Acute Respiratory Failure Lecture Powerpoint

Question 1

Normal A-a gradient value range, higher A-a gradient means what?

Answer 1

10-20, higher means elevated pressure in alveoli than capillaries

Question 2

Vital capacity + residual volume =

Answer 2

total lung volume

Question 3

Causes of acute respiratory failure (5)

Answer 3

• decreased FiO2
• Ventilation without perfusion (deadspace ventilation)
• Diffusion abnormality (V/Q ratio affected)
• Perfusion without ventilation (shunting)
• Hypoventilation

Question 4

Decreased FiO2 causes (2)

Answer 4

• High altitude

- toxic gases

Question 5

Hypoventilation causes (3)

Answer 5

• COPD
• Neurological disease
• Obstructive sleep apnea

Question 6

Diffusion abnormality causes (4)

Answer 6

• Interstitial lung diseases
• pneumonia
• ARDS
• Pulmonary edema

Question 7

More dead space corresponds to ___ work of breathing

Answer 7

Increased

Question 8

Shunt definition

Answer 8

Blood flow that passes next to alveoli that are collapsed or filled with fluid and inflammation

Question 9

Physiologic deadspace =

Answer 9

Anatomic dead space + alveolar dead space

Question 10

Hypercapnia value

Answer 10

Elevated PaCO2 >45mmHg

Question 11

What causes hypercapnia? (2)

Answer 11

• Decrease in tidal volume

- decrease in respiratory rate

Question 12

Causes of increased dead space (4)

Answer 12

• COPD/emphysema
• asthma
• cystic fibrosis
• pulmonary fibrosis

Question 13

Signs and symptoms of hypercapnia are dependent on 2 variables

Answer 13

• level of CO2 in arterial blood

- rate of accumulation

Question 14

Mild to severe acute hypercapnia signs and symptoms

Answer 14

-anxiety to asterixis (wrist flapping) and delirium

Question 15

Normal individuals do not exhibit depressed consciousness until PaCO2 >….

Answer 15

75-80mmHg, if chronic will be 90-100

Question 16

Oxygen associated hypercapnic respiratory failure

Answer 16

Occurs in COPD patients who are used to higher CO2 levels and thus if placed on supplemental O2 will not receive input to breath and worsen with it as a result

Question 17

If you suspect oxygen associated hypercapnic respiratory failure and O2 at least 95%, ___ supplemental O2

Answer 17

Decrease to 90-93%

Question 18

Venturi masks provide ___O2 compared to nasal prongs

Answer 18

More

Question 19

Good candidate for noninvasive positive pressure ventilation has these 5 characteristics

Answer 19

• pH <7.3
• Moderate to severe respiratory distress
• RR >25
• Increased work of breathing
• Must be able to spontaneously breath

Question 20

CMV ventilation

Answer 20

Set respiratory rate and volume is automated with no patient work, requiring heavy sedation

Question 21

Assist control

Answer 21

Set minimum respiratory rate and volume, patient may initiate breath but will always be given a set volume (sometimes uncomfortable for patients)

Question 22

IMV ventilation

Answer 22

Set minimum respiratory rate and volume, spontaneous breaths are volume that patient is able to independently able to achieve

Question 23

Pressure controlled ventilation

Answer 23

Set inspiratory pressure level, respiratory rate, and PEEP, insiration ends after pressure achieved

Question 24

Pressure support

Answer 24

Set PS and PEEP, helps patients wean off as they control spontaneous breathing

Question 25

PEEP

Answer 25

5 is physiologic PEEP, mainstay of adequate oxygenation by preventing collapse of alveoli upon exhalation

Question 26

PEEP too high consequence

Answer 26

-Blood vessel compression

Question 27

Noncardiogenic pulmonary edema

Answer 27

Caused by increased capillary permeability most often caused by ARDs and less often HAPE, neurogenic pulmonary edema, opiod overdose, etc.

Question 28

Acute respiratory disress syndrome

Answer 28

Complication of multiple other diseases resulting systemic response with acute onset of bilateral alveolar infiltrates and hypoxemia, has excess fluid in the interstitium and alveoli and alveoli collapse resulting in dire consequences

Question 29

Consequences of ARDS (3)

Answer 29

• Decreased lung compliance*** Hallmark sign
• Impaired gas exchange
• pulmonary hypertension

Question 30

ARDS almost always presents with…

Answer 30

….acute inciting event

Question 31

Things not seen on an X ray in ARDS

Answer 31

• no caridomegaly
• no pleural effusion
• no kerley B lines

Question 32

ARDS must have these symptoms to make clinical diagnosis (3)

Answer 32

• respiratory symptoms beginning within 1 week of clinical insult
• unexplained opacities present on cxr or CT
• Moderate to severe impairment of oxygenation even on ventilation

Question 33

ARDS treatment

Answer 33

Treat underlying condition and supply supportive care for respiratory failure

Question 34

ARDS prognosis

Answer 34

Depends on funciton of # of organ systems (more important than severity of respiratory failure) and age of patient, generally those who die do so within 2 weeks and if survive need prolonged course of recovery and supportive care