Challenges of long-term vascular access in pediatric hemodialysis: Recommendations for practitioners

Establishing an autogenous vascular access program in a Guatemalan comprehensive pediatric nephrology center

BACKGROUND

The Guatemalan Foundation for Children with Kidney Diseases collaborated with Bridge of Life, a not-for-profit charitable organization, to establish a vascular access program. We reviewed our experience with graded surgical responsibility and structured didactic training, creating arteriovenous fistulas (AVF) for Guatemalan children.

METHODS

Pediatric vascular access missions were completed from 2015 to 2023 and analyzed retrospectively. Follow-up was completed by the Guatemalan pediatric surgeons, nephrologists, and nursing staff. AVF patency and patient survival were evaluated by Kaplan-Meier life-table analysis with univariate and multivariable association between patient demographic variables by Cox proportional hazards models.

RESULTS

Among a total of 153 vascular access operations, there were 139 new patient procedures, forming the study group for this review. The mean age was 13.6 years, 42.6% were female, and the mean BMI was 17.3. Radial or ulnar artery-based direct AVFs were established in 100 patients (71.9%) and ten of the 25 transposition procedures. Brachial artery inflow was required in 29 direct AVFs (20.9%). Two patients underwent femoral vein transpositions. Access-related distal ischemia was not encountered. Seven of the AVF patients later required access banding for arm edema; all had previous dialysis catheters (mean = 9, range 4-12). Primary and cumulative patency rates were 84% and 86% at 12 months and 64% and 81% at 24 months, respectively. The median follow-up was 12 months. Overall patient survival was 84% and 67% at 12 and 24 months, respectively. There were no deaths related to AVF access.

CONCLUSIONS

Safe and functional AVFs were established in a teaching environment within a Guatemalan comprehensive pediatric nephrology center.

Dialysis Access-Associated Steal Syndrome in High-Risk Patients Undergoing Surgery for Hemodialysis Access: A Systematic Review and Meta-Analysis of Preventive Operative Techniques

This systematic review and meta-analysis examine preventive operative techniques in high-risk patients undergoing surgery for hemodialysis access to mitigate the risk of Dialysis Access-Associated Steal Syndrome (DASS). Chronic kidney disease often leads to end-stage renal disease (ESRD), necessitating dialysis. Successful vascular access is crucial for efficient dialysis, but complications, such as DASS, pose significant challenges. DASS redirects arterial blood flow, affecting populations undergoing arteriovenous access surgery. This study aims to assess preventive strategies, including distal revascularization with interval ligation (DRIL) and extension techniques. A systematic search of PubMed, Cochrane Library, EMBASE, and Web of Science until 2022 identified 11 relevant studies. The inclusion criteria comprised non-pediatric hemodialysis patients reporting outcomes related to patency and complications. The data were analyzed using Review Manager 5.3.5 (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen). Meta-analysis indicated a significant association between DASS and arteriovenous fistula (AVF) or arteriovenous graft (AVG) procedures. Radiocephalic AVF (RC-AVF) and distal endovascular AVF procedures were favored. Various interventions addressed venous narrowing, including simple plication and loop interposition. The Modified by Inserted Latex Link for Endovascular Repair (MILLER) technique, DRIL, Extension Technique, and Proximalization of Arterial Inflow (PAI) were assessed for arterial bypass graft and blood supply preservation. This study underscores the importance of individualized strategies in preventing DASS during hemodialysis access surgery. Prophylactic measures, such as the extension technique, show promise, while DRIL remains effective in treatment. Ongoing research is imperative for optimizing outcomes in this complex patient population.

Population Pharmacokinetics of Vancomycin in Patients Receiving Hemodialysis in a Malian and a French Center and Simulation of the Optimal Loading Dose

PURPOSE

Vancomycin dosing remains challenging in patients receiving intermittent hemodialysis, especially in developing countries, where access to therapeutic drug monitoring and model-based dose adjustment services is limited. The objectives of this study were to describe vancomycin population PK in patients receiving hemodialysis in a Malian and French center and examine the optimal loading dose of vancomycin in this setting.

METHODS

Population pharmacokinetic analysis was conducted using Pmetrics in 31 Malian and 27 French hemodialysis patients, having a total of 309 vancomycin plasma concentrations. Structural and covariate analyses were based on goodness-of-fit criteria. The final model was used to perform simulations of the vancomycin loading dose, targeting a daily area under the concentration-time curve (AUC) of 400-600 mg.h/L or trough concentration of 15-20 mg/L at 48 hours.

RESULTS

After 48 hours of therapy, 68% of Malian and 63% of French patients exhibited a daily AUC of <400. The final model was a 2-compartment model, with hemodialysis influencing vancomycin elimination and age influencing the vancomycin volume distribution. Younger Malian patients exhibited a lower distribution volume than French patients. Dosing simulation suggested that loading doses of 1500, 2000, and 2500 mg would be required to minimize underexposure in patients aged 30, 50, and 70 years, respectively.

