Cautionary tales from the neonatal intensive care unit: diapers may mislead urinary output estimation in extremely low birthweight infants.

Objective: To examine the validity of the weighing of modern polyacrylate diapers to determine urine output in the extremely low birth weight infant nursed in a humidified incubator.

Design: Observational study with repeated measures using high-absorbency cellulose/polyacrylate diapers and a humidified incubator in a modeled clinical scenario.

Setting: A tertiary referral neonatal intensive care unit.