Ultrasound-guided catheterisation of the subclavian vein: freehand vs needle-guided technique

Automated angular measurement for puncture angle using a computer-aided method in ultrasound-guided peripheral insertion

Ultrasound guidance has become the gold standard for obtaining vascular access. Angle information, which indicates the entry angle of the needle into the vein, is required to ensure puncture success. Although various image processing-based methods, such as deep learning, have recently been applied to improve needle visibility, these methods have limitations, in that the puncture angle to the target organ is not measured. We aim to detect the target vessel and puncture needle and to derive the puncture angle by combining deep learning and conventional image processing methods such as the Hough transform. Median cubital vein US images were obtained from 20 healthy volunteers, and images of simulated blood vessels and needles were obtained during the puncture of a simulated blood vessel in four phantoms. The U-Net architecture was used to segment images of blood vessels and needles, and various image processing methods were employed to automatically measure angles. The experimental results indicated that the mean dice coefficients of median cubital veins, simulated blood vessels, and needles were 0.826, 0.931, and 0.773, respectively. The quantitative results of angular measurement showed good agreement between the expert and automatic measurements of the puncture angle with 0.847 correlations. Our findings indicate that the proposed method achieves extremely high segmentation accuracy and automated angular measurements. The proposed method reduces the variability and time required in manual angle measurements and presents the possibility where the operator can concentrate on delicate techniques related to the direction of the needle.

Ultrasound-guided subclavian vein catheterisation with a needle guide (ELUSIVE): protocol for a randomised controlled study

INTRODUCTION

Central venous catheters are indispensable in modern healthcare. Unfortunately, they are accompanied by minor as well as major complications, leading to increased morbidity, mortality and costs. Immediate insertion-related complications (mechanical complications) have decreased due to the implementation of real-time ultrasound guidance, but they still occur and additional efforts to enhance patient safety are warranted. This study aims to investigate whether the use of a needle guide mounted on the ultrasound probe in subclavian catheterisations may decrease the number of catheterisations with >1 skin puncture (primary outcome).

METHODS AND ANALYSIS

This is an investigator-initiated, non-commercial, randomised, controlled, parallel-group study conducted at Skåne University Hospital, Lund, Sweden. Adults (≥18 years) with a clinical indication for a subclavian central venous catheter and the ability to give written informed consent will be eligible for inclusion. Exclusion criteria include subclavian catheterisation deemed unsuitable based on the preprocedural ultrasound examination. Patients will be randomised to catheterisation by certified operators using a microconvex probe (long-axis, in-plane technique) with (n=150) or without (n=150) a needle guide. The ultrasound imaging from the procedures will be recorded and assessed by two reviewers individually. The assessors will be blinded for group affiliation. Secondary outcomes include the total number of skin punctures, mechanical complications, time to successful venous puncture, number of failed catheterisations and operator satisfaction with the needle guide at the end of the study period.Recruitment started on 8 November 2022 and will continue until the sample size is achieved.

ETHICS AND DISSEMINATION

This study was approved by the Swedish Ethical Review Authority (#2022-04073-01) and the Swedish Medical Products Agency (#5.1-2022-52130; CIV-21-12-038367). The findings will be submitted to an international peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT05513378, clinicaltrials.gov.

Improvement of central vein ultrasound-guided puncture success using a homemade needle guide-a simulation study

BACKGROUND

Out-of-plane (OOP) approach is frequently used for ultrasound-guided insertion of central venous catheter (CVC) owing to its simplicity but does not avoid mechanical complication. In-plane (IP) approach might improve safety of insertion; however, it is less easy to master. We assessed, a homemade needle guide device aimed to improve CVC insertion using IP approach.

METHOD

We evaluated in a randomized simulation trial, the impact of a homemade needle guide on internal jugular, subclavian and femoral vein puncture, using three approaches: out-of-plane free hand (OOP-FH), in-plane free hand (IP-FH), and in-plane needle guided (IP-NG). Success at first pass, the number of needle redirections and arterial punctures was recorded. Time elapsed (i) from skin contact to first skin puncture, (ii) from skin puncture to successful venous puncture and (iii) from skin contact to venous return were measured.

