Abstract
Background:
Failure to successfully place a peripheral venous access device, also known as a peripheral intravenous catheter, impacts patient care, safety, and satisfaction. While factors like catheter size and insertion angle have been well studied, limited research has examined the influence of catheter advancement techniques on needle tip movement, a key determinant of successful placement and patient outcomes. This study measured needle tip movement during the initial advancement of the catheter off of the needle with three different techniques.
Methods:
In this prospective, within-subject crossover study at a single academic medical center, 78 clinicians each performed nine 18-gauge catheter advancements in randomized order, three per technique, into a hand phantom using one-handed self-advancement, two-handed self-advancement, and two-person advancement. Six-degree-of-freedom electromagnetic trackers (0.2 mm spatial resolution) captured needle tip kinematics and catheter advancement. Metrics measured were straight-line displacement, path length, maximum excursion, and the axial and radial components of motion for the first 1 cm of catheter advancement off of the needle.
Results:
Two-handed self-advancement yielded the lowest displacement (1.98 ± 1.14 mm), path length (3.93 ± 2.54 mm), and excursion (2.33 ± 1.21 mm). One-handed advancement produced larger displacement (2.54 ± 1.26 mm, p = 0.012), path length (9.23 ± 5.75 mm, p < 0.001), excursion (3.44 ± 1.70 mm, p = 0.002), and radial movement (0.74 ± 0.27 mm, p < 0.001 vs both other techniques). Two-person advancement matched two-handed lateral control but showed greater axial motion (1.65 ± 1.39 mm vs 0.78 ± 1.71 mm, p = 0.001) and slightly higher displacement (2.15 ± 1.17 mm). Participants perceived the highest ease of use and effectiveness was two-handed self-advancement.
Conclusions:
Two-handed self-advancement minimized unintended needle tip motion during initial catheter advancement off of the needle suggesting prioritization in training curricula. Reducing needle tip motion may lower endothelial injury and intravenous catheter advancement failure, supporting the need for clinical technique studies.
Keywords
Introduction
Peripheral intravenous catheterization is a cornerstone of modern medical practice, with an estimated 150 million catheters placed annually in the United States and approximately 2 billion globally.1,2 Despite this ubiquity, peripheral venous access device (PVAD; also known as peripheral intravenous catheter) failure rates remain high. Studies report that 35%–50% of placed catheters have to be replaced before the completion of intended therapy, with some analyses indicating replacement rates as high as 90% in certain contexts.1,2 One study documented that an average of 1.7 catheters per patient were placed over a 3.5-day period, which was primarily attributed to catheter failure. 1 Consequently, the functional dwell time of PVADs frequently falls significantly short of the traditionally recommended 72- to 96-h replacement interval, with some citing average dwell times as low as 44 h. 1
The primary drivers of PVAD failure are phlebitis, infiltration/extravasation, catheter occlusion, and dislodgement (Table 1).1,3–7 These adverse events impact patient safety and satisfaction through pain, venous depletion, and potential delays in therapy.1,2 Many of these common complications have a significant, underappreciated biomechanical etiology related to the interaction between the needle, catheter, and the vein wall, including during the insertion process itself. 1
ED: emergency department; PVAD: peripheral venous access device.
Extensive research has sought to optimize PVAD insertion outcomes by examining variables such as needle design, insertion site and angle, patient-related factors, the use of ultrasound guidance, and catheter materials.10,12–16 Despite this breadth of investigation, a critical and dynamic phase of the procedure remains conspicuously underinvestigated: the biomechanics of advancing the flexible catheter off its semirigid introducer needle once vein access is confirmed. Specifically, the extent to which different operator techniques for catheter advancement influence displacement and angulation of the indwelling needle tip within the vein lumen during the initial catheter advancement off the “stabilized” needle into the vein remains unclear. 14
This research examines the influence of three distinct catheter advancement techniques on introducer needle tip movement during the first centimeter of IV catheter advancement off its needle. Understanding these mechanics is paramount, as less controlled needle tip motion could be a direct precursor to endothelial injury and catheter advancement failure or catheter dwell complications. The primary objective was to quantify how needle tip movement is affected by the specific catheter advancement technique during the initial 1 cm advancement of the catheter off the needle.
