Pleural effusion during weaning from mechanical ventilation: a prospective observational multicenter study

Abstract

BackgroundPleural effusion is common during invasive mechanical ventilation, but its role during weaning is unclear. We aimed at assessing the prevalence and risk factors for pleural effusion at initiation of weaning. We also assessed its impact on weaning outcomes and its evolution in patients with difficult weaning.MethodsWe performed a prospective multicenter study in five intensive care units in France. Two hundred and forty-nine patients were explored using ultrasonography. Presence of moderate-to-large pleural effusion (defined as a maximal interpleural distance ≥ 15 mm) was assessed at weaning start and during difficult weaning.ResultsSeventy-three (29%) patients failed weaning, including 46 (18%) who failed the first spontaneous breathing trial (SBT) and 39 (16%) who failed extubation. Moderate-to-large pleural effusion was detected in 81 (33%) patients at weaning start. Moderate-to-large pleural effusion was associated with more failures of the first SBT [27 (33%) vs. 19 (11%), p < 0.001], more weaning failures [37 (47%) vs. 36 (22%), p < 0.001], less ventilator-free days at day 28 [21 (5–24) vs. 23 (16–26), p = 0.01], and a higher mortality at day 28 [14 (17%) vs. 14 (8%), p = 0.04]. The association of pleural effusion with weaning failure persisted in multivariable analysis and sensitivity analyses. Short-term (48 h) fluid balance change was not associated with the evolution of interpleural distance in patients with difficult weaning.ConclusionsIn this multicenter observational study, pleural effusion was frequent during the weaning process and was associated with worse weaning outcomes.Electronic supplementary materialThe online version of this article (10.1186/s13613-018-0446-y) contains supplementary material, which is available to authorized users.

Feasibility and efficacy of lung ultrasound to investigate pulmonary complications in patients who developed postoperative Hypoxaemia-a prospective study

“…A large pleural effusion was diagnosed when the maximal interpleural distance was more than 25 mm on ultrasonography, and the effusion must be visible in at least three intercostal spaces. Less than 15 mm of maximal interpleural distance was defined as a small effusion [22]. Combined with symptoms such as dyspnoea, a minimum of 3 B-lines in at least two anterior or lateral quadrants in each thorax may benefit from the consideration of pulmonary oedema [23].…”

Thoracic ultrasonography: a narrative review

“…Ultrasonography is superior to CXR for determining the presence of pleural fluid, estimating its volume, predicting the characteristics of the fluid, and in guiding pleural intervention [24][25][26][27][28][29]. Moderate to large pleural effusions are seen in up to one-third of patients at the initiation of ventilator weaning trials and are associated with higher rates of ventilator weaning failure as well as higher 28-day mortality rates [30].…”

Feasibility and Efficacy of Lung Ultrasound to Investigate Pulmonary Complications in Patients Who Developed Postoperative Hypoxaemia-A Prospective Study

“…Less than 15 mm of maximal interpleural distance was de ned as a small effusion. 23 Combined with symptoms such as dyspnoea, a minimum of 3 B-lines in at least two anterior or lateral quadrants in each thorax may bene t from the consideration of pulmonary oedema. 24 LUS scores (0-36, calculated by summing all 12 individual quadrant scores) are used to assess aeration changes, and a higher grade represents more serious aeration loss but is inapplicable for pneumothorax ( Figure 2).…”