title: Dosing of porcine surfactant: effect on kinetics and gas exchange in respiratory distress syndrome.
abstract: OBJECTIVE
  The goal was to study exogenous surfactant disaturated phosphatidylcholine (DSPC) kinetics in preterm infants with respiratory distress syndrome (RDS) who were treated with 100 or 200 mg/kg porcine surfactant.
  
  
  METHODS
  Sixty-one preterm infants with RDS undergoing mechanical ventilation received, within 24 hours after birth, 100 mg/kg (N = 40) or 200 mg/kg (N = 21) porcine surfactant mixed with [U-(13)C]dipalmitoylphosphatidylcholine. Clinical and respiratory parameters were recorded, and DSPC half-life and pool size and endogenous DSPC synthesis rate were calculated.
  
  
  RESULTS
  Clinical characteristics and short-term outcomes did not differ between groups. In the 100 mg/kg group, 28 infants (70%) received a second dose after 25 +/- 11 hours and 9 (22.5%) a third dose after 41 +/- 11 hours; in the 200 mg/kg group, 6 infants (28.6%) received a second dose after 33 +/- 8 hours and 1 a third dose. The DSPC half-life was longer in the 200 mg/kg group (first dose: 32 +/- 19 vs 15 +/- 15 hours [P = .002]; second dose: 43 +/- 32 vs 21 +/- 13 hours [P = .025]). DSPC synthesis rates and pool sizes before the first and second doses did not differ between the groups. The 200 mg/kg group exhibited a greater reduction in the oxygenation index than did the 100 mg/kg group after the first (P = .009) and second (P = .018) doses.
  
  
  CONCLUSIONS
  Porcine surfactant given to preterm infants with RDS at a dose of 200 mg/kg resulted in a longer DSPC half-life, fewer retreatments, and better oxygenation index values.
authors.affiliation: Departments of Pediatrics, University of Padua, Padua, Italy. cogo@pediatria.unipd.it
authors.forename: Paola Elisa
authors.initials: PE
authors.lastname: Cogo
authors.forename: Maddalena
authors.initials: M
authors.lastname: Facco
authors.forename: Manuela
authors.initials: M
authors.lastname: Simonato
authors.forename: Giovanna
authors.initials: G
authors.lastname: Verlato
authors.forename: Clementina
authors.initials: C
authors.lastname: Rondina
authors.forename: Aldo
authors.initials: A
authors.lastname: Baritussio
authors.forename: Gianna Maria
authors.initials: GM
authors.lastname: Toffolo
authors.forename: Virgilio Paolo
authors.initials: VP
authors.lastname: Carnielli
mesh_terms: D001688:Biological Products / Q000008:administration & dosage* / Q000493:pharmacokinetics; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000188:drug therapy* / Q000503:physiopathology; D010713:Phosphatidylcholines / Q000493:pharmacokinetics; D010743:Phospholipids / Q000008:administration & dosage* / Q000493:pharmacokinetics; D011659:Pulmonary Gas Exchange / Q000187:drug effects; D011663:Pulmonary Surfactants / Q000008:administration & dosage* / Q000493:pharmacokinetics; D012121:Respiration, Artificial; D012127:Respiratory Distress Syndrome, Newborn / Q000188:drug therapy* / Q000503:physiopathology; D014132:Trachea / Q000378:metabolism
chemical_list: D001688:Biological Products; D010713:Phosphatidylcholines; D010743:Phospholipids; D011663:Pulmonary Surfactants; C017463:lecithins, disaturated; C068291:poractant alfa