Update on Insertion and Complications of Central Venous Catheters for Hemodialysis

Malposition of Central Venous Catheter into Coronary Sinus throughout the Persistent Left Superior Vena Cava and Other Complications Related to Catheterization

This case concentrates on the persistent left superior vena cava (PLSVC), a rare vascular anomaly which contributes to central venous catheter (CVC) misplacement. A 72-year-old woman with renal insufficiency presented to the hospital with recurrent bleeding from her permanent CVC device placed in the right common jugular vein. An initial attempt to replace the device was unsuccessful, necessitating the placement of a secondary catheter in the left jugular vein. Shortly after the procedure, the patient developed swelling of the face and neck. Further diagnostic imaging, including a chest radiograph and computed tomography (CT), revealed CVC misplacement in the PLSVC and coronary sinus, thrombosis of the common jugular vein, and a posterior mediastinal hematoma. Conservative therapy of the mediastinal hematoma was implemented and proved effective in this case. A temporary CVC was inserted into the left femoral vein. Two months later, the catheter underwent further dysfunction and a decision was made to place a long-term permanent CVC via the right femoral vein. The patient is currently awaiting an arteriovenous fistula for dialysis use. This case emphasizes the importance of radiological techniques for CVC procedural placement, as well as the detection of congenital abnormalities. Providers regularly placing CVCs should have an in-depth knowledge of the possible complications and potential anatomical variations, especially as seen in high-risk patients.

The Tunnelled Atrial Catheter: A Promising Solution for Vascular Capital Depletion in Dialysis despite Associated Thrombi

Introduction

Longer survival in dialysis led to a higher incidence of vascular access complications and failure. With the limited access to kidney transplantation programs and peritoneal dialysis, exhaustion of vascular access for hemodialysis is an increasingly common situation. Among the available options, atrial tunneled dialysis catheter (ATDC) has been reported as an effective vascular access in this population. Methodology. We report the experiences of two nephrology centers in Tunis with ATDC as an ultimate vascular access for dialysis. Case Reports. Two patients with exhausted vasculature underwent ATDC insertion in 2020 and 2022, respectively, as a vascular access of last resort. Both patients underwent CRBI, which resolved with favorable outcomes. One case was complicated by post-operative thrombosis and was successfully treated with thrombolysis. Both patients are currently on dialysis via their ATDC with a catheter patency of 29 months.

Conclusion

ATDC is a life-saving and safe vascular access in cases of depleted vasculature. Little more than 50 cases have been reported in the literature during the last 30 years. As the frequency of vasculature exhaustion is expected to increase, preservation of veinous access in patients at risk of chronic kidney disease have never been more crucial.

The clinical journey and healthcare resources required for dialysis access of end-stage kidney disease patients during their first year of hemodialysis

BACKGROUND

Creation and maintenance of dialysis vascular access (VA) is a major component of healthcare resource utilization and cost for patients newly started on hemodialysis (HD). Different VA format arises due to patient acceptance of anticipatory care versus late preparation, and clinical characteristics. This study reviews the clinical journey and resource utilization required for different VA formats in the first year of HD.

METHOD

Data of patients newly commenced on HD between July 2015 and June 2016 were reviewed. Patients were grouped by their VA format: (A) pre-emptive surgically created VA (SCVA), (B) tunneled central venous catheter (CVC) followed by SCVA creation, (C) long-term tunneled CVC only. Clinical events, number of investigations and procedures, hospital admissions, and incurred costs of the three groups were compared.

RESULTS

In the multivariable analysis, the cost incurred by the group A patients had no significant difference to that incurred in the group B patients (p = 0.08), while the cost of group C is significantly lower (p < 0.001). Both the 62.7% of group A with successful SCVA who avoided tunneled CVC usage, and those with a functionally matured SCVA in group B (66.1%), used fewer healthcare resources and incurred less cost for their access compared to those did not (p = 0.01, p = 0.02, respectively) during the first year of HD.

CONCLUSION

With comparable cost, a pre-emptive approach enables avoidance of tunneled CVC. Tunneled CVC only access format incurred lower cost and is suitable for carefully selected patients. Successful maturation of SCVA greatly affects patients' clinical journey and healthcare cost.

