Transesophageal Echocardiography for Verification of the Position of the Electrocardiographically-Placed Central Venous Catheter

A comparison between two radiological criteria for verifying tip location of central venous catheters

INTRODUCTION

Current guidelines recommend intraprocedural methods-such as Intra-Cavitary ECG (IC-ECG) and echocardiography-for verifying the location of the tip of central venous catheters. Nonetheless, there are clinical conditions which may require to verify tip location by less accurate methods such as Chest X-Ray (CXR). We have compared the feasibility and accuracy of two radiological methods for tip location-the Sweet Spot Criterion (SSC) and the Carina Criterion (CC)-using IC-ECG as reference.

METHODS

In this retrospective multicenter study, we reviewed the radiology databases of three hospitals, examining all CXRs performed on patients after insertion of Peripherally Inserted Central Catheters (PICCs), as long as the tip location had been successfully performed during the procedure by IC-ECG. Tip location was verified using SSC and CC, comparing the two methods in terms of feasibility and accuracy.

RESULTS

We reviewed the CXR of 1116 PICCs successfully inserted by IC-ECG. CC was not feasible in 0.5% (impossible visualization of the carina) and difficult in 1.5%; in 97.7% of cases, the position of the tip was adequate (1-5 cm below the carina), in 0.6% too high (<1 cm), in 1.2% too low (6-9 cm). On the other hand, because of unclear visualization of radiological landmarks, SSC was not feasible in 0.9% and difficult in 10.5%; though, according to SSC the tip location was always acceptable (in 94.2% the tip was in the middle of the spot, in 2.5% close to the superior border, and in 2.3% close to the inferior border); no tip was visualized outside of the spot.

CONCLUSION

CC and SSC were similar in terms of feasibility (99.5% vs 99.1%) and accuracy (98.1% vs 100%), though CC was subjectively perceived to be easier and more rapid to perform.

Applicability and feasibility of intraprocedural tip location of femorally inserted central catheters by transhepatic ultrasound visualization of the inferior vena cava in adult patients

BACKGROUND

The ideal intraprocedural method for tip location during insertion of femorally inserted central catheters (FICCs) is still a matter of debate. When the catheter tip is meant to be in the right atrium or in the supradiaphragmatic inferior vena cava (IVC), tip location by either intracavitary electrocardiography or transthoracic echocardiography may be accurate and easy to perform. When the catheter tip is planned to be placed in the subdiaphragmatic IVC, fluoroscopy-though inaccurate and unsafe-has been regarded as the only option for intraprocedural tip location.

METHODS

We have investigated prospectively the applicability and feasibility of transhepatic ultrasound as intraprocedural method for assessing the location of the catheter tip in the subdiaphragmatic tract of IVC, during FICC insertion.

RESULTS

We enrolled 169 consecutive patients undergoing FICC insertion by ultrasound guided puncture of the superficial femoral vein. In 165 out of 169 patients, the subdiaphragmatic IVC was visualized by the transhepatic ultrasound view. In all cases of IVC visualization, the catheter tip could be identified by ultrasound, either directly (direct evidence of the tip inside the vein) or indirectly (enhanced visualization of the tip after "bubble test"). There was no immediate or early complication, and very few late complications.

CONCLUSION

The intraprocedural method of tip location of FICCs by transhepatic ultrasound was applicable in 97.6% of cases and feasible in 100%. When the position of the catheter tip is planned to be in the subdiaphragmatic IVC, this method of tip location is accurate, safe, and inexpensive, and should be considered as an alternative to fluoroscopy.

A randomised trial of intracavitary electrocardiography versus surface landmark measurement for central venous access device placement

BACKGROUND

Malpositioned central venous access devices (CVADs) can lead to significant patient injury including central vein thrombosis and dysrhythmias. Intra-cavitary electrocardiography (IC ECG) has been recommended by peak professional bodies as an accurate alternative for bedside CVAD insertion, to reduce risk of malposition and allowing immediate use of the device. Our objective was to compare the effect of IC ECG on CVAD malposition compared to traditional institutional practice for CVAD placement.

METHODS

Randomised controlled trial of IC ECG CVAD insertion verses traditional CVAD insertion (surface landmark measurement with post insertion x ray). Patient recruitment was from December 2016 to July 2018. The setting was a 900-bed tertiary referral hospital based in South Western Sydney, Australia. Three hundred and forty-four adult patients requiring CVAD insertion for intravenous therapy, were enrolled and randomly allocated (1:1 ratio) to either IC-ECG (n = 172) or traditional (n = 172) CVAD insertion. Our primary outcome of interest was the rate of catheters not requiring repositioning after insertion (ready for use). Secondary outcomes were comparison of procedure time and cost.

