Gravity-driven modified whole-lung lavage improves procedural efficiency in pulmonary alveolar proteinosis.

BACKGROUND

Whole-lung lavage (WLL) remains the gold standard for symptomatic pulmonary alveolar proteinosis (PAP). However, conventional protocols are resource-intensive, relying on manual chest percussion, frequent position changes, and active negative-pressure suctioning to accelerate effluent drainage. We evaluated a modified gravity-driven workflow designed to improve procedural efficiency by optimizing hydrodynamics and minimizing manual airway manipulation.

METHODS

In this single-center retrospective cohort study, we analyzed 112 WLL procedures performed in 88 patients between October 1, 2007, and April 30, 2024. Procedures were categorized into a classic workflow (n=60; utilizing manual percussion, postural changes, and active negative-pressure suction) or a modified gravity-driven workflow (n=52). The modified technique employed a saline reservoir elevated to 100 cm, fixed supine positioning, and passive gravity drainage through a three-way stopcock to maintain a closed circuit. Primary outcomes included lavage duration, anesthesia duration, and fluid recovery rate. Generalized estimating equations (GEE) were used to adjust for baseline confounders.

RESULTS

Baseline characteristics were balanced between groups. The modified technique demonstrated superior efficiency. Compared with the classic technique, the modified workflow significantly reduced the median lavage duration [135 (interquartile range (IQR), 116-160) vs. 240 min (IQR, 211-360 min); P<0.001] and total anesthesia duration (240 vs. 390 min; P<0.001). The fluid recovery rate was significantly higher in the modified group (95.0% vs. 92.0%; P<0.001). Both techniques showed improvement in oxygenation at discharge, and no statistically significant between-group differences were observed in oxygenation outcomes in this cohort. No statistically significant between-group differences were observed in recorded complications, including pneumothorax, pleural effusion, and hemodynamic instability.

CONCLUSIONS

The gravity-driven modified WLL is an efficient technique. By utilizing increased hydrostatic pressure, this approach significantly reduces procedural time and improves fluid recovery. In this cohort, it was not associated with a detectable difference in short-term oxygenation outcomes or recorded complications.