SMJ v1 51-58 Sujitra

1Division of Neonatology, Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, 2Department of

Pediatrics, Samutsakhon Hospital, Samutsakhon, Thailand, 3Department of Pediatrics Nursing, Faculty of Nursing, Mahidol University, Bangkok, Thailand.

All material is licensed under terms of the Creative Commons Attribution 4.0 International (CC-BY-NC-ND 4.0) license unless otherwise stated.

ABSTRACT

Objective: To compare the rate of catheter dislodgement between the bridging technique and contactless technique (CLT) for umbilical catheter securement in preterm infants.

Materials and Methods: This pilot randomized controlled trial enrolled 30 preterm infants who were randomized in a 1:1 ratio into either the bridging or CLT group. The primary outcome was catheter dislodgement. Secondary outcomes included skin injury, procedural duration, and complications such as omphalitis, catheter-related bloodstream infection (CRBSI), and hypothermia.

Results: A total of 15 patients were included in each group. In the CLT group, 25 catheters were placed (12 umbilical arterial catheters (UAC) and 13 umbilical venous catheters (UVC)), while 24 catheters were placed in the bridging group (10 UACs and 14 UVCs). There was no significant difference in catheter dislodgement rates (1 in 25 catheters in the CLT group vs 0 in 24 catheters in the bridging group, p = 1.00). There was no CRBSI in either group. Skin injuries were minimal, with one case in the bridging group and none in the CLT group (p = 1.00). Repositioning challenges were observed with the CLT after the umbilical stump had dried.

Conclusion: The CLT method demonstrated comparable catheter stability to the bridging technique and may reduce skin injury. It is cost-effective and simple to apply. However, its effectiveness in extremely preterm infants requires further investigation.

Keywords: Umbilical catheterization; securement; preterm infants; skin injury (Siriraj Med J 2026;78(1):51-58)

Umbilical catheterization is a common and essential procedure in neonatal intensive care units (NICUs), particularly for managing critically ill or preterm neonates who require reliable vascular access for fluid resuscitation, medications, and blood sampling.1 Various securement techniques have been described, with significant variability in clinical practice depending on institutional preferences, staff experience, and patient characteristics.2-6 One widely used method is the bridging technique, in which adhesive tape is applied to the catheter and affixed to the infant’s skin to create a stabilizing bridge. However, this approach has the potential for skin injury due to the adhesive tape especially in very preterm infants.4,7 Skin injuries, including erythema, epidermal stripping, and medical adhesive-related skin injury, are particularly common in infants less than 32 weeks’ gestation and can result in discomfort, infection risk, and delayed healing.7,8 An alternative approach is the anchoring technique, described by South and Magnay3, which avoids direct adhesive contact with the infant’s skin. In this method, a purse-string suture is placed around the umbilical stump, and the suture tail is passed through zinc oxide tape wrapping around the catheter and tied securely. This technique has shown favorable outcomes, including the absence of skin injuries and only a few instances of catheter dislodgement, highlighting its potential advantages in minimizing adhesive-related complications.2,5 A recent study by D’Andrea et al. found that adding cyanoacrylate glue to suturing reduced catheter dislodgement within

48 hours (1.5% vs. 23.1%, p<0.01), although this benefit diminished thereafter.9 However, cyanoacrylate glue may not be available in all centers and can increase procedural costs.

Despite the variety of securement strategies described in the literature, our unit developed a contactless technique (CLT) by modifying the anchoring technique: the umbilical catheter is sutured at the base of the stump and secured onto a transparent dressing (Tegaderm™) rather than directly to the skin. This method avoids adhesive contact and may reduce the risk of skin injury, particularly in very preterm infants with fragile skin. To evaluate this technique, we conducted a pilot randomized controlled trial comparing it with the conventional bridging method. The primary objective was to assess catheter dislodgement rates. Secondary objectives included the incidence of skin injury, procedural duration, and complications following the procedure.

