A male patient in a hospital bed wears a ventilator whilst he is treated for coronavirus (Covid-19).

Treating Covid-19 patients using continuous positive airway pressure (CPAP) outside of a critical care unit

HSIB legacy content

HSIB legacy content

This investigation was carried out by the Healthcare Safety Investigation Branch (HSIB). Find out more about HSIB legacy.


This investigation looked into the safety risk of treating patients with coronavirus (COVID-19) with Continuous Positive Airway Pressure Ventilation (CPAP) outside of critical care units.

A significant proportion of people attending hospital with COVID-19 need help with their breathing. Often this takes the form of oxygen therapy which is given through a face mask or through little tubes that sit in the nose. Despite oxygen therapy, some patients still struggle to take in enough oxygen to breathe on their own and become exhausted. This is known as respiratory failure. These patients’ breathing may be assisted with the use of a special device, which delivers a flow of oxygen-enriched air at a constant pressure, and is connected to a mask, or hood, worn by the patient. This is known as CPAP.

There was an increase in numbers of people requiring hospital admission because of respiratory failure and requiring breathing support using CPAP during the peaks of the COVID-19 pandemic. CPAP is an aerosol-generating procedure (AGP) because it can result in the release of airborne particles (aerosols) from the respiratory tract. When someone is suspected or known to be suffering from an infectious agent like coronavirus these infectious particles pose a risk of infection to others. Therefore, this required the creation of safe environments and efficient patient pathways to reduce the risk of infection when using this form of respiratory support.

Reference event

The investigation was launched after HSIB became aware of a patient with COVID-19 requiring CPA, who was found on the floor of a side room having called for assistance. The CPAP tubing had become disconnected from the mask meaning the patient’s breathing was not supported. Sadly, the patient died.

Investigation summary

This investigation sought to:

  • Understand the contextual factors surrounding the care of people with coronavirus requiring CPAP in hospital.
  • Describe the systemic factors influencing the risks associated with using this form of non-invasive respiratory support during the pandemic.
  • Identify whether recent national guidance addressed identified safety issues.
Investigation report