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Explaining the expiratory time constant

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Author: Clinical Expert Group, Hamilton Medical

Date of first publication: 04.03.2019

The expiratory time constant (RCexp) provides valuable information about the patient's lung mechanics.
Explaining the expiratory time constant

RCexp is the product of compliance and resistance, and indicates how long the patient takes to exhale. In this short video, Dr. Ian Rechner from the The Royal Berkshire Hospital (UK) uses syringes and balloons to demonstrate the principle.

You can also follow the link below to read our bedside tip on using and interpreting the expiratory time constant to assess the lung condition and optimize ventilator settings.

Photo Dr. Rechner holding two balloons
Photo Dr. Rechner holding two balloons

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