Hyperinflation Respiratory Therapies in Cardiac Surgery Patients: A Randomized, Observer-Blinded, Prospective Clinical Trial

Postoperative pain due to surgical incision may limit lung expansion. After cardiac surgery, all patients receive respiratory therapies, because it is critical to expand lung after surgery to prevent respiratory complications such as lung collapse (atelectasis) due to shallow breathing or accumulation of airway secretions.

Although incentive spirometer is the most common method used for lung recovery after cardiac surgery, some studies were not able to find any benefits from the use of incentive spirometer. Inspiratory positive-pressure breathing (IPPB), Intermittent positive end expiratory pressure (EzPAP), and chest airway clearance (Metaneb) are hyperinflation therapies used after surgery. The purpose of this research study is to determine which hyperinflation respiratory therapy provide better lung recovery after cardiac surgery.

Hyperinflation Respiratory Therapies:Participants will be randomly assigned one of the hyperinflation respiratory therapy, intermittent positive pressure breathing (IPPB) and the EzPAP or the Metaneb.

1. Intermittent positive pressure breathing (IPPB) is a respiratory therapy technique which will support your breathing by providing pressure support. This respiratory method will increase air volume breathing in.
2. The EzPAP is another respiratory treatment and participants will breath against to resistance in order to prolong the time the lung remain open.
3. The Metaneb will provide resistance when patients breathing in order to prolong the lung opening.

Hyperinflation therapy will be performed every 4 hours in the intensive care unit (ICU). Each respiratory therapy session will take about 15 minutes. Participants' pulmonary function will be evaluated daily to monitor the lung recovery with microspirometer which will take place approximately 5 minutes. Total study duration is about 96 hours after surgery or until discharge from the Intensive Care Unit.