Impact of Previous Tunneled Vascular Catheters and their Location on Upper Limb Arteriovenous Fistula Function.

Background: Long-term arteriovenous fistula (AVF) survival has been shown to be adversely affected by the presence of previous tunneled vascular catheters (TVC). We analyzed the effect of previous TVCs and their location (ipsilateral versus contralateral) on the successful function of upper-limb AVFs in the first 12 months after creation. Methods: We retrospectively reviewed clinical data on patients' first upper-limb AVFs, created between January 2013 and December 2017. We analyzed the rates of successful AVF function (successful cannulation using two needles for ≥50% sessions over a 2-week period) at 6 and 12 months after creation, time to AVF maturation, and rates of assisted maturation. Results: In total, 287 patients with first AVFs were identified, of which 142 patients had a previous TVC (102 contralateral, 40 ipsilateral) and 145 had no previous TVC. The no TVC group had higher rates of AVF function at both 6 months (69% versus 54%, OR, 1.84; 95% CI, 1.00 to 3.39, P=0.05) and 12 months (84% versus 64%, OR, 3.10; 95% CI, 1.53 to 6.26, P=0.002) compared with the TVC group. The contralateral TVC group had higher rates of AVF function at 6 months (60% versus 40%, OR, 2.21; 95% CI, 1.01 to 4.88, P=0.05), but not at 12 months (66% versus 58%, OR, 1.42; 95% CI, 0.62 to 3.25, P=0.40) compared with the ipsilateral TVC group. The median time to AVF maturation in the contralateral and ipsilateral TVC groups were 121.5 and 146 days respectively (P=0.07). Assisted maturation rates were lower in no TVC group compared with the TVC group (12% versus 28%, P=0.007), but similar between the contralateral and ipsilateral TVC groups (29% versus 26%, P=0.74). Conclusions: Previous TVC use was associated with poorer AVF function at 6 and 12 months, with a higher rate of assisted maturation. The presence of an ipsilateral TVC was associated with lower successful AVF use at 6 months, compared with contralateral TVC.

The Utility of Sonographic Assessment in Selecting Patients for Percutaneous Insertion of Peritoneal Dialysis Catheter.

BACKGROUND: Percutaneous insertion of peritoneal dialysis (PD) catheters by nephrologists is a safe and effective alternative to open surgical techniques. These patients are usually carefully selected due to anatomical considerations and medical comorbidities, with the current literature suggesting exclusion of patients with prior abdominal surgery. METHOD: We conducted a retrospective cohort study of pre-dialysis patients who attended a preprocedural clinic in a tertiary center over 6 years. Procedural complications and catheter survival were assessed. Chi-squared test and Kaplan-Meier survival analysis were undertaken. Inpatient assessments were excluded. RESULTS: A total of 217 patients were assessed, of whom 171 (78.8%) were accepted for percutaneous PD catheter insertion by a nephrologist. The key exclusion criteria were: (1) the clinical presence of abdominal hernia (p < 0.001), (2) ultrasound findings of skin to peritoneum depth of > 5.5 cm (p < 0.001) and (3) ultrasound findings of impaired visceral slide test (p < 0.001). Prior abdominal surgery was not a default exclusion criterion (p = 0.1), as 63 patients (37%) with prior abdominal surgery, average of 1.3 prior surgeries per patient, were assessed as appropriate for the percutaneous procedure. There was no difference in the procedural complication rate and catheter survival between patients with and without prior abdominal surgery. CONCLUSION: A comprehensive preprocedural assessment utilizing ultrasound permits an objective selection of patients for percutaneous insertion of PD catheters by nephrologists. This allowed for successful and safe percutaneous insertion of PD catheters in patients who may have otherwise been excluded, e.g., prior abdominal surgery, patients with large bilateral polycystic kidneys, and central obesity.

The impact of tunnelled vascular catheters on time to arteriovenous fistula creation.

PURPOSE: The purpose of this study is to examine the effect of the presence of tunnelled vascular catheter (TVC) on physician referral and surgeon review and operating patterns and ultimately time of creation of permanent haemodialysis (HD) access. METHODS: A retrospective analysis of TVC and arteriovenous fistulae (AVF) databases in 2010. Physician referral time and surgical time to operation were compared between patients commencing HD with TVC and a control group who commenced HD with AVF. RESULTS: The AVF group (n = 27) commenced HD with an AVF and TVC group (n = 49) commenced HD via a TVC. Time from physician referral to surgeon review in the AVF vs. TVC group was 29 vs. 35 days (p = 0.6). Time from surgeon review to access creation was 43 vs. 50 days (p = 0.4). However, in the TVC group, the time from TVC insertion to physician referral to a surgeon was an additional 109 ± 20 days. Subgroup analysis of 11 TVC patients (23%) presenting at end stage without AVF (crash starters) had a TVC to physician referral time of 103 ± 75 days, physician referral to surgeon review of 14.4 ± 4 days and surgeon review to AVF of 67 ± 23 days. CONCLUSIONS: The presence of a TVC is associated with a significant delay (>3 months) before physicians make a referral for surgeon review. There was no surgeon-related delay to access creation related to the presence of a TVC.