Departments of 1Radiology & Molecular Imaging and 2Medicine, Sultan Qaboos University Hospital, Muscat, Oman *Corresponding Author e-mail: drshoaib.rad@gmail.com سالمة ومضاعفات القساطري الوريدية املركزية النفقية املكممة اخلاصة بالديلزة الدموية منظور سريري وشعاعي من مركز واحد يف عمان رنا �سعيب حميد، اأنوبام كومار كاكاريا، �سيف اأحمد خان، �سجى حممد، را�سد ال�سكيتي، داود الريامي، يا�رس وعد اهلل املال عبد abstract: Objectives: This study aimed to assess the technical success, safety and immediate and delayed complications of double-lumen tunnelled cuffed central venous catheters (TVCs) at the Sultan Qaboos University Hospital (SQUH), Muscat, Oman. Methods: This retrospective study took place between January 2012 and October 2013. The clinical records and radiological data of all patients who underwent ultrasound- and fluoroscopy-guided TVC placement at SQUH during the study period were reviewed. Demographic data and information regarding catheter placement, technical success and peri- and post-procedure complications (such as catheter-related infections or thrombosis) were collected. Results: A total of 204 TVCs were placed in 161 patients. Of these, 68 were female (42.2%) and 93 were male (57.8%). The mean age of the patients was 54.4 ± 17.3 years. The most common reason for catheter placement was the initiation of dialysis (63.4%). A total of 203 procedures were technically successful (99.5%). The right internal jugular vein was the most common site of catheter placement (74.9%). Mild haemorrhage which resolved spontaneously occurred in 11 cases (5.4%). No other complications were observed. Subsequent follow-up data was available for 132 catheters (65.0%); of these, thrombosis-related catheter malfunction was observed in 22 cases (16.7%) and catheter-related infection in 29 cases (22.0%). Conclusion: Radiological-guided placement of tunnelled haemodialysis catheters can be performed safely with excellent technical success. The success rate of catheter insertion at SQUH was favourable in comparison with other studies reported in the literature. Keywords: Central Venous Catheters; Interventional Radiology; Thrombosis; Catheter-Related Infections; Renal Dialysis; Oman. امللخ�ص: الهدف: هدفت هذه الدرا�سة اإىل تقييم النجاح التقني وعن�رس ال�سالمة وامل�ساعفات الآنية واملتاأخرة للق�ساطري الوريدية املركزية الدرا�سة هذه الطريقة: عمان. يف م�سقط يف قابو�ض ال�سلطان جامعة م�ست�سفى يف الوريدية( )الق�ساطري املكممة النفقية اجلوف ثنائية ال�ستعرا�سية ال�ستعادية اأجريت ما بني �سهر 2012 و �سهر اكتوبر 2013. من خالل مراجعة ال�سجالت ال�رسيرية والبيانات ال�سعاعية جلميع ال�سعاعي والتنظري )ال�سونار( ال�سوتية فوق بالمواج الفح�ض جهاز من بتوجيه لهم وريدية ق�ساطري ق�ساطري و�سع مت الذين املر�سى )الفلورو�سكوبي( يف م�ست�سفى جامعة قابو�ض يف فرتة الدرا�سة. مت جمع ومراجعه كافه البيانات الدميوغرافية واملعلومات اخلا�سة بادخال الق�ساطري والنجاح التقني وم�ساعفات مابعد العملية )مثل النتانات املتعلقة بالق�سطار، والتخرث(. النتائج: خالل فرتة الدرا�سة مت ادخال 204 ق�سطارا وريديا يف 161 مري�سا. من بني هوؤلء املر�سى كان عدد الإناث 68 بن�سبة )%42.2( والذكور 93 بن�سبة )%57.8(. معدل اأعمار املر�سى كان يرتواح مابني 17.3 ± 54.4 �سنة. من خالل هذه الدرا�سة وجدنا اأن ال�سبب الأكرث �سيوعا لإدخال الق�سطار كان لغر�ض ابتداء الديلزة الدموية بن�سبه )%63.4(. 203 حالة )%99.5( اأجريت بتقنية ناجحة. الوريد الوداجي الداخلي الأمين كان املو�سع الأكرث �سيوعا لإدخال الق�سطار بن�سبة )%74.9(. حدوث نزف ب�سيط مع التوقف التلقائي �سجلت يف 11 حالة و بن�سبة )%5.4(. مل ت�ساهد اأي م�ساعفات اأخرى، معلومات عن املتابعة للم�ساعفات املتاأخرة كانت متوفرة من 132 ق�سطارا )%65.0(، من بينها 22 حالة )%16.7( عطل يف عمل الق�سطار ناجت عن التخرث، واإنتانات متعلقة بالق�سطار يف 29 حالة )%22.0(. اخلال�صة: و�سع ق�ساطري الديلزة الدموية النفقية بالتوجيه ال�سعاعي ميكن اإجراوؤه باأمان و بنجاح تقني ممتاز. معدل النجاح يف اإدخال الق�ساطري يف م�ست�سفى جامعة ال�سلطان قابو�ض كان مر�سيا مقارنة بالدرا�سات الأخرى امل�سجلة واملن�سورة. مفتاح الكلمات: ق�سطار وريدي مركزي؛ علم ال�سعة التداخلية؛ تخرث؛ اإنتانات متعلقة بالق�سطار؛ ديلزة دموية؛ عمان. Safety and Complications of Double-Lumen Tunnelled Cuffed Central Venous Dialysis Catheters Clinical and radiological perspective from a tertiary centre in Oman *Rana S. Hamid,1 Anupam K. Kakaria,1 Saif A. Khan,2 Saja Mohammed,2 Rashid Al-Sukaiti,1 Dawood Al-Riyami,2 Yasser W. Al-Mula Abed2 Sultan Qaboos University Med