Respiratory pathophysiology 4

Question 1

The Haldane effect describes how the

Answer 1

oxygen tension in the blood determines the blood’s ability to buffer CO2

Question 2

Inhibition of hypoxic pulmonary vasoconstriction increases

Answer 2

both shunt and dead space; increased dead space diminishes CO2 excretion and manifests as hypercapnia

Question 3

Identify the MOST appropriate strategy for mechanical ventilation in the patient with COPD.
a. I:E ratio 1:1
b. FiO2 <50%
c. Respiratory rate 7 breaths per minute
d. tidal volume 10-12 mL/kg

Answer 3

c. respiratory rate 7 breaths per minute
(a way to increase the expiratory time? per Apex)

Question 4

For patients with COPD, always consider _____ for procedures involving the extremities and the lower abdomen.

Answer 4

regional anesthesia

Question 5

For COPD patients, do not consider neuraxial anesthesia if the patient requires sensory blockade >

Answer 5

T6

Question 6

This block should be avoided in patients with COPD.

Answer 6

interscalene blockade b/c it causes paralysis of the ipsilateral hemidiaphragm

Question 7

For patients with COPD receiving regional anesthesia, be careful of

Answer 7

excessive sedation and ventilatory depression

Question 8

What gas should be avoided for patients with COPD?

Answer 8

nitrous oxide is associated with rupture of pulmonary blebs–> pneumothorax

Question 9

Volatile agents impair

Answer 9

hypoxic pulmonary vasoconstriction (>1.5 MAC) and increase shunt
unless shunt is severe, it can be overcome by increasing FiO2

Question 10

For patients with COPD, select a volatile agent with

Answer 10

a low blood:gas solubility

Question 11

All halogenated anesthetics are

Answer 11

bronchodilators (sevo and iso are better than des)

Question 12

Key considerations for mechanical ventilation of the COPD patient:

Answer 12

use a tidal volume of 6-8 mL/kg IBW
use a longer expiratory time
add PEEP (stay alert for dynamic hyperinflation)
slow inspiratory flow

Question 13

Atelectasis is exacerbated by

Answer 13

muscle relaxants and longer surgeries

Question 14

A patient with COPD is double stacking. Which interventions will improve this patient’s condition? (select 2)
a. increase inspiratory time
b. decrease respiratory rate
c. disconnect the circuit
d. increase inspiratory flow

Answer 14

b. decrease respiratory rate
c. disconnect the circuit

Question 15

Dynamic hyperinflation occurs when a

Answer 15

new breath is given before the patient was able to exhale the previous breath fully
this is also known as breath stacking

Question 16

Risk factors for dynamic hyperinflation include

Answer 16

high minute ventilation
increased airway resistance
reduced expiratory flow (such as COPD)

Question 17

Consequences of dynamic hyperinflation include

Answer 17

barotrauma
pneumothorax
hypotension

Question 18

Treatment of dynamic hyperinflation (auto-PEEP) includes

Answer 18

removing the patient from the breathing circuit to allow for the pressure in the lungs to equalize with the atmospheric pressure
prolong expiratory time (increasing I:E ration, reduce RR, reduce flow resistance by using a larger diameter ETT & frequent suctioning if needed)

Question 19

What can lead to increased airway resistance?

Answer 19

secretions
obstructed ETT
fighting the ventilator

Question 20

Factors that reduce expiratory flow include

Answer 20

bronchoconstriction
airway collapse
inflammation

Question 21

How can the cardiac system be impacted from auto peep?

Answer 21

impaired venous return
hypotension
overestimation of CVP & PAOP

Question 22

All of the following are examples of restrictive lung disease EXCEPT:
a. sarcoidosis
b. cystic fibrosis
c. negative pressure pulmonary edema
d. flail chest

Answer 22

b. cystic fibrosis

Question 23

Restrictive lung disease is an umbrella term for

Answer 23

a collection of disorders that impair normal lung expansion during inspiration

Question 24

Areas of restriction include the

Answer 24

pulmonary interstitium
pleura
rib cage
and/or abdomen

Question 25

Categories of restrictive ventilatory defects include:

Answer 25

acute intrinsic chronic intrinsic disease of the chest wall, mediastinum, & pleura other

Question 26

What are examples of acute intrinsic disorders that cause restrictive disease?

