An updated study-level meta-analysis of randomised controlled trials on proning in ARDS and acute lung injury

Abstract

IntroductionIn patients with acute lung injury (ALI) and/or acute respiratory distress syndrome (ARDS), recent randomised controlled trials (RCTs) showed a consistent trend of mortality reduction with prone ventilation. We updated a meta-analysis on this topic.MethodsRCTs that compared ventilation of adult patients with ALI/ARDS in prone versus supine position were included in this study-level meta-analysis. Analysis was made by a random-effects model. The effect size on intensive care unit (ICU) mortality was computed in the overall included studies and in two subgroups of studies: those that included all ALI or hypoxemic patients, and those that restricted inclusion to only ARDS patients. A relationship between studies' effect size and daily prone duration was sought with meta-regression. We also computed the effects of prone positioning on major adverse airway complications.ResultsSeven RCTs (including 1,675 adult patients, of whom 862 were ventilated in the prone position) were included. The four most recent trials included only ARDS patients, and also applied the longest proning durations and used lung-protective ventilation. The effects of prone positioning differed according to the type of study. Overall, prone ventilation did not reduce ICU mortality (odds ratio = 0.91, 95% confidence interval = 0.75 to 1.2; P = 0.39), but it significantly reduced the ICU mortality in the four recent studies that enrolled only patients with ARDS (odds ratio = 0.71; 95% confidence interval = 0.5 to 0.99; P = 0.048; number needed to treat = 11). Meta-regression on all studies disclosed only a trend to explain effect variation by prone duration (P = 0.06). Prone positioning was not associated with a statistical increase in major airway complications.ConclusionsLong duration of ventilation in prone position significantly reduces ICU mortality when only ARDS patients are considered.

Benefícios do decúbito ventral associado ao CPAP em recém-nascidos prematuros

“…Além da pressão positiva, o posicionamento em decúbito ventral do recém-nascido prematuro pode contribuir na melhora da oxigenação e melhora na mecâ-nica respiratória. Em pacientes adultos, pediátricos e neonatais já foi amplamente listado os benefícios do decúbito ventral [8][9][10][11][12] . Os resultados são justificados pela melhora na relação ventilação/perfusão devido à maior área de troca gasosa e menor compressão do coração no parênquima pulmonar com colocado no decúbito ventral 10 .…”

Extracorporeal Life Support for Acute Respiratory Failure. A Systematic Review and Metaanalysis

“…Currently, lung-protective pressureand volume-limited ventilatory strategies aimed at mitigating ventilator-associated lung injury have become the standard of care (2). Clinical trials evaluating the use of higher positive end-expiratory pressure, recruitment maneuvers, high-frequency oscillatory ventilation, and prone positioning to further optimize lung protection in patients with ARDS have yielded variable results (4)(5)(6)(7)(8)(9)(10)(11).…”

Prone Positioning of Patients With Acute Respiratory Distress Syndrome

“…25 Decreased ventilation of dependent areas with the patient supine is abolished when the patient is prone, allowing more homogeneous ventilation and perfusion, which reduces the shunt. 25,26 Positive-pressure ventilation amplifies this effect while the patient is prone by directing the pulmonary blood flow to the more ventilated regions. 25 Postural drainage of water and exudates and accelerated removal of secretions are also noted clinical benefits of positioning patients prone.…”

“…These complications include, but are not limited to, adverse airway events, displacement of the endotracheal tube, selective intubation or accidental extubation, obstruction of the endotracheal tube, pressure sores or facial edema, and dislodgement of catheters or tubes. 25,26,32,36 Hemodynamic instability, worsening gas exchange, patients' intolerance owing to inadequate sedation, cardiac dysrhythmia, and inadequate enteral nutrition also may occur. 37 Difficulty in monitoring the patient and performing cardiopulmonary resuscitation are additional complications of prone positioning.…”