The challenge now is to address the current slow acceptance of CPAP for BLS programs. (Photo/Rick McClure)

Years ago, I authored an article in the Wisconsin EMS Association Journal titled “CPAP for Everyone.” At that time, “everyone” meant “everyone with respiratory distress.”

Today, using continuous positive airway pressure (CPAP) in conditions from chronic obstructive pulmonary disease (COPD) to conjestive heart failure (CHF) has proven beneficial in decreasing the work of breathing and avoiding the need for intubation, the latter of which is the desired outcome—patients requiring intubation are seven times more likely to die from their condition and their hospital stay is an average two days longer. This extra time is often spent in the intensive care unit, which carries with it its own unique complications and high cost.

ALS programs, predominantly for paramedics, have almost uniformly across the nation adopted CPAP, and many would agree that prehospital CPAP is the standard of care. Now the challenge is to address the current slow acceptance of CPAP for BLS programs.

Arguing in Favor
The primary argument in favor of BLS CPAP is that this level of provider has no other treatment option available to them than to wait until the patient loses consciousness and requires manual ventilation. Although EMTs in some systems now have nebulized bronchodilators for the COPD/asthma patient, they have nothing to offer the pulmonary edema patient but “tincture of accelerator.”

Watching the patient suffering from respiratory distress die before your very eyes when there’s another option seems the ultimate violation of the EMT Code of Ethics. Even though some would say the BLS provider could simply assist the patient’s respirations with the BVM, this is easier said than performed. It takes a skilled clinician to coach and appropriately time this technique and it’s almost impossible to do with the patient breathing rapidly and shallow without causing more anxiety and fear. Plus, assisting ventilations doesn’t decrease the work of breathing by providing the positive airway pressure CPAP does without pushing air into the stomach.

Defending BLS CPAP
The most common argument I hear against BLS CPAP is that BLS providers don’t have the critical thinking skills to determine who is a CPAP candidate nor the necessary tools to adequately monitor the patient on CPAP.

As to the first argument: While BLS providers may not be proficient in diagnosing the cause of respiratory distress, neither are ALS providers—or even emergency physicians—during the initial assessment and treatment of these patients. Studies have shown that both ALS providers and physicians misdiagnose the condition half the time until X-rays, lab tests and old records are obtained. Despite this, patients started on CPAP benefit equally regardless the underlying cause.

Determining who is a CPAP candidate isn’t based on heart rate, blood pressure or even pulse oximetry reading, but instead on the assessment of the work of breathing. This assessment is a basic skill every BLS provider has. It’s a “doorway” assessment based on level of consciousness (able to follow commands), patient posture (upright or tripod), one-word speech, and use of accessory muscles. Any EMT with a couple of years on the street has likely seen these patients.

On the other hand, there is no data that applying CPAP to someone who doesn’t require it causes any harm. The service will simply be out the cost of the equipment. When I instituted CPAP on several rural Wisconsin BLS agencies in 2006, I found I had to actively encourage my coworkers to use it. Once they became comfortable with the device, however, they readily accepted it and began to use it on just about anyone with shortness of breath. Over time they developed a great confidence of when to use it. This cycle of initial hesitation, followed by overuse and then refinement in application, is common among all levels of providers with any new technique or treatment.

As to the second argument: BLS providers need only rely on the same assessment of work of breathing to assess the effect of CPAP. There are only three consequences to CPAP administration: either the patient remains unchanged, improves or worsens. In the first two cases, continuation of CPAP is indicated. The most sensitive indicator for respiratory failure is level of consciousness. For CPAP to be effective, the patient must be able to follow commands and breathe spontaneously. As they tire and respiratory distress progresses to respiratory failure, their level of consciousness diminishes.

Again, no single objective vital sign is predictive of respiratory failure. While ALS providers may use capnography to monitor these patients, there is no data that a particular end-tidal CO2 level is predictive of outcome.

For that reason, I recommend BLS and ALS providers initially avoid the use of the device’s head straps. Instead, providers who help the patient hold the mask to the patient’s face can more intimately monitor the patient’s consciousness and coach them to breathe deeply. Once the patient appears to be doing well, the straps can be affixed.

Following & Fighting State Law
The largest barrier to BLS CPAP adoption is addressing BLS protocols dictated by the state. Currently, more than three-quarters of American states allow CPAP at the BLS level. In those states that don’t currently allow it, the burden is on representatives of BLS agencies to prove its worth. This can be difficult as BLS often lacks clear representation.

I suggest BLS services start a petition that includes the signatures of medical directors and local hospital administrators. This petition should be formerly presented to the state’s EMS oversight agency and physician advisory council if it exists. Don’t expect an easy road. Find a local or national expert to present an argument based on scientific evidence, not anecdotal accounts.

Wisconsin was the first state to adopt CPAP for BLS providers. This decision came as a result of a pilot project that required BLS services to collect data on outcomes and complications. There’s no published data that says CPAP by BLS providers is as effective as that by ALS providers. This lack of evidence is due to the extremely difficult challenge of performing prehospital research—a task that’s complex at the ALS level and almost impossible for BLS. But the absence of “evidence” should not be construed to be the evidence of “absence” against BLS CPAP. Some things in medicine, such as this, are appropriately based on best practices.

The absence of a public outcry, avalanche of lawsuits or even published accounts of harm over so many states allowing BLS CPAP should be “evidence” enough that this life-saving therapy is worthwhile and should become commonplace, if not the standard of care, for all BLS services.

Editor’s note: A version of this article first appeared in JEMS in November 2013.


  • Bruge P, Jabre P, Dru M, et al. An observational study of noninvasive positive pressure ventilation in an out-of-hospital setting. Am J Emerg Med. 2008;26(2):165–169.
  • Hubble MW, Richards ME, Jarvis R, et al. Effectiveness of prehospital continuous positive airway pressure in the management of acute pulmonary edema. Prehosp Emerg Care. 2006;10(4):430–439.
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  • Williams TA, Finn J, Perkins JD, et. al. Prehospital continuous positive airway pressure for acute respiratory failure: a systematic review and meta-analysis. Prehosp Emerg Care. 2013;17(2):261–273.

Keith Wesley, MD, FACEP, FAEMS, is the medical director for HealthEast Medical Transportation in St. Paul, Minn., and United EMS in Wisconsin Rapids, Wis. He’s authored several EMS textbooks and numerous articles and papers on EMS and is a frequent speaker at state and national EMS conferences. He can be reached at

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