Dr. Myers, will I need to use my CPAP machine for obstructive sleep apnea after bariatric surgery?

The short answer is; most likely you will be able to discontinue your CPAP machine sometime after you lose a significant amount of weight from bariatric surgery. In fact over 80% of the time patients with a diagnosis of obstructive sleep apnea will resolve this obesity related medical problem after bariatric surgery.

Let me explain. As our weight increases we see our size become larger. What we do not see is the soft tissue of obesity increasing in our throat making our airway crowded. When we are sitting up and awake gravity brings our tongue down and the muscles of our neck and throat keep our airway open. However, when we lay down on our backs gravity works against us and our tongue falls back into the back of our throat further narrowing the airway that is compromised by the soft tissue of obesity. In addition, when we fall asleep our muscles relax and the airway may become nearly or completely closed. That is why many persons of size are loud snorers! As the air is moving in and out the soft tissue in the airway vibrates making the snoring sound. This may not wake the person snoring but it certainly can keep the one they are sleeping with from sleeping!

But obstructive sleep apnea is not just about sleep. It is mostly about what happens to your heart while you are sleeping. When you are sitting up and awake your red blood cells are likely to be about 98% saturated with oxygen. You need that oxygen for your body' tissues to stay healthy. Your heart especially needs the oxygen to keep beating as well as possible. When a person with obstructive sleep apnea falls asleep and and their airway becomes obstructed their oxygen level decreases since they are not moving air in and out as well as they should. their oxygen level may fall into the 80% range, down to the 70% range into into the 60's and even lower. Our hearts do not like and sometimes your heart will run off a string of irregular beats and the heart will no longer be pumping and the person will be found dead in bed in the morning. Even if your heart does not react in this manner, it will be trying to keep up with the needs by pumping faster and harder. However, since it is starving for oxygen it is often in relative heart failure during the night. That is why people that have obstructive sleep apnea often have to get up at night to urinate since there heart is strained and gives off a hormone that tells the kidneys that you are "drowning" from heart failure and you need to get rid of some of the body's fluid. In addition people of size that have obstructive sleep apnea often wake up in the morning with their ankles still swollen because of the heart failure during the night.

This all can be prevented by using a CPAP machine, (continuous positive airway pressure), that pushes air under gentle pressure into the airway keeping the soft tissue out of the way and keeping the airway open, This allows them to breath normallykeeping their oxygen where it should be.

Since it takes about 3 weeks for the heart to recover from its previous failure we require all of our patients that have obstructive sleep apnea to be using their CPAP machine for at least 3 weeks before their bariatric operation and expect them to continue using it after their operation until they lose enough weight that the machine is no longer needed. This generally takes from 3 to 6 months to lose the amount of weight necessary.

In the hospital our patients may be on pain medicine that could make their sleep apnea temporarily worse so they are continuously monitored for their oxygen level and this information is sent to the central nursing desk for additional monitoring.

At Fresh Start Bariatrics at Riverside we are constantly looking for ways to make bariatric surgery safer for our patients and this includes making sure they are doing everything possible to be as healthy as possible before and after their operation.

Of course there are other reasons people have obstructive sleep apnea and that is why about 15% to 20% of people need to be on CPAP despite loosing their weight. For example, I have a BMI of about 27 but I use CAPAP because I have a palate deformity that narrows my airway.

Fortunately, over 80% of our patients with obesity related obstructive sleep apnea will have resolution of this problem.

Does anyone have any further questions about this? Feel free to post a coment or ask a questiion




by clicking on the word "comment" at the end of this posting.