Positive end-expiratory pressure

Positive End-Expiratory Pressure (PEEP)

Positive End-Expiratory Pressure (PEEP) is a critical concept in respiratory therapy and mechanical ventilation. It refers to the pressure maintained in the lungs (alveolar pressure) above the atmospheric pressure at the end of the exhalatory phase of respiration.

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A mechanical ventilator, commonly used for applying extrinsic PEEP.

Overview

PEEP helps to keep the alveoli open during the latter part of expiration, improving gas exchange and oxygenation. It is particularly significant in treating patients with acute respiratory distress syndrome (ARDS) and other forms of respiratory failure.

Types of PEEP

There are two primary types of PEEP:

1. Extrinsic PEEP: This form of PEEP is externally applied through a mechanical ventilator. It is often set based on a patient's specific respiratory needs.
2. Intrinsic PEEP: Also known as auto-PEEP, this occurs due to incomplete exhalation, leading to air trapping in the lungs.

Application in Mechanical Ventilation

In mechanical ventilation, PEEP is used to increase lung volume, improve oxygenation, and prevent atelectasis.

Pressure Support

Pressure support refers to the additional pressure provided during inspiration to assist the patient's breathing efforts. Unlike PEEP, which is a constant baseline pressure, pressure support varies with each breath.

Clinical Implications

PEEP can significantly impact lung mechanics and gas exchange. Its application must be carefully tailored to each patient to avoid potential complications such as barotrauma and reduced cardiac output.

See Also

• Mechanical Ventilation
• Respiratory Therapy
• Pulmonary Medicine

External Links

• National Institute of Health - PEEP and its Effects
• American Thoracic Society - PEEP in ARDS