Accidental Diagnosis of Isolated Persistent Left Superior Vena Cava After an Elective Central Venous Access Procedure for Chronic Hemodialysis: Clinical Implications and Precautions From a Case Report

Persistent left superior vena cava (PLSVC) is the most frequent thoracic venous anatomical variant in the general population. Isolated PLSVC, without formation of the right superior vena cava, is described in 10% of cases of PLSVC only. While it can be associated with congenital heart disease, arrhythmias, and premature death, adult patients with PLSVC are mostly asymptomatic, and the diagnosis is usually accidental. We present the case of a 72-year-old male with end-stage renal disease who was started on urgent hemodialysis through a temporary non-tunneled femoral central venous catheter (CVC) in the SLED (slow low-efficiency dialysis) modality and later remained dependent on hemodialysis. At this stage, placement of a tunneled CVC in the right internal jugular vein was necessary and fluoroscopy guidance was not available. There were no complications during the procedure, but postoperative conventional chest radiography revealed an inadequate positioning of the CVC tip in the left hemithorax, crossing the midline. Subsequently, the diagnosis of PLSVC was obtained by performing a thoracic angio-CT scan, confirming CVC tip positioning inside the PLSVC, and also excluded the presence of cardiac defects or additional anatomical variations of the great vessels of the thorax. Early evaluation for the creation of autologous vascular access was started under our care, and there were no mechanical or other complications associated with hemodialysis sessions during early follow-up after discharge.

A pig model of tunneled dialysis catheter (TDC) infection and dysfunction: Opportunities for therapeutic innovation

BACKGROUND

Although tunneled dialysis catheters (TDC) are far from ideal, they still represent the main form of vascular access for most patients beginning dialysis. Catheters are easy to place and allow patients instant access to dialysis, but regardless of these benefits, catheters are associated with a high incidence of significant complications like bloodstream infections, central venous stenosis, thrombosis, and dysfunction. In the present study, we aim to describe and characterize a swine model of catheter dysfunction and bloodstream infection, that recreates the clinical scenario, to help to serve as a platform to develop therapeutic innovations for this important clinical problem.

METHODS

Six Yorkshire cross pigs were used in this study. Non-coated commercial catheters were implanted in the external jugular recreating the main features of common clinical practice. Catheters were aseptically accessed twice a week for a mock dialysis procedure (flushing in and out) to assess for and identify catheter dysfunction. Animals were monitored daily for infections; once detected, blood samples were collected for bacterial culture and antibiograms. Study animals were euthanized when nonresponsive to treatment. Tissue samples were collected in a standardized fashion for macroscopic inspection and histological analysis.

RESULTS

The data analysis revealed an early onset of infection with a median time to infection of 9 days, 40% of the isolates were polymicrobial, and the average time to euthanasia was 20.16 ± 7.3 days. Median time to catheter dysfunction onset was 6 days post-implantation. Postmortem dissection revealed external fibrin sheath and internal thrombosis as the main causes of catheter dysfunction. There was also evidence of central venous stenosis with positive cells for αSMA, CD68, Ki67, Smoothelin, and Vimentin within the venous neointima.

CONCLUSIONS

The described model represents a reliable and reproducible large animal model of catheter dysfunction and bloodstream infection, which recreates all the main complications of TDC's and so could be used as a validated large animal model to develop new therapies for TDC related infection, thrombosis/dysfunction and central venous stenosis.

Bleeding Complications in Uremic Patients After Ultrasound-Guided Central Venous Catheter Placement

Introduction

Bleeding associated with elevated blood urea nitrogen (BUN) is a known complication. Patients with uremia require a central venous catheter insertion by dialysis. The relation between BUN and bleeding complications during central venous catheter insertion is not yet clear.

Objective

We described the frequency of complications associated with central venous catheter implantation in uremic patients and evaluated the statistical relationship between bleeding complications and catheter type, number of punctures, and catheter insertion site. Also, we determined if any value of BUN is associated with bleeding complications.

Methods

We included patients with a serum value of BUN >70 mg/dl that required insertion of a central venous catheter. The quantitative variables were expressed through the measure of central tendency. A bivariate analysis and a ROC curve were performed.

Results

A total of 273 catheters were included in this study. Bleeding complications were detected in 69 cases (25.3%), and local bleeding was the most frequent complication in 51/69 cases. Statistically significant association was not established. We did not find a specific cut-off value directly related to BUN levels and the rate of complications.

Conclusion

Bleeding complications associated with the insertion of central venous catheter and the suspected disorder of hemostasis given by BUN levels >70 mg/dl are common. It was not possible to determine a BUN cut-off value to predict complications. The association analysis was not conclusive. High BUN levels should not be considered a high-risk condition for central venous cannulation under ultrasound guidance performed by trained personnel.

Difficult cannulation of hemodialysis arteriovenous fistula - Role of imaging in access management (DICAF STUDY)

BACKGROUND

Difficulty in cannulation of arteriovenous fistula (AVF) can lead to inadequate dialysis, transient to permanent loss of access and increases dependency on bridging catheters. This study aimed to analyze the causes for difficult fistula cannulation, using various imaging modalities.

