A nurse's guide to early detection of umbilical venous catheter complications in infants

Umbilical Vein Calcification Associated with Double-Lumen Catheter Malpositioning in an Extremely Low-Birth-Weight Infant

Umbilical venous (UV) catheters (UVCs) are commonly used in severely ill neonates. Complications associated with UVC often result from an inappropriate UVC position. Calcification of the UV, a rare complication, was observed in an extremely low-birth-weight infant born at 23 weeks of gestation. After birth, the infant experienced respiratory and circulatory dysfunction, followed by disseminated intravascular coagulation (DIC). A UVC was inserted, and circulatory agonists and blood transfusions were administered, as well as a calcium gluconate infusion for hypocalcemia and hyperkalemia. Ten days after birth, calcification was detected in the UV, likely due to a tunica intima injury caused by UVC, a hypercoagulable state due to DIC, and a high-dose calcium gluconate infusion. Additionally, proximal port malpositioning of the double-lumen catheter might have contributed to calcification within the UV. To prevent such complications, real-time ultrasound confirmation with agitated saline contrast during UVC placement is recommended; in the absence of the facility or skills for ultrasonography, X-rays should be performed in the lateral and anteroposterior views. Furthermore, when using multi-lumen catheters, physicians should not only verify the tip position but also ensure proper placement of proximal ports and carefully select medications administered through the ports.

Inadvertent Migration of Umbilical Venous Catheters Often Leads to Malposition

BACKGROUND

Migration of umbilical venous catheters (UVCs) has been described anecdotally.

OBJECTIVES

The aim of this paper was to investigate migration of UVCs using ultrasonography (US).

METHODS

In a prospective observational study, the position of UVCs was determined using serial US within 24 h, at midweek, and at the end of the week after umbilical catheterization. Migration was recorded in distance and direction. Malposition was defined as a position of the UVC in the heart (right atrium or more distal along the UVC-route), umbilicoportal confluence, or in the umbilical vein. UVC position determined by US was compared with chest X-rays (CXRs) when these were performed for standard care within the same period of 1 h.

RESULTS

Migration of UVCs was detected with US in 25/40 infants (63%) in 32 occasions, leading to malposition in 17/25 (68%) infants. UVCs migrated inwards in 18/32 (56%), leading to a position within the heart in 17/18 occasions. Most migrations occurred before Day 3 (21/32 [66%]). When a CXR was taken at the same time as US was performed (30 occasions), the assessment of the catheter-tip position differed in 23% of the occasions. When malposition was detected by US, this was detected on routinely performed CXRs in 11% of the occasions.

CONCLUSIONS

UVCs often migrate following insertion, often leading to malposition. Awareness for this is needed, and US is a feasible alternative for detecting malposition compared to CXRs and avoids additional radiation. Re-evaluation of the position of UVCs at least once, but within 24 h after placement, is recommended.

Comparison of Wright's formula and the Dunn method for measuring the umbilical arterial catheter insertion length

BACKGROUND

Umbilical artery catheterization is the standard procedure for arterial access in neonatal intensive care units. An umbilical arterial catheter (UAC) needs to be placed accurately during the initial insertion because malpositioning increases catheter-related complications and subsequent repositioning exposes newborns to unnecessary handling, further radiologic exposure, and an increased risk of infection. To measure the UAC insertion length in newborns, we compared the conventional practice (i.e., the Dunn method) with a new formula: Wright's formula.

METHODS

The study enrolled 119 newborns. A nomogram derived from Dunn was used during the first study period and the new formula devised by Wright (4 × birth weight + 7 cm) was used during the second study period. The catheter tip position on the initial radiograph was evaluated as correct (i.e., T6-T10), overinsertion (i.e., <T6), or underinsertion (i.e., >T10).

RESULTS

The demographic profiles were not different between the two groups, which included sex; birth weight; and the number of preterm births, low-birth-weight (LBW) newborns, and very-low-birth-weight (VLBW) newborns. When using Wright's formula and the Dunn method, 83% of newborns and 61% of newborns, respectively, received a correct insertion (p < 0.05). The success rate for positioning the UAC tip between T7 and T8 was approximately two-fold higher when using Wright's formula than when using the Dunn method. In particular, the rate of correct insertion was significantly higher with Wright's formula in term newborns, LBW newborns, VLBW newborns, and small for gestational age (SGA) newborns (p < 0.05); however, the rate of overinsertion with the Dunn method was much higher in term newborns, LBW newborns, VLBW newborns, and SGA newborns (p < 0.05).

CONCLUSION

The use of Wright's formula overall results in superior correct placement of the UAC tip. It may be a more accurate and practical method than the conventional practice for measuring the UAC insertion length in newborns.

