General Pulmonology

Pulmonary Edema

Jen Seabright, PharmD
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Publish Date

Edema, the accumulation of excess fluid in body tissues, usually occurs in response to chronic illness, trauma, or medication use.1 Several types of edema exist, including lymphedema, peripheral edema, and pulmonary edema.1,2 Pulmonary edema occurs when extravascular fluid collects in the lung parenchyma.3 Hospitalization for acute pulmonary edema is associated with a 1-year mortality rate of up to 40%.4 Pulmonary edema may be classified as cardiogenic or noncardiogenic.3 

Cardiogenic pulmonary edema may be caused by3:

Noncardiogenic pulmonary edema includes acute lung injury with hypoxemia. It is caused by factors unrelated to the heart, including3:

  • Inhalation and injection of toxins (eg, illicit drugs)
  • Occupational exposure to toxic chemicals (eg, industrial solvents)
  • Aspiration of gastric contents
  • Pneumonia
  • Trauma, including strangulation
  • Sepsis
  • Blood transfusions
  • Burns
  • Pancreatitis

Presentation and Diagnosis

Patients with cardiogenic pulmonary edema may present with3:

  • Jugular venous distention
  • Peripheral edema
  • Increased blood pressure 
  • S3 gallop or murmurs
  • Patients with noncardiogenic pulmonary edema may present with3:
  • Signs of an active infection
  • Trauma
  • Burn injuries

Diagnostic Workup

Laboratory tests to consider when evaluating a patient with pulmonary edema include3:

  • Brain natriuretic peptide (BNP) testing; left ventricular myocytes secrete BNP when there is increased blood volume in the ventricle 
  • Arterial blood gas test, which may show respiratory alkalosis due to hyperventilation
  • Troponin test; troponin levels are typically increased when there is myocyte damage
  • Basic metabolic panel to check kidney function and electrolyte levels 
  • Urinalysis to screen for toxins, if relevant based on history
  • Complete blood count to check for anemia, which may cause pulmonary edema

Patients with cardiogenic pulmonary edema will have a BNP level greater than 1200 pg/mL, increased levels of troponin, and possibly increased creatinine levels.3 Chest radiograph may show increased heart size, pleural effusions, and short parallel lines at the periphery of the lungs (Kerley B lines).3 Transesophageal echocardiogram (TEE) findings may include decreased left ventricular function, severe valvular disease, problems with diastolic filling, and pericardial effusion with tamponade.3

In contrast, patients with noncardiogenic pulmonary edema will have an increased white blood cell count and BNP level less than 200 pg/mL.3 Chest radiographic will typically show diffuse infiltrates, a normal-sized heart, and minimal pleural effusions.3 Findings on TEE findings may include normal function of the left ventricle and valves with and no volume overload.3 

Differential Diagnosis of Pulmonary Edema

Other conditions to consider in the differential diagnosis of pulmonary edema include3:

  • Pulmonary embolism
  • Pulmonary fibrosis
  • Acute worsening of asthma or chronic obstructive pulmonary disease (COPD)
  • Sarcoidosis
  • Liver disease, which can be confirmed with liver function tests
  • Lymphangitic carcinomatosis (spread of cancer through the lymph system)
  • Other types of pulmonary edema, such as high-altitude pulmonary edema (HAPE)

Management of Pulmonary Edema 

The treatment goals in pulmonary edema are to correct the underlying cause and lessen the symptoms of fluid accumulation.4 Treatment for pulmonary edema should include4:

  • Relieving symptoms
  • Improving oxygenation
  • Maintaining cardiac output
  • Perfusion of vital organs
  • Reducing excess extracellular fluid

Loop diuretics — such as furosemide, torsemide, bumetanide, and ethacrynic acid — are the treatment of choice to decrease fluid overload.3 The following dosages of furosemide are recommended for patients with pulmonary edema4:

  • 4 mg/min intravenously (IV), given as a slow bolus; may repeat after 20 minutes, if needed
  • 40 to 80 mg by mouth (for patients with normal renal function)
  • 160 to 200 mg by mouth (for patients with renal insufficiency or heart failure)
  • Continuous IV infusion at 5-10 mg/h

Intravenous nitroglycerin may be added to lessen pulmonary congestion. It may be used if the patient has chest pain and a systolic blood pressure greater than 90 mm Hg.4 Dosing of nitroglycerin for pulmonary edema is as follows4:

  • Nitroglycerin spray at 400 µg every 5 minutes, up to a maximum dose of 1200 µg
  • Nitroglycerin sublingual tablet at 300 to 600 µg every 5 minutes, up to a maximum dose of 1800 µg
  • IV nitroglycerin (first-line treatment in acute pulmonary edema) at 5 to 10 µg/min; may double every 5 minutes, up to a maximum dose of 200 µg/min

Patients with low systolic blood pressure and lack of perfusion to the tissues may require treatment with dobutamine or dopamine. Dosages for these agents in the setting of pulmonary edema are as follows3:

  • Dobutamine at 2.5 to 20 µg/kg/min
  • Dopamine at 0.5 to 20 µg/kg/min, depending on desired effect; a low dosage increases blood flow, an intermediate dosage increases heart contractions, and a high dosage increases blood pressure

Ventilation is a nonpharmacologic intervention that aims to increase oxygenation, move fluids back into the capillaries, and reverse respiratory acidosis.4 It is typically reserved for patients with oxygen saturation (SpO2) less than 92%.4 Ventilation may be invasive (eg, endotracheal tube, tracheostomy) or noninvasive (eg, face mask or nasal plugs).4 

Intensive care is required for patients with pulmonary edema who3:

  • Require intubation;
  • Have symptoms of hypoperfusion;
  • Have an SpO2 less than 90% while on oxygen;
  • Have a heart rate less than 40 bpm or greater than 130 bpm; and/or
  • Have a systolic blood pressure <90 mm Hg.

Read more: Asystole

Monitoring Side Effects, Adverse Events, and Drug-Drug Interactions 

Hospitalized patients with pulmonary edema should have their weight, serum electrolytes, and renal function monitored daily.4 Individual medications and side effects to monitor include:

  • Nitrates, which can cause hypotension, reflex tachycardia, paradoxical bradycardia, and tachyphylaxis4
  • Loop diuretics, which can cause dizziness, gastrointestinal upset, electrolyte abnormalities, and dehydration5
  • Dobutamine and dopamine, which can cause tachyarrhythmias, ischemia, and hypotension4

The potential for drug interactions should be considered if new medications are started in the inpatient setting to treat the underlying cause of pulmonary edema. Importantly, nitrates should not be administered to patients who have received treatment with a phosphodiesterase inhibitor, such as sildenafil, within the previous 24 hours.4 

References

1. Malkinski N, Feldscher SB. Edema management. In: Skirven TM, Osterman AL, Fedorczyk JM, Amadio PC, Feldscher SB, Shin EK, eds. Rehabilitation of the Hand and Upper Extremity, 7th ed. Elsevier; 2021;57:798-811.

2. Midgely R, Pisano K. Therapist’s management of the stiff hand. In: Skirven TM, Osterman AL, Fedorczyk JM, Amadio PC, Feldscher SB, Shin EK, eds. Rehabilitation of the Hand and Upper Extremity. 7th ed. Elsevier; 2021;28:372-393.

3. Yesodharan G. Pulmonary edema. In: Beach SR, Christian CW, DaSilva MF, et al, eds. Ferri’s Clinical Advisor 2023. Elsevier; 2023;1288-1291.e1.

4. Purvey M, Allen G. Managing acute pulmonary oedema. Aust Prescr. 2017;40(2):59-63. doi:10.18773/austprescr.2017.013

5. Lasix [package insert]. Parsippany, NJ: Validus Pharmaceuticals LLC; 2018.  

Author Bio

Jen Seabright, PharmD, is a freelance medical writer in Pittsburgh, Pennsylvania.