RESULTS

Thirty operators performed 270 punctures. IP-NG approach resulted in high success rate at first pass (jugular: 80%, subclavian: 95% and femoral: 100%) which was higher than success rate observed with OOP-FH and IP-FH regardless of the site (p = .01). Compared to IP-FH and OOP-FH, the IP-NG approach decreased the number of needle redirections at each site (p = .009) and arterial punctures (p = .001). Compared to IP-FH, the IP-NG approach decreased the total procedure duration for puncture at each site.

CONCLUSION

In this simulation study, IP approach using a homemade needle guide for ultrasound-guided central vein puncture improved success rate at first pass, reduced the number of punctures/redirections and shortened the procedure duration compared to OOP and IP free-hand approaches.

The Use of a New Device-Assisted Needle Guidance versus Conventional Approach to Perform Ultrasound Guided Brachial Plexus Blockade: A Randomized Controlled Study

Purpose

Ultrasound guidance during nerve blockade poses the challenge of maintaining in-plane alignment of the needle tip. The needle guidance device maintains needle alignment and assists with in-plane needle visualization. The purpose of this study is to evaluate the utility of this device by comparing procedure performance during brachial plexus blockade with the conventional approach.

Methods

After the Institutional Review Board approval and obtaining informed consent, 70 patients receiving either interscalene or supraclavicular nerve blocks were randomly assigned into 2 groups, a conventional approach versus utilizing the needle guidance device. An independent observer recorded: total procedure time; needle insertion time; number of unplanned redirections; and number of reinsertions. Additionally, physician satisfaction and ease of needle visualization were assessed.

Results

Data from seventy patients were analyzed. The median [25th percentile-75th percentile] time to complete the block by the device assisted needle guidance group was 3 (2–3.75) minutes and 4 (3–6) minutes in the conventional approach group (p < 0.001). Additionally, subgroup analyses were performed in the supraclavicular block and interscalene block. Supraclavicular blockade, needle insertion time (median [25th percentile-75th percentile] in seconds) (106 [92–162] vs 197 [140–278]), total procedure time (3 [2–3] vs 4.5 [4–6] in minutes) and unplanned needle redirections (2 [1–5] vs 5.5 [3–9]) were significantly lower in needle guidance group (p < 0.001). With interscalene blockade, needle insertion time (86 [76–146] vs 126 [94–295]) and unplanned needle redirections (2 [1–3] vs 4 [2–8.5]) were significantly lower with needle guidance (p < 0.001), but total procedure time was similar. All the physicians reported that they would use the needle guidance again, and 90% would prefer it for in-plane blocks.

Conclusion

Performing regional blocks using the needle guidance device reduces needle insertion time and unplanned needle redirections in brachial plexus blockade. Moreover, physician satisfaction also improved compared to the use of the conventional technique.

A new method for facilitating ultrasound-guided in-plane cannulation of the subclavian vein: a randomized clinical trial

The objective of this study was to propose a new method for facilitating needle-beam alignment ultrasound-guided in-plane catheterization of the subclavian vein (SCV). Three hundred patients were recruited, and ultrasound examination of the SCV was performed. Then, the patients were divided into two groups and SCV catheterization was performed: ultrasound-guided catheterization with the aiming method (group A) and ultrasound-guided catheterization with needle guide (group NG). The success rate, insertion time, number of skin breaks, number of needle redirections, needle visibility and rate of mechanical complications were documented and compared for each procedure. To depict the optimum long-axis view of the SCV, there was a 30° ± 7.3° angle (rotation) between the long axis of the ultrasound probe and the clavicle, while there was a 39° ± 7.4° angle (tilt) between the ultrasound beam plane and the right chest wall. The aiming method was associated with fewer skin breaks [(mean (IQR): 1 (1–1) times vs 1 (1–2) times, P = 0.009], a shorter time to cannulation [(mean (IQR): 39 (32–48.5) s vs 48 (44–54.8) s, P = 0.000] and more needle redirections [(mean (IQR): 0 (0–1) vs 0 (0–0), P = 0.000]. There were no differences between group A and group NG in the overall success rate, first puncture success rate, needle visibility or mechanical complication rate. In conclusion, during ultrasound-guided in-plane catheterization of the SCV, the aiming method provides comparable needle-beam alignment with a lower cannulation time than the needle guide technique.

