Clinicians from the Carl Gustav Carus University Hospital in Dresden, Germany, and the TU Dresden Faculty of Medicine have completed the world’s largest study on patient safety in major lung surgery. Results of the study, “Effects of Intraoperative Higher Versus Lower Positive End-Expiratory Pressure During One-Lung Ventilation for Thoracic Surgery on Postoperative Pulmonary Complications (PROTHOR): A Multicenter, International, Randomized, Controlled, Phase 3 Trial,” were published in the journal Lancet Respiratory Medicine.
The researchers said their goal was to better understand how different mechanical ventilation strategies used during lung surgeries impact postoperative complications. The phase 3 PROTHOR study followed 2,200 patients from 74 centers in 28 countries over an eight-year period, who were scheduled for lung surgery with one-lung ventilation to last more than one hour.
Patients were randomly assigned to one of two groups, both of which were evaluated for positive-end expiratory pressure (PEEP):
- High PEEP (10 cm H20) with regular recruitment maneuvers to help reopen closed alveoli
- Low PEEP (5 cm H20) without regular recruitment maneuvers
The primary endpoint was the occurrence of postoperative pulmonary complications (PPCs) within the first five days after surgery.
Remarkably, the incidence of postoperative complications did not significantly differ between the two groups (high PEEP: 53.6%; low PEEP: 56.4%). The study showed that ventilation with higher PEEP and maneuvers resulted in better gas exchange. Conversely, the low PEEP group experienced more episodes of hypoxemia (low oxygen levels) that required intervention (9% vs. 3%).
The researchers also found that low PEEP was linked to more stable circulatory conditions during surgery. The amount of intraoperative complications was significantly more frequent among the high PEEP group (49.8%) compared to the low PEEP group (31.3%), with hypotension being the most common complication.
Based on the mixed results, the authors determined that ventilation strategies should be made on an individual basis with shared decision-making between patients and clinicians.
“Especially in such complex procedures, anesthesia and differentiated ventilation play a crucial role in the success of the treatment,” said Alexander Kern, MD, a thoracic surgery specialist at Dresden University Hospital. “The PROTHOR study also shows us surgeons that optimal ventilation strategy must be selected individually to enhance patient safety.”
