The Effect of a Recruitment Maneuver on Respiratory Function Following Bronchoscopy

Abstract

Background:

Atelectasis and hypoxemia may occur in invasively ventilated patients undergoing bronchoscopy. This study aimed to assess the respiratory effects of recruitment maneuver (RM) in these patients and explore the population likely to benefit from RM after bronchoscopy.

Methods:

This single-center, prospective, observational study included subjects undergoing bronchoscopy who were invasively ventilated. RM was performed 5 min after bronchoscopy by maintaining breaths at a pressure control of 20 cm H₂O and a PEEP of 20 cm H₂O for 1 min. Lung aeration, monitored using electrical impedance tomography (EIT), was assessed throughout the study. High recruitability was defined as an increase in end-expiratory lung impedance (EELI) greater than 20% relative to its value before RM (△EELI/EELI), along with a decrease in the global inhomogeneity (GI) index due to RM.

Results:

Of the 80 subjects who completed the study, 32 met the predefined criteria for high recruitability. Subjects’ respiratory-system compliance (C_RS) before bronchoscopy (odds ratio [OR] 0.921 [0.854–0.993], P = .032) and the decrease in the ratio of P_aO2/F_IO2 due to bronchoscopy (OR 0.097 [0.020–0.457], P = .003) were significantly associated with high recruitability. In subjects with high recruitability, significant improvements were observed in C_RS in the dorsal region (15.3 ± 6.3 vs 13.5 ± 6.0, P = .002), center of ventilation (43.8 ± 4.8 vs 43.0 ± 4.8, P = .01), GI index (0.39 ± 0.07 vs 0.44 ± 0.08, P < .001), and P_{aO 2} /F_{IO 2} (257.1 ± 123.5 vs 212 ± 106.6, P < .001) due to RM after fiberoptic bronchoscopy, while no such benefits were observed in subjects exhibiting low recruitability.

Conclusions:

In subjects with lower C_RS before bronchoscopy and a decreased P_aO2/F_IO2 due to bronchoscopy, RM after bronchoscopy improved C_RS in the dorsal regions, promoted more uniform ventilation, and improved oxygenation. These patients are likely to benefit more from post-bronchoscopy RM.