Study design and population

This study was a single-center, pilot randomized controlled trial conducted in the NICU at Siriraj Hospital, Mahidol University, between 27 May 2024 and 29 Dec 2024. Eligible participants were infants born at a gestational age of less than 37 weeks who required umbilical catheterization for clinical indications, with an anticipated catheter dwell time of at least 24 hours. Infants were excluded if catheter placement was unsuccessful. Enrolled infants were withdrawn if catheter malposition was identified,

if the catheter was not used, or if it was removed within 24 hours of placement. After enrollment, infants were randomized in a 1:1 ratio using a computer-generated randomization sequence with variable block sizes of 2 and

4. Allocation was concealed using sequentially numbered, opaque sealed envelopes. The study was approved by the Siriraj Institutional Review Board (Si 300/2024, 12 Apr 2024) and registered with the Thai Clinical Trials Registry (TCTR no. 20240522005, 22 May 2024).

Study procedure

Prior to patient enrollment, neonatal fellows practiced CLT using mannequins for one month to ensure procedural consistency. Umbilical catheterization was performed by a pediatric resident or neonatal fellow under the supervision of a neonatal fellow or attending neonatologist. Catheter size was selected based on the infant’s birth weight. Infants weighing less than 1,500 grams received a 3.5 Fr catheter for arterial and venous access. Infants weighing 1,500 grams and above received a 3.5 Fr catheter for arterial access and 5 Fr catheter for venous access. The insertion

depth was calculated using Shukla’s birth weight-based formula for each catheter type.10 Following successful catheter placement, the securement method was assigned by opening a sequentially numbered, sealed opaque envelope. For all infants, initial catheter stabilization was achieved using a 3-0 silk suture tied around the catheter at the base of the umbilical stump with two to three knots to ensure secure anchoring. This step was performed consistently prior to applying the assigned securement technique. In the CLT group (Fig 1), a Tegaderm™ was used to affix the anchoring suture knot and the suture tail to the catheter. An additional suture was passed through the Wharton’s jelly of the umbilical stump and tied to the dressing, providing added stability without the use of adhesive tape on the skin. In bridging technique group (Fig 2), the catheter was first stabilized with Micropore™ tape. A transparent film dressing (Tegaderm™) was placed over the infant’s abdominal skin prior to final taping, so that the Micropore™ tape did not make direct contact with the skin. This was intended to reduce the risk of skin injury during tape removal.

Fig 1. Contactless technique for umbilical catheter securement in a real patient (left panel) and a model (right panel).

Radiographic imaging was performed immediately after catheter securement to confirm tip position and was repeated as necessary to ensure continuously proper placement. The proper position of umbilical venous catheter (UVC) was defined as the tip located at the level of the T9-T10 vertebrae on chest X-ray11, while the optimal position for the umbilical arterial catheter (UAC) was between T6-T10 vertebrae.12 If malposition was detected, the catheter was repositioned accordingly.

Outcome measurements

Baseline characteristics of the enrolled infants were recorded at the time of enrollment. The primary outcome was the rate of catheter dislodgement, defined as displacement of the catheter by more than 0.5 cm from its originally secured position at the umbilical stump. This was assessed through daily visual inspection and documentation by bedside nurses. Secondary outcomes included total procedural duration, incidence of skin injury, omphalitis, catheter-related bloodstream infection (CRBSI), and changes in the infant’s body temperature before and after the procedure. Skin injuries were classified based on criteria adapted from McNichol et al.13, which describe various levels of skin damage associated with adhesive use and tape removal. These included:

Statistical analysis

Data were analyzed using IBM SPSS Statistics version 22 (IBM Corp., Armonk, NY, USA). Continuous variables were summarized as mean ± standard deviation (SD) for normally distributed data, or as median and interquartile range (IQR) for non-normally distributed data. Categorical variables were presented as frequencies and percentages. Between-group comparisons of outcomes that are continuous variables were performed using the student’s t-test as they are normally distributed. Categorical variables, including rates of catheter dislodgement, skin injury and infection, were compared using the chi-square test or Fisher’s exact test, as appropriate. A p-value <

a pilot study, the sample size was pragmatically set at 30 subjects without a formal power calculation.

A total of 68 preterm infants were assessed for eligibility. Thirty-eight patients were excluded, mostly because parents were not present to give informed consent. Thirty infants were enrolled in the study (Fig 3). Fifteen infants were allocated to the CLT group with 13 UVCs and 12 UACs placed, while the remaining 15 were assigned to the bridging group, with 14 UVCs and 10 UACs placed. Baseline demographic data are presented in Table 1. The mean gestational age was 30.2 ± 2.9 weeks in the CLT group and 30.9 ± 3.2 weeks in the bridging group (p = 0.52). Mean birth weight was 1,323 ± 428 g and 1,416

± 580 g in the CLT and bridging groups, respectively (p= 0.58). Operator experience also did not differ between groups (p = 0.22). Forty-nine umbilical catheters were placed: 25 in the CLT group (13 UVCs and 12 UACs) and 24 in the bridging group (14 UVCs and 10 UACs), as shown in Table 2. The average duration of catheter placement ranged from 4.7 to 5.6 days across catheter types and groups.

