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Published on: September 29, 2020
Reference intervals for end-tidal carbon monoxide of preterm neonates
Sasikarn Pakdeeto1,2, Thomas R Christensen3, Timothy M Bahr4,5,6
1Ramathibodi Hospital and Chakari Nareubodindra Institute, Bangkok, Thailand.
Objectives:
We constructed reference intervals for end-tidal carbon monoxide (ETCOc) levels of neonates 28 0/7 to 34 6/7 weeks gestation in order to assess hemolytic rate.
Study Design:
This is a prospective four-NICU study in Bangkok, Thailand, and Utah, USA.
Results:
Of 226 attempted measurements, 92% were successful. Values from day 1 through 28 were charted and upper (>95th percentile) reference interval limits calculated. During the entire 28 days, the ETCOc upper reference intervals from babies in Bangkok were higher than those in Utah (p < 0.01). No differences were found due to sex, or earliest vs. latest gestation at birth (both p > 0.1). Similar to term neonates, preterm neonates in Bangkok and Utah had higher ETCOc values during the first 48 h after birth than thereafter (p < 0.01).
Conclusions:
Using this methodology, and the reference interval chart, the hemolytic rate of preterm infants ≥28 weeks can be assessed.
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