Methods
This prospective, within-subject crossover study conducted at the University of Florida Shands Hospital between September 2024 and May 2025, received approval from the University of Florida’s Institutional Review Board (UFIRB #02400590). An a priori power analysis for the within-subject comparisons indicated a required sample of ≈50 participants (medium effect). The study included a total of 78 participants, exceeding this target. Consenting participants were enrolled if they were at least 18 years old and if they had placed peripheral intravenous (IV) catheters in the course of their work or training. Participants were excluded if they did not have at least 1 year of clinical experience. This was a clinician-only simulation study; no patients were involved, and no adverse events occurred.
Simulator and experimental protocol
A hand phantom consisting of a ballistics gel block (Gelatin #5, Humimic Medical) molded into a dorsal hand with lifted veins and covered with fabric (80% nylon, 20% spandex, Matte Milliskin Tricot, Black, Fabric Wholesale Direct) simulated skin and subcutaneous resistance (Figure 1). An 18-gauge (Ga) PVAD (B. Braun Introcan Safety, Melsungen, Germany, 18-Ga × 1¾″) was fitted to be tracked at the needle tip and on the catheter with a trakSTAR electromagnetic sensor (Ascension Technology Corporation/NDI, Milton, VT, USA; 0.2 mm spatial, 0.5° angular resolution), which recorded six-degree-of-freedom needle tip and catheter information. 17
Instrumented peripheral intravenous catheterization simulator and data capture software.
Each participant performed nine trials, which consisted of three insertions in randomized order generated by Random.org for each of the following techniques: one-handed operator self-advancement (one-handed), two-handed operator self-advancement (two-handed), and catheter advancement by another individual while the needle-inserting operator stabilized the needle (two-person). Blinding was not feasible because participants were instructed which technique to perform in each trial; outcomes were automatically recorded by sensors and analyzed from deidentified datasets. Study subjects were recruited in pairs, with partners assisting each other with the two-person technique. Prior to performing the catheter advancements, each subject was familiarized with the simulator. The participant would insert the needle into the gel such that its tip and the catheter tip were inside the gel. Once the subject indicated readiness to advance the catheter, a member of the research team started data collection via the simulator software and verbally indicated to the participant to commence their catheter advancement. Data for each trial were recorded from the start of data collection until 1 cm of catheter advancement. A new catheter was placed on the instrumented needle after each pair of participants. A fresh gel block was used at the beginning of each data collection day to avoid multiple advancements through the same area, ensuring consistent skin and subcutaneous tissue simulation. Subjects were also queried in advance regarding their preference for glove usage.
Outcome measures
To quantitatively assess needle performance, collected data included the initial and final (after 1 cm catheter advancement) three-dimensional positions (x, y, z) and orientations (pitch, yaw, roll) of the needle tip. From these data, the following metrics were calculated:
Displacement (mm): The straight-line distance between the needle tip’s starting and final positions. It served as a primary indicator of the needle tip’s stability. The displacement was calculated from its individual components along the X (lateral), Y (anteroposterior), and Z (superoinferior) axes.
Total path length (mm): The cumulative scalar distance traversed by the needle tip along its entire path. Akin to a car’s odometer, it recorded all movement, including any wandering or corrective adjustments, providing insight into the overall smoothness and efficiency of motion.
Maximum excursion (mm): The single greatest straight-line distance from the needle tip’s starting position to any point along its movement path. This variable highlights the peak deviation.
Axial movement (mm): The component of displacement that occurred parallel to the needle’s initial insertion axis. A positive value signifies a forward advancement of the needle while a negative value indicates a net retraction.
Radial movement (mm): The component of displacement that occurred perpendicular to the needle’s initial insertion axis. It quantifies lateral deviation or “off-target” drift and is always expressed as a positive value.
