Hi doctor , my uncle is operated for aspergillus in lungs ,there was a fungus ball which was attached between lungs and chest . operation was successful but its nearly 20 days of him being on ventilator ,his age is 54 .past 4 days they have done tracheostomy .and he has recovered well .but he can breathe without ventilator for 2 to 4 hours a day .please recommend how many days will it take to come completely out ventilator .