Use of Lung Ultrasound to Assess the Efficacy of an Alveolar Recruitment Maneuver in Rabbits With Acute Respiratory Distress Syndrome

Abstract

Objectives To investigate the application of lung ultrasound (US) in the evaluation and implementation of alveolar recruitment maneuvers in acute respiratory distress syndrome (ARDS). Methods Twelve rabbits with saline lavage–induced lung injury were randomly divided into 2 groups: one with alveolar recruitment guided by lung US and the other with alveolar recruitment guided by maximal oxygenation. Recruitment maneuvers were applied according to a stepwise incremental positive end‐expiratory pressure method in both groups. In the oxygenation group, a sum of the partial pressures of oxygen and carbon dioxide exceeding 400 mm Hg was used to define adequate recruitment. In the lung US group, a new protocol for reaeration in US‐guided lung recruitment was used to guide treatment. Evaluation by lung US, respiratory mechanical parameters, the Smith pathologic score (Crit Care Med 1997; 25:1888–1897), and wet‐to‐dry ratio were compared between the groups. Results Opening pressure was significantly higher in the lung US group (mean ± SD, 23.4 ± 3.4 cm H2O) than the oxygenation group (18.7 ± 2.1 cm H2O; P < .05). The reaeration score in the lung US group significantly increased during alveolar recruitment (6.5 ± 1.6 points at baseline versus 13.8 ± 3.0 points after completion; P < .05). Lung compliance, dead space shunts, the Smith pathologic score, and tissue wet‐to‐dry ratio, however, were not significantly different between the groups. Conclusions Lung US is an effective means of evaluating and guiding alveolar recruitment in ARDS. Compared with the maximal oxygenation–guided method, the protocol for reaeration in US‐guided lung recruitment achieved a higher opening pressure, resulted in greater improvements in lung aeration, and substantially reduced lung heterogeneity in ARDS.

Utility of bedside lung ultrasound for assessment of lung recruitment in a case of acute respiratory distress syndrome

“…The LUS has been used for similar indications previously also by various authors in different case reports and observational studies but with a heterogeneity in methodological approach as well as investigation used for comparison. [6710111213141516171819202122] Few studies have been described in Online supplementary material. ARDS is a condition characterized by diffuse alveolar as well as lung capillary damage, interstitial edema, and alveolar flooding leading to increased lung water.…”

“…[7] Thereafter, other studies also assessed recruitment maneuver under direct guidance with bedside LUS with successful outcome. [11121314] Few studies used alternative approach to assess recruitment by LUS. [1516] Stefanidis et al .…”

Point-of-Care Ultrasound—A New Option for Early Quantitative Assessment of Pulmonary Edema

“…Moreover, the lung histopathological abnormalities in rabbits with OA-induced pulmonary edema and human pulmonary edema patients are similar (Jambrik et al 2010). In addition, the lung structures of rabbits could be clearly visualized by in vivo and ex vivo lung ultrasound (Soldati et al 2014;Li et al 2015). Therefore, the present study aimed to further evaluate the value of POCUS in the assessment of the severity of pulmonary edema by analyzing the relationship between the severity of pulmonary edema and the features of BLA using a rabbit OA-induced pulmonary edema model.…”

Usefulness of ultrasound in the management of acute respiratory distress syndrome

“…In an experimental study, Li et al . [38] reported that ultrasound-guided recruitment maneuver strategy results in significant improvement of lung reaeration when compared to oxygenation-guided strategy.…”