Revised formula to determine the insertion length of umbilical vein catheters

The method of Shukla is commonly used to predict the insertion length of umbilical vein catheters (UVCs) but often leads to over-insertion. Malposition of UVCs can lead to complications. In this study, we compared the formula of Shukla, i.e., (3 x birthweight in kg + 9) / 2 + 1 cm with a revised formula, i.e., (3 x birthweight in kg + 9) / 2 cm in determining the insertion length of UVCs. A cohort where the revised formula was used for UVC placement (revised group) was compared with a historical cohort using the conventional formula (Shukla group). We evaluated the position of UVCs stated as the corresponding vertebra level with a radiograph of the infant's chest and abdomen immediately after insertion in both groups. Positioning of the catheter tip above the ninth or below the tenth thoracic vertebra was considered too high or too low, respectively. Median position of 93 UVCs placed according to Shukla was lower (seventh thoracic vertebra, interquartile range (IQR) 6-9) when compared to 92 UVCs placed according to the revised formula (eighth thoracic vertebra (IQR 7-9)). UVCs were more often over-inserted using the Shukla formula (73%) when compared to the revised formula (54%). One UVC in the Shukla group (1%) and two UVCs in the revised group (2%) were placed too low (p = NS).

CONCLUSION

The revised formula reduces the rate of over-insertion of UVCs without increasing the rate of inadequate lower positioning.

Heparin infusion to prevent umbilical venous catheter related thrombosis in neonates

OBJECTIVE

To investigate umbilical venous catheter (UVC) related thrombosis by Doppler echocardiographic evaluation of neonates infused with heparin or placebo.

METHODS

We conducted a prospective study to determine UVC-related thrombosis in term and nearterm neonates. Heparin or placebo (0.5 IU/mL) was infused at a rate of 1 mL/hr to the study and control group. Doppler echocardiography was performed at 1, 3, and 5 days after UVC insertion.

RESULTS

Forty-six neonates (63% males) with a mean gestational age of 38.2 ± 1.8 weeks, and a mean birth-weight of 2993 ± 563 grams were included. No UVC-related thrombosis was observed in the study group, which included 19 neonates. Among the 27 neonates in the control group, one neonate developed UVC-related thrombosis. There were no statistical differences between the groups for gestational age, birth weight, postnatal age, UVC duration, mortality, mechanical ventilation, and inotrope requirement, and hemagram or coagulation profile. The complications were as follows, mild pulmonary hemorrhage, 6.5% (3); leak-out, 4.3% (2); peritoneal leakage, 2.2% (1); occlusion, 2.2% (1); gastrointestinal findings, 6.5% (3); sepsis, 10.9% (5); and catheter-related thrombosis, 2.2% (1).

CONCLUSION

This study demonstrated that heparin infusion of 0.5 IU/mL through the UVC had no effect on catheter-related thrombosis in term and near-term neonates. Randomized controlled trials are necessary to conclusively evaluate the effect of heparin on UVC-related thrombosis.

Poor accuracy of methods currently used to determine umbilical catheter insertion length

This study compares the methods of Dunn and Shukla in determining the appropriate insertion length of umbilical catheters. In July 2007, we changed our policy for umbilical catheter insertions from the method of Dunn to the method of Shukla. We report our percentage of inaccurate placement of umbilical-vein catheters (UVCs) and umbilical-artery catheters (UACs) before and after the change of policy. In the Dunn-group, 41% (28/69) of UVCs were placed directly in the correct position against 24% (20/84) in the Shukla-group. The position of the catheter-tip of UVCs in the Dunn-group and the Shukla-group was too high in 57% (39/69) and 75% (63/84) of neonates, respectively. UACs in the Dunn-group were placed directly in the correct position in 63% (24/38) compared to the 87% (39/45) of cases in Shukla-group. The position of the catheter-tip of UACs in the Dunn-group and the Shukla-group was too high in 34% (13/38) and 13% (6/45) of neonates, respectively. In conclusion, the Dunn-method is more accurate than the Shukla-method in predicting the insertion length for UVCs, whereas the Shukla-method is more accurate for UACs.

Cardiac arrhythmias associated with umbilical venous catheterisation in neonates

Umbilical venous catheters (UVCs) are commonly used in the management of severely ill neonates. Several life-threatening complications have been described, including catheter-related infections, myocardial perforation, pericardial effusion and cardiac arrhythmias. This report describe two neonates with cardiac arrhythmias due to umbilical venous catheterisation. One neonate had a supraventricular tachycardia requiring treatment with intravenous adenosine administration. Another neonate had an atrial flutter and was managed successfully with synchronised cardioversion. The primary cause of cardiac arrhythmias after umbilical venous catheterisation is inappropriate position of the UVC within the heart and the first step to treat them should be to pull back or even remove the catheter. Cardiac arrhythmia is a rare but potentially severe complication of umbilical venous catheterisation in neonates.

Nurses' guide to early detection of umbilical arterial catheter complications in infants

Umbilical arterial catheters (UAC) are routinely used in the care of critically ill newborns. Complications related to UACs include vascular compromise, hemorrhage, complications related to malposition, severance of the catheter itself, and infection. This article is Part II in a series dedicated to assessing infants with an umbilical catheter. Part I focused on infants with umbilical venous catheters; this article will focus on the physical assessment relevant to infants with an UAC. Complications related to UACs can occur during any phase of treatment: insertion, while indwelling, or after discontinuing the catheter. Review of clinical signs of complications along with clinical photographs, will assist caregivers in promptly recognizing UAC-related complications.