METHODOLOGY

This was a retrospective single-center observational study conducted between October 2017 and June 2018. Patients whose fistulae were difficult to cannulate were initially evaluated by physical examination followed by doppler ultrasonography or/and fistulogram as necessary. The patients were divided into two groups that is, primary difficult cannulation (within first three months of creation of fistula) or secondary difficult cannulation (after three months).

RESULTS

We encountered difficult cannulation in 43 patients. About 60% were primary difficult cannulations. Most common causes for difficulty in cannulation were cannulation zone (CZ) stenosis (23.3%), immature fistula (20.9%), outflow stenosis (18.6%), inflow stenosis (11.6%), anatomical abnormalities (11.6%), outflow plus CZ stenosis (9.3%) and inflow plus CZ stenosis (4.7%). Among patients with primary difficult cannulation, immature fistula (34.6%) was the most common cause, whereas CZ stenosis (47.1%) was the most common etiology for secondary difficult cannulation. Edema leading to difficult cannulation was found in 12 patients (27.9%), all of which was due to central vein stenosis. Cannulation resulted in hematoma, fistula thrombosis, failure of fistula and pseudoaneurysm in 83.7%, 27.9%, 16.3%, and 2.3% of cases respectively. Bridging temporary dialysis catheter placement was required in 67.4% patients. Ultrasound doppler had lower diagnostic value when compared to fistulogram (71.4% vs 93.9%, p = 0.014).

CONCLUSION

Difficulty in cannulating the arteriovenous fistula is a common problem in hemodialysis patients. We suggest that patients whose fistulae are difficult to cannulate should undergo early radiological evaluation to decrease catheter dependency and access failure.

Revision of Aneurysmal Arteriovenous Access with Immediate Use Graft Is Safe and Avoids Prolonged Use of Tunneled Hemodialysis Catheters

INTRODUCTION

Aneurysmal AVF can pose a difficult treatment dilemma for the vascular surgeon. Prolonged tunneled dialysis catheters (TDC) in patients requiring long-term dialysis are associated with significantly increased mortality compared to arteriovenous fistulas (AVF). We aimed to elucidate the outcomes of aneurysmal AV access revision with aneurysm resection and Artegraft® (LeMaitre, New Brunswick, NJ) Collage Vascular Graft placement to avoid prolonged use of TDCs.

METHODS

We reviewed all patients with aneurysmal AV access in which the access was revised with aneurysm resection and jump graft placement at a single institution from 2018 to 2021. Outcomes were time to cannulation, reintervention rates, time to reintervention and patency (primary, primary assisted and secondary). Patency rates were estimated with Kaplan-Meier Survival analysis.

RESULTS

A total of 51 revised aneurysmal AV access in 51 patients were studied, of which 23.5% (n=12) had perioperative TDC placement. Three patients were done for emergent bleeding. The cohort was 62.8% male (n=32) with a median age of 58 years (IQR: 49-67). Most patients had brachiocephalic AVF (n=37 [72.6%]). Median follow up time was 280 days. Median time to cannulation was 2 days. Time to cannulation was significantly longer in patients with perioperative TDC as compared with those without TDC (24 days vs 2 days, P<0.001). Reintervention was required in 41.2% of patients (n=21), at median time of 47 days. At 30, 90, 180, and 365 days, primary patency rates were 84.3%, 78.3%, 66.6%, and 54.9%; primary assisted patency rates were 94.1%, 88.1%, 79.4%, and 79.4% and secondary patency rates were 100%, 97.8%, 91.6% and 91.6% respectively.

CONCLUSIONS

Revision of aneurysmal AV access (urgent or elective) with Artegraft as jump graft is safe, with acceptable short and mid-term patency results. This allows dialysis patients to continue to have a functional access, decreasing the need for a tunneled catheter and reducing the associated risk of sepsis and increased mortality. This should be considered for all patients with aneurysmal, dysfunctional fistulas to maintain AV access and avoid TDC placement.

Determinants of Tunneled Hemodialysis Catheter Implantation Time by Ultrasound Guidance: A Single-Center Cross-Sectional Study

BACKGROUND

We have previously reported that the ultrasound (US)-guided tip positioning is an accurate and safe procedure for placement of retrograde- and antegrade-tunneled hemodialysis catheters (HDCs). However, determinants of tunneled hemodialysis catheter implantation time by using US guidance have not been described yet. Therefore, we here report a comparative analysis to identify determinants of implantation time for retrograde- and antegrade-tunneled HDCs placement by US guidance.

METHODS

We performed a cross-sectional study to compare implantation time for US-guided tip positioning of retrograde- and antegrade-tunneled HDCs. We included a total number of 47 tunneled HDC insertions, including 23 retrograde tunneled and 24 antegrade-tunneled HDCs in patients requiring placement of an HDC for the temporary or permanent treatment of end-stage kidney disease (ESKD) in a single-center, cross-sectional pilot study.

