Ultrasound-Guided Workflow for Peripheral Venous Access Selection, Maintenance, and Dynamic Catheter Adjustment in Adult Hospitalized Patients

Summary

This protocol describes an ultrasound-guided workflow for peripheral venous access selection, closed-loop catheter maintenance, and dynamic adjustment in adult hospitalized patients requiring intravenous infusion therapy.

Abstract

Peripheral venous access is the most frequently performed invasive procedure in hospitalized patients; however, conventional experience-based management is subjective and associated with higher complication rates and lower nursing efficiency. This single-center retrospective before-and-after study evaluated a reproducible ultrasound-guided workflow for peripheral venous access selection, maintenance, and dynamic catheter adjustment. A total of 113 hospitalized patients receiving intravenous infusion therapy between May 1, 2024, and August 31, 2025, were included. The control group (n = 61) received traditional nursing care, whereas the observation group (n = 52) received an ultrasound-guided integrated nursing model incorporating vascular assessment, predefined access-selection criteria, closed-loop maintenance, and protocol-based dynamic adjustment. Outcomes included puncture performance, catheter dwell time and utilization, complications, nursing efficiency, health economic outcomes, and patient satisfaction. Outcome data were extracted from routine clinical records, and blinded outcome assessment was not feasible because group allocation was determined by the implementation period. Baseline characteristics were comparable between groups (P > 0.05). Compared with the control group, the observation group demonstrated a higher access-selection matching rate (86.5%; unadjusted P = 0.026), improved first-attempt puncture success (88.5% vs. 73.8%; unadjusted P = 0.049), lower puncture pain (VAS 1.65 ± 0.84; P < 0.001), longer catheter dwell time (P < 0.001), fewer venous accesses per treatment course (1.04 ± 0.19 vs. 1.64 ± 0.66; P < 0.001), lower overall complication rates (11.5% vs. 29.5%; unadjusted P = 0.020), faster complication detection and management (P ≤ 0.001), reduced daily nursing time (14.73 ± 4.56 vs. 27.64 ± 7.44 min; P < 0.001), lower direct venous access-related medical costs, and improved patient satisfaction, while hospital stay remained unchanged (P = 0.935). These findings indicate that integrating vascular ultrasound throughout the peripheral venous access pathway provides a standardized workflow that improves clinical outcomes, enhances nursing efficiency, and reduces medical risk.

Introduction

Peripheral venous access is the most basic and also the most important invasive route for clinical treatment. Approximately 70% to 80% of hospitalized patients require intravenous infusion therapy, and more than 90% of medication administration procedures are performed through peripheral veins¹. The quality of access management directly affects treatment continuity, patient safety, and nursing efficiency, making it a key component of clinical nursing quality control that should not be overlooked². Traditional peripheral venous access management, however, relies entirely on visual inspection and experiential judgment by nurses. As a result, it is highly subjective and often varies considerably from one individual to another³. Clinical data have shown that, under visual assessment alone, the first-attempt puncture success rate is only 62% to 71%, and in patients who are obese, elderly, edematous, or have poor vascular conditions, this rate falls below 50%⁴. Repeated puncture not only increases patient discomfort but may also cause irreversible vascular injury and compromise subsequent long-term treatment⁵. In addition, the lack of standardized post-procedural maintenance procedures and dynamic assessment mechanisms has kept the incidence of venue-related access-related complications at a persistently high level. This not only increases the economic burden on patients but also adds considerably to the nursing workload⁶.

In recent years, vascular ultrasound has gradually been introduced into clinical nursing practice and has improved puncture success in patients with difficult venous access⁷. At the same time, the full-process management concept of “precise selection - closed-loop maintenance - dynamic adjustment” has also begun to attract attention, and some institutions have attempted to apply it to peripheral venous access management. Even so, this model is still at an exploratory stage and has not yet developed into a mature standardized system. In some reports, for example, the three components were simply combined in parallel, without meaningful integration or effective information flow among them⁸. In others, ultrasound assessment data were used mainly for pre-puncture selection and did not effectively guide subsequent adjustment of maintenance frequency or early warning of complications⁹. In addition, operating procedures vary considerably across institutions, and the lack of unified quality control standards makes published findings difficult to reproduce or generalize¹⁰. Existing studies are also limited by a rather narrow evaluation framework. Most have focused only on clinical safety outcomes such as puncture success and complication rates, while comprehensive assessment of nursing efficiency, health economic benefit, and the experience of both patients and healthcare staff remains insufficient^11,12.

