What is the formula for static compliance?

The formula for static compliance is determined by the relationship between the exhaled volume and the plateau pressure, accounting for positive end-expiratory pressure (PEEP). Static compliance is a measure of the lung's ability to expand in response to a given pressure change. To calculate static compliance, the exhaled volume (which is typically equivalent to the tidal volume in a ventilated patient) is divided by the plateau pressure minus PEEP.

This method effectively assesses the elasticity and distensibility of the lungs and chest wall by isolating the pressure required to achieve lung inflation, excluding the effects of dynamic factors like airway resistance. By including PEEP in the denominator, the calculation reflects the actual pressures that contribute to lung inflation, ensuring that the compliance measured is representative of the lung's static characteristics rather than dynamic conditions during active breathing.

Thus, the accurate representation of static compliance is encapsulated in the chosen answer, which incorporates both the appropriate volume measure and the corrected pressure with respect to PEEP.