[Effect of red blood cell transfusion on the oxygenation of mesenteric tissue in premature infants].

Objective: To investigate the effect of red blood cell transfusion on the oxygenation of mesenteric tissue in premature infants. Methods: In this prospective cohort study, preterm infants with gestational age <37 weeks who were treated with red blood cell transfusions were enrolled from June 2017 to March 2018 in Department of Neonatology, Children's Hospital of Fudan University. The infants were categorized into feeding intolerance group and feeding tolerance group according to the feeding intolerance standard. Near-infrared spectroscopy was applied to continuously monitor intestinal oxygen saturation from 2 h before red blood cell transfusion to 48 h after red blood cell transfusion. Intergroup differences of basic conditions were analyzed with t test, Mann-Whitney U test and χ(2) test. Mixed linear model was used to compare intragroup and intergroup differences in intestinal oxygen saturation over time. Results: A total of 73 cases with gestational age <37 weeks were enrolled, of whom 41 were males and 32 were females, with mean gestational age of (30±4)weeks and mean birth weight of (1 543±688)g; there were 33 cases in feeding intolerance group and 42 cases in feeding tolerance group. The average intestinal oxygen saturations at 2 h before blood transfusion, during blood transfusion, 2, 6, 12, 24, and 48 h after transfusion were 0.50±0.07, 0.52±0.07, 0.52±0.08, 0.51±0.08, 0.51±0.07, 0.51±0.08, and 0.51±0.07 respectively in feeding intolerance group and were 0.51±0.04, 0.55±0.04, 0.57±0.05, 0.57±0.04, 0.56±0.04, 0.56±0.04, and 0.56±0.05 respectively in feeding tolerance group. Compared with 2 h before transfusion, intestinal oxygen saturation were increased during transfusion in both group (feeding intolerance group t=4.992, P=0.000; feeding tolerance group t=9.615, P=0.000), however this effect lasted until 48 h after transfusion in feeding tolerance group (t=5.519, 12.409, 10.033, 9.133, 7.983, all P=0.000). Additionally, the increasement of intestinal oxygen saturation over time were lower in feeding intolerance group(F=8.876, P=0.000). Besides, the level of intestinal oxygen saturation was positively correlated with postmenstrual age (PMA)(F=4.863, P=0.031). In infants with PMA<30 weeks, particularly in feeding intolerance group, the level of intestinal oxygen saturation significantly decreased at 2 h after transfusion (t=23.063, P=0.002). Conclusions: Feeding status and PMA may play a role in development of transfusion-associated necrotizing enterocolitis. Red blood cell transfusion may increase the risk for mesenteric ischemia and is more likely to cause necrotizing enterocolitis in preterm infants with PMA <30 weeks as well as feeding intolerance. Clinical Trail: Children's Hospital of Fudan University, NCT02544100.目的： 探讨红细胞输注对早产儿肠道组织氧合的影响。 方法： 前瞻性队列研究，选取2017年6月至2018年3月复旦大学附属儿科医院新生儿科收治的出生胎龄<37周并输注红细胞治疗的早产儿，按照喂养不耐受标准分为喂养不耐受组和喂养耐受组。利用近红外光谱监测仪持续监测患儿红细胞输注前2 h、输注过程中至输注后48 h肠道组织氧饱和度（rSO(2)）变化。两组患儿基本情况的比较采用t检验、Mann-Whitney U检验和χ(2)检验，采用混合线性模型比较两组患儿肠道rSO(2)随时间变化的组内和组间差异。 结果： 共纳入符合条件的患儿73例，其中男41例、女32例，平均出生胎龄（30±4）周，平均出生体重（1 543±688）g；喂养不耐受组33例，喂养耐受组40例。喂养不耐受组输血前2 h，输血过程中，输血后2、6、12、24、48 h肠道rSO(2)平均值分别是0.50±0.07、0.52±0.07、0.52±0.08、0.51±0.08、0.51±0.07、0.51±0.08、0.51±0.07；喂养耐受组分别为0.51±0.04、0.55±0.04、0.57±0.05、0.57±0.04、0.56±0.04、0.56±0.04、0.56±0.05；与红细胞输注前2 h比较，喂养不耐受组患儿红细胞输注过程中肠道rSO(2)升高（t=4.992，P=0.000），而喂养耐受组患儿红细胞输注过程中肠道rSO(2)升高（t=9.615，P=0.000），且此作用一直持续至红细胞输注后48 h（t=5.519、12.409、10.033、9.133、7.983，P均=0.000）；喂养不耐受组患儿肠道rSO(2)随时间增加幅度较喂养耐受组患儿小（F=8.876，P=0.000）；矫正胎龄越小的患儿，肠道rSO(2)越低（F=4.863，P=0.031），尤其是喂养不耐受组矫正胎龄<30周的患儿红细胞输注后2 h肠道rSO(2)较红细胞输注前2 h明显降低（t=23.063，P=0.002）。 结论： 喂养情况和矫正胎龄可能在早产儿输血相关性坏死性小肠结肠炎的发生发展中起着一定作用，尤其是喂养不耐受矫正胎龄<30周的早产儿红细胞输注可能会增加肠道缺血的风险，更易引起早产儿坏死性小肠结肠炎。 临床试验注册： 复旦大学附属儿科医院，NCT02544100。.