Q: In last few years cough strength has been advocated as one of the weaning parameter. How cough strength can be objectively measured?


Answer: After inserting a spirometer into the ventilator circuit, and then patient instructed to cough, the peak expiratory flow (PEF) is measured. If PEF less than 60 L/min, chances of extubation failure is high. 



References:

1. Smina M, Salam A, Khamiees M, et al. Cough peak flows and extubation outcomes. Chest 2003; 124:262.

2. Salam A, Tilluckdharry L, Amoateng-Adjepong Y, Manthous CA. Neurologic status, cough, secretions and extubation outcomes. Intensive Care Med 2004; 30:1334.