RESULTS

We show that clinical and laboratory parameters did not differ between retrograde- and antegrade-tunneled HDC implantations. There was a tendency for shorter implantation time in antegrade-tunneled HDCs, although not statistically significant. Finally, we identified an independent inverse association between body weight (BW) and platelet counts with HDC implantation time specifically in antegrade-tunneled HDCs.

CONCLUSION

In this study, we identified determinants for tunneled HDC implantation time that might be relevant for patients and interventionists.

May position of hemodialysis catheter tip have a direct effect on its patency? Positive results of a preliminary study on its rotation

Renal transplant therapy is essential in patients with End-Stage Renal Disease (ESRD). It is used in patients awaiting a kidney transplant or those who cannot be a transplant candidate. Central venous catheter is one of the most used access routes worldwide but has been recorded as the one with highest mortality and morbidity rate. Thromboembolic events have played a major part for that. This is a descriptive-analytical study, which conducted in a university treatment center in Tehran, Iran. A total of 225 patients were selected for this study that 108 were excluded because of our criteria. Statistical analysis was performed by SPSS v19 and a total of 117 patients were included in this study. The average age of the patients was 51.62±11.26. 79 (67.5%) and 38 (32.5%) patients had medial and lateral tip direction, respectively. The catheter of 85(72.6%) and 32(27.4%) patients was patent and occluded, respectively. The average catheter tip occlusion time in both groups was 22.5 and 7.5 months. Three-month, six-month, twelve-month, and twenty-four-month patency rate were 99%, 94%, 88%, and 30%, respectively. our findings suggest that medial direction of the tip of the catheter reduces complications caused in CVS. Because our study has been conducted in a small scale and there is lack of similar studies, our team suggests extension to a larger scale to confirm or not our results.

Internal Jugular Central Venous Catheter Tip Migration: Patient and Procedural Factors

Background: The ideal central venous catheter (CVC) tip position placement is controversial, and CVCs do not remain in a fixed position after placement. This study evaluates both patient and procedural factors which may influence CVC tip migration and subsequent catheter dysfunction. Materials and Methods: This study evaluates CVC placements at a single institution. Patient age, gender, body mass index (BMI), catheter laterality, CVC type and indication for central venous access were recorded. Catheter tip location relative to the carina was measured at time of placement and removal utilizing supine fluoroscopic imaging. Patients’ electronic medical records were reviewed for evidence of catheter dysfunction. Statistical analysis was performed utilizing odds ratios and two tailed Student’s t-test. Results: 177 patients were included (101 female; mean age 55; mean BMI 29.2). Catheter types included 122 ports, 50 tunneled large bore central venous catheters (≥9 French), and 5 tunneled small bore central venous catheters (<9 French). 127 were right sided catheters, and 50 were left sided. Left sided CVCs had a mean cranial tip migration of 3.2 cm (standard deviation ±2.9 cm) compared to 0.8 cm (standard deviation ±1.9 cm) for right sided catheters (p = 0.000008). Catheters that migrated cranially by >2 cm had more than 7× greater risk of dysfunction compared to catheters that migrated ≤2 cm (odds ratio of 7.2; p = 0.0001). Left sided CVCs were significantly more likely to have >2 cm of cranial migration (odds ratio 6.9, 95% CI 3.4−14.2, p < 0.0001) and had a higher rate of dysfunction, likely due to this cranial migration (32% vs. 4.7%; p = 0.00001). Gender and BMI were not found to be associated with catheter dysfunction or an increased odds ratio of >2 cm cranial migration. Conclusions: Left-sided CVCs migrate an average of 2.4 cm cranially more than right-sided catheters. Additionally, when migration occurs, left-sided catheters are more likely to be dysfunctional. These suggest that lower initial placement may be beneficial in left-sided catheters.

Pre-Procedure Thrombocytopenia and Leukopenia Association with Risk for Infection in Image-Guided Tunneled Central Venous Catheter Placement

Placement of image-guided tunneled and non-tunneled large-bore central venous catheters (CVCs) are common procedures in interventional radiology. Although leukopenia and/or thrombocytopenia are common at the time of placement, the roles these factors may have in subsequent catheter-related infection have yet to be investigated. A single-institution retrospective review was performed in patients who underwent CVC placement in interventional radiology between 11/2018–6/2019. The electronic medical record was used to obtain demographics, procedure details, pre-placement laboratory values, and the subsequent 90-day follow-up. A total of 178 tunneled and non-tunneled CVCs met inclusion criteria during this time period. White blood cell (WBC) and platelet counts were found to be significant risk factors for subsequent infection. Administration of pre-procedure antibiotics was not found to be a significant factor for subsequent infection (p = 0.075). Leukopenia and thrombocytopenia at the time of CVC placement are both risk factors of line infection for tunneled large-bore CVCs. This should lead to the consideration of using a non-tunneled CVC when clinically feasible, or the delayed placement of these catheters until counts recover.