Training novice in ultrasound-guided venipuncture: A randomized controlled trial comparing out-of-plane needle-guided versus free-hand ultrasound techniques on a simulator

BACKGROUND

Peripheral intravenous access is a common medical procedure, however, it can be difficult to perform in some patients. Success rates have proved greater with ultrasound guidance. Peripheral intravenous access using ultrasound requires specific training, especially for new ultrasound users. To overcome these difficulties, guidance devices on ultrasound probes are able to control the angle of penetration into tissues. We hypothesized that, and particularly for new ultrasound users, the use of a needle guide (NG) paired with the out-of-plane approach would facilitate puncture of a simulation model of vessel more effectively than similar free hand (FH) techniques.

METHODS

A prospective controlled randomized study was conducted of new ultrasound users using a guide wire introducer needle on gelatine phantom. After a 30-min lecture, one group performed the FH technique and the other group performed the NG technique both in an out-of-plane approach. The main criterion was the number of attempts before success of catheterization of this model of vessel.

RESULTS

Thirty-four nurse anesthetist students participated in the study. The number of attempts before success using the NG technique was significantly lower: 3.7 (±0.9) in the NG group versus 6.7 (±3.3) in the FH group (p = 0.01). In the NG group, 100% of the participants achieved success after the sixth attempt. In the FH group, only 81.25% (n = 13/16) reached success.

CONCLUSION

NG technique has been proved to have a steeper learning curve compared with the FH technique. A study on a learning curve in clinical practice is needed to confirm these results.

Ultrasound probe tilt impedes the needle-beam alignment during the ultrasound-guided procedures

The objective of this study was to identify the factors that complicate the needle visualization in ultrasound-guided in-plane needling procedures. Forty-nine residents were recruited and randomized to insert the simulated blood vessel with four different views including Neutral (the long axis of the probe along the visual axis and the ultrasonic beam vertical to the surface of gel phantom), 45°-rotation (45° angle between the long axis of probe and the operator’s visual axis), 45°-tilt (45° angle between the ultrasonic beam and the surface of gel phantom) and 45°-rotation plus 45°-tilt of probe. Number of needle redirections, insertion time, and needle visibility were documented and compared for each procedure. When the residents faced with 45°-tilt view, the needle redirections (2 vs 0) and insertion time increased significantly (39 vs 16) compared with that of the Neutral view. When faced with 45°-rotation plus 45°-tilt view, the residents’ performance decreased further as compared with that of the 45°-tilt view and the Neutral view. However, there was no performance difference between the Neutral view and 45°-rotation view. In conclusion, during ultrasound-guided in-plane procedures, tilting the ultrasound probe may increase the difficulty of needle-beam alignment.

Static Ultrasound Guidance VS. Anatomical Landmarks for Subclavian Vein Puncture in the Intensive Care Unit: A Pilot Randomized Controlled Study

BACKGROUND

Subclavian vein puncture is commonly used in the intensive care unit (ICU) but is associated with complications.

OBJECTIVE

Our aim was to compare the efficacy and safety of static ultrasound-guided subclavian vein puncture with traditional anatomical landmark-guided subclavian vein puncture in critically ill patients in the ICU.

METHODS

This pilot randomized controlled trial enrolled patients admitted to the ICU and requiring subclavian vein puncture between November 2017 and September 2018. The patients were randomized to ultrasound-guided puncture or anatomical landmark-guided puncture. The primary outcome measure was the puncture success rate. The secondary outcome measures included the number of punctures, rate of success at the first attempt, puncture time (i.e., procedure duration) and incidence of complications.

