Both people and pets can suffer from pulmonary edema (fluid in the lungs), a condition that usually discloses an underlying disease. However, this symptom alone can be scary and sometimes life-threatening. If you notice your dog coughing or becoming short of breath, immediately make an appointment with your vet to deduce if the condition is cardiogenic (originating in the heart) or noncardiogenic. Cardiogenic forms of pulmonary edema can be fatal, so the quicker you treat it, the better the prognosis.
What Is Pulmonary Edema?
Pulmonary edema refers to a condition where the alveoli (tiny clusters of air sacs in the lungs) fill with fluid instead, displacing the amount of possible air intake and making it hard to breathe. This condition usually comes on as a result of heart failure, cancer, a traumatic event like electrocution or shock, or a head injury. In most cases, pulmonary edema can be resolved with a diuretic medication like furosemide, but the underlying reason for the condition needs to be addressed.
Symptoms in Dogs
Several symptoms can signify a case of pulmonary edema in your dog. If your dog is panting excessively, it's necessary to watch it closely. Coughing along with unusually rapid breathing could signify that your dog is not receiving the proper amount of oxygen. Dogs with pulmonary edema may also present with a distended jugular vein. If left untreated, your dog's lips may become blue, a condition known as cyanosis. If this happens, an emergency trip to the vet is warranted.
Varieties and Causes
The most severe form of fluid in the lungs—cardiogenic pulmonary edema—results from an increase in pulmonary capillary pressure due to heart failure. Pets that suffer this condition usually have an underlying heart disease condition, one that most likely has contributed to prior health issues in the past. This type of edema is located only on the left side of the lungs and can be life-threatening, especially when complete heart failure is involved.
Noncardiogenic pulmonary edema, on the other hand, is usually dispersed throughout both sides of the lungs and can result from severe shock, a blockage of the airway from seizure or lodged foreign body, or from sepsis (bacteria in the bloodstream) during severe infection.
How to Treat Cardiogenic Pulmonary Edema
Upon arrival at your vet's office, a complete examination of your dog will be performed which will include listening to the heart through a stethoscope. In most cases, thoracic radiographs (X-rays) are used to diagnose all forms of pulmonary edema. If a cardiac issue is found, treatment will begin with supplemental oxygen, rest, and the administration of Lasix (furosemide), a common diuretic.
Furosemide is almost always used as an immediate line of treatment in cases of congestive heart failure to remove excess fluid buildup in the lungs and other areas of the body. However, your vet may prescribe something stronger, like spironolactone or hydrochlorothiazide (diuretics), or a vasodilator. In extreme cases, a mechanical respirator may be provided.
Follow-up treatment for cardiogenic patients consists of medication to strengthen the heart and adherence to a low-sodium diet. If your vet prescribes furosemide for your dog or sends you home with a diuretic, watch your pet for signs of dehydration due to an imbalance of electrolytes in the bloodstream. If your dog experiences lethargy, depression, GI tract disturbances, or a seizure, alert your veterinarian to report the adverse reaction which will then require additional treatment.
Treatment of Noncardiogenic Conditions
For noncardiogenic conditions, the vet will inspect your dog for burns around the mouth area resulting from electric shock from an extension cord. Your vet will also check the airway (possibly by radiograph) to see if any foreign objects are lodged inside it, preventing full respiration. Upon detection, your vet will attempt to remove blockages under sedation; some blockages may require surgery.
In most noncardiogenic edemas, medicines are also used, including diuretics to remove excess fluid, anti-inflammatories to reduce swelling, and colloidal fluids to increase vascular pressure in the case of blood loss. Your vet will decide the best course of action and prognosis is usually favorable.
For issues unrelated to the heart, the vet will provide follow-up instructions to treat the underlying condition. In all cases, repeated diagnostic tests will verify the fluid level in your dog's lungs to assure successful treatment.
Cardiogenic pulmonary edema is hard to prevent if an underlying heart problem is present. However, proper care for your dog's existing condition can safeguard against fluid-filled lungs and other complications.
To prevent noncardiogenic edema, remove access to all unprotected electrical cords, and get immediate veterinary treatment should your dog suffer a seizure, even if it seems minor.
This article is provided for informational purposes only. If your dog shows any signs of illness, please consult a veterinarian as quickly as possible.
Pulmonary Edema In Dogs. Veterinary Manual, 2020
Diagnosis of Cardiovascular Disease in Dogs. Veterinary Manual, 2020
Furosemide for Dogs and Cats. Wedgewoodpharmacy.com, 2020
Bouyssou, Sarah et al. Radiographic Appearance of Presumed Noncardiogenic Pulmonary Edema and Correlation With the Underlying Cause in Dogs and Cats. Veterinary Radiology & Ultrasound, vol 58, no. 3, 2016, pp. 259-265. Wiley, doi:10.1111/vru.12468