The Rapid Atrial Swirl Sign for Ultrasound-Guided Tip Positioning of Retrograde-Tunneled Hemodialysis Catheters: A Cross-Sectional Study from a Single Center

Background: Chronic kidney disease (CKD) is a common medical problem in patients worldwide, with an increasing prevalence of patients with end-stage kidney disease (ESKD) requiring renal replacement therapy (RRT). In patients requiring RRT for more than two weeks or those who develop ESKD, tunneled hemodialysis catheter (HDC) insertion is preferred, based on a lower risk for infectious complications. While the efficacy of ultrasound (US)-guided tip positioning in antegrade-tunneled HDCs has previously been shown, its application for the insertion of retrograde-tunneled HDCs has not been described yet. This is especially important, since the retrograde-tunneled technique has several advantages over the antegrade-tunneled HDC insertion technique. Therefore, we here report our first experience of applying the rapid atrial swirl sign (RASS) for US-guided tip positioning of retrograde-tunneled HDCs. Methods: We performed a cross-sectional study to assess the feasibility of applying the RASS for US-guided tip positioning of retrograde-tunneled HDCs. We performed a total number of 24 retrograde-tunneled HDC insertions in 23 patients (requiring placement of a HDC for the temporary or permanent treatment of ESKD) admitted to our Department of Nephrology and Rheumatology at the University Medical Center Göttingen, Germany. Results: The overall success rate of applying the RASS for US-guided tip positioning of retrograde-tunneled HDCs was 24/24 (100%), with proper tip position in the right atrium in 18/23 (78.3%), or cavoatrial junction in 5/23 (21.7%) when RASS was positive and improper position when RASS was negative in 1/1 (100%), confirmed by portable anterior-posterior chest radiography, with only minor post-procedural bleeding in 2/24 (8.3%). In addition, this insertion technique allows optimal HDC flow, without any observed malfunction. Conclusion: This is the first study to investigate the efficacy of the RASS for US-guided tip positioning of retrograde-tunneled HDCs in patients with ESKD. Application of the RASS for US-guided tip positioning is an accurate and safe procedure for the proper placement of retrograde-tunneled HDCs.

The efficacy of single suture for exit site wound closure and stabilization of hemodialysis central tunneled catheter

Introduction:

The majority of the end-stage renal disease patients begin hemodialysis with the central tunneled catheter as a permanent or bridge vascular access. The procedure of central tunneled catheter insertion can be complicated by exit site bleeding, prolonged tunnel healing, and infection. The study aimed at evaluating whether the catheter exit site wound closing with a single-suture method is equally effective as the double suture method, which is most frequently applied. The assumption was that the single-suture method, which is less traumatizing for the skin, could offer an advantage for the patients with “paper” skin, that is, elderly, after long-term immunosuppressive treatment.

Methods:

Insertion of central tunneled catheter with antegrade tunnel formation was performed in 140 patients divided randomly into two groups of 70 patients using either single-suture method or double suture method.

Results:

Follow-up observations revealed a comparable number of early complications, that is, bleeding or exit site infection, in about 26% of the patients from both groups. No difference appeared in the catheter displacement, either. The percentage of patients with a prolonged central tunneled catheter exit site wound healing was not significantly lower in the single-suture method group: 5.8% versus 11.3%, p = 0.367. There was no impact of single-suture method versus double suture method on the central tunneled catheter long-term function and survival.

Conclusion:

The single-suture method of the central tunneled catheter exit closure is equal in efficacy to the double suture method. Its potential benefit for the patients with an increased risk of poor wound healing should be tested in further study.

Factors influencing the long-term outcome of tunneled hemodialysis catheters

PURPOSE

To review the incidence and type of tunneled hemodialysis catheter (THC) complications in a large cohort of patients with end-stage renal disease. Additionally, the longevity of the THC and factors predicting high risk for catheter complications were assessed.

MATERIAL AND METHODS

Between August 2009 and December 2016, a cohort of 538 patients underwent primary THC insertion; in 119 patients, THC was inserted after failed arteriovenous fistula or graft. Patients without available clinical follow-up data (n = 67) were excluded for further analysis. The Charlson comorbidity index (CCI) was calculated for each patient. The cumulative incidence function (CIF) was used for THC overall longevity, while Cox proportional hazards models were used for risk factor analysis.

