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the kdoqi recommended order of preference for placement of fistulae in patients with chronic kidney disease should be a forearm ( radiocephalic ) primary fistula , an elbow ( brachiocephalic ) primary fistula , a transposed brachial - basilic vein fistula , followed by arteriovenous graft ( avg ) of synthetic or biological material . in patients with unfavourable anatomy for radiocephalic fistula ,
if the median antecubital vein or median basilic vein has a favorable anatomy ( > 2.5 mm and connected to median cephalic vein ) , it can be used to construct a brachiocephalic arteriovenous fistula ( avf ) with reverse flow in that vein which has no valve .
our hypothesis is that this technique even with poor caliber of cephalic vein can increase the flow in the cephalic vein that is sufficient for maturation and cannulation for hemodialysis .
 smooth loop is created from brachial artery to cephalic vein through the antecubital vein and by ligating the distal cephalic vein , perforating vein , and the median vein of forearm .
this technical variant has already been described by pantea and bengulescu   without results data .
we did a retrospective analysis of patients who underwent brachiocephalic avf creation through median antecubital vein in our institute between september 2014 and august 2015 .
data collected include each patient 's preoperative evaluation , operative procedure , patency , failures , and complications .
several studies support the 2.5-mm vein and 2.0 mm artery diameter threshold for successful creation of a fistula .
the patients with following criteria were taken up for brachiocephalic avf using the median antecubital vein . 

the anatomy of cephalic vein and radial artery at the wrist is unsuitable for avf creationcephalic vein diameter is < 2.5 mmeither median antecubital vein / median basilic vein is more than 2.5 mm in diameter andbrachial artery diameter at elbow more than 2 mm . 
 
the anatomy of cephalic vein and radial artery at the wrist is unsuitable for avf creation cephalic vein diameter is < 2.5 mm either median antecubital vein / median basilic vein is more than 2.5 mm in diameter and brachial artery diameter at elbow more than 2 mm . primary failure was defined as an avf that did not mature or thrombosed before the first successful cannulation for hemodialysis treatment .
the definition includes ( 1 ) inadequate maturation , ( 2 ) early thrombosis , ( 3 ) failure of the first cannulation , and ( 4 ) other complications such as ischemia or infection .
secondary failure was defined as irreversible failure of the avf after it has been successfully used for hemodialysis . under local anesthesia ,
a transverse skin incision was made at about 1 cm above the elbow crease , centering with the brachial artery pulsation .
a side to side anastamosis between brachial artery and median basilic vein or median antecubital vein ( mav ) was done using 60 prolene .
the upper part of the median basilic vein was ligated to change the side to side anastomosis into a side to end anastomosis .
ligation of the perforating vein and venous tributaries from the forearm to the loop created is done to limit the risk of high - flow fistula [ figures 1 and 2 ] .
operative anatomy of the cubital fossa brachiocephalic arteriovenous fistula through median antecubital vein at the elbow a  back wall first 
technique is used in all patients , similar to the method described by tellis et al .
this involves initiating the suture in the mid portion of the back wall and using a running suture technique , closing the back wall from the inside of the anastamosis and then completing each corner .
under local anesthesia , a transverse skin incision was made at about 1 cm above the elbow crease , centering with the brachial artery pulsation . the median antecubital vein ( or median basilic vein )
a side to side anastamosis between brachial artery and median basilic vein or median antecubital vein ( mav ) was done using 60 prolene .
the upper part of the median basilic vein was ligated to change the side to side anastomosis into a side to end anastomosis .
ligation of the perforating vein and venous tributaries from the forearm to the loop created is done to limit the risk of high - flow fistula [ figures 1 and 2 ] .
operative anatomy of the cubital fossa brachiocephalic arteriovenous fistula through median antecubital vein at the elbow a  back wall first 
technique is used in all patients , similar to the method described by tellis et al .
this involves initiating the suture in the mid portion of the back wall and using a running suture technique , closing the back wall from the inside of the anastamosis and then completing each corner .
between september 2014 and august 2015 , a total of 68 patients underwent arteriovenous ( av ) access surgery .
the most common site was brachiocephalic avf through a median antecubital vein ( 38.2% ) followed by the radiocephalic avf at the wrist ( 25% ) .
the other sites were brachiocephalic avf at the elbow ( 23.5% ) , radio cephalic avf at mid forearm ( 2.9% ) , proximal radial artery / median vein of forearm avf ( 2.9% ) , and brachiobasilic avf with transposition ( 1.5% ) .
only three patients ( 4.5% ) underwent av graft surgery as they had no choice for native avf .
lower limb avf between posterior tibial and saphenous vein was done in one patient ( 1.5% ) due to poor caliber of upper limb veins and unaffordability of the patient for avg .
the 26 patients with brachiocephalic avf through median antecubital vein were included for further analysis .
the mean age of patients was 50.78  11.27 years with a range of 3067 years .
the co - morbidities include diabetes mellitus in 8 ( 30.76% ) , hypertension in 22 ( 84.61% ) , and malignancy in 2 ( 7.69% ) patients .
the mean preoperative diameter of artery and vein were 4.89 mm and 2.85 mm , respectively .
the mean cephalic vein diameter before the surgery and 2 months after surgery was 1.95 mm and 7.18 mm respectively .