Following participation, enrolled subjects completed a questionnaire that collected general demographic information, PVAD placement experience (including preferred advancement technique), and feedback on their experience with the study procedures and simulator. The feedback form was developed to (1) identify potential correlations between demographic or professional factors and perceptions of catheter advancement techniques and (2) evaluate the perceived ease and effectiveness of each technique, as well as their confidence in performing them. See Appendix 1 for more details on the questionnaire.
Statistical analysis
Analyses were performed in R version 4.4.3 using the rstatix R package version 0.7.2.999. 18 They were based on average measures across three trials for each technique and participant, and missing data (less than 5%) were handled by listwise deletion. A one-way repeated-measures analysis of variance (RM-ANOVA) was conducted to compare the three catheter advancement techniques. To examine whether hand preference moderated technique effects, a two-way mixed analysis of variance (mixed ANOVA) was performed, with catheter technique as the within-subject factor and hand preference as the between-subject factor.
Prior to hypothesis testing, each of the five continuous outcome variables was screened for outliers (values beyond Q1 − 1.5 × IQR or Q3 + 1.5 × IQR). Normality of distributions at each level of the within-subject factor was assessed using the Shapiro-Wilk test and Q-Q plots. Homogeneity of variance for the between-subject factor was evaluated with Levene’s test. Sphericity in the repeated-measures factor was tested using Mauchly’s test, and Greenhouse-Geisser corrections were applied when the assumption was violated. Among the five outcomes, only Total Path Length showed a violation of sphericity, and therefore the Greenhouse–Geisser correction was applied for this variable (ε = 0.686). Box’s M test was used to assess the homogeneity of covariance matrices across levels of the between-subject factor.
While all assumptions were met for the RM-ANOVA, half of the outcome variables violated assumptions related to homogeneity of variance or covariance in the mixed ANOVA. Therefore, a robust mixed ANOVA was performed for those outcomes using the WRS2 R package version 1.1-6. 19 This method is based on 20% trimmed means, which reduce the influence of outliers and non-normality while retaining statistical efficiency, and it does not assume normality or equal variance/covariance. All statistical tests were two-tailed with a significance level of α = 0.05. The family-wise error rate was also controlled at α = 0.05 using Bonferroni-adjusted post hoc pairwise comparisons following significant omnibus effects. Generalized eta-squared (η2) was reported for omnibus effects from the RM-ANOVA, partial eta-squared (ηp2) for main and interaction effects from the mixed ANOVA, and Cohen’s d for pairwise comparisons, all as measures of effect size.
In addition, we conducted post hoc power analyses for RM-ANOVA in G*Power using the observed effect sizes. All outcomes showed high achieved power (Needle Tip Displacement = 0.96, Total Path Length = 1.00 (ε = 0.686), Maximum Excursion = 1.00, Axial Movement = 0.974, Radial Movement = 1.00), indicating that the sample size used was adequate for detecting the observed effects.
Results
Participant demographics and experience profiles are summarized in Table 2.
Participant profile.
AA: anesthesiologist assistant; APRN: advanced practice registered nurse; CA: clinical anesthesiology; CRNA: certified registered nurse anesthetist; IV: intravenous; PGY: postgraduate year; RN: registered nurse.
Data are presented as number (percentage) of respondents; total n = 78.
Quantitative analysis by technique
All quantitative data and associated statistical analysis are consolidated within Table 3. Cells shaded in red demonstrate relatively poor performance, yellow demonstrate moderate performance, and green demonstrate good performance. Data by technique/metric are visualized as violin plots in Figure 2.
Consolidated quantitative data and statistical analysis.
ANOVA: analysis of variance; FDR: false discovery rate; ns: not significant.
Summary statistics and mixed-model ANOVA for five needle tip motion metrics across three advancement modes. Columns report mean ± SD, the overall mode effect (F/p/η2), and FDR-adjusted pairwise comparisons with Cohen dz (ns > 0.05).
Violin plot. Comparison of needle tip kinematics across the three catheter-advancement techniques. Gray lines join paired trials from the same participant; boxes show medians and interquartile ranges within the kernel-density violins. Asterisks mark FDR-adjusted post hoc differences (*⩽0.05; **⩽0.01; ***⩽0.001; ****⩽0.0001; ns > 0.05). FDR: false discovery rate; ns: not significant.
