A nurse administers chloral hydrate to Kaitlyn in a dark, quiet room while she is being monitored continuously for heart rate, respiratory rate, and pulse oximetry. Once Kaitlyn is asleep, a respiratory therapist helps Dr Smith place the pneumatic vest around her. Kaitlyn continues to be monitored with pulse oximetry, and the respiratory therapist watches closely throughout the procedure. A tight-fitting mask is placed over Kaitlyn’s nose and mouth, attached to a pneumotachometer. On a computer monitor, Dr Smith is able to track flow/volume loops generated by Kaitlyn’s tidal breathing. The low-volume point in these tracings is deemed to be the infant’s FRC. Once this is determined, the computer assists in timing the inflation of the pneumatic vest around Kaitlyn’s chest, just as she is nearing the end of an inhalation (although sometimes manual timing is needed). With the respiratory therapist’s assistance, this is repeated three times, each time generating a partial-flow-volume loop. From time to time, the respiratory therapist makes sure that there is a tight seal over Kaitlyn’s nose and mouth. The jacket pressure is increased until the flows no longer increase. The maximum flow at FRC is calculated and found to be consistent from trial to trial. Fortunately for Kaitlyn, Dr Smith finds that it is well within normal range for an infant of her length. Dr Smith also notes that the partial-flow-volume loop shows no concavity, suggesting that there is no limitation of the small-airways flow. The team also plans to obtain a raised-volume-flow volume loop. Kaitlyn’s lungs are passively inflated using the face mask, and the pneumatic vest is again inflated, this time at an elevated lung volume of 30 cm H2O pressure. Unfortunately, Kaitlyn awakens with this maneuver. Dr Smith makes the clinical decision not to resedate her, deeming that there is sufficient information already. Kaitlyn is then observed and monitored by the nursing staff until completely awake, then permitted oral feeds.