Sasikarn Pakdeeto1,2, Thomas R Christensen3, Timothy M Bahr4,5,6, Erick Gerday7, Mark J Sheffield7, Kyle S Christensen8, Sarayut Supapannachart1,2, Pracha Nuntnarumit1,2, Saranya Sukwiset1,2, Robin K Ohls9, Robert D Christensen9,10. 1. Ramathibodi Hospital and Chakari Nareubodindra Institute, Bangkok, Thailand. 2. Division of Neonatology, Department of Pediatrics, Mahidol University, Bangkok, Thailand. 3. University of Utah, Salt Lake City, UT, USA. 4. Department of Neonatology, Intermountain Healthcare, Murray, UT, USA. tim.bahr@imail.org. 5. Division of Neonatology, Department of Pediatrics, University of Utah Health, Salt Lake City, UT, USA. tim.bahr@imail.org. 6. Women and Newborn Research, Intermountain Healthcare, Salt Lake City, UT, USA. tim.bahr@imail.org. 7. Department of Neonatology, Intermountain Healthcare, Murray, UT, USA. 8. Brigham Young University, Provo, UT, USA. 9. Division of Neonatology, Department of Pediatrics, University of Utah Health, Salt Lake City, UT, USA. 10. Women and Newborn Research, Intermountain Healthcare, Salt Lake City, UT, USA.
Abstract
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.
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.