Pulmonary edema: Signs and Treatment Guidelines
Pulmonary edema is the accumulation of excessive fluid in the alveolar walls and alveolar spaces of the lungs. It is an acute medical emergency that occurs due to an increase in pulmonary capillary venous pressure leading to an accumulation of fluid in the alveoli usually due to acute left ventricular failure.
Edema is excessive fluid accumulation in the interstitial spaces, beneath the skin or within the body cavities.
There exist different types of edema such as peripheral edema, cerebral edema, pulmonary edema, macular edema, and lymphedema.
Causes of pulmonary edema
All the factors which contribute to increased pressure on the left side and pooling of blood on the left side of the heart can cause cardiogenic pulmonary edema.
The result of all these conditions will be increased pressure on the left side of the heart: increased pulmonary venous pressure--> increased capillary pressure in lungs--> pulmonary edema.
Coronary artery disease with left ventricular failure (myocardial infarction)
Valvular heart diseases on the left side of the heart (stenosis and regurgitation)
Signs and symptoms
The patient will present with
- Frothy blood-tinged sputum,
- Respiratory distress,
- Rhonchi and crepitations on auscultation.
- Elevated jugular venous pressure.
Chest x-ray reveals loss of distinct vascular margins, Kerley B lines and diffuse haziness of lung fields.
Management of pulmonary edema
Management must be immediate:
ABC protocol must be assessed very fast in these patients
The patient should be positioned in a propped up position in bed.
Obtain an intravenous line.
Give 100% oxygen at a rate of 3.5–5 Liters per minute.
Ventilatory support may also be required.
Start intravenous frusemide 40 milligrams initially and a repeat with a higher dose every 20–30 minutes up to 200mg maximum total dose.
If the patient is not already on digoxin, you may need to digitalize except where the edema resulted due to myocardial infarction, heart failure, and, acute myocardial infarction.
Treatment of the underlying cause is key.
Non Invasive Management
Non-Invasive Management can be achieved by
pre-Load Reduction using; Nitroglycerin, Sodium nitroprusside, Isosorbide dinitrate, Loop diuretics, Morphine, and nesiritide require extreme care, BIPAP.
After-Load Reduction using ACE inhibitors or angiotensin receptor-neprilysin inhibitor: captopril, enalapril, lisinopril, perindopril, Angiotensin receptor blockers, Sodium nitroprusside
Invasive treatment involves the use of the following modalities;
- Intra-aortic balloon pump)
- Valve replacement (in case of valvular issues)
- Percutaneous Coronary Intervention)
- Ventricular assist devices
- Extracorporeal Membrane Oxygenation
- Cardiac transplant
- Coronary Artery Bypass Graft