Question
What are surfactants?
Answer
We use the term surface tension in respiratory because the definition of surface tension- is the pressure trying to collapse a bubble. Natural surfactants are produced in the body to reduce the surface tension in the lungs. Premature infants are often delivered before surfactant production has taken place naturally. When an infant is born premature, before 28 weeks gestation, there is not enough time for surfactant production in utero. In cases where this happens, we administer surfactant medications. Exogenous or artificial surfactants are indicated for infants with respiratory distress syndrome (RDS). When an infant is born prematurely, the job of the surfactant is to try to break the surface tension by keeping the lungs open so it is easier to ventilate. When we provide the infant with artificial surfactants, the infant can breathe in oxygen and exchange carbon dioxide, generally like a full-term.
All surfactant drug agents use the "surf" suffix. It lets us know we are talking about surfactant-type medications. Examples of surfactant medications like Beractant, Calfactant, Poractant Alfa are given via direct tracheal instillation. The patient is usually intubated and has an endotracheal tube in place during artificial surfactant administration. We can bag-mask ventilate or use the mechanical ventilator with a side port to instill the medication. We must administer the medicine directly to the lungs, saturating all the lobes with the surfactant. Something important to remember, and we need to be careful when doing so.
This Ask the Expert is an edited excerpt from the course, link to course here, Drug Agents for Respiratory Care, presented by Dr. Duane Reed, EdD, RRT, RCP.
