Wang Dan-hua
Department of Pediatrics, Peking Union Medical College Hospital, Beijing, China.
Zhonghua Er Ke Za Zhi. 2009 Jan;47(1):12-7.
Extrauterine growth restriction in preterm infants secondary to suboptimal nutrition is a major problem in neonatal intensive care units (NICUs). This study was designed to investigate the nutritional support and growth of premature infants who were discharged from 10 tertiary NICUs in different areas in China and evaluate the effects of high risk factors on their growth.
Data of 1000 premature infants (100 infants from each hospital) were retrospectively collected, the data included their gestational age, the growth parameters at birth, complications, enteral and parenteral nutritional support strategies, the growth parameters at discharge and length of hospital stay from Jan. 1, 2005 to Jun. 30, 2006. The growth parameters, including body weight, length and head circumference, were evaluated according to growth curve of newborns in China with their gestational age at birth and corrected gestational age on discharge. Growth retardation was defined as less than the 10th percentile of the expected value. The risk factors which might result in growth retardation of premature infants were assessed with logistic regression. P < 0.05 was considered as significant.
Of the 1000 premature infants enrolled in this study, the data of 974 premature infants were finally eligible. The median gestational age of the 974 premature infants was 32.6 (31.0-34.1) weeks and median birth weight was 1732.2 (1447.9-2030.3) g. Three hundred and seventy-eight premature infants were born at < 32 weeks of gestational age and the body weight of 285 premature infants was < 1500 g at birth. The median time for initial enteral feeding was 2.0 (1, 3) days of life, 77.0% of the premature infants were fed with formulas for low birth weight, and 13.6% were fed with human milk mixed with the formulas for low birth weight. For parenteral nutrition, amino acid solutions were administered in 87.3% of premature infants and median time to begin was 2.5 (2, 3) days of life, median duration of administration was 11 (6, 17) days. Lipid emulsions were supplied in 56.9% of premature infants and median time to begin was 3 (2, 5) days of life, median duration of administration was 12 (7, 18) days. During hospital stay, 74.1% of the premature infants achieved recommended diet indexes of 120 kcal/(kg.d) (including both enteral and parenteral intakes) and mean time for achieving was (16.3 +/- 9.4) days of life, 84.1% of the premature infants reached enteral feeding of 100 kcal/(kg x d) and the mean time to achieve was (17.0 +/- 9.4) days of life. The lower the gestational age of premature infants was, the longer the time for achieving these goals was. Mean loss of weight was 7.54% +/- 4.7% of birth weight and the day for regaining to birth weight was (10.92 +/- 5.10) days. The lower the gestational age at birth, the more the loss of weight, and the longer the time for regaining to birth weight. Mean growth velocity after regaining to birth weight during hospital stay was (13.4 +/- 6.0) g/(kg x d). Mean length of hospital stay was (26.4 +/- 12.9) days. Of the 696 singletons, 60.0%, 58.9% and 29.5% of the infants had growth retardation by weight, length and head circumference respectively on discharge, while the morbidity increased by 32.7%, 30.9% and 10.2%, respectively, compared with those at birth.
Morbidity of growth retardation was high among premature infants at birth by weight, length and head circumference. Such growth retardation was further worsened before discharge. Birth weight below the 10th percentile of expected value, later introduction of enteral feeding and lower growth velocity during hospital stay were risk factors for postnatal growth retardation of premature infants. More aggressive nutritional support strategy needs to be considered for improving the nutritional status and development of premature infants in China.
因营养欠佳导致的早产儿宫外生长受限是新生儿重症监护病房（NICU）中的一个主要问题。本研究旨在调查从中国不同地区的10家三级NICU出院的早产儿的营养支持及生长情况，并评估高危因素对其生长的影响。
回顾性收集1000例早产儿（每家医院100例）的数据，数据包括其胎龄、出生时的生长参数、并发症、肠内和肠外营养支持策略、出院时的生长参数以及2005年1月1日至2006年6月30日的住院时间。根据中国新生儿生长曲线，依据出生时的胎龄和出院时的矫正胎龄，对体重、身长和头围等生长参数进行评估。生长迟缓定义为低于预期值的第10百分位数。采用逻辑回归评估可能导致早产儿生长迟缓的危险因素。P<0.05被认为具有统计学意义。
本研究纳入的1000例早产儿中，最终974例早产儿的数据符合要求。974例早产儿的中位胎龄为32.6（31.0 - 34.1）周，中位出生体重为1732.2（1447.9 - 2030.3）g。378例早产儿胎龄<32周，285例早产儿出生体重<1500 g。初次肠内喂养的中位时间为出生后2.0（1，3）天，77.0%的早产儿采用低出生体重儿配方奶喂养，13.6%的早产儿采用母乳与低出生体重儿配方奶混合喂养。对于肠外营养，87.3%的早产儿使用氨基酸溶液，开始使用的中位时间为出生后2.5（2，3）天，中位使用时间为11（6，17）天。56.9%的早产儿使用脂肪乳剂，开始使用的中位时间为出生后3（2，5）天，中位使用时间为12（7，18）天。住院期间，74.1%的早产儿达到推荐饮食指标120 kcal/（kg·d）（包括肠内和肠外摄入量），达到该指标的平均时间为出生后（16.3±9.4）天，84.1%的早产儿肠内喂养量达到100 kcal/（kg·d），达到该喂养量的平均时间为出生后（17.0±9.4）天。早产儿胎龄越低，达到这些目标的时间越长。平均体重下降为出生体重的7.54%±4.7%，恢复至出生体重的天数为（10.92±5.10）天。出生时胎龄越低，体重下降越多，恢复至出生体重的时间越长。住院期间恢复至出生体重后的平均生长速度为（13.4±6.0）g/（kg·d）。平均住院时间为（26.4±12.9）天。在696例单胎婴儿中，出院时分别有60.0%、58.9%和29.5%的婴儿体重、身长和头围生长迟缓，与出生时相比，发病率分别增加了32.7%、30.9%和10.2%。
早产儿出生时体重、身长和头围生长迟缓的发病率较高。这种生长迟缓在出院前进一步恶化。出生体重低于预期值的第10百分位数、肠内喂养开始时间较晚以及住院期间生长速度较低是早产儿出生后生长迟缓的危险因素。为改善中国早产儿的营养状况和发育，需要考虑更积极的营养支持策略。
