Respiratory mechanics in very low birth weight infants during continuous versus intermittent gavage feeds

This study was designed to determine whether respiratory mechanics in stabl e, very low birth weight infants changed after replacing intermittent feeds with continuous feeding. We measured static respiratory system compliance, respiratory system resistance, functional residual capacity (FRC), and tid al volume immediately before feeds and at 20, 60, and 120 min after feeds, and again the next day on continuous feeds. Patients selected for enrollmen t into the study needed to fulfill the following criteria: 1) birth weight and postnatal weight < 1,500 g, 2) no need for mechanical ventilation, posi tive airway pressure, or supplemental oxygen, 3) receiving and tolerating a t least 100 mL/kg/day of intermittent gavage feeds, and 4) no change in met hylxanthine or diuretic dosage for 3 days before the study. Respiratory mec hanics were measured using the SensorMedics 2600 Pediatric Pulmonary Cart ( Yorba Linda, CA). We studied 16 infants (gestational age 28.3 +/- 3.7 weeks , mean SD) at a postnatal age of 10-82 days. The average interindividual coefficient of variance was 20 +/- 2% for stati c compliance, 35 +/- 6% for resistance, 18 +/- 3% for FRC, and 19 +/- 3% fo r tidal volume. Repeated-measures analysis of variance did not reveal any s ignificant difference in respiratory mechanics with intermittent vs. contin uous feeding. The data suggest that static respiratory mechanics in stable, very low birt h weight infants are not affected by changing enteral feeds from intermitte nt gavage to a continuous schedule. (C) 2001 Wiley-Liss, Inc.