Umbilical arterial catheter insertion length: in quest of a universal formula

Abstract

Objective: The study was aimed at comparing the accuracy in length of insertion of umbilical arterial catheter in all new born groups stratified according to weight, by using two different methods, that is, Wright et al./ Case (Group I): (4 Â Body wt (BW) (kg)) þ 7; Shukla et al./Control (Group II): (3 Â BW (kg)) þ 9.Study Design: It was a randomized open label case control study in a Level III tertiary level Neonatal Intensive Care Unit over 9 months.Result: The babies in both the groups were similar in relation to weight, gender, prematurity and weight subgroups. Under insertion was seen in 8% (4/50) of babies in group I and over insertion was seen in group II where it was 32.6% (16/49). There was a reduction of 82% abnormal insertions and repositioning by using the Wright's formula as compared with the Shukla's formula in preterm babies. Statistically significant reduction in repositioning was seen in all babies <1500 g in Group I and under insertion seen in 8% of babies in group I did not attain statistical significance (P ¼ 0.34).Conclusions: There is no universal formula, which gives the accurate length of placement of an umbilical arterial catheter, but Wright's formula comes closer in neonates with different weight sub groups.

Accuracy of 11 formulae to guide umbilical arterial catheter tip placement in newborn infants

“…They found an 82% reduction in incorrect tip placement when using Wright’s formula (F7), with significant reduction in repositioning seen in all babies <1500 g 17. In our study, both formulae had similar accuracy (table 3) in infants <32 weeks.…”

“…Kumar et al compared the formulae described by Wright (F7)13 and Shukla (F5)12 in a randomised controlled trial,17 which included 99 infants, stratified by birth weight. They found an 82% reduction in incorrect tip placement when using Wright’s formula (F7), with significant reduction in repositioning seen in all babies <1500 g 17.…”

Comparison between Wright and Shukla formulas: which is better for the placement of umbilical catheters in newborns Ó� 1500 g?

“…The percentage of venous and arterial umbilical catheters correctly placed with Wright's formula was higher than Shukla's formula, both in patients < 1000 g and > 1000 g, which demonstrates the clinical superiority of this formula. The results of the present study showed no significant differences between the use of either Wright's or Shukla's formula for the correct placement of venous and arterial umbilical catheters in patients < 1500 g. Kumar et al 19 also compared these two formulas in 99 newborns stratified by birth weight and demonstrated an 82% reduction in incorrect placement of the tip of the umbilical arterial catheter when using Wright's formula, with a significant difference in catheter placement in neonates < 1500 g. There were 12 physicians involved in the insertion of catheters, verified by two independent physicians, and reviewed with a radiologist. In contrast, in the present study, catheter placement was verified at first intent by a single neonatologist and corroborated with a radiologist.…”

Optimal Line and Tube Placement in Very Preterm Neonates: An Audit of Practice

“…The high position is recommended for umbilical arterial catheters (UACs); in the aorta, it is ideally between T6 and T9 vertebral bodies [ 11 ]. Despite a number of calculations based on both birth weight and external measurements for estimating correct positioning, there is a lack of consensus in the literature as to which is the most accurate [ 2 , 9 , 12 , 13 , 14 ].…”