title: Distal revascularization and interval ligation (DRIL) procedure requires a long bypass for optimal inflow.
abstract: BACKGROUND
  Distal revascularization and interval ligation (DRIL) is commonly used to treat ischemic steal syndrome caused by arteriovenous hemodialysis access and has been associated with good outcomes. However, the literature lacks technical details of a successful intervention. We tested the hypothesis that a brachial-level arteriovenous fistula (AVF) generates a zone of low arterial blood pressure in the brachial artery near the AVF origin.
  
  
  METHODS
  We identified patients with ischemic steal syndrome caused by an AVF originating from the brachial artery level who were eligible for the DRIL procedure. All patients were studied with invasive pressure monitoring in the brachial artery at the time of digital subtraction angiography. We measured systolic, diastolic and mean arterial blood pressure at 5 cm intervals from a point in the arterial circulation 5 cm distal to the origin of the AVF and continuing proximally into the subclavian artery.
  
  
  RESULTS
  Our series involved 10 patients with a mean age of 66.5 (range 53-81) years. Four patients were women and 8 had diabetes. All patients had grade 3 ischemic steal syndrome with ischemic rest pain and/or ischemic tissue loss. Mean systolic, diastolic and arterial pressures increased from the level of the AVF until central pressures were reached. Systolic blood pressure was significantly lower than central blood pressure until a level 20-25 cm proximal to the AVF.
  
  
  CONCLUSIONS
  The benefits of the DRIL procedure in alleviating ischemic steal syndrome associated with hemodialysis access are best achieved with a DRIL bypass for which inflow originates at least 20-25 cm proximal to the origin of the AVF.
authors.affiliation: From the Department of Surgery, University of Saskatchewan, Regina Qu'Appelle Health Region, Regina, Sask.
authors.forename: David
authors.initials: D
authors.lastname: Kopriva
authors.affiliation: From the Department of Surgery, University of Saskatchewan, Regina Qu'Appelle Health Region, Regina, Sask.
authors.forename: Donald J
authors.initials: DJ
authors.lastname: McCarville
authors.affiliation: From the Department of Surgery, University of Saskatchewan, Regina Qu'Appelle Health Region, Regina, Sask.
authors.forename: Sanjay M
authors.initials: SM
authors.lastname: Jacob
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001132:Arm / Q000098:blood supply*; D001166:Arteriovenous Shunt, Surgical / Q000009:adverse effects*; D001794:Blood Pressure; D001916:Brachial Artery / Q000601:surgery*; D002415:Cats; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007511:Ischemia / Q000209:etiology* / Q000601:surgery*; D008026:Ligation; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow; D006435:Renal Dialysis; D015424:Reperfusion; D016896:Treatment Outcome; D062666:Vascular Access Devices