Subanalysis: Interaction effects of mode and preferred technique
A mixed ANOVA revealed the significant interactions between mode and preferred technique for both axial and radial movement. For axial movement, in the two-person mode, participants who preferred one-handed operation showed markedly lower movement than those preferring two-handed operation (t = 2.63, p = 0.016, mean difference = −0.98, 95% CI [−1.75, −0.20], d = 0.51, medium). For radial movement, in the one-person–two-hands mode, participants who preferred two-handed operation exhibited lower radial movement than those preferring one-handed operation (t = 3.33, p = 0.002, mean difference = 0.16, 95% CI [0.06, 0.26], d = 0.55, medium). These results suggest that users’ preferred techniques meaningfully influence performance, but their impact emerges only under specific operational conditions.
Qualitative results of techniques
Participants’ subjective experiences with each technique were evaluated using Likert scale questionnaires. The perceived ease of performance, effectiveness, and overall confidence in PVAD insertion (Figure 3) for each technique are illustrated below.
Likert scale ratings. Stacked bars show respondent ratings (n ≈ 78 each) for ease, effectiveness, and overall confidence for one-handed, two-handed, and two-person PVAD insertion techniques. Darker blues indicate “very easy/effective/confident”; reds indicate difficulty or lack of confidence. Two-handed advancement garnered the highest proportion of top-tier ratings, whereas the one-handed method was most often judged difficult or ineffective. PVAD: peripheral venous access device.
Discussion
This simulator-based study provides novel evidence that catheter advancement technique influences inadvertent needle tip movement during the critical unsheathing phase of PVAD placement. The data illustrate that the technique choice meaningfully influenced the motion and the two-handed catheter advancement technique consistently produced the smallest displacements, excursions, and path lengths, indicating superior needle tip stability (Figure 2, Table 3).
Comparative performance of the three techniques
Mean needle tip displacement was lowest with two-handed advancement (1.98 mm) and highest with one-handed (2.54 mm; p = 0.01), suggesting that using one hand to both steady the hub and advance the catheter compromises fine control. Total path length echoed this finding: one-handed advancement more than doubled the distance traveled (9.23 mm) compared with two-handed (3.93 mm) and two-person (3.81 mm) techniques (p < 0.001). Radial (side-to-side) movement was also greatest with one hand (0.74 mm vs 0.53 mm; p < 0.001).
The two-person method matched two-handed performance for displacement and excursion but exhibited greater axial motion (1.65 mm vs 0.78 mm two-handed; p = 0.001). This likely reflects minor asynchrony between operator and assistant; while lateral drift is restrained, forward/backward motion is harder to coordinate. Importantly, the narrow interquartile range for two-person trials suggests that when the two operators are well-coordinated, variability is low and overall performance can approach that of the two-handed single-operator technique, despite higher axial motion on average.
Like path length, the one-handed technique led to significantly greater maximum excursion of the needle tip (mean 3.44 mm) compared to the two-handed (2.33 mm) and two-person techniques (2.56 mm; p < 0.001 for both). Maximum excursion highlights the single furthest deviation from the starting point. A larger maximum excursion might represent a momentary loss of fine needle tip control. The comparable performance of the two-handed and two-person techniques (p = 0.80) suggests both can mitigate these larger deviations.
Beyond procedural performance, an important consideration is how needle tip movement relates to patient outcomes. Uncontrolled or excessive needle movement is believed to be a direct contributor to vein injury.20–22 For example, biomechanical modeling has shown that needle-induced deformation of the vein wall can lead to localized endothelial cell compression and damage, potentially initiating inflammatory and thrombotic processes. 23
Each kinematic metric signals a specific hazard to the vessel wall. Radial motion swings the tip sideways, scraping the intima or perforating the thin vein wall. A large maximum excursion represents a single, abrupt jump that can pierce or lacerate a fragile vein. An extended path length multiplies the number of vessel wall contacts, bruising endothelium and fostering phlebitis. Excess axial movement (forward-backward drift) risks over-advancement, subintimal tunneling, or withdrawal into the puncture tract, all of which compromise lumen integrity. Finally, overall displacement integrates these effects, with greater net needle tip wander correlating to a higher cumulative vein trauma load.
