英国伦敦帝国理工学院、约克大学等研究机构组成的联合研究小组最新研究指出，限制较少的输血策略可能改善预后。 2019年8月1日，国际知名学术期刊《新英格兰医学杂志》发表了这一成果。

世界卫生组织(World Health Organization)建议，无并发症的严重贫血(血红蛋白水平为每分升4至6克，没有临床严重程度的迹象)而住院的非洲儿童不要输血。然而，高死亡率和再入院率表明，限制较少的输血策略可能改善预后。

在这项析因、非盲、随机、对照试验中,该研究组将乌干达和马拉维2个月到12岁的患有无并发症严重贫血的儿童随机分为立即输血（每公斤体重20毫升或30毫升），同时随机化地确定没有立即输血组(对照组),其中，当临床严重程度的新迹象或血红蛋白降至每分升4克以下时，每公斤20毫升全血当量的输血。初步的结果是28天的死亡率。 另外三组随机研究了输血量、出院后补充微量营养素和出院后预防使用甲氧苄啶-磺胺甲恶唑。 随机抽取1565名儿童(中位年龄26个月)，其中立即输血组778名，对照组787名;984名儿童(62.9%)患有疟疾。 随访180天，其中71例(4.5%)失访。在初次住院期间，立即输血组所有患儿均进行输血，对照组386例(49.0%)患儿进行输血(中位输血时间为1.3小时，随机化后为24.9小时)。 即刻输血组患儿平均每次血容量(±SD)为314±228 ml，对照组为142±224 ml。 立即输血组7名儿童(0.9%)死亡，对照组13名(1.7%)死亡(危险比0.54;95%置信区间[CI]， 0.22 ~ 1.36;P=0.19)，到第180天分别为35天(4.5%)和47天(6.0%)(危险比为0.75;95% CI, 0.48 ~ 1.15)，没有与其他随机化相互作用的证据(P > 0.20)，也没有再入院、严重不良事件或180天血红蛋白恢复的组间差异的证据。 对照组平均住院时间延长0.9天。在6个月的临床结果中，接受立即输血的儿童和没有接受输血的儿童之间没有任何差异。 对照组采用触发式输血策略，导致血流量降低;然而，住院时间更长，这一策略需要临床和血红蛋白监测。

附：英文原文

Title: Immediate Transfusion in African Children with Uncomplicated Severe Anemia

Author: Kathryn Maitland, M.D., Ph.D., Sarah Kiguli, M.B., Ch.B., M.Med., Peter Olupot-Olupot, M.B., Ch.B., Ph.D., Charles Engoru, M.B., Ch.B., Macpherson Mallewa, M.R.C.P.C.H., Ph.D., Pedro Saramago Goncalves, Ph.D., Robert O. Opoka, M.Med., Ayub Mpoya, M.Sc., Florence Alaroker, M.B., Ch.B., M.Med., Julius Nteziyaremye, M.B., Ch.B., George Chagaluka, M.D., M.R.C.P.C.H., Neil Kennedy, M.D., M.R.C.P.C.H., et al., for the TRACT Group*

Issue&Volume: Vol.381 No.5, 2019

Abstract: 

        BACKGROUND

The World Health Organization recommends not performing transfusions in African children hospitalized for uncomplicated severe anemia (hemoglobin level of 4 to 6 g per deciliter and no signs of clinical severity). However, high mortality and readmission rates suggest that less restrictive transfusion strategies might improve outcomes.

METHODS

In this factorial, open-label, randomized, controlled trial, we assigned Ugandan and Malawian children 2 months to 12 years of age with uncomplicated severe anemia to immediate transfusion with 20 ml or 30 ml of whole-blood equivalent per kilogram of body weight, as determined in a second simultaneous randomization, or no immediate transfusion (control group), in which transfusion with 20 ml of whole-blood equivalent per kilogram was triggered by new signs of clinical severity or a drop in hemoglobin to below 4 g per deciliter. The primary outcome was 28-day mortality. Three other randomizations investigated transfusion volume, postdischarge supplementation with micronutrients, and postdischarge prophylaxis with trimethoprim–sulfamethoxazole.

RESULTS

A total of 1565 children (median age, 26 months) underwent randomization, with 778 assigned to the immediate-transfusion group and 787 to the control group; 984 children (62.9%) had malaria. The children were followed for 180 days, and 71 (4.5%) were lost to follow-up. During the primary hospitalization, transfusion was performed in all the children in the immediate-transfusion group and in 386 (49.0%) in the control group (median time to transfusion, 1.3 hours vs. 24.9 hours after randomization). The mean (±SD) total blood volume transfused per child was 314±228 ml in the immediate-transfusion group and 142±224 ml in the control group. Death had occurred by 28 days in 7 children (0.9%) in the immediate-transfusion group and in 13 (1.7%) in the control group (hazard ratio, 0.54; 95% confidence interval [CI], 0.22 to 1.36; P=0.19) and by 180 days in 35 (4.5%) and 47 (6.0%), respectively (hazard ratio, 0.75; 95% CI, 0.48 to 1.15), without evidence of interaction with other randomizations (P>0.20) or evidence of between-group differences in readmissions, serious adverse events, or hemoglobin recovery at 180 days. The mean length of hospital stay was 0.9 days longer in the control group.

CONCLUSIONS

There was no evidence of differences in clinical outcomes over 6 months between the children who received immediate transfusion and those who did not. The triggered-transfusion strategy in the control group resulted in lower blood use; however, the length of hospital stay was longer, and this strategy required clinical and hemoglobin monitoring. (Funded by the Medical Research Council and Department for International Development; TRACT Current Controlled Trials number,ISRCTN84086586opens in new tab.)

DOI: 10.1056/NEJMoa1900105

Source: https://www.nejm.org/doi/full/10.1056/NEJMoa1900105