Obstetric and Neonatal Operations, Department of Neonatology, Intermountain Healthcare, Murray, UT; Division of Neonatology, Department of Pediatrics, University of Utah Health, Salt Lake City, UT.
Division of Neonatology, Department of Pediatrics, University of Utah Health, Salt Lake City, UT.
J Pediatr. 2022 Jul;246:12-18.e2. doi: 10.1016/j.jpeds.2022.04.015. Epub 2022 Apr 14.
To investigate associations between nucleated red blood cell (NRBC) count in neonates with hypoxic-ischemic encephalopathy (HIE), acute perinatal sentinel events, and neurodevelopmental outcomes and to examine the mechanism(s) causing elevated counts.
We included newborn infants with HIE treated with therapeutic hypothermia with ≥3 NRBC counts during their neonatal intensive care unit hospitalization and neurodevelopmental evaluations at a mean of 24 ± 6 months.
Ninety-five of 152 infants who met our study criteria (63%) had a normal NRBC count after birth, defined as ≤95th percentile of the upper reference interval, and the other 57 (37%) had an elevated count. Documented sentinel events during labor resulting in emergency delivery (eg, acute abruption) (n = 79) were associated with a normal NRBC count (OR, 257; 95% CI, 33-1988). Of the 152 infants evaluated, 134 (88%) survived to discharge. The odds of surviving were 3-fold greater (OR, 3.0; 95% CI, 1.1-8.3) when the first NRBC count was normal than when it was elevated. Normal counts were moderately predictive of infants without neurodevelopmental impairment at a 2-year evaluation (P < .001). NRBC half-life was longer in infants with an elevated NRBC count compared with those with a normal count (60 hours vs 39 hours; P < .01).
In infants with HIE, a normal NRBC count after birth was associated with acute intrapartum events necessitating emergent delivery. Normal counts were modestly predictive of a better prognosis. We speculate that the elevated NRBC counts at birth resulted from hypoxia that occurred earlier or chronically. Impaired clearance of NRBCs from the blood might be one mechanistic explanation for the high counts.
研究核红细胞（NRBC）计数在患有缺氧缺血性脑病（HIE）的新生儿、急性围产期前哨事件与神经发育结局之间的关系，并探讨导致计数升高的机制。
我们纳入了在新生儿重症监护病房住院期间接受治疗性低温治疗且NRBC 计数≥3 的 HIE 新生儿，并在平均 24±6 个月时进行神经发育评估。
在符合我们研究标准的 152 名婴儿中，有 95 名（63%）在出生后 NRBC 计数正常，定义为≤上参考区间的第 95 个百分位数，而其余 57 名（37%）计数升高。分娩期间导致紧急分娩的记录在案的前哨事件（如急性胎盘早剥）（n=79）与 NRBC 计数正常相关（比值比，257；95%置信区间，33-1988）。在接受评估的 152 名婴儿中，有 134 名（88%）存活至出院。当第一 NRBC 计数正常时，存活的可能性是升高时的 3 倍（比值比，3.0；95%置信区间，1.1-8.3）。NRBC 半衰期在 NRBC 计数升高的婴儿中比正常计数的婴儿长（60 小时比 39 小时；P<0.01）。
在患有 HIE 的婴儿中，出生后 NRBC 计数正常与分娩期间需要紧急分娩的急性事件相关。正常计数适度预测预后较好。我们推测，出生时 NRBC 计数升高是由于更早或慢性缺氧所致。NRBC 从血液中清除受损可能是高计数的一个机制解释。
