Aim: To compare sanitary napkins and absorbent nappy pads (ANP) for urine output (UO) measurement.
Methods: Phase 1: Freshly passed neonatal urine (5, 10 and 15 mL) was poured onto preweighed sanitary napkins or ANP, which were juxtaposed to the genital area of manikins placed in incubators/warmers and weighed at (1/2), 1, 2, 4, 5 and 6 hr. Outcome was percentage weight change from baseline. Phase 2: Five very low birth weight boys in incubators had UO measurement by test tubes. A sanitary napkin or ANP was co-applied with the test tube for 4 h each. Urine collected in the test tube was measured and poured on the device, which was reapplied. Weight and wetness were checked.
Results: Phase 1: Mean urine loss was 8.35, 13.8, 20.1, 25.2, 33.1, 38.7 and 42.6% at (1/2), 1, 2, 3, 4, 5 and 6 h, respectively (repeated measures ANOVA [RM-ANOVA], p < 0.001). Loss was higher with ANP than sanitary napkins (32.1% vs. 13.4%, two-way RM-ANOVA, p = 0.001). There was less loss in incubators versus radiant warmers at 6 h (p = 0.09). Phase 2: There was 12.1 and 26% deficit with sanitary napkin and ANP, respectively. Wetness was felt in one and four cases, respectively.
Conclusion: Urinary losses are less from sanitary napkins than ANPs.