Nebulized Epinephrine Essay

INTRODUCTION
Nebulized epinephrine has been a recognized therapy for the treatment of moderate to severe croup for some time1-8. It is believed that the alpha adrenergic action may constrict the small vessels in the larynx and relieve the symptoms9 9. Whether or not the beta adrenergic effect is beneficial is open to debate in infants10 While the onset of action is rapid, the administration system is cumbersome and almost always intermittent. This results in an immediate effect that lasts an indefinite but often very short time. The Vapotherm system (Stevensville, MD)11;12 uses a cartridge of tubules that are permeable to water vapour to humidify hospital air (or oxygen). It is designed to provide high levels of humidity to the airway continuously for long periods. The water, cartridge and air are heated to body temperature or slightly above and a triple lumen tube that goes to the

The child immediately improved and was stable on continuous delivery for many hours. When the source of the humidified water was switched to a Vapotherm system at the same flow (10 L/min) but not containing epinephrine, the child’s croup worsened, only to improve again when epinephrine was added to the humidifying water. A similar experience was found with a second child with croup which led to the hypothesis that epinephrine may be deliverable in the vapour phase as opposed to droplets as has been the usual method with a nebulizer. It also appeared that the improvement in upper airway obstruction was not due (at least alone) to the high flow delivering continuous positive airway pressure, as originally theorized by Klein and