Clinical implications
Uncontrolled needle movements are a plausible mechanistic link to endothelial injury, inflammation, and early catheter failure. 23 Explicitly connecting the kinematic outcomes to published biomechanical thresholds suggests that the measured movements frequently exceed the physiological tolerance of endothelial cells. Biomechanical modeling indicates that the effective margin for error is on the order of a millimeter: needle tip displacements of 0.9–1.1 mm are associated with wall shear stress ⩾2 Pa and shear rates up to 10,000 s−1 near the catheter tip, conditions associated with endothelial injury. 24 Furthermore, if these excursions result in wall impingement, penetrations as superficial as 3.6 µm exert contact pressures that compress essentially the full thickness of the intimal layer. 20 These thresholds are clinically precarious given that average needle tip movement during cannulation has been observed to be ~6 mm. 25 Consequently, current vascular access guidelines classify infiltration from side- or back-wall perforation as cannulation-related vessel injury and stress minimizing cannulation complications, underscoring that the practical window for safe needle manipulation is extremely narrow.26,27
The larger excursions and longer paths seen with one-handed advancement therefore have plausible clinical relevance: they may translate into higher rates of infiltration, phlebitis, or shorter dwell times in vivo. By contrast, the two-handed technique’s tight control—and the two-person technique when well-coordinated—should minimize intimal trauma.
These results extend prior work on ultrasound-guided cannulation, where studies have reported no meaningful differences in success rates or procedure times between one-operator and two-operator techniques.28,29 Consistent with those observations, our kinematic data indicate that adding a second operator does not inherently improve needle control when a skilled clinician can stabilize the hub and advance the catheter with a two-handed technique. Operationally, however, two-person advancement is unlikely to be feasible as a routine hospital workflow because it requires real-time coordination of an additional operator and may be constrained by bedside logistics and competing clinical demands; it is most relevant when a single operator cannot reliably stabilize and advance simultaneously (e.g. constrained positioning or significant patient movement). Operator fatigue and ergonomic load may further modulate these kinematic profiles. Sustaining fine motor control with a single hand over repeated insertions places greater continuous demand on the dominant hand and shoulder girdle than distributing the task across two hands or two people. Future work should quantify how performance changes over time and under high-workload conditions.
Practice and training recommendations
Current clinical standards, specifically the 2024 Infusion Therapy Standards of Practice and the Association of Vascular Access (AVA) Standards of Care, have established strictly defined requirements for “Vessel Health and Preservation.”30,31 Though there is currently no delineation of recommended advancement technique, these guidelines explicitly state that practitioner competency must be validated through demonstrated psychomotor skills rather than mere clinical tenure. Crucially, this requirement spans all clinical domains; recent literature highlights that standardized, simulation-based training is as critical for resident physicians addressing training gaps in graduate medical education as it is for nursing proficiency.32,33
In practical terms, adhering to these standards requires technique modifications—such as using an anchor hand to stabilize the needle, advancing the catheter in a controlled two-handed technique, and promptly securing the catheter—to minimize the vein trauma prohibited by current guidelines. This study’s quantitative findings provide evidence for these practices by demonstrating how each technique influences needle tip movement. They also suggest that integrating the two-handed advancement method into training curricula could improve outcomes for practitioners, particularly novices. Consistent with evidence that simulation bridges the gap between theory and practice, simulator-based curricula that provide real-time feedback on needle tip movement could accelerate mastery of the two-handed technique, particularly for novices who currently default to one-handed advancement. 33
Limitations
While the phantom model standardizes tissue conditions, it cannot fully replicate vascular compliance, human tissue variability, or patient movement. Only 18-Ga catheters were evaluated; gauge or catheter design could modulate kinematics. Smaller-bore needles such as 24-Ga and 22-Ga have lower bending stiffness and therefore greater flexibility under load, whereas larger-bore needles such as 20-Ga and 18-Ga are comparatively stiffer, so tip kinematics and associated endothelial forces likely differ by gauge and should be characterized in future work.34,35 If a PVAD with an integrated wire is used, it is a 1 person, 2 hands technique by default that does not necessitate a second person. Participants were drawn from a single center; although experience levels varied, local practice norms may bias technique preferences. Finally, we could not measure clinical endpoints such as first-pass success, pain, or complication rates; these should be explored in future clinical studies.
