Respiratory Care Pharmacology Chapter 10: Surfactant Agents

pulmonary surfactant

mixture of lipids and proteins that covers the entire alveolar surface of the lungs. Reduces surface tension at the air-liquid interface throughout the lung

10% proteins

90% lipids

what percent of surfactant is protein, and what percent is lipids?

Type II alveolar cells

what cells produce surfactant?

Laminar bodies

vesicles that store surfactant are called...

True

True or False: surfactant reduces surface tension, which will prevent alveolar collapse at end-expiration.

-Deficiency of endogenous pulmonary surfactant

-RDS in premature infants

name 2 indications for administration of exogenous surfactant

30 weeks

surfactants are administered to premature infants less than ___ weeks of gestational age

surface tension

force caused by attraction between like molecules that occurs at liquid-gas interfaces and holds liquid surface intact

True

True or False: Surfactant are like soaps or detergents

LaPlace's Law

_______________ states that the higher the surface tension of the liquid lining, the greater the compressing force inside the alveolus

decreased compliance

How does increased surface tension affect compliance?

increased elasticity

how does increased surface tension affect elasticity?

endogenous surfactant

surfactant made naturally by the body are called...

exogenous surfactants

surfactant drugs prepared outside the patients' body are called

-other humans

-animals

-laboratory synthesis

name 3 ways exogenous surfactants are prepared

True

True or False: surfactants are prophylactically indicated for prevention of RDS in infants with very low birth weights

yes, if there is evidence of immature lungs

Can surfactants be indicated for normal weight infants?

-Natural (modified) surfactant

-Synthetic surfactant

-Synthetic-natural surfactant

name the 3 types of exogenous surfactant preparations

no

do any synthetic-natural surfactants exist at this time?

-Natural modified

-Cow (Bovine)

-Beractant

-4mg/kg

give the type, source, generic name, and dosage of Survanta

-Natural modified

-Cow (Bovine)

-Calfactant

-3mg/kg

give the type, source, generic name, and dosage of Infasurf

-Natural

-Pig (Porcine)

-Poractant alfa

Initial: 2.5 mg/kg

Subsequent: 1.25 mg/kg

give the type, source, generic name, and initial/subsequent dosage of Curosurf

-Synthetic

-Lucinactant

give the type and generic name for Surfaxin

Beractant (Survanta)

this specific surfactant is indicated for prophylactic therapy of premature infants weighing less than 1250 grams at birth with evidence of surfactant deficiency and risk of RDS, and rescue treatment of infants with evidence of RDS

True

True or False: Exogenous surfactants can be recycled into type II cells and form a surfactant pool to regulate surface tension

-increase in oxygenation

-increase in FRC

-increase in compliance

name 3 clinical outcomes of surfactant administration

large volumes of surfactant in neonatal sized airways can cause airway obstruction, desaturation, and bradycardia

why must surfactant be administered in small volumes?

Retinopathy of Prematurity; Titrate FiO2 down

what is the risk of surfactant causing the infant's PaO2 to increase too high? how would we prevent this?