Department of Neonatology, Nepean Hospital, Sydney Medical School Nepean, The University of Sydney, Sydney, NSW, Australia.
School of Electrical Engineering and the Charles Perkins Center, The University of Sydney, Sydney, NSW, Australia.
PLoS One. 2022 Jul 20;17(7):e0271563. doi: 10.1371/journal.pone.0271563. eCollection 2022.
It is well established that counter-regulation to hypoxia follows a hierarchical pattern, with brain-sparing in preference to peripheral tissues. In contrast, it is unknown if the same hierarchical sequence applies to recovery from hypoxia after correction of anemia with packed red blood cell transfusion (PRBCT).
To understand the chronology of cerebral and splanchnic tissue oxygenation resulting after correction of anemia by PRBCT in preterm infants using near-infrared spectroscopy (NIRS).
Prospective cohort study.
Neonatal intensive care.
Haemodynamically stable infants: <32 weeks gestation, <37weeks postmenstrual age, <1500 grams birth weight; and ≥120 mL/kg/day feeds tolerated.
PRBCT at 15 mL/Kg over 4 hours.
Transfusion-associated changes were determined by comparing the 4-hour mean pre-transfusion cerebral and splanchnic fractional tissue oxygen extraction (FTOEc0; FTOEs0) with hourly means during (FTOEc1-4; FTOEs1-4) and for 24 hours after PRBCT completion (FTOEc5-28; FTOEs5-28).
Of 30 enrolled infants, 14[46.7%] male; median[IQR] birth weight, 923[655-1064]g; gestation, 26.4[25.5-28.1]weeks; enrolment weight, 1549[1113-1882]g; and postmenstrual age, 33.6[32.4-35]weeks, 1 infant was excluded because of corrupted NIRS data. FTOEc significantly decreased during and for 24 hours after PRBCT (p < 0.001), indicating prompt improvement in cerebral oxygenation. In contrast, FTOEs showed no significant changes during and after PRBCT (p>0.05), indicating failure of improvement in splanchnic oxygenation.
Improvement in regional oxygenation after PRBCT follows the same hierarchical pattern with a prompt improvement of cerebral but not splanchnic tissue oxygenation. We hypothesise that this hierarchical recovery may indicate continued splanchnic hypoxia in the immediate post-transfusion period and vulnerability to transfusion-associated necrotizing enterocolitis (TANEC). Our study provides a possible mechanistic underpinning for TANEC and warrants future randomised controlled studies to stratify its prevention.
众所周知，缺氧的代偿遵循一个分层模式，优先保护脑部而不是外周组织。相比之下，目前尚不清楚在纠正贫血后通过输注浓缩红细胞（PRBCT）恢复缺氧时是否存在相同的分层顺序。
使用近红外光谱（NIRS）了解通过 PRBCT 纠正早产儿贫血后脑和内脏组织氧合的时间顺序。
前瞻性队列研究。
新生儿重症监护病房。
血流动力学稳定的婴儿：<32 周妊娠，<37 周孕龄，<1500 克出生体重；并耐受≥120 毫升/千克/天的喂养。
PRBCT 剂量为 15 毫升/千克，输注时间为 4 小时。
通过比较 4 小时平均预输血脑和内脏组织氧摄取分数（FTOEc0；FTOEs0）与输注期间每小时平均值（FTOEc1-4；FTOEs1-4）以及 PRBCT 完成后 24 小时（FTOEc5-28；FTOEs5-28）来确定输血相关变化。
在纳入的 30 名婴儿中，有 14 名（46.7%）为男性；中位（IQR）出生体重为 923[655-1064]g；胎龄为 26.4[25.5-28.1]周；入组时体重为 1549[1113-1882]g；和校正后胎龄为 33.6[32.4-35]周，有 1 名婴儿因 NIRS 数据损坏而被排除。FTOEc 在 PRBCT 期间和之后 24 小时内显著降低（p<0.001），表明脑氧合迅速改善。相比之下，FTOEs 在 PRBCT 期间和之后没有显著变化（p>0.05），表明内脏氧合没有改善。
PRBCT 后区域性氧合的改善遵循相同的分层模式，脑组织氧合迅速改善，但内脏组织氧合没有改善。我们假设这种分层恢复可能表明在输血后即刻仍存在内脏缺氧和易发生输血相关坏死性小肠结肠炎（TANEC）。我们的研究为 TANEC 提供了一个可能的机制基础，并需要未来的随机对照研究来分层预防。
