Q: During weaning of Ventilator, how much is load of work due to endotracheal tube (ETT)?


Answer: About 10% 

There is a continuous debate about applying ETT compensation during weaning. Most ventilators are equipped to provide Automatic Tube Compensation (ATC), but physicians advocating against ATC argues that increased work load  by ETT is equivalent to upper airways obstruction immediately following extubation, so ATC is not required. But literature continue to see arguments from both side.


References: 

1. Strauss C, Louis B, Isabey D, Lemaire F, Harf A, Brochard L. Contribution of the endotracheal tube and the upper airway to breathing workload. Am J Respir Crit Cared Med 1998;157(1):23-30. 


2. Branson RD. Endotracheal tubes and imposed work of breathing: what should we do about it, if anything? Critical Care 2003;7(5):347–348. 

3. Figueroa-Casas JB, Montoya R, Arzabala A, Connery SM. Comparison between automatic tube compensation and continuous positive airway pressure during spontaneous breathing trials (SBTs). Respir Care 2010;55(5):549-554.