Acute Pulmonary Edema

Question 1

DDx - acute shortness of breath or acute respiratory distress

Answer 1

PE
Pulmonary edema
ARDS
Pneumonia
Pneumothorax
Bronchospasm
Airway obstruction (aspiration, foreign body, mass)
Diffuse alveolar hemorrhage
Acute interstitial pneumonia
COPD exacerbation
Influenza
Cardiogenic shock
MI
Arrhythmia
Sepsis

Question 2

MOA and DDx - non-cardiogenic pulmonary edema?

Answer 2

MOA: changes in capillary permeability due to pathologic insult (direct or indirect)

Drowning, fluid overload, aspiration, inhalation injury, neurogenic, acute kidney disease, allergic reaction, ARDS

Question 3

MOA and DDx - cardiogenic pulmonary edema?

Answer 3

MOA: increased capillary hydrostatic pressure 2/2 elevated pulmonary venous pressure

Anything elevating left atrial pressures (atrial outflow obstruction, LV systolic and diastolic dysfunction, LV fluid overload, LV outflow obstruction, dysrhythmia, cardiomyopathy, MI)

Question 4

Evaluation of acute shortness of breath?

Answer 4

Troponin, CBC, electrolytes, ABG, BNP, BCx, BAL Cx

EKG, CXR, TTE, ?bronchoscopy, pulmonary artery catheterization, CT PE or VQ or Dopplers

Question 5

Initial management for MI w/cardiogenic shock?

Answer 5

• Central venous and arterial access
• Narcotics for pain control
• Cardiology c/s
• ICU transfer
• Consider anti-arrhythmics or cardioversion
• Consider inotropes and diuretics
• Hold anti-hypertensives

Question 6

Initial management for pneumonia?

Answer 6

IVF, IV ABX, supplemental O2

Question 7

If pulsus paradoxus is present, what should be considered?

Answer 7

Cardiac tamponade
Severe asthma

(Large decrease in SV, systolic BP, and pulse wave amplitude w/inspiration)

Question 8

Define acute respiratory failure.

Answer 8

Inadequate oxygenation of blood or inadequate ventilation (elimination of O2) or both

Hypoxia: PaO2<60
Hypercapnia: pCO2>50

Question 9

What information is needed to determine the underlying mechanism of hypoxia?

Answer 9

PaCO2
A-a gradient
Response to supplemental O2

Question 10

List the causes of hypoxemia.

Answer 10

1. VQ mismatch
2. Shunt physiology
3. Low available inspired O2
4. Hypoventilation
5. Diffusion impairment

Question 11

What is V/Q mismatch?

Answer 11

Defect in either alveolar ventilation (e.g., pulmonary edema) or perfusion (e.g., PE)

Question 12

What is shunting?

Answer 12

Little or no ventilation in perfused areas due to collapsed or fluid-filled alveoli; venous blood is shunted into the arterial circulation without being oxygenated (one end of the spectrum in V/Q mismatch)

Question 13

How can the causes of hypoxemia be quickly distinguished?

Answer 13

Normal A-a gradient -> hypoventilation or low inspired PO2

Both PaCO2 and A-a gradient elevated in VQ mismatch and shunting

VQ - responsive to supplemental O2

Shunting - NOT responsive to supplemental O2

Question 14

Initial management for COPD exacerbation?

Answer 14

Aggressive bronchodilator therapy
Steroids
Supplemental O2
BiPAP
Intubation if not response

Question 15

Initial management for PE?

Answer 15

Therapy w/anticoagulation

If evidence of R heart failure w/hypotension - thrombolytics; avoid aggressive volume resuscitation

Question 16

Initial management of CHF exacerbation w/cardiogenic pulmonary edema?

Answer 16

Correct hypervolemia w/diuretics if BP normal
Look for cause of exacerbation
Review current CHF treatment
Review recent echo, repeat if appropriate