Flow Index: a novel, non-invasive, continuous, quantitative method to evaluate patient inspiratory effort during pressure support ventilation di Albani, F, Pisani, L, Ciabatti, G, Fusina, F, Buizza, B, Granato, A, Lippolis, V, Aniballi, E, Murgolo, F, Rosano, A, Latronico, N, Antonelli, M, Grasso, S, Natalini, G