摘要 目的：探讨出生后早期蛋白质和能量摄入对早产儿早期生长速率的影响。方法：采用回顾性研究的方法，收集出生体重小于1800 g并治愈出院的164例早产儿的临床资料，记录早产儿一般情况、肠内外营养支持及体格增长情况。按氨基酸应用起始日的不同分为24 h内应用氨基酸组（EAA组,n=112）和24 h后应用氨基酸组（LAA组，n=52），比较两组早产儿在住院期间的蛋白质和能量摄入、蛋白/能量比及体格增长速率，并对两组早产儿的蛋白质和能量摄入及蛋白/能量比与体格增长速率的关系进行相关分析。结果：EAA组的早产儿体重下降幅度比LAA组低（6.3% vs 8.8%），恢复至出生体重时间比LAA组早（7 d vs 9 d）；每周头围增长速率比 LAA组快（0.79±0.25 cm vs 0.55±0.25 cm）；每日平均体重增长速率比LAA组快（20±3 g/kg vs 17±3 g/kg)。相关分析表明，早产儿第3天及第7天的蛋白质和能量摄入及蛋白/能量比与住院期间平均体重增长速率均呈正相关。恢复出生体重后每周的蛋白质和能量摄入与每周体重增长速率呈多元线性相关（r=0.709，P<0.01）。早产儿第3天及第7天的蛋白质摄入与早产儿头围增长速率及身长增长速率呈正相关。结论：早期应用氨基酸能够降低早产儿出生早期的体重下降幅度，更早恢复至出生体重，加速住院期间的体重及头围增长速度。在适宜能量摄入相对固定的情况下，在一定范围内提高蛋白质摄入量能够增加早产儿的体重、头围及身长的增长速率。
Abstract：OBJECTIVE: To study the effect of early protein and energy intake on early growth velocity of premature infants. METHODS: Clinical data on premature infants with a birth weight of less than 1800 g were collected retrospectively, including records of general status, enteral and parenteral nutrition and growth parameters. These premature infants were divided into two groups according to the timing of amino acid administration: early supplementation (the first 24 hrs of life; EAA group; n=112) and late supplementation (after 24 hrs of life; LAA group; n=52). Protein and energy intake, protein/energy ratio and growth velocity during hospital stay were compared between the two groups. Correlation analysis was used to evaluate the association of early protein and energy intake and protein/energy ratio with growth velocity of infants. RESULTS: Compared with the LAA group, the EAA group presented lower weight loss (6.3% vs 8.8%), shorter time to return to birth weight (7 days vs 9 days), and higher head circumference growth (0.79±0.25 cm/week vs 0.55±0.25 cm/week) and weight growth velocity(20±3 g/kg?d vs 17±3 g/kg?d) (P<0.05). The correlation analysis indicated that protein and energy intake and protein/energy ratio on the 3rd and 7th days of life were positively correlated with weight growth velocity. The protein and energy intake per week after returning to birth weight was positively correlated with weight growth velocity (r= 0.709, P<0.01). Significant correlations were found between the protein and energy intake and both head circumference and length growth velocity on the 3rd and the 7th days of life. CONCLUSIONS: Early administration of amino acids can reduce weight loss, shorten the time taken to return to birth weight, and increase weight and head circumference growth velocity in premature infants. An appropriate increase in protein intake can improve weight, circumference and length growth velocity.
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