Trouble breathing or shortness of breath after coronary bypass surgery?

There are actually several causes for breathing difficulties following coronary bypass surgery (aka CABG).

“Shortness of breath is very common after coronary artery bypass grafting,” says Dr. Michael Fiocco, Chief of Open Heart Surgery at Union Memorial Hospital in Baltimore, Maryland, one of the nation’s top 50 heart hospitals.

“Primary causes include atelectasis (collapse of small air sacks in the lungs), and fluid within or around the lung.”

My mother, following her quintuple bypass surgery, had this exact problem.

The term “pulmonary effusion” came up when she was examined, and the fluid and partial collapse was detected with imaging tests.

She had bouts of “labored breathing” or “difficulty breathing,” that in part, could be explained by the atelectasis and effusion.

Dr. Fiocco continues, “Every patient has these issues after surgery to some degree. Atelectasis occurs due to poor inspiratory effort due to the pain of the incision.

“This improves with walking, deep breathing exercises and coughing.”

My mother was instructed to use a little gadget called an incentive spirometer.


It’s not only given to coronary bypass patients, but anybody who needs bed rest following any kind of surgery … to encourage lung expansion, which will help prevent breathing difficulties and pneumonia.

The patient places the mouth on the spirometer’s mouthpiece and slowly inhales, while watching the device record a numerical value of how much air is being inhaled.

Coughing gets the lungs working; very important for coronary bypass patients to help with their breathing and prevent any problems.

A respiratory therapist will also visit the CABG patient, but despite these measures, the coronary bypass patient may still (and commonly) experience some trouble with breathing.

So what can be done, then, about the fluid buildup in the lungs after coronary bypass surgery?

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Dr. Fiocco explains, “Fluid is removed with diuretics (fluid pill). They increase your urine output and draws fluid off the lungs.”

But what if the patient, following coronary bypass surgery, has renal failure?

My mother had “mild” renal failure, and hence, there was a period where she could not receive diuretics, because their effect (promoting urinary output) would stress the kidneys!

Solution? She was on fluid restriction until her creatinine level (measure of kidney function) was acceptable.

Over time the fluid buildup in her lungs disappeared, and her lungs eventually appeared normal on imaging.

A coronary bypass patient, however, can end up with so much fluid that it really makes breathing difficult, and frequently.

Dr. Fiocco says, “Occasionally, so much fluid accumulates around the lung that it must be drained with a catheter.”

My mother’s surgeon actually mentioned this as a plan if a follow-up CAT scan were to show that the fluid was still present.

“Rarely, fluid collections around the heart can cause shortness of breath requiring drainage,” adds Dr. Fiocco.

“Even more rare is a pulmonary embolus, or blood clot to the lung which is treated with blood thinners.”

Finally, a possible cause of trouble breathing after coronary bypass surgery, especially when the previous mentioned issues have been ruled out, is plain anxiety.

My mother’s cardiologist reported to me that there were a few instances in which she complained of labored breathing, and visibly had trouble with normal breathing,

But once the doctor had her engaged in conversation unrelated to her CABG, her breathing appeared perfectly normal. He told me this was anxiety related.

dr. fiocco

Dr. Fiocco specializes in treating artery disease, valvular disease and aortic aneurysm. His heart care expertise has earned him recognition by Baltimore Magazine as a Top Doctor in 2010, 2011, 2013, 2016 and 2017.
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.  



Top image: Shutterstock/Africa Studio

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