Assessment of the Effect of Recruitment Maneuver on Lung Aeration Through Imaging Analysis in Invasively Ventilated Patients: A Systematic Review

Abstract

Background: Recruitment maneuvers (RMs) have heterogeneous effects on lung aeration and have adverse side effects. We aimed to identify morphological, anatomical, and functional imaging characteristics that might be used to predict the RMs on lung aeration in invasively ventilated patients.Methods: We performed a systemic review. Studies included invasively ventilated patients who received an RM and in whom re-aeration was examined with chest computed tomography (CT), electrical impedance tomography (EIT), and lung ultrasound (LUS) were included.Results: Twenty studies were identified. Different types of RMs were applied. The amount of re-aerated lung tissue after an RM was highly variable between patients in all studies, irrespective of the used imaging technique and the type of patients (ARDS or non-ARDS). Imaging findings suggesting a non-focal morphology (i.e., radiologic findings consistent with attenuations with diffuse or patchy loss of aeration) were associated with higher likelihood of recruitment and lower chance of overdistention than a focal morphology (i.e., radiological findings suggestive of lobar or segmental loss of aeration). This was independent of the used imaging technique but only observed in patients with ARDS. In patients without ARDS, the results were inconclusive.Conclusions: ARDS patients with imaging findings suggestive of non-focal morphology show most re-aeration of previously consolidated lung tissue after RMs. The role of imaging techniques in predicting the effect of RMs on re-aeration in patients without ARDS remains uncertain.

Lung Recruitment Maneuvers Assessment by Bedside Lung Ultrasound in Pediatric Acute Respiratory Distress Syndrome

“…The observation of A-lines in previously collapsed regions could be a potential marker of lung overdistension if maneuvers are not stopped at that point. The benefit of RMs needs to be balanced between reaeration and overdistention [ 25 ].…”

Electrical Impedance Tomography in Acute Respiratory Distress Syndrome Management

“…The distinction between PEEP responders and nonresponders is important to avoid PEEP-induced lung strain. Classically, responders are patients who improve oxygenation, compliance, driving pressure, or dorsal aeration after an RM or stepwise increments in PEEP (28, 39). Using EIT, Wolf et al (40) observed that, after applying a stepwise RM, improvements in dorsal collapse preceded physiologic recruitment (Pa co 2 + Pa o 2 > 400 mm Hg).…”

Advanced respiratory monitoring in mechanically ventilated patients with coronavirus disease 2019-associated acute respiratory distress syndrome

“…Diagnosing, monitoring and resolving atelectasis while preventing overdistention is one of the main challenges in the mechanical ventilation. Computed tomography (CT) is the golden standard for the assessment of aeration and potential for recruitment in ARDS [ 16 , 17 ], but lacks the practicality of bedside monitoring. Especially when resources are constrained due to an epidemic, bedside monitoring might serve as a viable or even essential alternative.…”