Answer 26

aspiration upper airway obstruction

Question 27

What are examples chronic intrinsic disorders that cause restrictive disease?

Answer 27

sarcoidosis amiodarone-induced pulmonary fibrosis

Question 28

Restrictive ventilatory diseases of the chest wall, mediastinum, and pleura include

Answer 28

flail chest pleural effusion ankylosing spondylitis

Question 29

Other examples of restrictive ventilatory defects include

Answer 29

pregnancy obesity ascites

Question 30

_________________ is diagnostic for restrictive lung disease

Answer 30

A FEV1 and FVC <70% - the FEV1/FVC ratio is unchanged

Question 31

One of the most significant risks of RLD is

Answer 31

barotrauma

Question 32

The best ventilatory strategies for RLD include

Answer 32

tidal volume= 6 mL/kg IBW RR= 14-18 breaths/min PIP <30 cmH2O I:E ratio= 1:1

Question 33

Characteristics of restrictive lung disease include

Answer 33

decreased lung volumes and capacities decreased compliance intact pulmonary flow rates

Question 34

Patients with RLD have reduced ______________ making them more prone to _________________

Answer 34

FRC; rapid arterial desaturation

Question 35

All of the following reduce the incidence of ventilator-associated pneumonia EXCEPT: a. oropharyngeal decontamination b. minimizing the duration of mechanical ventilation c. limiting sedation d. proton pump inhibitors

Answer 35

d. proton pump inhibitors

Question 36

Aspiration most commonly occurs during

Answer 36

anesthetic induction and intubation or within 5 minutes of extubation

Question 37

Aspiration can lead to

Answer 37

airway obstruction, bronchospasm, impaired gas exchange, and bacterial respiratory infection

Question 38

Risk factors for aspiration pneumonitis include

Answer 38

pregnancy trauma emergency surgery GI obstruction GERD PUD hiatal hernia ascites difficult airway management cricoid pressure impaired airway reflexes seizures residual neuromuscular blockade

Question 39

Mendelson's syndrome is a

Answer 39

chemical aspiration pneumonitis that was first described in OB patients receiving inhalation anesthesia

Question 40

Risk factors for Mendelson's syndrome include

Answer 40

Gastric pH <2.5 Gastric volume >25 mL (0.4 mL/kg)

Question 41

Pharmacologic prophylaxis to prevent aspiration includes

Answer 41

antacids H2 antagonists GI stimulants Proton pump inhibitors antiemetics

Question 42

Signs and symptoms of aspiration icnlude

Answer 42

hypoxemia (hallmark sign) dyspnea tachypnea cyanosis

Question 43

Primary treatment of aspiration includes

Answer 43

tilting the head downward (or to the side) suctioning the upper airway securing the airway (if indicated) applying PEEP

Question 44

Patients who aspirate must be observed

Answer 44

in the PACU

Question 45

A patient can be safely discharged to home if they do NOT experience any of the following within ________ of the aspiration event:

Answer 45

two hours new cough or wheeze, radiographic evidence of pulmonary injury A-a gradient >300 mmHg SpO2 decrease >10% of preoperative values on room air

Question 46

The best method to prevent ventilator associated pneumonia is to

Answer 46

avoid intubation all together minimize the duration of mechanical ventilation

Question 47

Aspiration causes three potential problems:

Answer 47

gastric contents enter the airway gastric contents cause a chemical burn to the airway & lung parenchyma infectious material enters the airway

Question 48

What is the result of gastric contents entering the airway?

Answer 48

risk of airway obstruction

Question 49

What is the result of gastric contents causing a chemical burn to the airway and lung parenchyma?

Answer 49

risk of bronchospasm and impaired gas exchange

Question 50

What is the result of infectious material entering the airway?

Answer 50

bacterial infection (not all aspiration leads to infection)

Question 51

Routine use of pharmacologic prophylaxis for patients NOT at risk for aspiration is

Answer 51

NOT recommended

Question 52

_____________ to reduce the risk of aspiration is NOT recommended

Answer 52

anticholinergics