One case of catheter dislodgement occurred in the CLT group (1 of 25 catheters, 4.0%), while no dislodgements occurred in the bridging group (0 of 24 catheters). This difference was not statistically significant (p = 1.00). The dislodged catheter was a UVC that migrated into the right atrium on day 3 due to umbilical stump shrinkage. Although the catheter appeared externally secure, internal displacement required repositioning. Due to umbilical stump dryness, re-suturing was not feasible, and the catheter was re-affixed to the prior suture tail using Tegaderm™. An additional suture through the Wharton’s jelly (as described in materials and methods section) could not be placed due to umbilical stump dryness. The UVC was later dislodged during patient transfer.

Detailed procedural times and complications are shown in Table 3. The CLT group had longer mean suture time than the bridging group (10.9 ± 5.0 min vs 7.7 ± 4.2 min, p = 0.08), but a shorter total procedure time (28.5

± 13.8 min vs 38.5 ± 14.5 min, p = 0.06), though these differences were not statistically significant. Bridging-specific taping added an average of 4.9 ± 1.9 minutes to the procedure. One infant (6.7%) in the bridging group developed a mild skin injury—localized erythema at the catheter site—while no skin injuries occurred in the CLT group (p= 1.00). The skin injury resolved spontaneously without intervention. All infants in the CLT group maintained normothermia (36.5–37.5°C) throughout the procedure. In the bridging group, one

Abbreviations: CLT, contactless technique; UAC, umbilical arterial catheter; UVC, umbilical venous catheter

Catheter placement data Contactless (n=15) Bridging (n=15)

Catheter duration (days) 4.8 ± 2.1 4.7 ± 2.0 5.6 ± 1.9 4.7 ± 2.0

Abbreviations: UAC, umbilical arterial catheter; UVC, umbilical venous catheter

Abbreviations: CI, confidence interval; CRBSI, catheter-related bloodstream infection; T, temperature

infant experienced mild hypothermia (temperature drop from 36.5°C to 36.0°C) and one developed low-grade hyperthermia (>37.5°C). Mean temperature change was

−0.1 ± 0.3°C in the CLT group versus 0 ± 0.3°C in the bridging group (p = 0.17). No omphalitis or catheter-related bloodstream infection (CRBSI) occurred in either group.

This pilot randomized controlled trial evaluated a contactless technique for umbilical catheter securement against the conventional bridging method in preterm infants. Both approaches demonstrate comparable safety and efficacy with respect to catheter dislodgement, skin complications and procedural duration. In our cohort, only one catheter dislodgement occurred in the CLT group, compared to none in the bridging group; a difference that was not statistically significant. Compared to emerging securement techniques, such as cyanoacrylate glue, the CLT offers a favorable profile. D’Andrea et al. reported a 7.7% dislodgement rate using glue combined with sutures, with greater benefit during the first 48 hours of catheter use.9 Similarly, the LifeBubble umbilical catheter securement device demonstrated superior performance in reducing catheter migration and malposition14, but required a specialized device and may not be cost-effective for widespread use, especially in resource-limited settings. Another advantage of the CLT is procedural simplicity and low cost. The method uses materials commonly available in neonatal units, with a total securing time comparable to the bridging technique (10.9 ± 5.0 vs 12.7

In adults, prolonged use of strong adhesive tape is associated with skin complications such as increased rates of phlebitis.15 This highlights the potential risks that the adhesive tape pose, which are even more concerning in preterm infants whose fragile skin, is highly susceptible to medical adhesive-related skin injury.7 In our study, no skin injury was observed in the CLT group, supporting its potential as a securement method that is safe for the skin.

