To analyze the correlation between peripherally inserted central catheter(PICC) standardized catheterization length and body parameters in low birth weight infants(LBWI),and to construct a predictive formula for PICC standardized catheter placement length.

A total of 175 LBWIs who received PICC in the right upper limb or right lower limb in the neonatal intensive care unit of Shanxi Bethune Hospital were selected as research subjects from January 2023 to December 2024.General demographic data(gender,postnatal age at catheterization) and catheterization data[catheterization vein,arm circumference(for upper limb),calf circumference(for lower limb),body weight at catheterization,standardized catheter placement length] were collected.Pearson correlation analysis was used to explore the correlation between variables and standardized catheter placement length for each vein.Based on simple linear regression analysis results,predictive formulas for PICC standardized catheter placement length in different veins for LBWIs were constructed.Bland-Altman plots were used to analyze the agreement between predicted and actual insertion lengths for each vein.

Standardized catheter placement lengths for the right basilic vein,right median cubital vein,right cephalic vein,and right great saphenous vein were all positively correlated with arm circumference,calf circumference and body weight at catheterization(all P<0.05).Standardized catheter placement lengths for the right basilic vein and right great saphenous vein were also positively correlated with postnatal age at catheterization(both P<0.05).Among all parameters,body weight at catheterization showed the highest correlation with standardized catheter placement length for all four veins.Based on simple linear regression analysis,four prediction equations were constructed to predict the standardized catheterization length. Standardized catheter placement length for right basilic vein=6.941+2.562×body weight at catheterization(kg).Standardized catheter placement length for right median cubital vein=8.110+2.153×body weight at catheterization(kg).Standardized catheter placement length for right cephalic vein=7.583+2.539×body weight at catheterization(kg).Standardized catheter placement length for right great saphenous vein=16.574+3.953×body weight at catheterization(kg).Bland-Altman plots showed that the mean differences between predicted and actual insertion lengths were small for all four veins,with almost all data points falling within the 95% confidence interval.

PICC standardized catheter placement length in LBWIs is positively correlated with body weight at catheterization.The prediction formulas based on body weight at catheterization demonstrate high accuracy.