RESULTS

In 352 patients, THC was inserted in a virgin neck. THC-related complications were observed in n = 104 (29.55%) of the patients. Infection occurred in n = 38 (10.80%) and malfunction, related to thrombosis or mechanical damage, in n = 45 (12.78%). Removal of the THC for the purpose of switching to alternative dialysis methods was planned in n = 135 (38.4%). The remaining patients were still alive with a functioning THC (n = 18; 5.11%) or died (n = 95; 27%) with a functioning THC. The THC survival rate was 82.67%, 78.13%, 74.15%, 72.96%, 71.02%, and 70.63% on follow-up after 6 months, and after 1-5 years, respectively. Gender, CCI, age, and site of placement of the catheter were found not to affect the life of the catheter.

CONCLUSION

The overall complication rate in primary inserted THC was nearly 30% and mainly related to infection and malfunction. THC survival was more than 70% after 5 years, which supports its use for permanent dialysis access, irrespective of gender, CCI, age, and jugular side of THC placement.

Management of Inadvertent Supra-aortic Arterial Lesions During Central Venous Access Procedures: Report of Six Cases and Proposed Algorithm

Accidental supra-aortic arterial cannulation during central venous catheter (CVC) insertion is a rare and serious complication associated with risk of vascular and neurologic complications. The aim of this study is describing our 6 cases experience and propose a management algorithm. We retrospectively evaluated the diagnosis and treatment of six patients arrived at our Department for accidental supra-aortic arterial cannulation during CVC insertion. They underwent Doppler Ultrasonography (DUS) or Computed Tomography Angiography (CTA) to confirm the arterial damage and to decide the correct therapeutic pathway. Four patients underwent DUS as the shallow location of injured arteries and 2 patients CTA because of the arterial damage deeply located. Surgical procedure with direct arterial suture was performed in four patients. Endovascular treatment with stent graft deployment was carried out in two patients. All procedures were conducted successfully: technical success (immediate hemostasis and vessel patency) was obtained in 100% of the cases. Postoperative imaging (DUS or CTA) confirmed the absence of arterial bleeding and the arterial patency. No perioperative mortality or complications occurred. After a careful review of literature and our case series, we proposed an algorithm to delineate the optimal treatment strategy, explaining that early and careful diagnosis (by DUS or CTA) and prompt repair appear crucial to achieve good outcomes and clarifying that an endovascular technique (stent graft placement or vascular closure device) seems to be the best treatment in these cases. Finally, an open surgical technique could be indicated in case of common carotid artery injury and concurrent catheter passing through the target vein.

Therapeutic plasma exchange: single-center experience in children with kidney disorders

BACKGROUND

Therapeutic plasma exchange (TPE) is used in kidney diseases as an adjunct treatment. Little has been described as to its effectiveness in kidney disorders in children. This study aimed to assess the safety, efficacy, and outcomes of patients who underwent TPE for kidney indications.

METHODS

Retrospective chart review of patients receiving TPE from 2010 to 2018 for kidney indications, such as antibody-mediated rejection, bone marrow transplant-associated thrombotic microangiopathy (TA-TMA), atypical hemolytic uremic syndrome, transplant recurrence of focal segmental glomerulosclerosis, and glomerulonephritis. Outcomes assessed were trends in kidney function, mortality, and progression to stage 5 chronic kidney disease (CKD 5). Significant hypocalcemia was defined as ionized calcium < 1 mmol/L.

RESULTS

A total of 641 TPE procedures were performed on 47 patients (25 male). Average age was 12.8 ± 5.9 years. Median glomerular filtration rate (GFR) improved from baseline to end of TPE treatments (pre 44.9 (19.8, 79), end 56.1 (23, 98) [p = 0.02]). Ten out of 47 children developed CKD 5. Seven out of 47 patients died; 5 had TA-TMA. Initial 7 consecutive sessions were reviewed for complications. Among 335 procedures, 41 episodes of significant hypocalcemia were noted (12.2%); only 1 was symptomatic. Of the 26 episodes (7.7%) of allergic reactions, all were associated with the use of FFP; 5 were anaphylactic. No TPE-associated mortality was noted.

CONCLUSIONS

TPE is a relatively well-tolerated useful adjunct therapy in children with kidney indications. The benefit of TPE has to be balanced with risks such as hypocalcemia and allergic reactions which can occur more frequently with FFP. Graphical abstract.

Hybrid angioplasty-catheter placement procedure performed in a hemodialysis patient with central venous obstruction disease. Presentation of a case

Obstruction or occlusion of the central veins (Central venous disease, CVD) represents a major complication in hemodialysis patients (HD) limiting central venous access available for a central venous catheter placement. Endovascular treatment with percutaneous transluminal angioplasty (PTA) is the first therapeutic option to restore patency and gain access. This case presents our initial experience of a HD patient with CVD treated with a combination therapy of a balloon PTA to the left brachiocephalic trunk, through the right hepatic vein and standard catheter placement technique to the previously occluded junction of the left internal jugular vein to the left subclavian vein.

