Tahir Doughman

Axillary-axillary loop graft for hemodialysis access

Background Vascular access in hemodialysis patients can be challenging especially in those with failed primary, secondary and/or tertiary procedures. We present a technique which utilizes the axillary artery and vein to fashion a synthetic loop graft. Method A synthetic arteriovenous loop graft is formed using the axillary artery and vein under general anesthesia following pre-operative contrast venograms. Discussion This method allows the use of the upper arm vessels, thereby preserving vessels in the legs; it also facilitates immediate access for dialysis. Conclusion The axillary-axillary loop graft is a valuable salvage option in patients with complex vascular access.

The great saphenous vein for central venous access and haemodialysis

BACKGROUND Utilising an open surgical technique the Great Saphenous vein in the proximal thigh can be used for the insertion of central venous catheters for haemodialysis. This approach is safe and efficacious, and may be performed under local or general anaesthesia. This technique is of particular importance in patients requiring vascular access for haemodialysis in whom the upper central veins are stenosed and the femoral vessels are not amenable to percutaneous cannulation. METHODS The Great saphenous vein is exposed via a surgical incision in the thigh. The central venous catheter is then inserted and advanced until in the desired position, as confirmed on fluoroscopy. RESULTS Seven Great saphenous catheters were placed over a period of six months. All catheters insertions were technical successes with completion of at least one dialysis session. Primary patency rates were 57%, 49%, 23% at 30, 60 and 90 days respectively. CONCLUSION The great saphenous vein offers an additional site for the insertion of central venous catheters. These data demonstrate equivalence in patency between this novel technique and percutaneous femoral vein cannulation.

A successful scheme for reducing waiting times for arteriovenous fistula formation.

PURPOSE In a bid to reduce waiting times for arteriovenous fistula (AVF) formation we introduced a scheme whereby nephrologists were able to place patients directly on the waiting list for surgery. This study evaluated the quality of these direct referrals and assessed the reduction in waiting times. METHODS Fifty consecutive patients referred directly to the waiting list were compared with 50 patients placed on the waiting list after being assessed in our vascular access clinic. RESULTS Forty-nine patients from the direct group and 47 patients from the clinic group underwent surgery. In the direct group 39 patients (80%) underwent the same procedure as they had been originally listed for, compared with 39 patients (83%) in the clinic group (p=0.80). A fistula suitable for needling was created in 37 patients (76%) of the direct group and 38 patients (81%) of the clinic group (p=0.62). The median wait from referral to surgery in the direct group was significantly lower than in the clinic group (62 vs.141 days; p<0.0001). CONCLUSION This study demonstrates that nephrologists are able to effectively assess select patients for AVF formation. This significantly reduces waiting times for surgery, without an increase in cancelled operations, or a reduction in technical success.

External iliac artery dissection causing early renal transplant dysfunction

External iliac artery dissection after kidney transplantation is a rare, catastrophic but potentially reversible complication. Treatment which may save both the transplant and the patient requires clinical suspicion, timely imaging, and prompt intervention. This case report describes successful diagnosis of this complication and surgical intervention which saved the kidney and safeguarded blood supply to the patients leg.

The Use of 16S Ribosomal RNA PCR to Investigate Donor Derived Transport Fluid Infections in Patients Undergoing Renal Transplantation: A Retrosepctive Audit of 36 Deceased Donors

Introduction 16S ribosomal RNA (rRNA) gene polymerase chair reaction (PCR) is emerging as a high yield molecular method for the detection and identification of bacterial pathogens in clinical specimens with a high suspicion for infection. This is advantageous in the detection of pathogens which may have gone undetected in routine laboratory cultures. Methods Transport fluid obtained from 36 deceased donors was assessed by two different methods. The fluid was sent for bacterial culture, which is the current gold standard, and in addition further assessment via 16S PCR was performed for comparison. Results The average donor age was 46.7 years. 58.3% were DBD donors. 38% of donors were being treated for infection. 52% of all donors received a dose or course of antibiotics within 72 hours prior to retrieval. 48% of donors grew a bacterial pathogen on standard bacterial culture; however 7% were thought to be secondary to contamination. 16S RNA PCR was performed on 62% of fluid samples where a positive standard bacterial culture was obtained. 16S PCR detected 21% of bacterial pathogens in samples with a positive standard culture. Discussion We identified two issues to address, 1. 16S PCR was not consistently performed on all fluid samples which had a positive laboratory culture 2. the 16S PCR bacterial detection rate in the cohort with a positive culture was comparitively low. In some instances it was not possible to identify organisms to species level due to the presence of multiple species and variants of microorganism. There is a need to standardise the 16S PCR technique on transport fluids by addressing the presence of potential inhibitors in these samples and by improving the design of primers. Conclusion There is limited understanding of the use of 16S PCR for detection of infection in cadaveric donors. 16S PCR has the potential to improve yield of pathogens and help tailor antibiotic therapy of the patient in line with antimicrobial stewardship. However, there is a need to standardise the technique for optimal results in solid organ donor derived infections.