RESULTS

Of the 172 patients allocated to the IC ECG method, 170 (99%) were ready for use immediately compared to 139 of the 172 (81%) in the traditional insertion group (difference, 95% confidence interval (CI): 18%, 11.9-24.1%). The total procedure time was mean 15 min (SD 8 min) for IC ECG and mean 36 min (SD 17 min) for traditional CVAD insertion (difference-19.9 min (95% CI-14.6 to -34.4). IC ECG guided CVAD insertion had a cost reduction of AUD $62.00 per procedure.

CONCLUSIONS

Using IC-ECG resulted in nearly no requirement for post-insertion repositioning of CVADs resulting in savings in time and cost and virtually eliminating the need for radiographic confirmation.

TRIAL REGISTRATION

This trial is registered at the Australian New Zealand Clinical Trials Registry (http://www.anzctr.org.au). The registration number is ACTRN12620000919910.

The intracavitary ECG method for tip location of ultrasound-guided centrally inserted central catheter in neonates

BACKGROUND

The correct position of the tip of a central venous access device is important in all patients, and especially in neonates. The traditional method of tip location (approximated intra-procedural length estimation + post procedural chest X-ray) is currently considered inaccurate and not cost-effective by most recent guidelines, which recommend the adoption of tip location by intracavitary electrocardiography (IC-ECG) whenever possible.

METHODS

This study prospectively investigated the applicability, the feasibility, the accuracy, and the safety IC-ECG for tip location in neonates requiring insertion of ultrasound-guided centrally inserted central venous catheters (CICCs) with caliber 3Fr or more. All catheter tip locations were verified using simultaneously both IC-ECG and ultrasound-based tip location, using the Neo-ECHOTIP protocol.

RESULTS

A total of 105 neonates were enrolled. The applicability of IC-ECG was 100% since a P wave was evident on the surface ECG of all neonates recruited for the study. The feasibility was also 100% since an increase of the P-wave was detected in all cases. The accuracy was also 100%, since a perfect match between IC-ECG based tip location and ultrasound-based tip location was found. There were no adverse events directly or indirectly related to the IC-ECG technique; no arrhythmias occurred.

CONCLUSIONS

When applied to ultrasound guided CICCs, tip location by IC-ECG is applicable and feasible in neonates, and it is safe and accurate.

Assessment of the Tip Position of Central Venous Catheters Inserted Using Peres' Height Formula

OBJECTIVES

The tip of a central venous catheter (CVC) should be positioned in the proximity of the cavo-atrial junction (CAJ) where the lower third of the superior vena cava (SVC) and the upper right atrium (RA) are located to prevent life-threatening complications. This study aimed to determine the accuracy of Peres' height formula in predicting the correct insertion depth of CVC.  Methods: A total of 332 patients were enrolled in this prospective observational study. All CVCs were inserted using Peres' formula. The 'correct' tip position of CVC was the placement of the CVC tip 1 cm above and 1 cm below the carina in CXR. Rates of correct placements for each side and site of catheter insertions, gender, and body mass index (BMI) differences were evaluated.

RESULTS

The correct placement rate of all catheters was 74.4%. There were statistically significant correlations between the correct placement of right-sided jugular and subclavian catheters (p<0.001) and left-sided jugular and subclavian catheters (p=0.014). There was a statistically significant difference in male patients (p=0.047). Higher BMI resulted in a lower rate of correct placement with no statistically significant difference (p=0.457).

CONCLUSIONS

Peres' formula can be easily used to determine the correct position of CVC tips with a success rate in the Turkish population. However, practitioners should be aware of the low accuracy rate of Peres' formula in female patients (68.5%) and patients with BMI over 35 kg/m² (62.5%).

Safety of bedside placement of tunneled dialysis catheter in COVID-19 patients

COVID-19 patients admitted to the ICU have high incidence of AKI requiring prolonged renal replacement therapy and often necessitate the placement of a tunneled dialysis catheter (TDC). We describe our experience with two cases of COVID-19 patients who underwent successful bedside placement of TDC under ultrasound guidance using anatomical landmarks without fluoroscopy guidance. Tunneled dialysis catheter placement under direct fluoroscopy remains the standard of care; but in well selected patients, placement of tunneled dialysis catheter at the bedside using anatomic landmarks without fluoroscopy can be safely and successfully performed without compromising the quality of care and avoid transfer of COVID-19 infected patients outside the ICU.