RESULTS

A total of 194 patients were included in the analyses. Compared with the anatomical landmarks group, the ultrasound group had a higher puncture success rate (91.7% vs. 77.6%; p = 0.007), lower rate of complications (7.3% vs. 20.4%; p = 0.008), and lower incidence of mispuncture of an artery (2.1% vs. 14.3%; p = 0.002). There were no significant differences in the number of punctures and puncture time between the two groups (both, p > 0.05).

CONCLUSIONS

Static ultrasound-guided subclavian vein puncture is superior to the traditional landmark-guided approach for critically ill patients in the ICU. It is suggested that static ultrasound-guided puncture techniques should be considered for subclavian vein puncture in the ICU.

TRIAL REGISTRATION

ChiCTR1900024051.

Shallow-angle needle guide for ultrasound-guided internal jugular venous catheterization: A randomized controlled crossover simulation study (CONSORT)

Background

Needle guides for ultrasound-guided internal jugular venous catheterization facilitate successful cannulation. The ability of a needle guide to prevent a posterior vein wall injury which may secondarily induce lethal complications, is unknown. Previous studies showed that a shallow angle of approach may reduce the incidence of posterior wall injuries. We developed a novel needle guide with a shallow angle of approach for ultrasound-guided venous catheterization and examined whether this needle guide reduces the incidence of posterior wall injuries compared to a conventional needle guide and free-hand placement in a simulated vein.

Methods

This study was a randomized crossover-controlled trial. The primary outcome was the rate of posterior vein wall injuries. Participants had a didactic lecture about three ultrasound-guided techniques using the short-axis out-of-plane approach, including free-hand (P-free), a commercial needle guide (P-com), and a novel needle guide (P-sha). The view inside a simulated vein was recorded during venipuncture.

Results

Thirty-five residents participated in this study. Posterior vein wall injuries occurred in 66% using P-free, 60% using P-com, and 0% using P-sha (p< 0.01). There was no significant difference in the incidence of posterior vein wall injuries between P-free and P-com.

Conclusions

Use of a shallow angle of approach needle guide resulted in a lower rate of posterior vein injuries during venipuncture of a simulated vein compared with other techniques using a steeper angle techniques.

Effect of ultrasound-guided central venous catheter insertion on the incidence of catheter-related bloodstream infections and mechanical complications

Background

Central venous catheters (CVCs) are necessary for critically ill patients, including those with hematological malignancies. However, CVC insertion is associated with inevitable risks for various adverse events. Whether ultrasound guidance decreases the risk of catheter-related infection remains unclear.

Methods

We observed 395 consecutive CVC insertions between April 2009 and January 2013 in our hematological oncology unit. Because the routine use of ultrasound guidance upon CVC insertion was adopted based on our hospital guidelines implemented after 2012, the research period was divided into before December 2011 (early term) and after January 2012 (late term).

Results

Underlying diseases included hematological malignancies and immunological disorders. In total, 235 and 160 cases were included in the early- and late term groups, respectively. The median insertion duration was 26 days (range, 2–126 days) and 18 days (range, 2–104 days) in the early- and late term groups, respectively. The internal jugular, subclavian, and femoral veins were the sites of 22.6, 40.2, and 25.7% of the insertions in the early term group and 32.3, 16.9, and 25.4% of the insertions in the late term group, respectively. The frequency of catheter-related bloodstream infection (CRBSI) was 1.98/1000 catheter days and 2.17/1000 catheter days in the early- and late term groups, respectively. In the subgroup analysis, the detected causative pathogens of CRBSI did not differ between the two term groups; gram-positive cocci, gram-positive bacilli, and gram-negative bacilli were the causative pathogens in 68.9, 11.5, and 14.8% of the cases in the early term group and in 68.2, 11.4, and 18.2% of the cases in the late term group, respectively. In the multivariate analysis to determine the risk of CRBSI, only age was detected as an independent contributing factor; the indwelling catheter duration was detected as a marginal factor. A significant reduction in mechanical complications was associated with the use of ultrasound guidance.

