A PEEP Valve, or Positive end-expiratory pressure valve is a device used for Continuous Positive Airway Pressure(CPAP), Biphasic Positive Airway Pressure (also called Bilevel Positive Airway Pressure) or an intubated patient. On an intubated patient the PEEP valve can be a part of a Bag valve mask assembly or may be attached to the patient circuit on a mechanical ventilator.
A PEEP valve administers positive end expiratory pressure to the airway. In essence, constantly maintaining a pressure on the lower airways at the end of the breathing cycle. This prevents the alveoli from collapsing during expiration.
PEEP can be constant such as in the case of CPAP administration, or can taper, such as during BiPAP administration or when a patient is being mechanically ventilated. PEEP is measured centimeters of water (cmH2O.) Ranges of PEEP are 5-10 cmH2O for CPAP and 10-40 cmH2O for mechanically ventilated patients. PEEP for CPAP and Vented patients are generally controlled by a sping pressure one way valve. Increasing PEEP is done by changing the PEEP valve, or can be adjusted by a knob on some patient circuits.
BiPAP PEEP is mechanically controlled. During BiPAP assisted exhalations, the BiPAP machine reduces the PEEP pressure to ease work of exhalation. At the end of the exhalation cycle, the PEEP is increased by the BiPAP machine to prevent Alveolar collapse.