Understanding Continuous Positive Airway Pressure (CPAP) and Continuous Negative Airway Pressure (CNP)

Learning the fundamentals of CPAP and CNP are important for CPT® coding purposes. By gaining a better comprehension of these services, healthcare coding and billing professionals can help ensure accurate coding while safeguarding full reimbursement. Let’s take a look at some of the details that define these services when it comes to respiratory therapy coding and billing. 

Continuous Positive Airway Pressure (CPAP)

What is CPAP and how is this service utilized?

Continuous positive airway pressure (CPAP) is classified as a non-invasive technique that provides single levels of air pressure from a flow generator. CPAP’s ultimate goal is to prevent the collapse of the oropharyngeal walls and the obstruction of airflow during sleep. This circumstance occurs in obstructive sleep apnea (OSA). Positive pressure may be applied by way of a nasal mask or by a mask applied over the nose and mouth or through a tube placed into the trachea to assist patients with a lung disorder.

The correct corresponding CPT code is:

• (94660) Continuous positive airway pressure ventilation (CPAP), initiation and management

• The related revenue codes are 0410 and 0419.

How is BiPAP different than CPAP?

Understand that BiPAP is a non-invasive method of ventilatory support. This method actually incorporates CPAP and pressure support ventilation. Note that BiPAP does not have a separate code in CPT, because it is a component of CPAP. Per American Medical Association’s (AMA) instruction, providers must report the CPAP code for BiPAP.

Know that it is not appropriate to bill for BiPAP using CPT codes 94002-94003 for invasive ventilation.

Understand that CPT code 94660 may be used for the initiation and subsequent management of CPAP or BiPAP.

Can services be billed per hour?

Services should be billed per day, not per hour, for CPAP and BiPAP. An entry in the NCCI Manual states that practitioner ventilation management (CPT codes 94002–94005, 94660, 94662) and critical care (CPT codes 99291, 99292, 99466–99486) include respiratory flow volume loop (94375) and breathing response to hypoxia (94450) testing if performed.

Note: High-flow oxygen treatments that produce a “CPAP-like” effect should not be billed with 94660. If measurable, bill as oxygen treatment with UB-04 revenue code 0271.

Continuous Negative Airway Pressure (CNP)

How is this service utilized?

The main use for negative-pressure ventilation 94662 is for nighttime respiratory muscle rest in patients. This is seen in, for example, patients with chronic obstructive pulmonary disease (COPD) or neuromuscular disorders. Patients experience an increase in quality of life because the alveolar ventilation can be augmented, and symptoms of chronic hypoventilation alleviated without tracheal intubation or tracheotomy. The patient is able to speak, drink, sleep and eat normally; complications associated with endotracheal, or tracheostomy tubes are avoided.

The correct corresponding CPT code is:

• 94662 Continuous negative pressure ventilation (CNP), initiation and management

• The related revenue codes are 0410 and 0419.

Understand that negative-pressure ventilation is usually not employed in the acute situation, but rather is used as a means of intermittent support for chronic lung failure.

Can services be billed per hour for this service?

Like CPAP and BiPAP, services are billed per day, not per hour, for CNP. The entry mentioned above in the NCCI Manual also applies here stating that practitioner ventilation management (CPT codes 94002–94005, 94660, 94662) and critical care (CPT codes 99291, 99292, 99466–99486) include respiratory flow volume loop (94375), and breathing response to hypoxia (94450) testing if performed.

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