primary patency rate at 6 months in our series was 88.46% comparable to radiocephalic and brachiocephalic fistula [ table 1 ] .
complications include aneurysm and thrombosis ( 7.69% ) , edema ( 19.23% ) , hematoma ( 11.53% ) , and wound infection ( 3.8% ) [ table 1 ] . during follow - up , 4 ( 15.38% )
patients died with functioning fistula , 6 ( 23.07% ) patients were lost to follow - up , and 13 ( 50% ) patients were continuing dialysis with brachiocephalic avf through median antecubital vein .
as the life expectancy of hemodialysis patients have improved over years , many patients require multiple vascular access procedures over their lifetime .
furthermore , the long term patency and complications of avg are worse compared to avf . hence , it is prudent to preserve as many vessels possible and start using the distal vessels . in such scenario ,
the brachiocephalic avf through median antecubital vein provides an opportunity to sustain hemodialysis . in patients with unsuitable cephalic vein at the forearm and elbow , the options are brachiobasilic fistula with transposition and av grafts either autologous or synthetic . these types of vascular access have few disadvantages , i.e. , difficult to construct , the requirement of a second procedure for transposition , costs of graft , and associated infection
. however , the presence of multiple interconnected veins with anatomic variations in the cubital fossa allows for avf creation with other veins such as median basilic vein , mav and median vein of forearm .
the advantages include avoiding the need for superficialization of the basilic vein in arm . in none of our patients with brachiocephalic avf through median antecubital vein ,
the main basilic vein is preserved and can be used for future avf creation . ligating the tributaries from forearm to the loop created including the perforating vein will prevent the development of high - flow and venous hypertension , and will increase the flow in the cephalic vein .
the demographic profile of our series is similar to other studies with diabetes as the most common cause of end - stage renal disease and the mean age of around 50 years .
the most common site of avf in our study was using brachial artery ( 63.24% ) followed by a radial artery ( 30.88% ) .
the strategies followed by us were using median basilic vein with caliber ( > 2.5 mm ) adequate enough for anastamosis , larger arteriotomy of 810 mm , and side to side anastamosis which allowed for establishing increased blood flow across the anastamosis to aid maturation . though the mean preoperative caliber of cephalic vein was less than recommended 2.5 mm , using the above strategies resulted in dilatation of venous segment to 7.18 mm and mean flow rate of 1415 ml / min after maturation .
kdoqi recommends venous segment diameter of at least 6 mm and flows rate of at least 600 ml / min for successful cannulation . though we created a larger arteriotomy to enhance flow across fistula , none of our patients developed vascular steal phenomenon .
all our patients underwent side to side anastamosis with proximal vein ligation and ligation of tributaries from forearm to the loop created .
the advantages of creation of a side - to - side anastamosis are technical simplicity and uniform wall shear stress profile which would lead to reduced rate of intimal hyperplasia . in a study by o'banion et al .
side to side anastamosis with distal vein ligation has been found to be superior to end to side anastamosis in radiocephalic fistula in terms of early thrombosis , 6-month primary patency and cannulation rates
. primary failure rate ( 3.87% ) was much lesser compared to rates in the current literature ( 1530% ) which includes both distal and proximal fistulas .
however , the primary failure rates of distal fistulas are higher than proximal fistulas due their small caliber and lower flow rates .
pramila and biradar reported primary failure rates of 7% and 22.8% in brachial and radial arteries respectively .
the primary failure rates were radiocephalic avf ( 39% ) , brachiocephalic avf ( 17% ) , and brachiobasilic avf ( 18% ) in a study by gonzalez et al . our primary failure rate ( 3.87% ) of brachiocephalic avf through median antecubital vein is comparable to the above studies .
the complications of avf surgery in our study was similar to that reported by checherita et al .
to conclude , our study supports the use of brachiocephalic avf creation through median antecubital vein in patients with favorable veins configurations at the elbow based on adequate blood flow rates , venous segment dilatation , low primary failure rates , and complication rate equivalent to those of other native fistulas . based on our findings ,
we prefer native avf before creating av grafts by utilizing the cubital fossa venous connections along with its variations . there are no conflicts of interest .
in patients unsuitable for radiocephalic fistula creation , the next option is brachiocephalic fistula . in such patients 
 , we exploited the venous interconnections in the cubital fossa for median cubital vein - brachiocephalic arteriovenous fistula ( avf ) creation . in this article , we describe our experience in the creation of such technical variant of the brachiocephalic fistula avf , its success and associated complications . 
 a retrospective review of such avf created between september 2014 and august 2015 was done . 
 the data collected included demographics , co - morbidities , basic disease , operative details , patency , complications , and mortality . 
 a total of 68 vascular access surgeries were done which included 26 ( 38.2% ) brachiocephalic avf using the median antecubital vein . 
 the mean cephalic vein diameter and mean flow rate were 7.18 mm and 1415 ml / min , respectively 2 months after fistula creation . 
 the primary and secondary failure rates were 3.87% and 7.69% respectively . 
 complications included aneurysm ( 7.69% ) , edema ( 19.23% ) , hematoma ( 11.53% ) , and wound infection ( 3.8% ) . 
 using reverse flow in the median antecubital vein is a safe and simple way to perform brachiocephalic avf before brachiobasilic avf and grafts .