How To Prescribe And Troubleshoot Continuous Renal Replacement Therapy: A Case-Based Review

Continuous RRT (CRRT) is the preferred dialysis modality for solute management, acid-base stability, and volume control in patients who are critically ill with AKI in the intensive care unit (ICU). CRRT offers multiple advantages over conventional hemodialysis in the critically ill population, such as greater hemodynamic stability, better fluid management, greater solute control, lower bleeding risk, and a more continuous (physiologic) approach of kidney support. Despite its frequent use, several aspects of CRRT delivery are still not fully standardized, or do not have solid evidence-based foundations. In this study, we provide a case-based review and recommendations of common scenarios and interventions encountered during the provision of CRRT to patients who are critically ill. Specific focus is on initial prescription, CRRT dosing, and adjustments related to severe hyponatremia management, concomitant extracorporeal membrane oxygenation support, dialysis catheter placement, use of regional citrate anticoagulation, and antibiotic dosing. This case-driven simulation is made as the clinical status of the patient evolves, and is on the basis of step-wise decisions made during the care of this patient, according to the specific patient's needs and the logistics available at the corresponding institution.

Presence of retained calcified fibrin sheath after central venous catheter removal: A systematic literature review

Central venous catheters (CVC) are used in many clinical settings for a variety of indications. We performed a systematic literature review concerning case reports of retained calcified fibrin sheaths after dialysis CVC removal. The aim of our study was to systematize the knowledge regarding clinical management of this phenomenon, placing special emphasis on diagnostic radiological features in different imaging modalities, including chest radiography, echocardiography, computed tomography, and magnetic resonance imaging. We discuss the most common risk factors associated with this CVC complication. In our review, we found eight cases of hemodialysis patients. The most common risk factors associated with calcified fibrin sheath formation in the analyzed cases were pro-thrombotic and pro-calcification factors related to patient comorbidities, and prolonged catheter dwell time. Differentiating between a calcified fibrin sheath (present in about 6% of patients with long-term indwelling CVC as diagnosed by computed tomography) and a retained catheter tip can be challenging. The initial diagnosis based on imaging methods was incorrect in most of the analyzed cases. This suggests that some cases of retained fibrin sheaths may remain undetected or misinterpreted. This is important in patients with known pro-thrombotic and pro-calcification risk factors and prolonged catheter dwell time. Therefore, implementation of preventive strategies, familiarity with radiological findings of this phenomenon, comparison with previous imaging studies, and an overall comprehensive assessment with clinical data is imperative.

Unintentional puncture of thyroid cyst during insertion of dialysis catheter

Central venous catheter (CVC) for hemodialysis are frequently implanted to the internal jugular vein. Thyroid cysts are commonly shown in ultrasound examination and their recognition should not pose a problem. Herby we present an uncommon case of the thyroid cyst unintended puncture, during an attempt of CVC insertion. No further clinical consequences were observed. For all practitioners, involved in interventional nephrology, such complication may be of the utmost importance.

Long-term outcome of posterior approach insertion of tunneled cuffed catheter: A single clinic retrospective analysis

BACKGROUND AND OBJECTIVES

For patients who rely on a tunneled cuffed catheter, the internal jugular vein is the preferred site of insertion. A few studies have suggested that the posterior approach for central lines is equivalent or better in comparison to the conventional central approach. However, there have been fewer studies examining tunneled cuffed catheter insertion using the posterior approach. We have performed many posterior insertions of tunneled cuffed catheters in our practice, and because the technique has not yet been comprehensively studied for long-term use, we performed a retrospective study to evaluate the safety and efficacy of posterior approach for tunneled cuffed catheter in maintained hemodialysis patients.

METHODS

A retrospective review was conducted of 200 hemodialysis patients who were treated with tunneled cuffed catheters over a period of 3 years. There were 104 patients in the study group, as well as a 96-patient control group, who underwent catheter insertion by central approach. The clinical follow-up data were collected and analyzed.

RESULTS

All catheters were successfully placed. The mean primary patency days per catheter were 712 catheter days for the study group and 585 catheter days for the control group. The episode of catheter infection was similar in both groups (p = 0.874), but the case of total catheter dysfunction was significantly lower in the study group compared to the control group (p = 0.006). The cumulative patency of catheters was higher in the study group than that in the control group (p = 0.02), while patient survival was the same in the two groups (p = 0.325).

CONCLUSION

The posterior approach is safe, and similar infection rates were observed with lower dysfunction rates compared to tunneled catheter insertion by the conventional central approach.