Conclusions

Ultrasound-guided CVC insertion did not decrease the incidence of CRBSI. The only identified risk factor for CRBSI was age in our cohort. However, we found that the introduction of ultrasound-guided insertion triggered an overall change in safety management with or without the physicians’ intent.

Recommendations on the Use of Ultrasound Guidance for Central and Peripheral Vascular Access in Adults: A Position Statement of the Society of Hospital Medicine

PREPROCEDURE

1)We recommend that providers should be familiar with the operation of their specific ultrasound machine prior to initiation of a vascular access procedure. 2)We recommend that providers should use a high-frequency linear transducer with a sterile sheath and sterile gel to perform vascular access procedures. 3)We recommend that providers should use two-dimensional ultrasound to evaluate for anatomical variations and absence of vascular thrombosis during preprocedural site selection. 4)We recommend that providers should evaluate the target blood vessel size and depth during preprocedural ultrasound evaluation.

TECHNIQUES

General Techniques 5) We recommend that providers should avoid using static ultrasound alone to mark the needle insertion site for vascular access procedures. 6)We recommend that providers should use real-time (dynamic), two-dimensional ultrasound guidance with a high-frequency linear transducer for central venous catheter (CVC) insertion, regardless of the provider's level of experience. 7)We suggest using either a transverse (short-axis) or longitudinal (long-axis) approach when performing real-time ultrasound-guided vascular access procedures. 8)We recommend that providers should visualize the needle tip and guidewire in the target vein prior to vessel dilatation. 9)To increase the success rate of ultrasound-guided vascular access procedures, we recommend that providers should utilize echogenic needles, plastic needle guides, and/or ultrasound beam steering when available. Central Venous Access Techniques 10) We recommend that providers should use a standardized procedure checklist that includes the use of real-time ultrasound guidance to reduce the risk of central line-associated bloodstream infection (CLABSI) from CVC insertion. 11)We recommend that providers should use real-time ultrasound guidance, combined with aseptic technique and maximal sterile barrier precautions, to reduce the incidence of infectious complications from CVC insertion. 12)We recommend that providers should use real-time ultrasound guidance for internal jugular vein catheterization, which reduces the risk of mechanical and infectious complications, the number of needle passes, and time to cannulation and increases overall procedure success rates. 13)We recommend that providers who routinely insert subclavian vein CVCs should use real-time ultrasound guidance, which has been shown to reduce the risk of mechanical complications and number of needle passes and increase overall procedure success rates compared with landmark-based techniques. 14)We recommend that providers should use real-time ultrasound guidance for femoral venous access, which has been shown to reduce the risk of arterial punctures and total procedure time and increase overall procedure success rates. Peripheral Venous Access Techniques 15) We recommend that providers should use real-time ultrasound guidance for the insertion of peripherally inserted central catheters (PICCs), which is associated with higher procedure success rates and may be more cost effective compared with landmark-based techniques. 16)We recommend that providers should use real-time ultrasound guidance for the placement of peripheral intravenous lines (PIV) in patients with difficult peripheral venous access to reduce the total procedure time, needle insertion attempts, and needle redirections. Ultrasound-guided PIV insertion is also an effective alternative to CVC insertion in patients with difficult venous access. 17)We suggest using real-time ultrasound guidance to reduce the risk of vascular, infectious, and neurological complications during PIV insertion, particularly in patients with difficult venous access. Arterial Access Techniques 18)We recommend that providers should use real-time ultrasound guidance for arterial access, which has been shown to increase first-pass success rates, reduce the time to cannulation, and reduce the risk of hematoma development compared with landmark-based techniques. 19)We recommend that providers should use real-time ultrasound guidance for femoral arterial access, which has been shown to increase first-pass success rates and reduce the risk of vascular complications. 20)We recommend that providers should use real-time ultrasound guidance for radial arterial access, which has been shown to increase first-pass success rates, reduce the time to successful cannulation, and reduce the risk of complications compared with landmark-based techniques.

