Inclusion Criteria:  Adult patients age ≥18 years with acute respiratory failure receiving invasive mechanical ventilation Managed in pressure-support mode of ventilation  Exclusion Criteria:  Actively undergoing a spontaneously awakening trial or SAT Patient or surrogate is unable to provide informed consent Currently pregnant Currently incarcerated Acute exacerbation of an obstructive lung disease Known esophageal varices or any other condition for which the attending physician deems an orogastric catheter to be unsafe Esophageal, gastric or duodenal surgical procedures within the last 6 months