Vascular Access Failure - Cause or Complication of Central Venous Catheterization: Case Report

The quality of life and patient survival rate in terminal chronic renal insufficiency depends on the duration of vascular approaches. Dialysis catheters are used to establish an adequate vascular approach when emergency hemodialysis is indicated and when all approaches are exhausted. Complications of CVC can be classified into three categories: mechanical (hematoma, arterial puncture, pneumothorax, hemothorax, catheter misplacement, and stenosis), infectious (insertion site infection, CVC colonization, and bloodstream infection) and thrombotic (deep vein thrombosis). Despite the increasing prevalence of haemodialysis patients with complex access issues, there remains no consensus on the definition of vascular access failure or end-stage vascular access. The dilema in these cases remains whether the generalized vascular insufficiency is the cause or a complication of exhausted vascular accesses. This case report is one of the examples of combined complications with generalized vascular access insufficiency. During the year and a half of the chronic dialysis program, the patient had several changes of vascular approaches, and each approach became dysfunctional in certain time due to various causes. After six months of successful hemodialysis, the patient was admitted with signs of infection and during hospitalization was again subjected to multiple changes of the vascular approach due to infection, thrombosis, and vascular access failure.

Challenges of Vascular Access in the Pediatric Population

The incidence and prevalence of renal replacement therapy has continued to increase in the pediatric population. Recent data have shown that hemodialysis was the most frequently used dialysis modality, especially in pediatric ESRD patients (age 0-21 years). A well-functioning vascular access is required for effective hemodialysis and choosing the best vascular access option for pediatric patients can be difficult. Pediatric vascular options include arteriovenous fistula, arteriovenous graft, and central venous catheters (CVCs). There is a national initiative for fistula first-catheter last approach; however, CVCs have been reported as the most conventionally utilized vascular access option in pediatric patients. The use of CVCs should be minimized or avoided as they are associated with high risk of infections, thrombosis, and other complications. Thus, it is important for practitioners to plan appropriately in advance, practice good clinical judgment, and assure that the best vascular access is placed according to the patient's needs. Therefore, this article reviews the different types of pediatric vascular access and the associated benefits and potential complications of each.

Consensus on technical procedures for simulation-based training in anaesthesiology: A Delphi-based general needs assessment

BACKGROUND

Anaesthesiologists are expected to master an increasing number of technical procedures. Simulation-based procedural training can supplement and, in some areas, replace the classical apprenticeship approach during patient care. However, simulation-based training is very resource-intensive and must be prioritised and optimised. Developing a curriculum for simulation-based procedural training should follow a systematic approach, eg the Six-Step Approach developed by Kern. The aim of this study was to conduct a national general needs assessment to identify and prioritise technical procedures for simulation-based training in anaesthesiology.

METHODS

A three-round Delphi process was completed with anaesthesiology key opinion leaders. In the first round, the participants suggested technical procedures relevant to simulation-based training. In the second round, a needs assessment formula was used to explore the procedures and produce a preliminary prioritised list. In the third round, participants evaluated the preliminary list by eliminating and re-prioritising the procedures.

RESULTS

All teaching departments in Denmark were represented with high response rates in all three rounds: 79%, 77%, and 75%, respectively. The Delphi process produced a prioritised list of 30 procedure groups suitable for simulation-based training from the initial 138 suggestions. Top-5 on the final list was cardiopulmonary resuscitation, direct- and video laryngoscopy, defibrillation, emergency cricothyrotomy, and fibreoptic intubation. The needs assessment formula predicted the final prioritisation to a great extent.

CONCLUSION

The Delphi process produced a prioritised list of 30 procedure groups that could serve as a guide in future curriculum development for the simulation-based training of technical procedures in anaesthesiology.

Numerical Simulation of Hemodynamic Changes in Central Veins after Tunneled Cuffed Central Venous Catheter Placement in Patients under Hemodialysis

The tunneled central venous catheter (CVC) plays an important role for hemodialysis patients, but CVC-related thrombosis in the central veins remain problematic. This study is the first try to numerically find out what hemodynamic parameters are predisposed to the initiation and formation of thrombus after CVC insertion. And the potential relationship between hemodynamic parameters and the incidence rates of thrombosis occurrence was explored. The results revealed that the CVC insertion led to a significant increase of hydraulic resistance, wide-ranging abnormally high wall shear stress (WSS), and a great loss of flow rotation in the vein. Moreover, the clinical data showed that thrombosis mainly occurred at sections where most blood flow lost spiral rotation after the CVC insertion, but no corresponding match was observed between the occurrence of thrombosis and the flow velocity or WSS. We speculate that the destruction of the flow rotation in the central vein is a precursor to the thrombus formation around CVC, and an introduction of spiral flow with the CVC insertion may possibly help to protect the central vein from thrombosis. Further animal and clinical experiments should be carried out to test and verify this speculation.