An important caution of the CLT method is the difficulty in readjusting catheter position and resecuring the catheter after several days, because the umbilical stump has shrunk and dried. This precludes re-suturing through the umbilical stump. As described above in the patient who had catheter dislodgement, we recommend against performing the CLT method on the dried umbilical stump as it probably increases the risk of catheter dislodgement. In this situation, bridging technique should be performed instead. Additionally, to avoid the need for catheter

repositioning, verifying catheter tip position in real time (such as with ultrasound) before securement may be beneficial, as ultrasound has been shown to improve placement accuracy in infants.16,17

There are some limitations in this study. Small sample size may limit the ability to detect differences in outcomes (both umbilical catheter securement and CRBSI). The single-center design may limit generalizability, and the short follow-up period may not capture late-onset complications or long-term securement effectiveness.

The CLT demonstrated comparable catheter stability to the bridging technique and posed no risk for skin injury. It is easy to implement and may be especially advantageous for extremely preterm infants vulnerable to skin injury. Further larger studies with longer follow-up and additional survival analysis are warranted to confirm these findings.

Data Availability Statement

The research data in this study are available from the corresponding author upon reasonable request.

The authors thank neonatal fellows for patient recruitment and procedure performance, and NICU nurses for their support in data recording. We thank Assoc. Prof. Buranee Yangthara for her help with statistical analysis. We thank Ms. Juthatip Suwannatrai for the support in patient coordination and data collection.

Grants and Funding Information

Conflict of Interest

Registration Number of Clinical Trial

Authors Contributions

Conceptualization, ST, PW and WB; Data curation, ST and WB; Formal analysis, ST, PW and WB; Investigation, ST, CS and WB; Methodology, ST, PW and WB; Project administration, ST and WB; Supervision, WB; Visualization, ST, CS and WB; Writing – original draft, ST; Writing – review & editing, PW, CS and WB. All authors have read and agreed to the final version of the manuscript.

Use of Artificial Intelligence

The authors did not use artificial intelligence in the conduct and writing of this study.

Demographic data and patient characteristics	CLT (n=15)	Bridging (n=15)	p-value
Gestational age (weeks)	30.2 ± 2.9	30.9 ± 3.2	0.52
Birth weight (grams)	1,323 ± 428	1,416 ± 580	0.58
Length (cm)	39.0 ± 4.0	39.1 ± 5.5	0.96
Male sex	7 (46.7)	4 (26.7)	0.45
Apgar score 1-minute – median (IQR) 5-minute – median (IQR)	5 (2, 8) 7 (6, 9)	7 (4, 8) 9 (7, 9)	0.84 0.39
Operator 1st year fellow 2nd year fellow	9 (60) 6 (40)	13 (86.7) 2 (13.3)	0.22
Number of catheters (UAC or UVC) (both UAC and UVC)	4 (26.7) 11 (73.3)	4 (26.7) 11 (73.3)	1

Procedure time and other secondary outcomes	Contactless (n=15)	Bridging (n=15)	Mean Difference [95%CI]	p-value
Suture time (min)	10.9 ± 5.0	7.7 ± 4.2	3.1 [-0.3, 6.6]	0.08
Bridging time (min)	-	4.9 ± 1.9	-	-
Total securing time (min)	10.9 ± 5.0	12.7 ± 5.6	-1.8 [-5.8, 2.2]	0.36
Total procedure time (min)	28.5 ± 13.8	38.5 ± 14.5	-9.9 [-20.5, 0.6]	0.06
T before procedure < 36.5 °C	0 (0)	0 (0)		0.48
36.5 - 37.5 °C	15 (100)	13 (86.7)
> 37.5 °C	0 (0)	2 (13.3)
T after procedure < 36.5 °C	0 (0)	1 (6.7)		0.48
36.5 - 37.5 °C	15 (100)	13 (86.7)
> 37.5 °C	0 (0)	1 (6.7)
T change (°C)	-0.1 ± 0.3	0 ± 0.3	-0.1 [-0.4, 0.1]	0.17
Skin injury	0 (0)	1 (6.7)		1.00
Omphalitis	0 (0)	0 (0)		-
CRBSI	0 (0)	0 (0)		-

Comparison of Bridging and Contactless Technique for Umbilical Catheter Securement in Preterm Infants: A Pilot Randomized Controlled Trial

Sujitra Terdnueakao, M.D.1,2, Punnanee Wutthigate, M.D.1, Chanoknan Sriwiset, BNS3, Walaiporn Bowornkitiwong, M.D.1,*