Intracavitary electrocardiography for tip location during central venous catheterization: A narrative review of 70 years of clinical studies

Intracavitary electrocardiography is an accurate and non-invasive method for central venous access tip location. Using the catheter as a traveling intracavitary electrode, intracavitary electrocardiography is based on the increase in the detected amplitude of the P wave while approaching the cavoatrial junction. Despite having been adopted diffusely in clinical practice only in the last years, this method is not novel. In fact, it has first been described in the late 40s, during electrophysiological studies. After a long period of quiescence, it is in the last two decades of the XX century that intracavitary electrocardiography became popular as an effective mean of central venous catheters tip location. But the golden age of this technique began with the new millennium, as documented by high-quality studies in this period. In fact, in those years, intracavitary electrocardiography has been studied broadly, and important achievements in terms of comprehension of the technique, accuracy, and feasibility of the method in different populations and conditions (i.e. pediatrics, renal patients, atrial fibrillation) have been gained. In this review, we describe the technique, its history, and its current perspectives.

[Ultrasound visualization of the guidewire and positioning of the central venous catheter : A prospective observational study]

BACKGROUND

After insertion of a central venous catheter (CVC) the catheter position must be controlled and a pneumothorax ruled out.

OBJECTIVE

The aim was to examine whether the use of two standard acoustic windows known from emergency sonography examination techniques is feasible to 1) verify the correct intravenous localization and direction of the guidewire before final CVC insertion and 2) correctly predict the required CVC length for positioning of the catheter tip in the lower third of the superior vena cava.

MATERIAL AND METHODS

This single center prospective observational study included adult patients (age ≥18 years) with an indication for CVC insertion after institutional ethics approval was obtained. Puncture sites were restricted to bilateral internal jugular and subclavian veins and except for duplicate examinations no further exclusion criteria were defined. After vessel puncture and insertion of the guidewire, the vena cava was displayed by an additional ultrasound examiner (sector scanner 1.5-3.6 MHz) using the transhepatic or subcostal acoustic window to localize the guidewire. For positioning of the CVC tip, the required catheter length in relation to the cavoatrial junction was measured using the guidewire marks during slow retraction and consecutive disappearance of the J‑shaped guidewire tip from each acoustic window. From the resulting insertion length of the guidewire 4 cm was subtracted for the transhepatic and 2 cm for the subcostal window under the assumption that this length correlates to the distance from the cavoatrial junction. The CVC was finally inserted and a chest radiograph was performed for radiological verification of the CVC position.

RESULTS

Of 100 included patients, 94 could finally be analyzed. The guidewire could be identified in the vena cava in 91 patients (97%) within a time period of 2.2 ± 1.9 min. In three patients, the wire could not be visualized, although two catheters had the correct position, while one catheter was incorrectly positioned in the opposite axillary vein. In the second study part, positioning of the CVC was evaluated in 44 of the 94 patients. In 5 of these 44 patients, the correct direction and disappearance of the guidewire from the acoustic window could also be reliably visualized; however, with the left subclavian vein as the puncture site, the respective catheters were up to 6 cm too short for correct positioning. Thus, these 5 patients were excluded from this analysis. In the remaining 39 patients, the position of the CVC tip was optimally located in the lower third of the superior vena cava according to the chest radiograph in 20 patients (51%), while it was relatively too high in 5 patients (13%) and too low (entrance of the right atrium) in 9 patients. In the other 5 patients, disappearance of the guidewire from the acoustic window was not definitely detectable.

CONCLUSION

The presented intraprocedural ultrasound-based method using two standard acoustic windows is reliable for verification of the correct intravenous location and direction of the guidewire even before dilatation of the vessel puncture site for insertion of the catheter. Furthermore, the method allows the clinically acceptable measurement of the required length for catheter positioning. A chest radiograph can be waived provided the ultrasound examination (identification of the guidewire and exclusion of puncture-related complications such as pneumothorax) is unambiguous.

Reliability of cutaneous landmarks for the catheter length assessment during peripherally inserted central catheter insertion: A retrospective observational study

Introduction:

Peripherally inserted central catheters are very common devices for short, medium and long-term therapies. Their performance is strictly dependent on the correct tip location, at the junction between the upper caval vein and the right atrium. It is very important to obtain an estimated measure of the catheter, in order to reach the cavo-atrial junction and optimize the catheter length. Estimated measures are often obtained using cutaneous landmarks.