To address these gaps, the present study established a reproducible ultrasound-guided workflow for peripheral venous access selection, maintenance, and dynamic catheter adjustment, built around the integrated nursing process of “precise selection - closed-loop maintenance - dynamic adjustment.” This workflow is intended for adult hospitalized patients receiving inpatient infusion therapy, particularly those with difficult venous access or poor vascular conditions and is designed for use by ultrasound-capable intravenous therapy nurses or vascular access teams in routine inpatient care. This model moves beyond the conventional view that ultrasound is used only for puncture guidance and instead applies ultrasound assessment throughout the entire life cycle of venous access. Objective indicators, including venous diameter, vessel wall thickness, and blood flow velocity, were quantified to formulate standardized criteria for access selection. A closed-loop management mechanism was also developed for early complication identification, graded intervention, and outcome tracking, while the access management strategy was adjusted in real time according to changes in the patient's treatment plan and vascular condition. Systematic evaluation of this workflow may provide practical evidence for standardized and refined management of peripheral venous access, while also carrying clinical implications for reducing nursing risk, improving service quality, and alleviating patient burden.

Protocol

This study was approved by the Medical Ethics Committee of The Fourth Affiliated Hospital of Soochow University (Ethic Code No: 251264). As this was a retrospective analysis, informed consent was waived. The study was conducted in strict accordance with the ethical principles of the Declaration of Helsinki.

1. Personnel and Procedural Preparation

1. Assign the workflow to a specialized intravenous therapy nursing team whose members have completed standardized training and competency assessment. Ensure that each operator is qualified in vascular ultrasound assessment, catheter-to-vessel matching, ultrasound-guided cannulation, phlebitis grading, and protocol-based catheter adjustment.
2. Prepare the ultrasound system listed in the Table of Materials, peripheral intravenous catheters, sterile ultrasound gel, a probe cover, skin antiseptic, transparent dressings, 0.9% sodium chloride solution, fixation materials, and waste containers. Verify that the ultrasound probe, Doppler function, and electronic calipers operate correctly before examining the patient.
   NOTE: Use only catheter gauges for which the manufacturer-reported outer diameter is available; do not infer the catheter outer diameter from the nominal gauge alone.
3. Position the patient supine or seated according to the clinical condition and place the target upper extremity on a stable support with the forearm comfortably extended. Keep the limb relaxed and the intended scanning and cannulation area fully exposed.

2. Ultrasound Assessment and Catheter-to-Vessel Matching

1. Apply ultrasound gel to the target area and place the probe lightly on the skin. Maintain sufficient contact to obtain a clear image without compressing the superficial vein.
2. Scan each candidate vein in the short-axis view to identify the vein, adjacent artery, compressibility, depth, and surrounding tissue. Rotate the probe 90° and use the long-axis view to confirm vessel continuity, intraluminal patency, wall regularity, and an unobstructed puncture path.
3. Quantify the candidate vessel
   1. Freeze a short-axis image when the venous lumen is fully open and measure the internal diameter from inner wall to inner wall at the widest point. Repeat the measurement three times without probe compression and record the mean value.
   2. Measure venous depth vertically from the skin surface to the anterior vessel wall at the same segment. Measure vessel wall thickness three times at the clearest visible wall interface and record the mean value.
   3. Position the Doppler sample volume in the center of the lumen and maintain an insonation angle of ≤60°. Record peak blood-flow velocity from three consecutive stable waveforms and compare the mean value with that of a proximal segment of the same vein or the homologous contralateral vein.
      ​NOTE: Record the anatomical location of the measured segment and use the same limb position, probe pressure, and measurement method during subsequent reassessment.
4. Determine vessel eligibility and catheter suitability.
   1. Exclude any vessel with a mean wall thickness >0.5 mm, intraluminal thrombotic echo, marked stenosis, poor compressibility, or a peak blood-flow velocity reduction >30% relative to the proximal or contralateral reference segment. From the remaining vessels, select a straight and patent segment located away from a joint.
   2. Calculate the catheter-to-vessel ratio as follows: catheter-to-vessel ratio (%) = catheter outer diameter (mm)/mean internal venous diameter (mm) ×100. Record the measured venous diameter, catheter outer diameter, and calculated ratio before cannulation.
   3. Select the smallest catheter gauge compatible with the prescribed infusion and use the selected vessel only when the catheter-to-vessel ratio is ≤45%. When the ratio exceeds 45%, select a catheter with a smaller outer diameter or choose another eligible vessel; use an alternative vascular access device when neither option is clinically appropriate.

