Surgery for obstructive sleep apnea often involves surgery of the throat that removes, repositions, and/or tightens tissue. Although the goal is to improve or eliminate the sleep apnea, the risks include the potential to disrupt normal function, especially speech and swallowing. Fortunately, speech changes have always been rare, but changes in swallowing have always been considered a greater risk.
Soft palate surgery is the most common type of sleep apnea surgery, although surgery on other structures in the throat (in what I call the Tongue Region) may be needed. To understand why trouble swallowing may occur after surgery, it is important the the soft palate plays an important role in swallowing, with two key functions:
- Sealing up the area behind the soft palate so that liquids and food do not travel from the back of the mouth to the back of the nose (called nasal regurgitation); and
- Contributing to guiding liquids and food down the throat and towards the stomach instead of remaining in the throat or entering the lungs.
Trouble swallowing after sleep apnea surgery has not been studied thoroughly, with the available studies having some important limitations. First is that not every study has examined trouble swallowing. The second is that these studies did not follow study participants over time to see if trouble swallowing (or other risks) would resolve and also did not always characterize the severity of the trouble swallowing. Nevertheless, more research should exist. As Lee Carlson, one of my high school teachers said in our yearbook when asked about the best excuse he ever heard: “There are reasons, but there are no excuses.”
The largest review of the literature on complications after sleep apnea surgery included 45 studies, many of them on procedures that are no longer performed widely (like laser-assisted uvulopalatopharyngoplasty). There were studies that examined trouble swallowing after surgery, but they characterized it in various ways that made results difficult to evaluate. As mentioned above, different studies measured side effects at different points in time and in different ways, but the review indicated that approximately 30% of study participants had some trouble with swallowing. It was not possible to evaluate at what point in time this occurred or whether it was likely to improve or resolve over time.
New research shows that trouble swallowing generally resolves in 3-6 months
Jason Chau, MD from the University of Calgary has led a team that has examined swallowing changes after different types of sleep apnea surgery. In the January 2023 issue of The Laryngoscope, they showed that sleep apnea surgery was associated with substantial worsening in swallowing at 1 month after surgery, with resolution of these changes at 3 and 6 months. They followed 100 study participants in whom he performed sleep apnea surgery, checking on their swallowing function before and after surgery with a validated questionnaire that measures swallowing function: the Eating Assessment Tool (EAT-10).
My personal experience is that there are a few patients that have changes in swallowing after sleep apnea surgery, but fortunately it is unusual to have substantial changes that persist long-term that affect normal eating and drinking. I always follow patients until their swallowing returns to normal, and if it does not, I refer patients for speech and swallowing therapy with trained speech language pathologists. Again, fortunately this is unusual (less than 1% of my patients) but still important that patients know it is possible (so I mention this in the list of surgical risks on my website).