Objective:

Evaluate the reliability of cutaneous landmark-based length estimation during catheter insertion. Identify any patient’s related factors that may affect cutaneous landmarks reliability.

Methods:

We used two distinct techniques and collected data about cutaneous landmark-based length estimation, electrocardiographic guided intravascular length, age, weight and height. We studied the reliability of possible correcting factors, balancing the error average by regression models, and we found and tested two different models of prediction.

Results:

A total number of 519 patients were studied. The average bias, between the two studied length assessment by cutaneous landmarks and electrocardiographic guided catheter length, were 3.77 ± 2.44 cm and 3.28 ± 2.57 cm, respectively. The analysed prediction models (deviance explained 43.5%, Akaike information criterion = 1313.67% and 43.4%, Akaike information criterion = 1313.92), fitted on the validation set, showed a root mean square error of 3.07 and 3.06.

Conclusion:

Landmark-based length estimation for preventive catheter length assessment seems to be unreliable, when associated with post-procedural tip location. They are useful for distal trimming catheters to optimize the ‘out of skin’ portion when associated with electrocardiographic tip location. Models identified for balancing bias are probably not useful.

Guide wire electrode versus liquid electrode for intravascular electrocardiography-guided central venous catheterization in adults: A systematic review and meta-analysis

AIM

To assess the effectiveness and safety of guide wire electrode versus liquid electrode for intravascular electrocardiography-guided central venous catheter placement in adults.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

We searched the main electronic databases (Cochrane Library, the Joanna Briggs Institute Library, Embase, PubMed, CINAHL, China National Knowledge Infrastructure, and Wanfang) with articles published from inception up to March 2018. References of important articles were also screened for relevant studies. We used a structured search strategy and did not apply any search limitations.

REVIEW METHODS

Randomized, controlled trials, quasi-experimental studies or studies using a within-subject design, evaluating guide wire electrode versus liquid electrode for intravascular electrocardiography-guided central venous catheter placement in adults, were eligible for inclusion. Risk of bias assessment was performed using the Cochrane Collaboration's tool and meta-analysis was performed using RevMan 5.3.

RESULTS

In total, six studies with a total of 2176 participants were included. Meta-analysis showed that there was no statistically significant difference in accuracy of tip location placement between guide wire and liquid electrodes. Use of guide wire electrode had a higher risk of complications which were transient and there were an insufficient number of studies using the same parameters to evaluate intravascular electrocardiography signal quality.

CONCLUSION

Due to the small number and low quality of identified studies, it is difficult to draw definitive conclusions on the relative effectiveness and safety of guide wire versus liquid electrodes for the placement of central venous catheters in adults. More well-designed studies are needed in the future.

A comparative study of safety and efficacy of ultrasound-guided infra-clavicular axillary vein cannulation versus ultrasound-guided internal jugular vein cannulation in adult cardiac surgical patients

Background:

Ultrasound (US)-guided internal jugular vein (IJV) cannulation is a widely accepted standard procedure. The axillary vein (AV) in comparison to the subclavian vein is easily visualized, but its cannulation is not extensively studied in cardiac patients.

Aims:

This study is an attempt to study the efficacy of real-time US-guided axillary venous cannulation as a safe alternative for the time-tested US-guided IJV cannulation.

Design:

This is a prospective randomized controlled study.

Materials and Methods:

A total of 100 adult patients scheduled for cardiac surgery were divided equally in Group A-US-guided IJV cannulation, and Group B-US-guided axillary venous cannulation. Under local anesthesia and real-time US guidance the IJV or AV was secured. The access time, guidewire time, and procedure time were noted. Furthermore, the number of needle attempts, malposition, change of site, and complications were noted.

Results:

The data were analyzed for 49 patients in Group A and 48 patients in the Group B due to exclusions. The access time and the guidewire time were comparable in both groups. The first attempt needle puncture was successful for the IJV group in 98% of patients in comparison to 95% of patients in Group B. Guidewire was passed in the first attempt in 94% in Group A and 89% in the Group B. Except for arterial puncture in one case in group A, the complications were insignificant in both groups.

Conclusion:

The study shows that the US-guided AV cannulation may serve as an effective alternative to the IJV cannulation in cardiac surgery.

A modified intracavitary electrocardiographic method for detecting the location of the tip of central venous catheters in atrial fibrillation patients

Introduction:

The intracavitary electrocardiographic method is recommended for assessing the location of the tip of central venous catheter when there is an identifiable P wave. Previous reports suggested that intracavitary electrocardiographic method might also be applied to patients with atrial fibrillation, considering the so-called f waves as a surrogate of the P wave.