3. Ultrasound-Guided Cannulation and Postprocedural Handling

CAUTION: Treat blood and all blood-contaminated materials as biological hazards, needles and stylets as percutaneous sharps hazards, and alcohol- or chlorhexidine-based skin antiseptics as flammable and irritant chemical hazards. Wear disposable nitrile gloves, a fluid-resistant long-sleeved gown, a surgical mask, and goggles or a face shield during skin preparation, cannulation, catheter removal, and contaminated-waste handling; keep antiseptics away from ignition sources and allow the prepared skin to dry completely before puncture.

1. Disinfect the puncture area according to the institutional standard and allow the antiseptic to dry completely. Perform ultrasound-guided cannulation using either the short-axis out-of-plane or long-axis in-plane technique while continuously confirming the position of the needle tip relative to the target vein.
2. Confirm intravascular catheter placement, secure the catheter, and cover the site with transparent dressing. Document the selected vein, catheter gauge and outer diameter, venous diameter, catheter-to-vessel ratio, ultrasound measurements, number of puncture attempts, procedure time, and puncture pain score.
   CAUTION: Do not recap, bend, break, or manually detach used needles or stylets; discard them immediately into a closable, leak-resistant, puncture-resistant sharps container. Place used catheters, blood-contaminated gauze, dressings, gloves, and probe covers in a labeled biohazard-waste container; collect unused or spilled antiseptic and chemically contaminated absorbent materials in the designated chemical-waste container, place only uncontaminated packaging in general waste, and clean and disinfect reusable ultrasound probes and cables after each patient with a manufacturer-compatible hospital-grade disinfectant.

4. Daily Reassessment and Dynamic Catheter Adjustment

1. Have an ultrasound-qualified intravenous therapy nurse perform and document the daily ultrasound reassessment at 8:00 a.m. Have the bedside nurse inspect the catheter site during each shift and request immediate reassessment when pain, erythema, swelling, leakage, resistance to flushing, or another catheter-related abnormality is observed.
2. Reassess catheter position, venous wall thickness, peak blood-flow velocity, compressibility, puncture-site appearance, patient-reported symptoms, and dressing integrity at the previously documented vascular segment. Compare the measurements with the baseline and reference values, and limit routine catheter dwell time to 96 h unless an earlier adjustment criterion is met.
3. Apply the catheter-adjustment criteria.
   1. Repeat the ultrasound measurement after releasing probe pressure when an isolated ultrasound abnormality is detected. Stop using the catheter and change the site before the next infusion when venous wall thickness exceeds 0.5 mm or peak blood-flow velocity decreases by >30% relative to the baseline or reference value.
   2. Remove the catheter immediately when grade ≥2 phlebitis, infiltration or extravasation, persistent leakage, unresolved catheter occlusion, suspected thrombosis, or suspected catheter-related infection is identified. Replace only the dressing when its integrity has failed but catheter stability, puncture-site sterility, and vascular findings remain acceptable.
4. Grade and manage phlebitis.
   1. Assess and document the phlebitis grade during each scheduled or symptom-triggered review. Reassess and record the grade after every intervention.
      NOTE: Define grade 0 as no signs or symptoms; grade 1 as access-site erythema with or without pain; grade 2 as access-site pain accompanied by erythema and/or edema; grade 3 as pain, erythema and/or edema accompanied by streak formation and a palpable venous cord; and grade 4 as grade 3 findings accompanied by a palpable venous cord >2.5 cm and/or purulent drainage.
   2. For grade 1 phlebitis, pause the infusion, provide local care, and repeat the clinical and ultrasound assessment. For grade ≥2 phlebitis, remove the catheter, establish access at another site when infusion must continue, provide symptomatic treatment according to institutional policy, and document follow-up until resolution. Details are shown in Table 1.

