Renal Oxygenation (rSO 2 ) Population Parameter Estimates in Premature Infants Routinely Monitored With Near-Infrared...

Area of Science:

• Neonatal physiology
• Medical instrumentation
• Pediatric nephrology

Background:

• Lack of established reference ranges for renal oxygenation (rSO 2 ) using near-infrared spectroscopy (NIRS) in preterm infants beyond early life.
• Limited data on population estimates of rSO 2 trends in preterm infants, hindering clinical application.

Purpose of the Study:

• To characterize the distribution of renal oxygenation (rSO 2 ) measured by NIRS in preterm infants.
• To estimate population parameters for rSO 2 during the first 14 days of life.

Main Methods:

• Prospective observation of rSO 2 trends in 37 preterm infants (<34 weeks gestation, ≤1800g birth weight) for 14 days.
• Analysis using distribution fit tests, ordinary least squares regression, and t tests.

Main Results:

• Average daily rSO 2 showed a 42% variation over 14 days, peaking in the first 3 days and stabilizing around day 7.
• Significantly lower rSO 2 slopes were observed in male infants and those ≤29 weeks gestation.

Conclusions:

• Renal rSO 2 reflects normal extrauterine transition, stabilizing around 7 days.
• Gestational age, birth weight, and gender may predict early rSO 2 patterns.
• Population estimates can help identify early-onset tissue hypoxia.