Methods:

We studied 18 atrial fibrillation patients requiring simultaneously a central venous catheter and a trans-esophageal echocardiography. An intracavitary electrocardiographic trace was recorded with the catheter tip in three different positions defined by trans-esophageal echocardiography imaging: in the superior vena cava, 2 cm above the cavo-atrial junction; at the cavo-atrial junction; and in the right atrium, 2 cm below the cavo-atrial junction. Three different criteria of measurement of the f wave pattern in the TQ tract were used: the mean height of f waves (method A); the height of the highest f wave (method B); the difference between the highest positive peak and the lowest negative peak (method C).

Results:

There were no complications. With the tip placed at the cavo-atrial junction, the mean value of the f waves was significantly higher than in the other two positions. All three methods were effective in discriminating the tip position at the cavo-atrial junction, though method B proved to be the most accurate.

Conclusion:

A modified intracavitary electrocardiographic technique can be safely used for detecting the location of the tip of central venous catheters in atrial fibrillation patients: the highest activity of the f waves is an accurate indicator of the location of the tip at the cavo-atrial junction.

Transoesophageal echocardiographic evaluation of central venous catheter positioning using Peres' formula or a radiological landmark-based approach: a prospective randomized single-centre study

BACKGROUND

The lower superior vena cava (SVC), near its junction with the right atrium (RA), is considered the ideal location for the central venous catheter tip to ensure proper function and prevent injuries. We determined catheter insertion depth with a new formula using the sternoclavicular joint and the carina as radiological landmarks, with a 1.5 cm safety margin. The accuracy of tip positioning with the radiological landmark-based technique (R) and Peres' formula (P) was compared using transoesophageal echocardiography.

METHODS

Real-time ultrasound-guided central venous catheter insertion was done through the right internal jugular or subclavian vein. Patients were randomly assigned to either the P group (n=93) or the R group (n=95). Optimal catheter tip position was considered to be within 2 cm above and 1 cm below the RA-SVC junction. Catheter tip position, abutment, angle to the vascular wall, and flow stream were evaluated on a bicaval view.

RESULTS

The distance from the skin insertion point to the RA-SVC junction and determined depth of catheter insertion were more strongly correlated in the R group [17.4 (1.2) and 16.7 (1.5) cm; r=0.821, P<0.001] than in the P group [17.3 (1.2) and 16.4 (1.1) cm; r=0.517, P<0.001], with z=3.96 (P<0.001). More tips were correctly positioned in the R group than in the P group (74 vs 93%, P=0.001). Abutment, tip angle to the lateral wall >40°, and disrupted flow stream were comparable.

CONCLUSIONS

Catheter tip position was more accurate with a radiological landmark-based technique than with Peres' formula.

CLINICAL TRIAL REGISTRATION

Clinical Trial Registry of Korea: https://cris.nih.go.kr/cris/index.jsp KCT0001937.

The "rapid atrial swirl sign" for assessing central venous catheters: Performance by medical residents after limited training

Rationale

Central venous catheter (CVC) placement is a standard procedure in critical care. Ultrasound guidance during placement is recommended by current guidelines, but there is no consensus on the best method for evaluating the correct CVC tip position. Recently, the “rapid atrial swirl sign” (RASS) has been investigated in a limited number of studies.

Objectives

We performed a prospective diagnostic accuracy study of focused echocardiography for the evaluation of CVC tip position in our medical ICU and IMC units.

Methods

We performed a prospective diagnostic accuracy study in 100 patients admitted to the Intensive Care Unit and Intermediate Care Unit at our center. The first 10 subjects were assessed by one staff physician investigator (reference cohort), the remaining 90 patients by different residents (test cohort). All patients received a post-procedural chest radiograph (CXR) as gold standard. CVC placement was assessed with focused echocardiography performed by residents after a short training session. A rapid opacification of the right atrium (RASS) after injection of 10 mL of normal saline was regarded as “positive”, flush after more than two seconds was defined as “delayed”, no flush was a “negative” test result.

Measurements and main results

Overall sensitivity of the RASS was 100% (95% CI 73.54–100%), specificity was 94.32% (CI 87.24–98.13%). Positive and negative predictive values were 70.59% (CI 44.04–89.09%) and 100% (CI 95.65–100%), respectively. Median time for echocardiographic testing was 5 minutes (1–28) in the whole cohort, CXRs were available after 49.5 minutes (13–254). Interrater agreement of the RASS was 0.77 (Cohen’s kappa), Measurement of CVC tip position was not different between two observers. Test characteristics were similar among differently experienced residents.