5. Outcome Assessment and Statistical Analysis

1. Access selection matching and puncture-related indicators
   1. Access selection matching was defined as the selection of a patent and compressible vessel without venous wall thickness >0.5 mm, local thrombosis, marked stenosis, or a >30% reduction in peak blood-flow velocity, together with a catheter-to-vessel ratio ≤45%, calculated as the manufacturer-reported catheter outer diameter divided by the mean internal venous diameter ×100.
   2. A selection was classified as unmatched when any criterion was not met or when the catheter outer diameter or venous diameter required to calculate the ratio was not documented. Selections that failed to meet any of these criteria, or lacked sufficient documentation for adjudication, were classified as unmatched.
   3. Retrospective adjudication was performed using the original nursing and ultrasound records; complete blinding to group allocation was not feasible because ultrasound documentation was part of the intervention.
   4. Puncture-related indicators included the first-attempt puncture success rate (defined as the percentage of successful first-attempt punctures among all puncture procedures), the incidence of second or subsequent puncture attempts, mean puncture procedure time (from preparation of materials to successful puncture and fixation), and patient pain score during puncture, which was assessed using the visual analog scale (VAS)¹³, where 0 indicates no pain, and 10 indicates severe pain.
2. Indicators of catheter dwell time and utilization included the actual dwell time of each venous access, the rates of planned and unplanned catheter removal, and the total number of venous accesses required during a single treatment course.
3. Complication-related indicators included the overall complication rate; the incidence of each specific complication, including phlebitis, leakage/extravasation, catheter occlusion, thrombosis, and catheter-related infection; time to complication occurrence (from successful puncture to confirmed complication); time to complication detection (from complication onset to nurse recognition); mean time required for complication management; the number of additional punctures caused by complications; and the outcomes of severe complications.
4. Nursing efficiency indicators were calculated from the nursing scheduling system and nurses' work records and included mean daily venous nursing time per patient (covering puncture, maintenance, complication management, and handover time), the mean number of venous accesses managed by each nurse per shift, the additional nursing workload caused by unplanned catheter removal, the incidence of venous access-related nursing errors, the mean daily overtime attributable to venous access problems, and the mean handover time for venous access at shift change.
5. Health economic indicators included the direct medical cost related to venous access per patient from the hospital perspective, including indwelling catheters and related consumables, medications, and examinations used for complication management, and nursing labor costs calculated according to recorded venous-access nursing time and the local hourly wage standard for nursing staff. Fixed overhead costs, equipment depreciation, patient transportation costs, productivity loss, and other indirect societal costs were not included; therefore, the economic analysis was limited to direct venous access-related hospital costs.
6. Patient satisfaction was evaluated on the day of discharge using the hospital's standardized nursing service satisfaction questionnaire, which covered four dimensions: overall satisfaction, puncture technique, pain management, and service attitude. The questionnaire was administered as part of the routine discharge nursing-quality survey; however, because the retrospective records did not allow confirmation that all questionnaires were collected by personnel independent of bedside catheter care, satisfaction outcomes were interpreted as supportive patient-reported indicators.
7. Statistical Analysis
   1. Data conforming to a normal distribution were expressed as mean ± standard deviation (‾χ ± s), and intergroup comparisons were performed using the independent-samples t test; however, for complication-process variables analyzed only among patients who developed complications, Mann-Whitney U tests were used, and values were presented as median [interquartile range] because of the small subgroup sizes.
   2. Unless otherwise specified, all between-group analyses were based on the full analysis cohort of 61 patients in the control group and 52 patients in the observation group.
   3. Analyses of time to complication detection, time required for complication management, additional punctures caused by complications, and effective complication management were restricted to patients who developed at least one venous access-related complication, comprising 18 patients in the control group and 6 patients in the observation group.
   4. Data not conforming to a normal distribution were expressed as median and interquartile range [M (P25, P75)] and were compared using the Mann-Whitney U test. Categorical variables were expressed as numbers and percentages (n, %) and were compared using the χ² test or Fisher's exact test. Ordinal data were compared using the Mann-Whitney U test.
   5. All tests were two-sided, and P < 0.05 was considered statistically significant. Because this exploratory evaluation included multiple clinical, process, and economic endpoints, P values were reported as unadjusted; no formal multiplicity correction was applied, and borderline findings were interpreted cautiously.
   6. No formal a priori sample size calculation was conducted because all eligible patients treated during the predefined pre-implementation and post-implementation periods were included.
   7. A descriptive post-hoc power assessment based on the observed first-attempt puncture success rates of 73.8% and 88.5% indicated approximately 52.6% power at a two-sided alpha level of 0.05; therefore, the study was considered exploratory, and secondary or subgroup outcomes were interpreted with caution.

