Effect Of Delayed Umbilical Cord Clamping On Cord Blood Gas Analysis In Term Newborns

Objective To investigate the effects of early and delayed umbilical cord clamping on umbilical cord blood gas in term normal newborns.Method According to the inclusion and exclusion criteria designed by the Institute,From August 2018 to December 2019,126 neonates with full term,singleton,and cephalic firstbirth who were delivered in the obstetrics department of the Third Affiliated Hospital of Anhui Medical University were selected as the research subjects.All newborns were healthy newborns after prenatal assessment and did not require resuscitation.ccording to the umbilical cord ligation time,45 cases were divided into early umbilical cord ligation group(<30 seconds)and 81 cases in delayed umbilical cord ligation group(30-120 seconds).After the fetus is delivered,it is placed between the mother’s legs and kept warm under a towel,The midwife clamped the umbilical cord of about 10-15 cm in the middle with two vascular forceps on the side near the fetus,Immediately cut the umbilical cord and take it to the assistant for sampling,Pre-heparinized arterial blood gas needles are used to collect blood samples,The umbilical artery is collected first,and then the umbilical vein is collected and labeled.The sampling needle should be inserted parallel to the blood vessel to prevent the needle from entering the umbilical vein through the umbilical artery.The sampling process was completed within 10 seconds,the time from fetal deliveryto umbilical cord ligation was recorded,and blood gas analysis was performed within 10 minutes in chronological order.There were no significant differences in the general conditions of neonates(maternal age,maternal analgesia,parity,gestational age,weight,gender)between the two groups.The study mainly compared the following two aspects:(1)umbilical artery blood gas analysis parameters(p H,PO2,PCO2,Lac,BE,HCO3-)in the delayed umbilical cord ligation group and early umbilical cord ligation group;(2)Umbilical vein blood gas analysis parameters(p H,PO2,PCO2,Lac,BE,HCO3-)in the delayed umbilical ligation group and early umbilical ligation group Result(1)The umbilical artery PO2 and Lac values in the delayed umbilical cord ligation group were higher than those in the early umbilical cord ligation group,and the p H,BE,and HCO3-values were lower than those in the early umbilical cord ligation group(delayed umbilical cord ligation group vs.early umbilical cord ligation group: PO2 19.57 ± 6.05 mm Hg vs.15.56 ± 5.73 mm Hg;Lac 5.23 ±1.60 mmol / L vs.4.17 ± 1.51 mmol / L;p H 7.21 ± 0.06 vs.7.24 ± 0.06;BE-5.69± 2.81 mmol / L vs.-3.89 ± 2.36 mmol / L;HCO3-23.48 ± 2.47 mmol / L vs.24.74 ± 2.13 mmol / L);The differences were all P <0.05;There was no significant difference in the PCO2 value of the umbilical artery between the delayed umbilical ligation group and the early umbilical ligature group;(2)The Lac value of the umbilical vein in the delayed umbilical cord ligation group was higher than that in the early umbilical cord ligation group(4.40 ±1.52 mmol / L vs 3.62 ± 1.30 mmol / L),with a difference of P <0.05;There were no significant differences in other parameters(p H,PO2,PCO2,BE,HCO3-)in the umbilical vein blood gas analysis between the delayed umbilical ligation group and the early umbilical ligation group.Conclusion Delayed umbilical cord ligation in term infants increases the partial oxygen pressure of umbilical arterial blood gas and the lactic acid concentration of umbilical veins,and slightly increases the parameters of acidic metabolites of umbilical arteries,However,its small range of change has no adverse effect on single-term delivery of healthy term infants without pregnancy complications.