Q: Despite passing weaning parameters, poor cough strength is a reliable indicator of failed extubation. What is an easy bedside method to test adequate cough strength in a patient who otherwise seems ready for extubation?
Answer: After detaching endotracheal tube (ETT) from the ventilator circuit, an index card is held about 2 cm from the end of the ETT. A patient who is unable to moisten the card with few efforts of cough is more likely to fail extubation. 1
Extubation failure is well documented in patients who cannot cough on demand despite good weaning parameters. More appropriate method to test the cough strength is to insert a spirometer into the ventilator circuit. Strength of cough can be measured with peak expiratory flow (PEF) during the cough. PEF ≤60 L/min are five times more likely to fail extubation.
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