title: Effect of continuous negative extrathoracic pressure on respiratory mechanics and timing in infants recovering from neonatal respiratory distress syndrome.
abstract: Changes in respiratory mechanics and timing produced by continuous negative extrathoracic pressure (CNEP) of -0.6 kPa were assessed in 18 infants recovering from neonatal respiratory distress syndrome. The median gestational age was 28 wk (range 24-36 wk). All infants were recruited before discharge from neonatal intensive care and were measured at a median postnatal age of 58 d (range 10-127 d) and a median weight of 2.67 kg (range 1.99-3.77 kg). All had been treated for respiratory distress syndrome; 11 were diagnosed as having chronic lung disease. At the time of the study, all infants were stable breathing room air. There was a significant decrease of the respiratory rate in all but one infant from 63.6 +/- 10.0 to 49.3 +/- 9.1 breaths per min (mean +/- SD) during CNEP. This was predominantly due to a marked prolongation of the expiratory time. Passive respiratory mechanics were assessed using airway occlusion techniques. Whereas respiratory system compliance (Crs) did not change in the infants with a normal baseline measurement, there was a significant improvement of Crs in the 11 infants with low Crs values in atmosphere: In the latter, all of whom were very-low-birth-weight infants, Crs assessed by the multiple occlusion technique (mean +/- SD) corrected for body weight increased from 7.9 +/- 1.5 to 9.4 +/- 1.9 mL.kPa-1.kg-1 in CNEP (p = 0.012). There was no consistent change in respiratory system resistance in this population of 18 infants.(ABSTRACT TRUNCATED AT 250 WORDS)
authors: Portex Anaesthesia, Intensive Therapy and Respiratory Medicine Unit, Institute of Child Health, London, United Kingdom.
authors: M
authors: M
authors: Gappa
authors: K
authors: K
authors: Costeloe
authors: D P
authors: DP
authors: Southall
authors: P S
authors: PS
authors: Rabbette
authors: J
authors: J
authors: Stocks
mesh_terms: D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008176:Lung Volume Measurements; D008297:Male; D012127:Respiratory Distress Syndrome, Newborn / Q000503:physiopathology / Q000628:therapy*; D015656:Respiratory Mechanics / Q000502:physiology*; D013997:Time Factors; D015919:Ventilators, Negative-Pressure