SHORT TERM OUTCOME OF AV FISTULA CREATED UNDER SUPRACLAVICULAR BRACHIAL PLEXUS BLOCK IN DIALYSIS PATIENTS

Vascular access is the lifeline of patients on maintenance hemodialysis. Among the options for access (arteriovenous fistulas, synthetic grafts, tunneled catheters), autogenous AV fistulas are considered the gold standard due to their superior longevity and lower risk of infection and complications. Clinical practice guidelines consistently recommend “fistula-first” for eligible patients. However, despite being the preferred access, AV fistulae are notorious for high rates of early failure. Primary failure (failure of the fistula to ever mature sufficiently for dialysis use) has been reported in roughly 20–60% of newly created fistulas, reflecting the challenges in achieving a usable fistula in every patient.

This study was a retrospective observational analysis of all hemodialysis patients who underwent creation of a new arteriovenous fistula at our hospital between April 2024 and July 2025. Patients were included if they had end-stage renal disease (ESRD) on maintenance hemodialysis and were referred for creation of a permanent vascular access (AV fistula). If patients underwent more than one fistula surgery in the study period, only the first attempt was considered for this analysis.

Outcomes and Definitions: The primary outcome of interest was AVF patency at 6 months post-creation. We defined a fistula as patent at 3 months if it could be used for dialysis at 3rd month post-surgery. Primary failure was defined as a fistula that never matured. Secondary failure refers to fistulae that had initial function but later failed. The cohort was studied for a total of 6 months and all-cause mortality  at 6 months was also noted. Fistula outcomes were ascertained from dialysis unit records and vascular surgery follow-up notes.

Statistical Analysis: Continuous variables were reported as mean ± standard deviation or median with range, as appropriate. Categorical variables (e.g. patency rates, comorbidity prevalence) were reported as counts and percentages. Given the sample size, no formal hypothesis testing or multivariate analysis was performed. We did a subgroup descriptive comparison of outcomes by fistula type (forearm vs upper arm). 

A total of 49 patients (35 males and 14 females) underwent AV fistula creation during the study period. The mean age was 54.6 ± 15.2 years (median 55, range 20–81 years). Hypertension was the most common comorbidity, present in 38 patients (77.6%). Diabetes mellitus was present in 24 patients (49.0%). All patients were on maintenance hemodialysis via tunneled dialysis catheters at the time of fistula creation. The majority (31 patients, 63.3%) were dialyzing twice weekly.

The average pre-dialysis blood urea was 149.3 ± 71.1 mg/dL and serum creatinine 7.9 ± 2.8 mg/dL,the mean serum calcium was 7.8 ± 1.2 mg/dL, and mean phosphate was 6.0 ± 2.6 mg/dL.The mean hemoglobin was 9.0 ± 1.6 g/dL.

 Out of 49 AVFs, 41 (83.7%) were radio-cephalic fistulas constructed at the wrist (forearm AVFs). 22 were in the left arm and 19 in the right arm, as dictated by vessel suitability. Six patients (12.2%) received brachio-cephalic fistulas at the elbow (4 right, 2 left). One patient (2.0%) had a left brachio-basilic fistula and one (2.0%) had a left radio-median cubital vein fistula. The regional block provided adequate analgesia in every case; no block-related complications were observed. There were  no immediate surgical complications like significant bleeding requiring re-exploration. Primary technical success (presence of a palpable thrill at completion of the anastomosis) was achieved in all cases. Patients generally tolerated the procedure well, reporting comfort with only minimal sedation required.

At  follow up, out of 49 patients, 3 patients (6.1%) died within 3 months of the fistula creation and the fistula was never used (these cases were excluded from patency calculations). Among the remaining 46 patients, 33 AVFs were patent at 3 months, corresponding to a primary patency rate of 71.7%. 13 fistulae (28.3%) were not patent at 3 months. Of these 13 fistulae, 4 were primary failures and 9 were secondary failures . All 33 functional fistulae were in use after 6 months.

Creation of arteriovenous fistulas under ultrasound-guided supraclavicular brachial plexus block resulted in a 3-month primary patency of about 72% in our hemodialysis patients, with an 8.7% primary failure rate (a comparably better result). The access patency  results are comparable with international benchmarks and suggest that the use of regional anesthesia is a safe and effective technique that may enhance early fistula outcomes. The use of regional block also enhances the patient comfort during the procedure. The majority of patients in this study were able to successfully transition to catheter-free dialysis, reflecting the critical importance of a functional AVF