Postoperative Chest Drainage Strategy Remains Inconclusive

Suction may not prevent prolonged air leaks better than the water seal method following lung surgery, according to a new study.

Researchers at the Istituto Nazionale dei Tumori (Milan, Italy) reported interim results of the AirINTrial, a study which randomized patients to suction at 15 cm H2O negative pressure for the first 3 postoperative days, or to negative pressure the first day followed by water seal to day 3 (after which drains were removed or connected to a Heimlich device), followed by discharge on day 5. The interim report detailed the results of the first 500 of a planned 1,600 patients, all adult candidates for lung resection (except pneumonectomy), with stratification by type of resection.

The result showed that 26 patients overall were discharged with a drain at postoperative day 7, while 33 remained hospitalized with a drain due to persistent air leak. Persistent air leaks on day 7 after surgery occurred in a similar proportion of patients with both interventions, 10% with suction versus 14% with water seal, respectively. The researchers found a borderline advantage to suction in anatomical resection, with 10% having an air leak at day 7 versus 17% with water seal.

A subgroup analysis in the suction group suggested that prolonged air leak was more common the higher the air flow on postoperative day two, rising from 0% among those with low flow under 200 mL/min to 27% among those in the top quartile at more than 800 mL/min; the highest rate (60%) was in those with high pressure and negative maximal intrapleural pressure on day two. The rate was 40% in the intermediate-flow patients who failed to reach negative pressures, and instead had maximal intrapleural pressure near zero. The study was presented at the Society of Thoracic Surgeons (STS) annual meeting, held during January 2013 in Los Angeles (CA, USA).

“The results suggest that there is a certain level of negative intrapleural pressure that favors air leak stop,” concluded lead author Francesco Leo, MD, PhD, and colleagues. “Data on air flow and pressures may be helpful in defining the risk of prolonged air leak, but its usefulness needs further confirmation.”

Water sealed drains consist of three chambers: a water seal, suction control, and a drainage collection chamber. They are designed to allow air, blood, or fluid to be removed from the pleural cavity, while at the same time preventing backflow of air or fluid into the pleural space. This allows expansion of the lungs and restoration of negative pressure in the thoracic cavity. Appropriate chest drain management is required to maintain respiratory function and hemodynamic stability.

Related Links:
Istituto Nazionale dei Tumori