POSTPROCEDURE

21) We recommend that post-procedure pneumothorax should be ruled out by the detection of bilateral lung sliding using a high-frequency linear transducer before and after insertion of internal jugular and subclavian vein CVCs. 22)We recommend that providers should use ultrasound with rapid infusion of agitated saline to visualize a right atrial swirl sign (RASS) for detecting catheter tip misplacement during CVC insertion. The use of RASS to detect the catheter tip may be considered an advanced skill that requires specific training and expertise.

TRAINING

23) To reduce the risk of mechanical and infectious complications, we recommend that novice providers should complete a systematic training program that includes a combination of simulation-based practice, supervised insertion on patients, and evaluation by an expert operator before attempting ultrasound-guided CVC insertion independently on patients. 24)We recommend that cognitive training in ultrasound-guided CVC insertion should include basic anatomy, ultrasound physics, ultrasound machine knobology, fundamentals of image acquisition and interpretation, detection and management of procedural complications, infection prevention strategies, and pathways to attain competency. 25)We recommend that trainees should demonstrate minimal competence before placing ultrasound-guided CVCs independently. A minimum number of CVC insertions may inform this determination, but a proctored assessment of competence is most important. 26)We recommend that didactic and hands-on training for trainees should coincide with anticipated times of increased performance of vascular access procedures. Refresher training sessions should be offered periodically. 27)We recommend that competency assessments should include formal evaluation of knowledge and technical skills using standardized assessment tools. 28)We recommend that competency assessments should evaluate for proficiency in the following knowledge and skills of CVC insertion: (a) Knowledge of the target vein anatomy, proper vessel identification, and recognition of anatomical variants; (b) Demonstration of CVC insertion with no technical errors based on a procedural checklist; (c) Recognition and management of acute complications, including emergency management of life-threatening complications; (d) Real-time needle tip tracking with ultrasound and cannulation on the first attempt in at least five consecutive simulation. 29)We recommend a periodic proficiency assessment of all operators should be conducted to ensure maintenance of competency.

Optical skill-assist device for ultrasound-guided vascular access: A preliminary simulation study

Ultrasound-guided central venous catheterization may cause lethal mechanical complications intraoperatively. We developed a novel device to prevent such complications. It works as a needle guide to supplement the operator's skill. We evaluated the utility of this device in terms of the success rate and visualization of the needle tip while penetrating the target vessel using a simulator.This study was approved by the local ethics committee. The new device - an optical skill-assist device - has a slit and a mirror in the center. The operator can see the needle's reflection in the mirror through the slit and can thus ensure that the needle is directed in line with the ultrasound beam. Participants were recruited by placing an advertisement for a hands-on seminar on ultrasound-guided vascular access. They received hands-on training on the in-plane approach for 2 hours. Pre-test and post-test without the device and an additional test using the device were performed to evaluate the proficiency of ultrasound-guided vascular access. An endoscope inserted into the simulated vessel was used to detect the precise location of the needle tip in the vessel.The primary outcomes were the success rate of the procedure. The secondary outcome was visualization of the needle tip while penetrating the simulated vessel. The chi-squared test was used for comparing the success rate and needle tip visualization between the different tests. P < .05 was considered to indicate significant differences.Forty-two participants were enrolled in this study. The success rate did not increase after the simulation training (P = .1). Using the optical skill-assist device, the rate improved to 100%. There was a significant difference in success rate between the pre-test and additional test using the optical skill-assist device (P = .003). Needle tip visualization significantly improved with the use of the optical skill-assist device compared to the pre-test (P < .001) and post-test (P = .001).Simulation training improved participants' skill for ultrasound-guided vascular access, but the improvement depended on each participant. However, further, improvement was achieved with the use of the optical skill-assist device.The optical skill-assist device is useful for supplementing the operator's skill for ultrasound-guided central venous catheterization.

