Cuff leak test

Cuff Leak Test

Evaluate the patient's breathing capacity with the Cuff Leak Volume Test by following these steps:

1. Suction endotracheal and oral secretions, then switch the ventilator to assist control mode, ensuring the patient receives volume-cycled ventilation.

2. With the cuff inflated, document the displayed inspiratory and expiratory tidal volumes to determine if they are comparable.

VT inspiration (inflated)

VT expiration (inflated)

3. Release the cuff.

4. Measure the expiratory tidal volume over the next six breathing cycles, as will stabilize at a plateau after a few cycles.

VT expiration (cuff deflated 1 )

VT expiration (cuff deflated 4)

VT expiration (cuff deflated 2 )

VT expiration (cuff deflated 5)

VT expiration (cuff deflated 3 )

VT expiration (cuff deflated 6)

Three lowest value average

5. Calculate the average of the three lowest values.

6. The cuff leak volume is determined by the difference between the inspiratory tidal volume (taken prior to cuff deflation) and the averaged expiratory tidal volume (measured after cuff deflation).

Cuff leak test (> 110 ml cut-off value)

A difference of more than 110 mL in expiratory tidal volumes before and after cuff deflation has a negative predictive value (NPV) of 98% for post-extubation stridor, as demonstrated in the original study by Miller and Cole, effectively ruling it out.

A cuff leak volume test of ≤ 110 suggests a tendency for unsuccessful weaning from mechanical ventilation, indicating that extubation may be possible within 12 hours after administering systemic steroid, which would facilitate successful extubation.

Risk factors for laryngeal edema

Woman
Intubation > 6 days
large endotracheal tube
reintubated after unplanned extubation
traumatic intubation