Figure 2

Ventilation parameters set by the anesthesia provider; Ventilation parameters set by the anesthesia provider over time (2005–2013) at five U.S. academic medical centers. At top left, average of median exhaled tidal volume per kilogram of predicted body weight (PBW). At top right, percentage of cases utilizing positive end expiratory pressure (PEEP). At bottom left, average of median respiratory rate (RR). At bottom right, average of median fraction of inspired oxygen (FiO₂). Error bars indicate 25^th and 75^th percentile ranges.