, smooth muscle tone, mucous

Increased WOB: increased CO2 (fever) and subsequent minute ventilation. Hyperinflation that increases dead space ventilation, inspiratoey threshold load and WOB

Question 22

Inspiratory threshold load

Answer 22

Must overcome intrinsic PEEP (autopeep) to inhale

Negative pressure required to initiate flow = inspirstory threshold load

For normal person: alveolar pressure needs to be slightly less than 0 to initiate flow. In hyperinflation, alveolar pressure may be high (18) and so alveolar pressure must decrease by >18 to initiate flow

Question 23

Inhaled beta adrenergic agonists

Answer 23

Albuterol, levalalbuterol

Short acting and quick onset
Given via nebular or MDI (no benefit to nebulized)
No benefit to increasing dose or continuous

Question 24

Inhaled anticholingergics (ipratropium)

Answer 24

Short acting

COPD: evidence for efficacy is conflicting
Asthma: increased bronchodilation compared to b agonists alone

Question 25

Corticosteroids

Answer 25

Decreases symptoms, rate of tx failure and LOS, early initiation can minimize delay of effect Route: no benefit to IV over oral Dosing: equivalent of 40-60 mg prednisone Duration: will vary depending on trajectory, taper not always needed

Question 26

Antibiotics

Answer 26

Asthma: no empiric abx, context driven COPD: abx recommended with severe exacerbation requiring hospitalization

Question 27

Magnesium

Answer 27

Recommended for asthma: 2g single dose with life threatening exacerbation or failed response to other therapy Not recommended for COPD

Question 28

PEEP for inspiratoey threshold load

Answer 28

Can raise extrinsic PEEP (ventilator) to partially match intrinsic peep to help patient initiate flow more easily

Question 29

Non-invasive ventilation data

Answer 29

Asthma: no compelling evidence of benefit COPD: decreases RR, increased TV and MV, decreased LOS, decreased intubation rate and treatment failure rate, decreased mortality

Question 30

Heliox

Answer 30

Lower density than air, increasing laminar flow Better for large airways disease than asthma (tracheal stenosis or obstruction) No RCTs demonstrating benefit