CONCLUSIONS

In this study, a low AUC was frequently observed in hemodialysis patients in Mali and France after a standard vancomycin loading dose. A larger dose is necessary to achieve the currently recommended AUC target. However, the proposed dosing algorithm requires further clinical evaluation.

Survival of Tunneled Double Lumen-Cuffed Catheters in Children on Maintenance Hemodialysis - A Retrospective Cohort Study

Introduction

Survival of tunneled cuffed catheters (TCC), used widely in children, is complicated by infections and catheter dysfunction. In resource limited settings, where risk of complications could be higher and waiting period for transplantation longer, catheter survival determines patient survival. This study was conducted to determine infection free catheter survival rates, incidence of catheter failure and associated risk factors.

Methods

Children <18 years of age receiving maintenance hemodialysis through TCC at nephrology division of a pediatric hospital, over a period of 6 years. Data was collected with consecutive selection by a complete enumeration technique from pre-collected data sheets in the records. Exposure detected were catheter infections, thrombosis, and mechanical complications.

Results

Forty-five TCCs in 36 children studied for 12,590 catheter days showed catheter failure in 36%, due to catheter related infections in 75% and mechanical complications in 25%. The incidence of complications per 1000 catheter days was 1.19 infection, 1.03 thrombus, and 0.39 mechanical. Catheter-related blood stream infection (CRBSI) (15/36) was associated with thrombus in nine and led to mortality in three. The mean infection free catheter survival was 449 ± 42 days for cohort with 388 ± 38 days in Group A (premature catheter removal) and 593 ± 43 days in Group B (elective removal) (P = 0.03). Catheterization duration of 267 days predicted CRBSI (sensitivity 93%, specificity 66.7%) with area under the curve of 0.808.

Conclusions

Median infection free catheter survival was 449 days with catheter failure in 36%. CRBSI was the main cause of failure. Duration of catheterization greater than 267 days was a predictor of CRBSI.

Pediatric hemodialysis access

Pediatric hemodialysis access is a demanding field. Procedures are infrequent, technically challenging, and associated with high complication and failure rates. Each procedure affects subsequent access and transplants sites. The choice is made easier and outcomes improved when access decisions are made by a multidisciplinary, pediatric, hemodialysis access team. This manuscript reviews the current literature and offers technical suggestions to improve outcomes.

Iatrogenic vascular trauma and complications of vascular access in children

Vascular access is frequently a critical component of the diagnostic and therapeutic procedures required to manage childhood illnesses, including many emergent conditions and critical illnesses. Vascular access in the pediatric population presents unique challenges, and many clinical and technical factors must be considered to avoid complications that can occur with vascular access procedures. This article reviews various aspects of vascular access and associated iatrogenic trauma in children, including risk factors, management of complications, and preventive measures to avoid complications. It is only with a comprehensive understanding of the topic that vascular access in children can be performed safely, effectively, and efficiently.

Analysis of Different Vascular Accesses on Dialysis Quality and Infection Risk Factors of Hemodialysis Patients

Objective

To explore the influence of different vascular accesses on dialysis quality and infection risk factors of hemodialysis patients.

Methods

A total of 162 patients with end-stage renal disease admitted to our hospital from February 2018 to July 2020 were divided into two groups: cuff tunnel conduit (CTC) group and native arteriovenous fistula (AVF) group. Peripheral blood was collected before and 6 months after dialysis. The incidence of vascular recirculation was measured, and the risk factors of infection were analyzed.

Results

The levels of HB, Alb, CRP, BUN, Scr, and TP after dialysis in the two groups were lower than those before dialysis (P < 0.05). The Kt/V of patients in both groups did not exceed 1.2, and the URR value exceeded 60%. The results of independent-samples T test analysis documented that the Kt/V level of patients in the AVF group was higher than that of those in the CTC group after dialysis (P < 0.05). The results of the urea method revealed that 22 of 68 patients (32.35%) in the CVC group and 21 of 94 (22.34%) in the AVF group had vascular pathway recirculation. The χ² test showed that there was no remarkable difference in the incidence of vascular pathway recirculation between both groups (P > 0.05). However, the results of the nonurea method revealed that the incidence of vascular pathway recirculation in the AVF group was lower than that in the CVC group (P < 0.05). Multivariate logistic regression was used to further analyze the factors with statistical significance in the single factor results. It showed that age >60 years, dialysis duration >1 year, dialysis times, diabetes, hypertension, and CTC were all independent risk factors causing vascular access infection.

Conclusion

If all conditions permit, AVF hemodialysis is a better choice for patients with end-stage renal disease. For the elderly, long-term hemodialysis, and those with diabetes and hypertension, it is necessary to make detailed plans, strengthen the operation proficiency of CTC, and reduce the incidence of infection.