This study was approved by the institutional review board. Between January 2015 and October 2018, 296 patients (180 males and 116 females with mean age of 53.2 years ± 11.7 years ranging from 38 to 65 years) were presented to interventional radiology unit at our university hospital for transhepatic hemodialysis catheter insertion. Causes of the end-stage renal disease were hypertension in 99 patients, diabetes mellitus in 50 patients, renal stones in 28 patients, urinary tract infection in 29 patients, congenital abnormality in 18 patients, primary glomerulonephritis in 15 patients, and unknown causes in 57 patients. All cases were chronic dialysis patients who have thrombosed classic routes of catheterization (internal jugular, subclavian, and femoral veins bilaterally) as well as non-functioning/thrombosed AV fistulas or grafts.
Patients with uncorrectable coagulopathy (platelets count less than 70,000 or INR more than 1.5), patients on long-term anticoagulants, significant abdominal ascites, concurrent active infection, and cirrhotic liver disease patients were excluded from our study.
All patients were subjected to history taking and duplex examinations to verify thrombosis of conventional sites for hemodialysis catheters, abdominal sonography, and duplex to exclude ascites; delineate, and assess both hepatic parenchyma as well as hepatic veins. Lastly, laboratory tests including platelets count and coagulation profile were performed.
The procedure was simply explained to the patients. Then a written consent was obtained from all patients included in the study.
Interventional radiology specialist with 10-year experience in interventional radiology performed the procedures. Another interventional radiology specialist with 5-years experience assisted him.
All procedures were performed in interventional radiology unit at university hospital.
Technique
Single dose of broad spectrum intra-venous antibiotic (Cefazolin 1g) was administrated 2 h before the procedure. Patients lie in supine position, and the right side of the skin of abdomen and lower chest was sterilized with Betadine® Solution (Povidone-iodine, 10%). All patients were monitored for their vital signs including pulse, blood pressure, and oxygen saturation during the whole time of procedure. The procedure was done under local anesthesia with injection of 10 ml lidocaine. Some patients were given mild sedation (midazolam 0.03 mg/kg intravenous) to alleviate their anxiety. The chosen hepatic veins, right in 128 patients (Figs. 1 and 2), middle in 110 patients (Figs. 3 and 4), and left in 58 patients (Fig. 5) were accessed by a 16-G angiocath under ultrasound guidance. We used either intercostal or subcostal approaches for right and middle hepatic veins and subxyphoid approach for left hepatic vein. We aim to enter the hepatic veins rather than IVC directly to allow a longer intra-vascular tract thus reducing the possibility of migration out of the vessels. Entrance of the hepatic veins is confirmed by injection of diluted contrast media (Ultravist® 300 (iopromide) till become visualized. Then under fluoroscopic guidance (TOSHIBA, Infx-8000v), a hydrophilic guide wire (0.035 in.) was introduced through the angiocath in hepatic vein, and secured upwards in superior vena cava (SVC) and right atrium in 234 patients or downwards in inferior vena cava in 60 patients, a split catheter was applied in 2 cases where one end of the catheter was within the right atrium and the other end within the IVC (Fig. 6). Subcutaneous tunnel was formed anteroinferiorly and then the catheter was inserted over the wire through the peel away sheath. Catheters used in our study were Hickman hemodialysis/apheresis 13.5-F., round dual-lumen radiopaque silicone catheter, luer lock adapters, and SureCuff tissue in growth cuff, 2.0 mm in lumens, 36 cm in overall length, 19 cm in tip-to-cuff length (Bard Acess System, Salt Lake City, Utah), or Ash Split Cath (Medcomp, Harleyville, Pa) in different lengths. The catheter tip was positioned opposite the third intercostal space to be within the right atrium. In other cases that have catheter tip within IVC, it was positioned opposite or above the level of L1 vertebra. The venotomy site was closed using silk sutures (2/0). Both lumens of the catheter were flushed with heparin and aspirated to ensure patency. Post procedural images were obtained to confirm the correct positioning. The dialysis catheter can be used directly after its insertion.
The average procedure time was 55 min ranged between 40 and 100 min.
Post-procedure care
Pain killers were prescribed and taken on demand. Most of patients respond to oral analgesic (non steroidal anti-inflammatory drugs). We have to give stronger intra-venous analgesics (pelfergan and tramal) in few cases. All cases were admitted at the same day of the procedure. Cases without complication were routinely discharged 24 h after the procedure. Sonographic follow-up 24-h post-procedure was performed before discharge to exclude any complications specially hepatic subcapsular hematoma and intra-peritoneal bleeding.
Follow-up of catheter for its patency and function was done via documentation by the nephrologists at dialysis centers and communication with the interventional radiology specialist. Follow-up was performed by monitoring the catheter dialysis rate in each session. Also, inspection of catheter exit was done to exclude infection. Blood cultures obtained from the catheter site was done if catheter-related sepsis is suspected. All complications were monitored and documented. Catheters which are no longer functioning or cases with suspected catheter-related complications were sent again to the interventional radiology unit for reassessment and revision if indicated.
Catheter exchange through same primary access site was indicated and performed 315 times in seventy-two patients. Causes of catheter exchange were catheter thrombosis, sepsis, and migration.
Definitions
All the terms used in the study were defined in light of the “Reporting Standards for Central Venous Access” definitions of Society of Interventional Radiology (SIR) as follows: Technical success is defined as introduction into the venous system with the tip positioned in the preferred location and with adequate catheter function (300 mL/min). Primary device service interval is defined as the number of catheter-days from initial placement until removal. Secondary device service interval is defined as the number of catheter-days after device replacement using the same access site. Mean time catheter in situ is defined as the cumulative catheter-days divided by the cumulative number of catheters in the entire study population. Mean cumulative duration of catheter in situ is defined as the cummulative catheter-days divided by the number of patients.
Mean duration of function of catheters, mean of primary device service (function), mean of secondary device service (function) interval, mean time catheter in situ and mean cumulative duration of catheter in situ were calculated using Kaplan–Meier method.