Question Answer
Laplace’s Law Physical principle describing and quantifying the relationship between the internal pressure of a drop or bubble, the amount of surface tensions, and the radius of the drop or bubble.
Prophylactic treatment Prevention of respiratory distress syndrome (RDS)in infents with very low birth weight and in infants with higher birth weight but with evidence of immature lungs, who are at risk for developing RDS.
Rescue Treatment Retroactive, or “Rescue”, treatment of infants who have developed RDS.
Surface tension Attraction of molecules in a liquid lining in lung tissue and the air, pulling the surface molecules inward.
Surfactant Agent that reduces surface tension.
Surfactant agents Regulate surface tension in films at gas-liquid interfaces. The interrelationship of surface tension, drop or bubble size, and pressure is described by leplaces law.
3 Exogenous surfactant agents/preperations currently used for Tx of nRDS Beractant (Survanta), Calfactant (Infasurf) and poractant alfa (Curosurf). These are modified natural agents.
What is Endogenous pulmonary surfactant made of? 90% lipids and 10% protein. The major phospholipid is Dipalmitoylphosphatidylcholine (DPPC)
Brand name of Beractant Survanta
Brand name of Calfactant Infasurf
Brand name of Poractant alfa Curosur
Beractant Dosage 8mL vial, 25 mg phospholipids/mL, 0.5-1.75 mg/mL triglycerides, 1.4-3.5 mg/mL free fatty acids, and <mg/mL protein. Dose: 100 mg phospholipids/kg (4mL) in four divided doses via ET tube.
Calfactant Dosage 3-mL and 6-mL vial, 35 mg phospholipids/mL, 0.65 mg proteins. Dose: 3mL/kg in two divided doses of 1.5 mL/kg via ET tube.
Poractant alfa Dosage 1.5-mL vial, 80 mg phospholipids, with 1 mg of proteins, or 3 mL vial, 160 mg phospholipids, with 2 mg of proteins. Dose: 2.5 mL/kg (200 mg/kg) in two divided doses via ET tube.
What surfactant-associated proteins regulate endogenous pulmonary surfactant function? SP-A SP-B SP-C
Exogenous Surfactant enters: the Lamellar bodies, whereby replacing natural surfactant that is deficent.
What 2 ways is surfactant given? Prophylactiaclly in RDS or as rescure TX
Exogenous Surfactant therapy possible hazards AW occlusion, desaturation, bradycardia, overoxygenation and overinflation, apnea and pulmonary hemmorage.