The Effect of High Humidity Environments on Very Low Birth Weight Preterm Infants: A Systematic Review

Abstract

The scholarly evidence on the timing and practice of interventional care administered to preterm infants in high-humidity environments is unclear. This makes evaluating the prognosis of preterm infants with comorbidities difficult and means that clinical medical staff lack clear guidelines for care. This systematic review was designed to explore the prognostic effects of interventions for comorbidities performed on very low birthweight preterm infants in high humidity environments to provide an empirical basis for developing related clinical-care guidelines. An electronic database was searched for all relevant documents published between 1930 and September 2021. The keywords used were "premature infants" OR "very low weight premature infants" OR "very low weight premature infants" AND "humidity", and the target groups were premature infants weighing ≤ 1,500 grams or delivered at ≤ 34 weeks of gestation. The timing and practice of interventions in high humidity environments and the occurrence and prognosis of related comorbidities were explored. The main findings cover the issues of body weight, total water intake, electrolytes, urine output, insensitivity water loss, infection, common complications, and mortality in preterm infants. After reviewing the methods, quality, and efficacy of the research in the identified studies, 9 articles were selected for integrated synthesis. Recommendations for the use of high humidity with infants delivered at ≤ 30 weeks of gestation or at birth weights ≤ 1,000 grams were integrated. An environment with a relative humidity of 70%-80% should be used during the first postpartum week and 50%-60% during the second postpartum week. The recommended total duration of use of a high-humidity environment is two weeks to avoid delaying the development of the stratum corneum. Physiological indicators shown to exhibit significant improvement under this regimen include reduced total water intake, increased urine output, and a lower incidence of hypernatremia. The appropriate timing and practice of high humidity intervention were integrated in this study. It is hoped that this review provides an evidence-based clinical practice guideline for preterm infant care.