OSA (Obstructive Sleep Apnea) – IT IS AS BAD AS IT SOUNDS!
I recently consulted on a case where OSA was center stage in a motor vehicle accident. Although the defendant had multiple significant medical issues, the lack of proper CPAP use (including lack of documentation of proper use), and little documentation of appropriate medical management of their OSA led to a finding of causation in the accident – in essence, the driver was not using their CPAP and fell asleep at the wheel and caused a major accident. This led me to bring up several thoughts about OSA which I will share. Over the years I have encountered many patients with OSA who simply stop using their CPAP or fail to use it consistently or fail to make sure that it is at the correct setting by not doing appropriate follow up testing. This is not good! Nightly use of effective CPAP is necessary unless there is some other appropriate OSA intervention. These other interventions might be a large weight loss or use of a mouth prosthetic or throat surgery (UPP uvulopalatoplasty surgery) for OSA.
30 years ago, when OSA was relatively unknown, our methods and tools were quite basic. We would find folks who would say “doc, I was driving down the road and next thing I knew I woke up after hitting a tree”. That would start the OSA workup – and there were very few Sleep Labs at that time.
Our screening questions were also quite basic and went like this: 1. Do you fall asleep when you don’t want to or expect to? 2. Do you fall asleep when you watch TV? 3. Do you nod off at stop lights? 4. Are you tired all day? 5. Do you wake up with a full day’s energy or do you wake up just as tired as when you went to bed?
Another set of questions went like this: 1. Do you make loud “snoring” noises at night? Actually, the “snoring” is NOT the nice sonorous “sawing wood” or ”zzzzzzz’s” – it is choking and sputtering and gagging noises. 2. Have others banished you to a distant sleeping location (couch or basement) because of the noises you make when you sleep? 3. Have others complained about the noises you make at night when you are sleeping? Often the spouse would be questioned. Responses are often: “I have to wear ear plugs at night to be able to sleep because he snores so badly” or “I don’t get any sleep because he stops breathing and I have to poke him in the ribs or roll him over to get him to start breathing again.”
Times have changed! With the internet, anyone can go online and find an OSA screening questionnaire that they can take. They can record their own sleep with a smart watch or smart phone and identify episodes of OSA. Some of the preliminary tests for OSA can be done at home to help make a diagnosis. However, the “Sleep Study” – (polysomnography) – is the gold standard. Frequently, patients will have a “split” sleep study – the first half of the night, they are monitored for OSA and if there is overwhelming evidence of OSA, then the second half of the night is used to titrate CPAP to eliminate the OSA.
30 years ago, CPAP machines were essentially the back end of a vacuum cleaner with some pressure regulation. They were loud and bulky. Patients often put them in a closet or adjacent room and drilled holes in the wall for the hoses. Masks were limited to one or two designs and were quite stiff. Patients always complained about them but said “I use the mask and CPAP because I feel so much better in the morning – I feel normal when I use it!”. Today’s CPAP machines are small and quiet. Some are portable and battery operated. There is a large variety of masks – full face, mouth, nasal pillows and combinations. Patients are encouraged to keep working with the respiratory therapist until they get the mask that fits and works the best. The air delivered to the CPAP mask can be heated or cooled and can be humidified or dehumidified. Some CPAP devices can Auto Titrate the pressure of air delivered to eliminate sleep apnea. Almost all CPAP devices have technology to monitor sleep, use. apnea episodes and CPAP effectiveness. Many can transmit this information to the medical provider. This feature is most important especially for commercial drivers. Additionally, some insurance companies will not pay for the monthly rental of a CPAP machine if the patient is not transmitting information about nightly use and effectiveness.