Ultrasound-guided vascular access in critical illness

Over the past two decades, ultrasound (US) has become widely accepted to guide safe and accurate insertion of vascular devices in critically ill patients. We emphasize central venous catheter insertion, given its broad application in critically ill patients, but also review the use of US for accessing peripheral veins, arteries, the medullary canal, and vessels for institution of extracorporeal life support. To ensure procedural safety and high cannulation success rates we recommend using a systematic protocolized approach for US-guided vascular access in elective clinical situations. A standardized approach minimizes variability in clinical practice, provides a framework for education and training, facilitates implementation, and enables quality analysis. This review will address the state of US-guided vascular access, including current practice and future directions.

The Value of Needle-Guidance Technology in Ultrasound-Guided Percutaneous Procedures Performed by Radiology Residents: A Comparison of Freehand, In-Plane, Fixed-Angle, and Electromagnetic Needle Tracking Techniques

OBJECTIVES

Radiology residents typically learn ultrasound-guided procedures by performing supervised procedures on patients who may experience longer procedure times and higher complication rates. The purpose of this study was to determine if existing technologies, such as in-plane, fixed-angle guidance (IPFA) and electromagnetic needle tracking (ENT), can improve resident procedure time and accuracy.

METHODS

Radiology residents (18 total) were randomized to 1 of 3 ultrasound-guidance technique groups-freehand, IPFA, or ENT-and instructed to place a needle into 4 liver lesions in a humanoid phantom, each increasing in difficulty. For each lesion, residents were timed from skin puncture to needle placement, and the number of times the needle was pulled back and redirected (pullbacks) was recorded. Primary outcomes were total time and total number of pullbacks for all 4 lesions. Secondary outcomes were individual time and number of pullbacks for each lesion.

RESULTS

Compared to the freehand group, the IPFA and ENT groups demonstrated lower procedural time and number of pullbacks both in total and for each individual lesion. Differences in total time and total number of pullbacks were significant (P < .001), as were differences for lesion 3 (P = .002-.02) and lesion 4 (P < .001). Differences for lesions 1 and 2 were not statistically significant.

CONCLUSIONS

Radiology resident procedure time and procedure accuracy (as judged by number of pullbacks) are significantly improved by the use IPFA and ENT guidance technologies.

Evaluation of a Novel Out-of-Plane Needle Guide

OBJECTIVES

Most ultrasound-guided regional procedures use an in-plane approach. Out-of-plane approaches may be desirable in some situations but can be difficult because of an inability to visualize the needle until it intersects the plane of the ultrasonic beam. Here we present a novel out-of-plane needle guide, using a retreating depth stop, and compare its performance with unguided in-plane and out-of-plane techniques.

METHODS

First- and third-year medical students with no or minimal ultrasound experience were recruited for the study. After a brief training session on in-plane and out-of-plane needling techniques, as well as use of the retreating-stop needle guide, they attempted to place a needle as close as possible to a target embedded in porcine tissue. The total time to complete the procedure was measured. Accuracy was measured by a skilled sonographer, who identified the needle tip and measured the distance to the target. The data were tested for significance using an analysis of variance.

RESULTS

The mean total time spent differed significantly between groups (novel needle guide, 34 seconds; in-plane, 120 seconds; out-of-plane, 113 seconds; P = .021). Needle proximity was on average more accurate with the needle guide, although this difference was not statistically significant (novel needle guide, 8 mm; in-plane, 15 mm; out-of-plane, 14 mm; P = .289).

CONCLUSIONS

In relatively inexperienced sonographers, the retreating-stop needle guide reduced the procedure time compared with in-plane and out-of-plane techniques. No significant changes in needling accuracy were observed.

