Comparative Study on Relative Humidity of Non-Humidified and Humidified Infant Incubators in Maharat Nakhon Ratchasima Hospital

Abstract

Background: Protecting newborn infant against heat loss is one of factors to improve survival rate. Recently premature infants have been cared in servo control incubators. Evaporated heat loss is increased when relative humidity of incubator is decreased. Objective: To measure relative humidity of intensive care unit and of non-humidified and humidified infant incubators. Methods: From November 2002 to October 2003, temperature and relative humidity in newborn intensive care unit (NICU), relative humidity of Air-Shields and Atom double wall servo control incubator were measured at air temperature between 29 to 35^oC with or without sterile water filled. Results: Relative humidity in NICU was highest in rainy season (59.3%) and lowest in winter (44.6%). Relative humidity of incubator was decreased when air temperature was increased (P<0.001) and highest in rainy season, lowest in winter. Relative humidity increased significantly (P<0.001) after sterile water was filled. There was no difference according to type of incubatore. Conclusion: Relative humidity of infant incubators inversely related to temperature of incubator and relative humidity of NICU varied among seasons.