Pulmonary distribution of lucinactant and poractant alfa and their peridosing hemodynamic effects in a preterm lamb model of respiratory distress syndrome.
Tracheal instillation of surfactant to premature newborns improves their survivability but may transiently obstruct airways resulting in undesirable acute effects on cerebral blood flow (CBF) and oxygenation. The acute peridosing hemodynamic effects of surfactant administration may be avoided by minimizing the volume of surfactant administered, but smaller surfactant volumes may also result in less even distribution of surfactant throughout the lung. These experiments were undertaken to compare responses to two surfactants with different dose volumes (porcine-derived poractant alfa, 2.5 mL/kg vs peptide-based synthetic lucinactant, 5.8 mL/kg) given to newly delivered lambs at 85% gestation. Both surfactants resulted in similar improvements in blood gas values, a doubling of dynamic compliance, increases in brain tissue oxygen tension, and stable blood pressure with no significant change in CBF. Distribution of surfactant throughout the lungs was more uniform with lucinactant than poractant alfa when assessed by labeled microspheres. We conclude that improvements in lung mechanics, gas exchange, and changes in CBF are comparable for a porcine-derived and peptide-containing synthetic surfactant, despite instilled volumes differing by 2-fold. Intrapulmonary distribution of surfactant is more uniform after a larger volume is instilled.
Department of Respiratory Care, Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA 92354, USA.
Michael H
MH
Terry
T A
TA
Merritt
Benjamin
B
Harding
Hobe
H
Schroeder
Jeanette
J
Merrill-Henry
Jan
J
Mazela
Timothy J
TJ
Gregory
Robert
R
Segal
Gordon G
GG
Power
Arlin B
AB
Blood
D000704:Analysis of Variance; D000818:Animals; D001688:Biological Products / Q000494:pharmacology* / Q000627:therapeutic use; D001784:Blood Gas Analysis; D001794:Blood Pressure / Q000187:drug effects; D001921:Brain / Q000378:metabolism; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D005233:Fatty Alcohols / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D007231:Infant, Newborn; D008168:Lung / Q000187:drug effects / Q000502:physiology; D008863:Microspheres; D010100:Oxygen / Q000378:metabolism; D010715:Phosphatidylglycerols / Q000494:pharmacology* / Q000627:therapeutic use; D010743:Phospholipids / Q000494:pharmacology* / Q000627:therapeutic use; D011506:Proteins / Q000494:pharmacology* / Q000627:therapeutic use; D011663:Pulmonary Surfactants / Q000494:pharmacology* / Q000627:therapeutic use; D012127:Respiratory Distress Syndrome, Newborn / Q000188:drug therapy / Q000378:metabolism*; D012756:Sheep
D001688:Biological Products; D004338:Drug Combinations; D005233:Fatty Alcohols; D010715:Phosphatidylglycerols; D010743:Phospholipids; D011506:Proteins; D011663:Pulmonary Surfactants; C502722:lucinactant; C068291:poractant alfa; D010100:Oxygen