极低出生体重儿PICC尖端位置与体重增长的相关性分析

A correlation analysis of PICC tip position and weight gaining in very low birth weight infants

目的探讨极低出生体重儿PICC尖端位置与体重增长的相关性。方法回顾分析某三级甲等医院新生儿重症监护室中的极低出生体重儿留置PICC期间所拍摄的胸片,记录胸片上的导管尖端位置,采用椎体定位计算导管尖端位置改变。计算拍摄胸片当日和首次定位时相比的体重增长率。采用Spearman等级相关法分析胸片上导管尖端移位和体重增长之间的关系。结果共有57例极低出生体重儿和246张胸片纳入研究。首次拍摄胸片当日体重为0.60~1.46(1.06±0.25)kg;日龄中位数和四分位间距为5(3,7)d。末次胸片时间为置管后(24.0±9.1)d;体重增长率为11.8%~114.8%,中位数和四分位间距为41.5%(27.1%,65.3%);全部患儿的PICC尖端位置出现改变,中位数和四分位间距为3(1.8,3.5)个椎体,其中75%出现2个椎体以上的移位,50%有3个椎体的移位。导管尖端偏移的幅度和体重增长率相关。在体重达到40%、70%、100%的增长率时,相对应的PICC尖端出现近似2个、3个和4个椎体的移位。PICC尖端位置改变和体重增长显著相关(r=-0.7,P<0.01);但不同体表穿刺部位二者的相关性有差异。结论极低出生体重儿的PICC尖端位置受体重增长影响。结合PICC首次定位,体重增长40%、70%是导管位置追踪的关键时机。体重增长>100%应拔除或更换导管。通过易受骨骼生长和肢体动作影响部位穿刺的PICC,需提高导管定位的频次。

Objective To investigate the correlation of PICC tip position and weight gaining in very low birth weight infants. Methods We performed a retrospective study using chest X-ray films of very low birth weight infants in NICU who had PICCs inserted in a tertiary hospital. We recorded the tip positions on plain radiographs and calculated the position change,and calculated weight gaining ratio. Spearman regression model was used to analyze the relationship between tip position migration and weight gaining ratio. Results A total of 57 cases of very low birth weight infants were included,containing 246 X-ray films. On the first day of taking X-ray,weight was 0.6-1.46 （1.06±0.25） kg,the median and interquartile spacing are 5（3,7）d. The last time of taking X-ray was（24.0±9.1） d after PICC placement; weight gaining ratio was ll.8%-l14.8%,the median and interquartile spacing are 41.5% （27.1%,65.3%）. All PICCs tip position changed,75% of which migrated more than 2 vertebrae,50% of which mi- grated 3 vertebrae,and the median and interquartile spacing are 3 （1.8,3.5） vertebrae. The distances of tip migration were correlated with weight gaining ratio. With an approximate 2,3 and 4 vertebrae of PICC tip migration,the cor- responding weight gaining ratio was about 40%,70% and 100%. The correlation coefficient between PICC tip posi- tion migration and weight gaining ratio was -0.7（P〈0.01）,but there was difference in different insertion sites. Conclu- sion PICC tip position is greatly influenced by weight gaining among very low birth weight infants. By considering the initial placement position,the crucial moment to assess catheter location is at 40% and 70% weight gaining ratio. After 100% weight gaining,PICCs should be removed or replaced. PICCs can easily be affected by bone growth and limb movement,require higher frequency of catheter localization.