Conclusions

Presence of the RASS by focused echocardiography showed excellent sensitivity and specificity and was equally performed by residents after minimal training. In patients with a positive RASS, routine CXR can be safely omitted, reducing time, costs and radiation exposure. A negative RASS should lead to a search for misplaced catheters.

Clinical trial registration

The study was registered with www.clinicaltrials.gov (NCT02661607).

Electrocardiogram-guided Technique: An Alternative Method for Confirming Central Venous Catheter Tip Placement

Background

The current standard followed for assessing central venous catheter (CVC) tip placement location is through radiological confirmation using chest X-ray (CXR). Placement of CVCs under electrocardiogram (ECG) guidance may save cost and time compared to CXR.

Objective

The objective of this study is to compare the accurate placement of the CVC tip using anatomical landmark technique with ECG-guided technique. Another objective is to compare CVC placement time and postprocedural complications between the two techniques.

Methods and Materials

A total of 144 adult individuals, who were critically ill and required CVC placement in the Emergency Department, were included for the study. Study duration was 6 months. Anatomical landmark and ECG-guided groups were assigned 72 participants each. Analyses were performed using t and Chi square-tests.

Results

It was observed that 13 (18%) in the landmark technique were malpositioned as compared to none in the ECG-guided technique (P = 0.000). The landmark group had 22 (30.6%) participants with arrhythmias during the procedure, compared to none in the ECG-guided group (P = 0.000). The landmark group revealed that 30 (41.7%) of the CVC were overinserted and required immediate repositioning, compared to none in the ECG-guided group (P = 0.000).

Conclusion

ECG-guided technique was found to be more accurate for CVC tip placement than the anatomical landmark technique. Furthermore, the ECG-guided technique was more time-effective and had less complications than the anatomical landmark technique. Hence, ECG-guided CVC placement is relatively accurate, efficient, and safe and can be considered as an alternative method to conventional radiography for confirmation of CVC tip placement.

Utilization of Thoracic Ultrasound for Confirmation of Central Venous Catheter Placement and Exclusion of Pneumothorax: A Novel Technique in Real-Time Application

AIM

To evaluate the safety and utility of ultrasonography as a tool to confirm central venous catheter (CVC) position and to exclude insertion-related pneumothorax in place of chest radiography (CXR) in a tertiary medical intensive care unit (ICU).

METHODS

We randomized 60 consecutive medical ICU patients to conventional or ultrasound groups for CVC placement. Both groups had CVCs inserted under ultrasound guidance. The intervention group underwent real-time transthoracic echocardiography to assist in catheter positioning and chest ultrasonography for exclusion of pneumothorax. Our primary end point was reduction in CXR use. The secondary end point was time elapsed from the end of procedure to the availability of CVC for use. χ² test was used to compare the 2 groups for the primary end point. T test was used to compare the 2 groups for the secondary end point.

RESULTS

Thirty patients were randomized to the conventional group and 30 were randomized to the ultrasound group. One patient was excluded in the control group since the procedure needed to be aborted. Patient characteristics were well matched for age, body mass index, and acute physiologic assessment and chronic health evaluation (APACHE III) scores. There was a 56.7% ( P < .0001) reduction in CXR use in the ultrasound arm. Mean time to use was 53.6 minutes in the control group and 25 minutes in the ultrasound arm ( P = .0015). Mean time required to complete the procedure was 27.7 minutes in the control group and 24.1 minutes in the ultrasound group ( P = .2053). No pneumothorax was detected in either arm.

CONCLUSION

Ultrasound-guided CVC placement and positioning with a minor modification in technique reduced the use of bedside CXR and reduced the time to use of the CVC.

Biodegradable fiducial markers for X-ray imaging – soft tissue integration and biocompatibility

This study aims at investigation of material for innovative fiducial markers for soft tissue in X-ray based medical imaging. NH₃ plasma modified P[LAcoCL] combined with BaSO₄ and hydroxyapatite as radio-opaque fillers appears to be a promising material systems for this application.

Location of the Central Venous Catheter Tip With Bedside Ultrasound in Young Children: Can We Eliminate the Need for Chest Radiography?

OBJECTIVE

To compare the use of bedside ultrasound and chest radiography to verify central venous catheter tip positioning.

DESIGN

Prospective observational study.

SETTING

PICU of a university hospital.