Real-time ultrasound-guided axillary vein cannulation in children: a randomised controlled trial

The axillary vein is a good site for ultrasound-guided central venous cannulation in terms of infection rate, patient comfort and its anatomical relationship with the clavicle and lungs. We compared real-time ultrasound-guided axillary vein cannulation with conventional infraclavicular landmark-guided subclavian vein cannulation in children. A total of 132 paediatric patients were randomly allocated to either ultrasound-guided axillary vein (axillary group) or landmark-guided subclavian vein (landmark group). The outcomes measured were success rate after two attempts, first-attempt success rate, time to cannulation and complication rate. The success rate after two attempts was 83% in the axillary group compared with 63% in the landmark group (odds ratio 2.85, 95%CI 1.25-6.48, p = 0.010). The first-attempt success rate was 46% for the axillary group and 40% for the landmark group (p = 0.274) and median time to cannulation was 156 s for the axillary group and 180 s for the landmark group (p = 0.286). There were no differences in complication rates between the two groups, although three episodes of subclavian artery puncture occurred in the landmark group (p = 0.08). We conclude that axillary vein cannulation using a real-time ultrasound-guided in-plane technique is useful and effective in paediatric patients.

Ultrasound-guided central venous catheter placement: a structured review and recommendations for clinical practice

The use of ultrasound (US) has been proposed to reduce the number of complications and to increase the safety and quality of central venous catheter (CVC) placement. In this review, we describe the rationale for the use of US during CVC placement, the basic principles of this technique, and the current evidence and existing guidelines for its use. In addition, we recommend a structured approach for US-guided central venous access for clinical practice. Static and real-time US can be used to visualize the anatomy and patency of the target vein in a short-axis and a long-axis view. US-guided needle advancement can be performed in an "out-of-plane" and an "in-plane" technique. There is clear evidence that US offers gains in safety and quality during CVC placement in the internal jugular vein. For the subclavian and femoral veins, US offers small gains in safety and quality. Based on the available evidence from clinical studies, several guidelines from medical societies strongly recommend the use of US for CVC placement in the internal jugular vein. Data from survey studies show that there is still a gap between the existing evidence and guidelines and the use of US in clinical practice. For clinical practice, we recommend a six-step systematic approach for US-guided central venous access that includes assessing the target vein (anatomy and vessel localization, vessel patency), using real-time US guidance for puncture of the vein, and confirming the correct needle, wire, and catheter position in the vein. To achieve the best skill level for CVC placement the knowledge from anatomic landmark techniques and the knowledge from US-guided CVC placement need to be combined and integrated.

Randomized controlled trials in central vascular access devices: A scoping review

BACKGROUND

Randomized controlled trials evaluate the effectiveness of interventions for central venous access devices, however, high complication rates remain. Scoping reviews map the available evidence and demonstrate evidence deficiencies to focus ongoing research priorities.

METHOD

A scoping review (January 2006-December 2015) of randomized controlled trials evaluating the effectiveness of interventions to improve central venous access device outcomes; including peripherally inserted central catheters, non-tunneled, tunneled and totally implanted venous access catheters. MeSH terms were used to undertake a systematic search with data extracted by two independent researchers, using a standardized data extraction form.

RESULTS

In total, 178 trials were included (78 non-tunneled [44%]; 40 peripherally inserted central catheters [22%]; 20 totally implanted [11%]; 12 tunneled [6%]; 6 non-specified [3%]; and 22 combined device trials [12%]). There were 119 trials (68%) involving adult participants only, with 18 (9%) pediatric and 20 (11%) neonatal trials. Insertion-related themes existed in 38% of trials (67 RCTs), 35 RCTs (20%) related to post-insertion patency, with fewer trials on infection prevention (15 RCTs, 8%), education (14RCTs, 8%), and dressing and securement (12 RCTs, 7%). There were 46 different study outcomes reported, with the most common being infection outcomes (161 outcomes; 37%), with divergent definitions used for catheter-related bloodstream and other infections.

CONCLUSION

More high quality randomized trials across central venous access device management are necessary, especially in dressing and securement and patency. These can be encouraged by having more studies with multidisciplinary team involvement and consumer engagement. Additionally, there were extensive gaps within population sub-groups, particularly in tunneled devices, and in pediatrics and neonates. Finally, outcome definitions need to be unified for results to be meaningful and comparable across studies.