Results

Study Design and Participants

For evaluation of this workflow, this study used a single-center retrospective before-and-after design based on a hospital-level nursing practice change. Consecutive eligible patients treated during the predefined pre-implementation and post-implementation periods were included, and outcome data were extracted from routine clinical, nursing, and hospital information systems. Hospitalized patients who received intravenous infusion therapy at our ho...

Discussion

This single-center retrospective before-and-after study explored the clinical value of an integrated nursing model of “precise selection - closed-loop maintenance - dynamic adjustment” for peripheral venous access based on vascular ultrasound assessment. The findings showed that this model offered clear advantages in improving access management quality, reducing medical risk, optimizing nursing processes, and controlling healthcare costs, thereby providing new practical evidence for the standardized managemen...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
0.9% Sodium Chloride Injection	Sichuan Kelun Pharmaceutical Co., Ltd. (Chengdu, China)	/	Routine flushing and locking solution after intravenous infusion
Disposable Closed Intravenous Catheter	Becton Dickinson Medical Devices (Shanghai) Co., Ltd. (BD)	/	Used for establishing upper extremity peripheral venous access
Disposable Intravenous Infusion Set	Shandong Weigao Group Medical Polymer Products Co., Ltd.	/	0.7 mm × 25 mm specification; Special consumable for clinical intravenous drug administration
Disposable Sterile Transparent Dressing	3M China Co., Ltd.	1624W	Fixation and protection of venous puncture site, routine replacement every 7 days
Electronic Medical Record System (EMR)	Beijing Jiahui Hemkang Information Technology Co., Ltd.	version 6.0	Extracts patient clinical diagnosis and treatment, laboratory tests, underlying diseases, and combined medication records
Hospital Information System (HIS)	Donghua Medical Technology Co., Ltd.	version 5.0	Extracts patient basic information, diagnosis and treatment records, and direct medical cost data related to venous access
Medical Electronic Timer	Shanghai Medical Device Co., Ltd.	JS-03	Accurately records time indicators such as puncture operation time, complication handling time, and handover time
Nursing Information System (NIS)	Weining Health Technology Group Co., Ltd.	version 4.5	Extracts nursing scheduling, venous access care operations, complication handling, and handover records
Portable Color Doppler Ultrasound Machine	Shenzhen Mindray Biomedical Electronics Co., Ltd.	M7	Quantitative assessment of peripheral venous vessel diameter, wall thickness, blood flow velocity and real-time guidance for puncture
SPSS Statistical Software	IBM Corp. (Armonk, New York, USA)	version 26	Statistical analysis of all measurement, count and ordinal data for research
Visual Analog Scale (VAS) Ruler	Jiangsu Yuyue Medical Equipment Co., Ltd.	YV-01	Used for quantitative assessment of patient pain level during puncture