title: Lung function in immature baboons with respiratory distress syndrome receiving early caffeine therapy: a pilot study.
abstract: OBJECTIVE
  The cardiopulmonary effects of early caffeine therapy in surfactant-treated immature baboons were measured.
  
  
  METHODS
  Nine 125-d (term = 185 d) baboons receiving caffeine citrate at 1 and 12 h age as part of a pilot study on the use of nasal CPAP at 24 h were compared to six untreated animals destined for prolonged ventilator support. All received surfactant prior to their first breath and again at 6 h age. Serial physiologic and ventilatory parameters were recorded. Lung mechanics were measured by body plethysmography. Data were compared from 1 through 24 h age.
  
  
  RESULTS
  There were no between-group differences in any study variables prior to caffeine therapy at 1 h age. Airway resistance (RA) was significantly lower in caffeine-treated compared to non-caffeine-treated animals at 12 and 24 h age [median (range)12 h: 47 (35-107) cm H2O/l/s to 135 (120-259) cm H2O/l/s; and 24 h: 93(60-137) cm H2O/l/s to 211 (86-235) cm H2O/l/s; p < 0.05]. Respiratory system compliance (CRS) was higher in caffeine-treated compared to non-caffeine-treated animals at 18 and 24 h age [median (range) 18 h: 0.60 (0.29-1.58) ml/cm H2O/kg to 0.39 (0.33-0.46) ml/cm H2O/kg; and 24 h: 0.68 (0.36-1.20) ml/cm H2O/kg to 0.36 (0.33-0.55) ml/cm H2O/kg; p < 0.05]. Ventilatory efficiency index and arterial/alveolar ratio significantly improved in caffeine-treated animals over the 24-h study period (p < 0.05, repeated measures ANOVA).
  
  
  CONCLUSIONS
  In this pilot study, early caffeine treatment, combined with prophylactic surfactant therapy, was associated with better lung function during the initial 24 h of life. This combined approach may facilitate earlier extubation or prophylactic efforts to support infants on nasal CPAP. Randomized, controlled investigation is warranted.
authors.affiliation: Department of Medicine and Physiology, University of Texas Health Science Center, San Antonio, Texas 78284, USA. yoderb@uthscsa.edu
authors.forename: B
authors.initials: B
authors.lastname: Yoder
authors.forename: M
authors.initials: M
authors.lastname: Thomson
authors.forename: J
authors.initials: J
authors.lastname: Coalson
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001688:Biological Products / Q000627:therapeutic use*; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D002110:Caffeine / Q000627:therapeutic use*; D002951:Citrates / Q000627:therapeutic use*; D045422:Continuous Positive Airway Pressure; D004195:Disease Models, Animal; D004338:Drug Combinations; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008168:Lung / Q000503:physiopathology; D008297:Male; D010215:Papio; D010743:Phospholipids / Q000627:therapeutic use*; D010865:Pilot Projects; D011663:Pulmonary Surfactants / Q000627:therapeutic use*; D012127:Respiratory Distress Syndrome, Newborn / Q000503:physiopathology / Q000628:therapy*; D012129:Respiratory Function Tests; D015656:Respiratory Mechanics / Q000502:physiology; D016896:Treatment Outcome
chemical_list: D001688:Biological Products; D001993:Bronchodilator Agents; D002951:Citrates; D004338:Drug Combinations; D010743:Phospholipids; D011663:Pulmonary Surfactants; D002110:Caffeine; C068291:poractant alfa; C026189:caffeine citrate