Clinical Trial: Regional Anesthesia for Arteriovenous Fistula

Study Status: Suspended
Recruit Status: Suspended
Study Type: Interventional

Official Title: Effect of Sympathetic Blockade on the Success and Survival of Arteriovenous Fistula

Brief Summary: Once kidney function goes below 10 to 15 percent of normal, dialysis treatments or a kidney transplant are necessary to sustain life. One type of dialysis is hemodialysis which cleans blood by removing it from the body and passing it through a dialyzer, or artificial kidney. To maximize the amount of blood cleansed during hemodialysis treatments, there should be continuous high volumes of blood flow. A fistula used for hemodialysis is a direct connection of an artery to a vein. Once an arteriovenous fistula (AVF) is created it is a natural part of the body. This is the preferred type of access because once the fistula properly matures and gets bigger and stronger; it provides an access with good blood flow that can last for decades. After the fistula is surgically created, it can take weeks to months before the fistula matures and is ready to be used for hemodialysis. There have been surgical factors identified; one of them being the anesthetic used which may cause a fistula not to survive. This study will look at comparing 3 anesthetic techniques: axillary block (AB) versus stellate ganglion (SGB) block+local anesthetic versus local anesthetic (LA).

Detailed Summary:

To allow for chronic hemodialysis (HD), patients with end-stage renal disease (ESRD) require permanent vascular access in the form of either arteriovenous graft (AVG) or arteriovenous fistula (AVF). The latter option is the preferred form of vascular access given the lower rate of thrombosis, fewer interventions required, longer survival for vascular access and lower rate of infection as compared to AVG (1). Despite this, earlier reports have suggested that the initial failure rate of AVF approximates to 25% (2). A permanent vascular access is considered adequate when it has sufficient size (i.e. greater than 0.6 cm) for easy cannulation and a flow rate of approximately 600 mL/min for dialysis (1, 3). However, postoperative AVF blood flow may be compromised by arterial vasospasm and sympathetic activity from surgical manipulations (4, 5). Inadequate flow rate in the postoperative period can result in early thrombus formation at the fistula and, if left untreated, can lead to permanent loss of vascular access(6). Over the years, researchers have identified a number of patient and surgical factors that may influence the success and long-term survival of AVF, and recent evidence suggests that the choice of anesthetic techniques may play a significant role (7).

Vascular access surgery is usually conducted under either a) general anesthesia (GA), b) local anesthetics (LA) infiltrations with sedations, or c) regional anesthesia in the form of brachial plexus block (BPB). GA, while providing both anesthesia and analgesia, can present a challenge for maintaining intraoperative hemodynamic stability as patients with ESRD often have other significant comorbidities. LA infiltrations, though offering simplicity, does not provide motor blockade and patient movement can be a surgical challenge. LA requires multiple injections during the case. BPB thus presents as an attractive option a
Sponsor: McMaster University

Current Primary Outcome: Arteriovenous fistula flow [ Time Frame: 1 hour post-operatively ]

Arteriovenous fistula in mL/min


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Change in limb temperature pre-anesthetic and post-anesthetics [ Time Frame: 1 hour post-operatively ]
  • Duration of intraoperative procedure [ Time Frame: 3 hours post-operatively ]
  • Rate of conversion to general anesthetic [ Time Frame: 1 day post-operatively ]
  • Anesthesia-related adverse events [ Time Frame: 1 day post-operatively ]
  • Maturation time [ Time Frame: 2 months post-operatively ]
  • Patient Satisfaction [ Time Frame: 2 months post-operatively ]


Original Secondary Outcome: Same as current

Information By: McMaster University

Dates:
Date Received: November 11, 2014
Date Started: December 2015
Date Completion: December 2017
Last Updated: September 14, 2016
Last Verified: September 2016