The Impact of Mechanical Ventilation Modes on Complications of Fiberoptic Bronchoscopy in Critically Ill Patients.

Objective: The effects of fiberoptic bronchoscopy are not elucidated in different mechanical ventilation modes. The present study aimed to evaluate the effects of fiberoptic bronchoscopy on lung mechanics, ventilation parameters, and gas exchange in 2 often-used modes, volume control and pressure control, in invasively ventilated patients followed up in the intensive care unit.

Material And Methods: Eligible patients were screened and included in the study after intensive care unit-fiberoptic bronchoscopy database search. Patients who underwent fiberoptic bronchoscopy under volume control and pressure control mechanical ventilation modes were compared. The primary outcome was the occurrence of any complication within the first 24 hours after the procedure, and secondary outcomes were changes in lung mechanics (dynamic lung compliance and airway resistance) and gas exchange (arterial partial pressures of oxygen and carbon dioxide).

Results: A total of 61 patients (median age: 69 years, 60.7% male) were included. Twenty-nine (47.5%) patients were ventilated in volume control mode and 32 (52.5%) in pressure control mode during the fiberoptic bronchoscopy procedure, and the median (interquartile range) duration of the procedure was 9 [8-11] minutes. Baseline dynamic lung compliance, airway resistance, arterial partial pressures of oxygen and carbon dioxide, and the fraction of inspired O2 were similar in both groups. After fiberoptic bronchoscopy, dynamic lung compliance decreased in both groups, and airway resistance and peak airway pressures increased but reached pre-fiberoptic bronchoscopy values at the 1st hour after the procedure. No significant differences were detected in both groups in terms of blood gas values and lung mechanics in the 1st and 24th hours after the procedure. In both groups, the 24th hour fraction of inspired O2 was the same as the pre-fiberoptic bronchoscopy values, but the ratio of arterial partial pressure of oxygen and the fraction of inspired O2 improved. No complications developed in patients within 24 hours after the procedure.

Conclusion: No differences were detected in terms of gas exchange and pulmonary mechanics, and complications in volume control and pressure control modes in critically ill intubated patients.