Objective: To compare fluid and electrolyte management in extremely low birth weight (ELBW) infants nursed in humidified versus nonhumidified incubators.
Study design: Setting--tertiary intensive care nursery. Subjects--all infants with birth weight < 1000 g admitted 1/95 to 1/99 who were treated with incubators and survived for > 96 hours (N = 155). Intervention--retrospective comparison of daily weights, fluid intakes, urine outputs, and serum electrolytes between group 1 (n = 70, nonhumidified incubators, born 1/95 to 1/97) and group 2 (n = 85, humidified incubators, born 1/97 to 1/99) over the first 4 days after birth.
Results: Despite similar daily weight losses between groups, group 1 infants received higher fluid intakes, had lower urine outputs, and had a higher incidence of hypernatremia, hyperkalemia, and azotemia (p < 0.05). Although no differences in mortality or the incidence of patent ductus arteriosus, bronchopulmonary dysplasia, or the overall rate of nosocomial infections were observed, the proportion of gram-negative isolates increased significantly (62%, p < 0.05) following the introduction of humidified incubators.
Conclusions: ELBW weight infants nursed in humidified incubators have lower fluid requirements, improved electrolyte balance, and higher urine outputs during the first 4 days after birth compared to those nursed in nonhumidified incubators.