Preoperative Antibiotics for Dialysis Access Surgery: Are They Necessary?

BACKGROUND: Current guidelines recommend preoperative antibiotics in all vascular surgery cases. However, we hypothesize that patients undergoing arteriovenous fistula (AVF) and arteriovenous graft (AVG) creation have low rates of postoperative surgical site infection (SSI) and that preoperative antibiotic prophylaxis in these patients may not be necessary. METHODS: This is a retrospective review of all patients who underwent AVF and AVG creation from November 2014 through July of 2016 at a single institution. At our institution, preoperative antibiotic use is surgeon dependent. Patients who received preoperative antibiotics were compared with those who did not. The primary outcome measured was the development of postoperative SSI. RESULTS: There were 304 patients identified and 294 patients with 30 day postoperative follow-up. Of the 294 patients, 23 (7.8%) received an AVG, and 271 (92.2%) received an AVF. There were 244 (83%) patients who received preoperative antibiotics and 50 (17%) who did not. Overall, there were 2 (0.68%) SSIs identified. Both patients with postoperative SSI underwent AVF creation and received preoperative antibiotics. There was no statistically significant difference in SSI rate between antibiotic and nonantibiotic groups (P = 1.0), and no difference when comparing patients that received AVG (0%) and AVF (0.73%) (P = 1.0). CONCLUSIONS: The rate for postoperative SSI following hemodialysis access surgery is very low both for patients undergoing AVF and AVG. Furthermore, there was no difference in SSI rate between antibiotic and nonantibiotic groups. Given these findings, we conclude that preoperative antibiotics for AVF creation may not be necessary.

Factors Associated with Early Thrombosis after Arteriovenous Fistula Creation.

BACKGROUND: Arteriovenous fistulas (AVF) are the preferred modality for hemodialysis access. Early thrombosis hampers development of a working AVF. We endeavored to determine the incidence and identify factors associated with early thrombosis of AVF and to determine salvage rates following thrombosis, at a high-volume hemodialysis access center. METHODS: Retrospective review of autologous AVF was created between November 2014 and July 2016 at a single center. Early thrombosis was defined as thrombosis that occurred within 30 days of surgery. RESULTS: There were 291 AVFs. The median age was 54.7 years, and 192 patients (66%) were male. Early postoperative AVF thrombosis was noted in 5 (1.7%) cases. Factors associated with early thrombosis on univariate analysis included previous access surgery (P = 0.02) and absence of a good intraoperative thrill (P = 0.006). Intraoperative protamine use trended toward significance (P = 0.06). Factors that were not significant included gender, diabetes, dialysis at time of surgery, fistula configuration, and systemic heparin use. None of the thrombosed fistulas were salvaged. CONCLUSIONS: Early thrombosis is a relatively rare complication of AVF creation at a high-volume center. Previous access surgery and absence of good thrill at conclusion of the procedure are associated with early thrombosis.

Ultrasound Vein and Artery Mapping by General Surgery Residents During Initial Consult Can Decrease Time to Dialysis Access Creation.

BACKGROUND: Formal preoperative ultrasound (US) mapping of vascular anatomy by radiology is recommended before hemodialysis access surgery. We hypothesized that US performed by general surgery residents in place of formal US would decrease the time from initial consult to creation of dialysis access without affecting patient outcomes. METHODS: This is a retrospective review of all patients who underwent dialysis access surgery from November 2014 to July 2016 and received preoperative upper extremity US vein and artery evaluation by either radiology or general surgery residents. The primary endpoints were days from initial consult to dialysis access creation, rate of arteriovenous fistula (AVF) creation, fistula maturation, and 1-year primary assisted patency. RESULTS: Of 242 patients, 167 (69%) had formal US, and 75 (31%) had only a resident US. The resident US group had 100% AVF creation compared with the formal US group with 92.2% AVF creation (P = 0.01). There was no difference between the groups in rate of fistula maturation (P = 0.1) and 1-year assisted patency (P = 0.9). Of the resident US 90.7% occurred in the outpatient setting. On multivariable analysis controlling for outpatient consult, the average time to the operating room was 13.7 days longer for the formal US group in the outpatient setting (P = 0.0006). CONCLUSIONS: Ultrasound vein and artery evaluation at the time of the initial consult by general surgery residents can decrease the time to dialysis access creation by bypassing the need for formal US with a higher rate of AVF creation and no difference in fistula maturation or 1-year primary assisted patency.

Predictors of Steal in Hemodialysis Access.

Pathological steal is an uncommon but devastating complication after the creation of arteriovenous access for hemodialysis. In this study, we sought to assess predictors of clinically significant steal syndrome and to further evaluate the outcome of differing surgical treatment approaches. A retrospective analysis was performed of 282 consecutive patients undergoing hemodialysis access at a single center from November 2014 to April 2016. Adequate follow-up to assess for the development of steal was obtained in 237 patients. One hundred and fifty-seven (66%) patients were male, 152 (64%) Hispanic, and 164 (69%) had diabetes. Forty-three (18%) had prior access procedures. Autologous fistula was created in 218 patients (92%). Pathologic steal occurred in 15 patients (6.7%). On univariate analysis, significant predictors of steal included female sex [P = 0.03, odds ratio (OR) = 3.3, CI [1.1-9]), no systemic heparin at operation (P = 0.02, OR = 5.0, CI [1.4-10]), use of angiotensin-converting enzyme inhibitor (P = 0.003, OR = 5.6, CI [1.7-18.6]), and increased vein size (3.1 vs 4.1 mm P = 0.01). Twelve patients had steal managed with an intervention, but only one patient received distal revascularization. Furthermore, we identify key predictors of clinically significant steal syndrome while demonstrating that distal revascularization and/or fistula ligation are rarely indicated treatment modalities.