Surfactant Flashcards
What is Surfactant
–production and regulation of surfactant secretion
–it is already in the body
–Recycling activity
Function of Surfactant
–prevent alveolar collapse
–enables the lung to expand easily
–prevents leakage of fluid from the alveolar-capillary membrane
–it lowers the surface tension in alveoli
Endogenous Surfactant
–naturally produced in the lungs
Exogenous Surfactant
–prepared outside patient’s own body
Uses of Exogenous Surfactant
–Treatment or prevention of Respiratory Distress Syndrome (RDS) in newborns
–RDS is associated with prematurity and low birth weight
–type II cells are not mature enough to produce surfactant
–inadequate surfactant leads to alveolar collapse, hypoxemia
–increased WOB
Natural Exogenous
–obtained from animals
Synrhetic Exogenous
–produced in a lab
Synthetic Natural
–prepared in vitro by genetic engineering
Natural Exogenous Surfactant Drugs
–Beractant (Survanta)
–Poractant Alfa (Curosurf)
–Calfactant (Infasurf)
Exogenous Synthetic Surfactant Drugs
–Lucinactant (Aerosurf)
–is aerosolized
Exogenous Surfactants: Beractant
–Trade Name: Survanta
–A modified natural surfactant (bovine): cow lung
–Indication Use: prophylactic therapy of premature infants weighing less than 1250 grams at birth or with evidence of surfactant deficiency and risk or RDS
–Given within 15min of birth or ASAP
–Treatment: infants with evidence of RDS
-agent should be given within 8hr of birth
–Method of Admin: 4ml/kg birth weight
-Instilled in ETT Q6H, up to 4 doses
-Do Not Shake
-let stand at room temp for 20min
–Instilled into the trachea through the endotracheal tube
-Given in 4 doses from a syringe
-during each quarter dose, the infant is placed in a different position
Exogenous Surfactants: Calfactant
–Trade Name: Infasurf
–Modified natural surfactant (bovine): cow lung
–Indications:
-prevention (prophylaxis) of RDS in premature infants less than 29 weeks of gestational age and at high risk for RDS
–no more than 30 mins after birth
–Treatment: rescue of premature infants less than or equal to 72 hrs of age who develop Rds and require endotracheal intubation
–Dosage: 3ml/kg weight at birth, delivered over 2 doses
-Instilled in ETT every 12hr, up to 3 doses
–Method of Admin: warm to room temp, catheter adminstration
Exogenous Surfactants: Poractant
–Trade Name: Curosurf
–natural surfactant(porcine): pig lung
–Indication use: treatment rescue of premature infants with RDS, thus reducing mortality and pneumothoraces
-severe meconium aspiration syndrome in term infants
-respiratory failure caused by group B streptococcal infection in neonates
–Dosage: 2.5mL/kg birth weight
-2 subsequent doses of 1.25 ml/kg birth weight Q12H
-Maximum recommended total dose id 5 mL/kg
–Administration: warm to room temp, catheter admin in 2 aliquots
-Alternately: full dose can be given using a dual lumen tube over 1min in neutral position
Surfactant Admin.
–most surfactants should be warmed before administering via gentle shaking and rubbing the bottle
–Patient’s ETT should be suctioned first
–a sterile technique is used thru a catheter that is inserted into the ETT via special adapter
–Patient should be bagged a few breaths after instillation
–Dosages are divided into equal aliquots
–Each aliquots is given while patient is in different position
–No suctioning is allowed for several hrs
–head of bed should be up directly after instillation
Mode of Action Surfactant
–replace and replenish deficient endogenous surfactant pool neonatal RDS
–can be recycled into type II cells and form a surfactant pool to regulate surface tension