PATIENTS

Patients aged 0-14 who required a central venous catheter.

INTERVENTION

None.

MEASUREMENTS AND MAIN RESULTS

Central venous catheter tip location was confirmed by ultrasound and chest radiography. Central venous catheters were classified as intra-atrial or extra-atrial according to their positions in relation to the cavoatrial junction. Central venous catheters located outside the vena cava were considered malpositioned. The distance between the catheter tip and the cavoatrial junction was measured. The time elapsed from image capture to interpretation was recorded. Fifty-one central venous catheters in 40 patients were analyzed. Chest radiography and ultrasound results agreed 94% of the time (κ coefficient, 0.638; p < 0.001) in determining intra-atrial and extra-atrial locations and 92% of the time in determining the diagnosis of central venous catheter malposition (κ coefficient, 0.670; p < 0.001). Chest radiography indicated a greater distance between the central venous catheter tip and the cavoatrial junction than measured by ultrasound, with a mean difference of 0.38 cm (95% CI, +0.27, +0.48 cm). Three central venous catheters were classified as extra-atrial by chest radiography but as intra-atrial by ultrasound. To locate the central venous catheter tip, ultrasound required less time than chest radiography (22.96 min [20.43 min] vs 2.23 min [1.06 min]; p < 0.001).

CONCLUSIONS

Bedside ultrasound showed a good agreement with chest radiography in detecting central venous catheter tip location and revealing incorrect positions. Ultrasound could be a preferable method for routine verification of central venous catheter tip and can contribute to increased patient safety.

Peroperative Electrocardiographic Control of Catheter Tip Position during Implantation of Femoral Venous Ports

Purpose

Electrocardiographic (ECG) guidance has been shown to be as effective than fluoroscopy to position the tip of central venous devices close to the superior vena cava (SVC)–right atrium (RA) junction. When SVC access is contraindicated, a femoral access may be used. The aim of this prospective study is to evaluate the effectiveness of ECG guidance to position the tip of femoral ports at inferior vena cava (IVC)–RA junction.

Methods

Inclusion criterion was the need for femoral port implantation. After insertion of the dilator in the femoral vein, the catheter with the guide wire inside was introduced and the ECG signal collected at the tip of the guide (Celsite™ ECG, B. Braun, Germany) or via saline injected in the catheter (Nautilus™, Perouse, France). Fluoroscopy was performed at each change of the P-wave from IVC to RA. A final X-ray was performed after withdrawing the catheter 2 cm below the first P-wave change.

Results

A total of 18 patients were included between December 2011 and June 2013. The P-wave was most often negative in IVC, biphasic when the catheter entered RA and giant and positive at the top of RA. When the catheter was withdraw 2 cm below the first biphasic P-wave the tip was just below the IVC–RA junction in 17 patients. In one patient P-wave changes were not significant and the final position was adjusted under fluoroscopy.

Conclusions

ECG guidance is effective to assess catheter tip position during femoral port placement and avoids the need for radiological methods.

The supraclavicular fossa ultrasound view for central venous catheter placement and catheter change over guidewire

The supraclavicular fossa ultrasound view can be useful for central venous catheter (CVC) placement. Venipuncture of the internal jugular veins (IJV) or subclavian veins is performed with a micro-convex ultrasound probe, using a neonatal abdominal preset with a probe frequency of 10 Mhz at a depth of 10-12 cm. Following insertion of the guidewire into the vein, the probe is shifted to the right supraclavicular fossa to obtain a view of the superior vena cava (SVC), right pulmonary artery and ascending aorta. Under real-time ultrasound view, the guidewire and its J-tip is visualized and pushed forward to the lower SVC. Insertion depth is read from guidewire marks using central venous catheter. CVC is then inserted following skin and venous dilation. The supraclavicular fossa view is most suitable for right IJV CVC insertion. If other insertion sites are chosen the right supraclavicular fossa should be within the sterile field. Scanning of the IJVs, brachiocephalic veins and SVC can reveal significant thrombosis before venipuncture. Misplaced CVCs can be corrected with a change over guidewire technique under real-time ultrasound guidance. In conjunction with a diagnostic lung ultrasound scan, this technique has a potential to replace chest radiograph for confirmation of CVC tip position and exclusion of pneumothorax. Moreover, this view is of advantage in patients with a non-p-wave cardiac rhythm were an intra-cardiac electrocardiography (ECG) is not feasible for CVC tip position confirmation. Limitations of the method are lack of availability of a micro-convex probe and the need for training.

