title: The prone position is associated with a decrease in respiratory system compliance in healthy anaesthetized infants.
abstract: Ten healthy (ASA I or II) anaesthetized infants undergoing clubfoot surgery were studied. General anaesthesia included rocuronium, nitrous oxide and isoflurane. Volume controlled ventilation (12 ml.kg-1) was delivered via a coaxial Mapleson-D (Bain) system and a Datex AS/3 ventilator. Pulmonary mechanics were measured sequentially in the supine and prone positions using a Bicore CP-100 pulmonary function monitor. Subjects had a mean age of 6 (+/- 2) months and a mean weight of 8.3 (+/- 1.4) kg. Dynamic compliance (CDYN) and static compliance (CSTAT) were both significantly lower in the prone position than in the supine position (P < 0.0005). Mean CDYN decreased from 14.9 +/- 4.9 ml.cmH2O-1 (supine) to 11.6 +/- 3.5 ml.cmH2O-1 (prone). Mean CSTAT decreased from 10.2 +/- 2.8 ml.cmH2O-1 (supine) to 8.9 +/- 2.3 ml.cmH2O-1 (prone). No clinically significant differences in gas exchange were noted, however, on repositioning.
authors.affiliation: Alberta Children's Hospital, University of Calgary, 1820 Richmond Road SW, Calgary, Alberta, T2T 5C7, Canada. robin.cox@crha-health.ab.ca
authors.forename: R G
authors.initials: RG
authors.lastname: Cox
authors.forename: A
authors.initials: A
authors.lastname: Ewen
authors.forename: B B
authors.initials: BB
authors.lastname: Bart
mesh_terms: D000768:Anesthesia, General; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007223:Infant; D008170:Lung Compliance / Q000502:physiology*; D008297:Male; D016684:Prone Position / Q000502:physiology*; D011659:Pulmonary Gas Exchange / Q000502:physiology; D015656:Respiratory Mechanics / Q000502:physiology; D016683:Supine Position / Q000502:physiology