OSA BEHIND THE SCENES- THIS IS THE BAD PART:
What is OSA? OSA happens when the upper airway gets blocked – usually by the tongue relaxing and flopping backwards and closing the airway when sleeping- blocking inhalation – essentially causing a choking episode. Sometimes the upper airway itself is very compliant and under the negative pressure used to take in a breath, the upper airway collapses and closes. Either of these mechanisms can lead to a choking event – the upper airway blocks and the chest may be working to pull in another breath but the blocked airway does not allow this. (This causes the choking and grunting sounds of OSA patients.) The choking leads to loss of oxygen in the blood (desaturation) and to the release of adrenaline – as it would be when one is being choked by any method. The adrenalin release is part of the “fight or flight” response to danger. The problem is that adrenaline raises the Blood Pressure and heart rate and this constant release of adrenaline causes premature ASCVD (arteriosclerotic cardiovascular disease) with its attendant consequences of High Blood Pressure, Heart Attacks and Strokes. The bottom line is that folks with uncontrolled OSA beat up their cardiovascular system every night – and increase their risk for early onset Cardiovascular diseases. Eventually, a cough or exhalation leads to pushing the air up out of the lungs and pushing the obstruction out of the way. This is followed by rapid breathing to make up for the oxygen deficiency. This rapid breathing may occur in the setting of a partial airway obstruction leading to the loud and irregular sputtering and gagging noises characteristic of OSA. The patient often does not wake up with these events and are unaware of the events.
Many patients with OSA really don’t think much of it and say “Doc, I am sleeping – I don’t care. I just am tired all the time.” There are 5 stages of sleep. Most people are aware of being awake or asleep. However, the goal of sleep is to get about 2 hours of REM (Rapid eye movement -typically Stage 4 sleep) sleep each night – THIS IS WHEN WE RECHARGE OUR BATTERY for the next day! We get bursts of REM sleep – 20 minutes here, 30 minutes there and 15 minutes, etc. These episodes add up. The problem is that as a person goes into deep sleep and REM sleep, the muscles relax more and more. This can allow the tongue to flop back into the throat and obstruct the airway or allow the upper airway itself to narrow. So, as a person gets closer to the needed deep sleep and REM sleep, they tend to have more OSA episodes. They do not necessarily wake up but they bounce between Stage 1 and Stage 3 sleep – getting very little of the necessary REM sleep that they need. The bottom line is that the patient with significant OSA becomes VERY SLEEP DEPRIVED – because they do not get enough REM sleep – not enough to “recharge their battery every night”. This leads to overwhelming tiredness during the daytime and nodding off or falling asleep during the daytime when one does not want to or expect to. This can happen while sitting quietly or even while driving a car or truck or running equipment.
What is CPAP? Continuous Positive Airway Pressure ( CPAP ) is the most common method we use to prevent the upper airway blockage. CPAP pressure is measured in centimeters of water. This is a constant flow of air from the CPAP machine sent through the mask into the airway to maintain a specified pressure to keep the tongue from flopping back into the airway and to keep the upper airway from collapsing. Today’s CPAP machines have lots of technology to measure use and effectiveness and some will change settings automatically so that OSA episodes are eliminated. Some machines relay this information to your Pulmonary medical provider through Apps, the internet or by means of a smart card which you can take to your provider.
OSA BOTTOM LINE:
CPAP utilization and effectiveness and regular visits with your OSA physician manager are essential to maintain good health and may be the key to continuing to maintain your Medical Certification and CDL.
Use of CPAP and documentation of CPAP effectiveness by electronic transmission or by means of a memory card to your OSA physician manager provide the proof that you are working to effectively manage your OSA and maintain safe driving.
Information on Obstructive Sleep Apnea and Commercial Driving:
The following is a link to a report from the University of Pennsylvania and sponsored by the Federal Motor Carrier Safety Administration (FMCSA) and the American Transportation Research Institute of the American Trucking Associations found that almost one-third (28 percent) of commercial truck drivers have mild to severe sleep apnea. https://www.fmcsa.dot.gov/sites/fmcsa.dot.gov/files/docs/Driving-Sleep-Apnea_508CLN.pdf
Another good resource is Trucker Docs: https://dotphysicaldoctor.com/commercial-drivers-manage-sleep-apnea-maintain-cdl/
Trucker Docs has lots of good information about OSA and CDL license and the role of the driver and the carrier for treatment and safe driving.