Association between early cumulative fluid balance and successful liberation from invasive ventilation in COVID-19 ARDS patients — insights from the PRoVENT-COVID study: a national... od Sanchit Ahuja, Harm-Jan de Grooth, Frederique Paulus, Fleur L. van der Ven, Ary Serpa Neto, Marcus J. Schultz, Pieter R. Tuinman, PRoVENT-COVID Study Collaborative Group* ‘PRactice of VENTilation in COVID–19’