Dysphagia following cardiac surgery: Risk factors and paths forward

After a major health procedure like cardiac surgery, a patient’s main focus should be one thing: recovery.

However, new research published in the Journal of Thoracic and Cardiovascular Surgery highlighted previously underrecognized threats to postoperative success: Dysphagia, or swallowing impairment, characterized airway invasion of ingested material into the lungs (aspiration).

TAVR Surgery in OR
Thomas Beaver, M.D., chief of the division of cardiovascular surgery, preps for a surgery with his team.

This recent study conducted at UF Health is the first prospective clinical trial to directly image swallowing function in a large group of recovering cardiac patients and was led by Emily Plowman, Ph.D., an associate professor in the department of speech, language and hearing sciences and Eric Jeng, M.D., an assistant professor in the UF College of Medicine’s division of cardiovascular surgery.

Results revealed high rates of dysphagia that were significantly higher than previous reports not utilizing direct imaging assessment techniques. Importantly, presence of postoperative dysphagia was associated with a 43% longer hospital stay, ~$50,000 increased cost of care, pneumonia, reintubation, and death. The study also revealed five independent risk factors for dysphagia development that included: larger endotracheal tube size, longer intubation duration, reoperative procedures, a higher number of transesophageal echocardiogram images, and higher New York Heart Association heart failure scores.

“The prevalence of unsafe swallowing during the acute recovery period in this group of cardiac surgical patients was astounding,” Plowman said. “Two-thirds penetrated liquids into the upper airway during swallowing, while 29% demonstrated tracheal aspiration of ingested materials.”

The report noted that only 6% of recovering cardiac surgical patients had safe swallowing.

“Of great clinical importance were the observed high rates of silent aspiration,” Plowman recalled.

Typically, when something ‘goes down the wrong pipe’, an immediate and audible defensive cough response is triggered to remove foreign material from the airway. Therefore, coughing acts as an immediate auditory heuristic cue that clinicians will observe during a clinical bedside exam to signal that a patient’s airway has been breached with entry of food, liquid or saliva into the lungs.

But sometimes—it’s quiet.

“Clinical bedside exams do not directly visualize bolus flow during swallowing and are known to be inaccurate at detecting silent aspiration,” Plowman said.

University of Florida researchers examine the "invisible" and extremely challenging condition of swallowing disorders, which often afflict patients with throat cancer as well as those with neurodegenerative disorders or trauma to the neck. It significantly affects day-to-day life, making it a challenge to eat and avoid coming down with aspiration pneumonia.
Emily Plowman, Ph.D., examines a patient to determine what may be affecting his ability to swallow. (2017)

“Of the 53 instrumentally confirmed aspirating patients in our study, 20 passed the traditional bedside water swallow screening tool used in many cardiac ICU’s, missing over one-third of aspirating individuals,” she added.

Now, however, that protocol might be changing.

“These data have fueled some important new initiatives aimed at improving patient outcomes in this setting,” Plowman said. “Risk factor data are informing the development of a novel risk stratification tool, intended to inform personalized triaged care pathways of high risk individuals. Additionally, we are working hard to increase the clinical utilization of instrumental swallowing examinations.”

Plowman’s motto is a well-known adage: Knowledge is power.

But her collaboration with the UF Health’s cardiovascular surgeons to implement the knowledge has elevated the saying from words to real-life, tangible changes in patient outcomes.

“This project has really opened our eyes to what we have suspected for years; and now we can take steps to help the thousands of patients that undergo heart and aortic procedures each year,” said Thomas Beaver, M.D., chief of the division of cardiovascular surgery in the UF Department of Surgery.

“Our overarching 4-pronged model for optimal clinical care is to predict, prevent, detect and treat dysphagia and is being reviewed in an R01 grant at the National Institutes of Health. We hope to continue these efforts and validate a dysphagia prediction model that will be incorporated in an accessible electronic app to inform clinicians od relative dysphagia risk and guide postoperative care pathways,” Plowman said.

“In addition to implementation of direct imaging in high-risk patients, we are also working to develop and validate a sensitive bedside screening tool for standardized implementation in lower risk patients,” she said.

But they’re not stopping there.

Thanks to some generous pilot funding from physicians Tomas Martin, M.D., and George Arnaoutakis, M.D., directors of the UF Health Aortic Disease Center, the research team will examine the potential benefit of a targeted preoperative exercise program aimed at increasing a patient’s physiologic capacity to defend the airway in identified high risk patients awaiting surgery.

“In today’s world, it’s more than the just the surgeon, it’s now about the whole team — the surgeon, anesthesiologist, critical care, nursing, speech language pathologist, respiratory therapist, nutritionist, physical and occupational therapists, as no one part can succeed without the others,” Jeng said.

Gilbert R. Upchurch, Jr., M.D., the chair of the UF Department of Surgery, believes these are landmark findings that will inform and change postoperative outcomes for millions of patients.

“This impactful work will clearly benefit patients locally, but also can benefit all patients undergoing cardiac surgery nationally and internationally,” Upchurch said.