Conclusions
This research provides novel quantitative data on PVAD advancement and supports two‑handed self-advancement as the technique with the most effective control of needle tip motion during PVAD placement. Emphasizing this technique in procedural training may lower endothelial injury and PVAD failure rates. Future clinical studies should validate these biomechanical advantages in patient populations.
Supplemental Material
sj-docx-1-jva-10.1177_11297298261430813 – Supplemental material for Effect of catheter advancement technique on needle tip motion during peripheral intravenous insertion
Supplemental material, sj-docx-1-jva-10.1177_11297298261430813 for Effect of catheter advancement technique on needle tip motion during peripheral intravenous insertion by Mayank Kotadia, S Hamad Sagheer, Christopher Samouce, Rachael Ahn, Hannah Kavelak, Samsun Lampotang and Nikolaus Gravenstein in The Journal of Vascular Access
Footnotes
Appendix 1
Acknowledgements
We are grateful for the technical expertise of the Center for Safety, Simulation & Advanced Learning Technologies (CSSALT) department. We express our appreciation to the University of Florida Health for providing the platform to conduct this research, and to the nursing staff and all other healthcare professionals who generously volunteered their time and expertise as participants in this study. Finally, we acknowledge the support of the University of Florida Department of Anesthesiology and thank Bryan Penberthy, MFA, MWC, of the University of Florida College of Medicine Department of Anesthesiology’s Communications & Publishing office for his editorial assistance with this manuscript.
Author contributions
Mayank Kotadia: Methodology, Software, Validation, Formal analysis, Investigation, Resources, Data Curation, Writing—Original Draft, Writing—Review & Editing, Visualization, Project administration. S Hamad Sagheer: Conceptualization, Methodology, Software, Validation, Investigation, Data Curation, Resources, Writing—Original Draft, Writing—Review & Editing, Supervision, Project administration. Christopher Samouce: Methodology, Software, Validation, Resources, Data Curation, Writing—Original Draft, Writing—Review & Editing, Visualization. Rachael Ahn: Formal analysis, Writing—Review & Editing. Hannah Kavelak: Investigation, Provision, Project administration. Samsun Lampotang: Conceptualization, Methodology, Software, Resources, Writing—Original Draft, Writing—Review & Editing, Supervision, Project administration. Nikolaus Gravenstein: Conceptualization, Methodology, Resources, Writing—Original Draft, Writing—Review & Editing, Supervision, Project administration.
Declaration of conflicting interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The authors received no financial support for the research, authorship, and/or publication of this article.
Data availability
Deidentified data for per-trial needle tip kinematics and post participation questionnaire responses are available from the corresponding author (
Ethical considerations
This prospective, within-subject crossover study, conducted at the University of Florida Shands Hospital between September 2024 and May 2025, received approval from the University of Florida’s Institutional Review Board (UFIRB #02400590).
Consent to participate
Consenting participants were enrolled if they were at least 18 years old and if they had placed peripheral IV catheters in the course of their work or training. Participants were excluded if they did not have at least 1 year of clinical experience.
Reporting guidelines adherence
This randomized study is reported in accordance with the CONSORT 2025 Statement, with the CONSORT extension for healthcare Simulation-Based Research (CONSORT-SBR) applied where relevant.
Generative AI technologies statement
Generative AI tools were not used in the preparation of this manuscript or in any aspect of the underlying research. The authors alone are responsible for the accuracy and integrity of the work.
ORCID iDs
Supplemental material
Supplemental material for this article is available online.
References
Supplementary Material
Please find the following supplemental material available below.
For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.
For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.