Verification of correct central venous catheter placement in the emergency department: comparison between ultrasonography and chest radiography

In 210 consecutive patients undergoing emergency central venous catheterization, we studied whether an ultrasonography examination performed at the bedside by an emergency physician can be an alternative method to chest X-ray study to verify the correct central venous catheter placement, and to identify mechanical complications. A prospective, blinded, observational study was performed, from January 2009 to December 2011, in the emergency department of a university-affiliated teaching hospital. Ultrasonography interpretation was completed during image acquisition; ultrasound scan was performed in 5 ± 3 min, whereas the time interval between chest radiograph request and its final interpretation was 65 ± 74 min p < 0.0001. We found a high concordance between the two diagnostic modalities in the identification of catheter position (Kappa = 82 %, p < 0.0001), and their ability to identify a possible wrong position showed a high correlation (Pearson's r = 0.76 %, p < 0.0001) with a sensitivity of 94 %, a specificity of 89 % for ultrasonography. Regarding the mechanical complications, three iatrogenic pneumothoraces occurred, all were correctly identified by ultrasonography and confirmed by chest radiography (sensitivity 100 %). Our study showed a high correlation between these two modalities to identify possible malpositioning of a catheter resulting from cannulation of central veins, and its complications. The less time required to perform ultrasonography allows earlier use of the catheter for the administration of acute therapies that can be life-saving for the critically ill patients.

The intracavitary ECG method for positioning the tip of central venous catheters: results of an Italian multicenter study

PURPOSE

The aim of this multicenter study was to assess the feasibility, safety, and accuracy of the intracavitary ECG method for real-time positioning of the tip of different types of central venous catheters.

METHODS

A total of 1444 catheter insertions in adult patients were studied in eight Italian centers (539 ports, 245 PICCs, 325 tunneled CVCs, 335 non-tunneled CVCs). Patients with no visible P wave at the standard baseline ECG were excluded. Depending on the type of catheter and its purpose, the target was to position the tip either (a) at the cavo-atrial junction, or (b) in the lower third of the superior vena cava, or (c) in the upper part of the atrium. The final position was verified by a post-procedural chest x-ray.

RESULTS

The method was feasible in 99.3% of all cases. There were no complications potentially related to the method itself. At the final x-ray control, 83% of all tips were positioned exactly at the target; 12.4% were positioned within 1-2 cm from the target, but still in a correct central position; only 3.8% were malpositioned. The mismatch between intra-procedural ECG method and post-procedural x-ray was significantly lower when the x-ray was taken in supine position.

CONCLUSIONS

Our multicenter study confirms that the intracavitary ECG method for real time verification of tip position is accurate, safe, feasible in all adult patients and applicable to any type of short-term or long-term central venous access device.

Bedside ultrasound can safely eliminate the need for chest radiographs after central venous catheter placement: CVC sono in the surgical ICU (SICU)

BACKGROUND

Real-time ultrasound guidance of central venous catheter (CVC)/peripherally inserted central catheter (PICC) insertion improves safety and efficacy. We hypothesized that a more robust ultrasound surveillance technique incorporating thoracic, vascular, and cardiac views-the CVC sono-would avoid the need for chest radiography to realize cost and efficiency gains.

METHODS

We conducted a prospective data collection in a high-volume, urban, academic SICU. A single surgical intensivist, blinded to the results of chest radiography, performed all CVC sonos post-insertion. Catheter malposition was defined as location extrinsic to the superior vena cava and determined by a board-certified radiologist on chest radiography. CVC sono consisted of (1) mechanical complications screen (hemo-, pneumothorax), (2) intravenous tip screen, (3) intracardiac tip screen. The result of CVC sono was compared with chest radiography.

RESULTS

CVC sono evaluated 83 catheters (42 CVCs and 41 PICCs) and was considered technically adequate in 59 (71%). Incomplete studies were significantly more common in those with chest tubes (P = 0.02), but not in those with cervical collars (P = 0.07), an open abdomen (P = 0.28), or BMI > 40 (P = 0.33). Mean CVC sono time was 10.8 min, compared with chest radiography of 75.3 min (P < 0.001). No hemo-pneumothoraces developed. Presence of multiple indwelling central catheters (>1 CVC) trended for inaccurate CVC sono for catheter malposition (accuracy: 79% versus 93%, P = 0.11).

CONCLUSION

A novel ultrasound technique, CVC sono eliminated the need for chest radiography in most patients after CVC/PICC insertion, saving time and money. Those with multiple indwelling central catheters may still require post-insertion conventional chest radiography.