J, November 2015, Vol. 15, Iss. 4, pp. e501–506, Epub. 23 Nov 15 Submitted 12 Jan 15 Revision Req. 4 May 15; Revision Recd. 31 May 15 Accepted 25 Jun 15 clinical & basic research doi: 10.18295/squmj.2015.15.04.010 Safety and Complications of Double-Lumen Tunnelled Cuffed Central Venous Dialysis Catheters Clinical and radiological perspective from a tertiary centre in Oman e502 | SQU Medical Journal, November 2015, Volume 15, Issue 4 The provision of adequate haemodia-lysis depends on reliable access to large blood vessels capable of providing rapid blood flow.1 Currently, the three forms of long-term access most commonly used are the native arteriovenous (AV) fistula, synthetic graft and double-lumen tunnelled cuffed central venous catheter (TVC).2 First developed in 1987, these catheters are radio-opaque and made of soft silicone or polyurethane and are widely used to either provide bridging access before the creation and maturation of a high-flow AV fistula/graft or permanent access when a creation of a fistula/graft is not possible.3,4 At the Sultan Qaboos University Hospital (SQUH) in Muscat, Oman, TVCs are available in 12.5–14.5 French catheter sizes. They are placed in the distal superior vena cava and right atrium, usually using an internal jugular vein puncture after the creation of a subcutaneous tunnel superior to the breast along the lateral chest wall. Compared to a temporary dialysis catheter, TVCs have a softer polymer and therefore carry a reduced risk of subsequent vessel injury or erosion.5 Additionally, the larger diameter of the lumen allows increased blood flow during dialysis.5 They have a special antimicrobial cuff which serves to anchor the catheter in its tunnel using the in- growth of fibrous tissue. These catheters are normally placed by nephrologists or surgeons depending on local expertise. However, there is an increasing global trend for these catheters to be placed by interventional radiologists with very low incidences of procedure-related complications.2 Nevertheless, late complications—particularly infection and throm- bosis—remain problematic and can lead to catheter dysfunction and significant morbidity.6–8 To the best of the authors’ knowledge, no local data yet exist from Oman regarding the safety of radiological catheter placement and the prevalence of catheter-related complications. This study therefore aimed to assess the technical success, safety and immediate and delayed complications of ultrasound- and fluoroscopy-guided TVCs at SQUH. Methods This retrospective study was carried out between January 2012 and October 2013 at the Departments of Radiology & Molecular Imaging and Medicine at SQUH. All patients who underwent TVC placement during this 22-month period were included in the study. Demographic data for all patients were recorded on a structured form along with information about catheter placement, technical success, compli- cations of the catheter placement procedure and the development of any subsequent complications, such as catheter-related infections or thrombosis. All catheters were inserted by an interventional radiologist while the patient was in a supine position and under local anaesthesia. Coagulation parameters were checked before the procedure, including the prothrombin time, partial thromboplastin time and platelet count. A platelet count of ≥100 x 109/L and an international normalised ratio of <1.5 were considered acceptable. The procedures were performed using ultrasound and fluoroscopic guidance in the interventional radiology suite using a sterile technique. Ultrasonography was used to verify the patency of the internal jugular or femoral veins and to mark an appropriate puncture site. The vein was accessed with an 18-gauge needle with real-time ultrasound guidance and a 0.038-inch J-shaped flexible wire. Subsequently, a peel-away sheath was introduced over the guide wire following serial dilatation. After the patient had received lidocaine injected into either the upper chest or thigh (according to the puncture site), a subcutaneous tract was created using a tunnelling trocar. The catheter was attached to the threaded end of the trocar and pulled through the tunnel and out via the exit site. The TVC was then introduced through the peel-away sheath under fluoroscopy. The catheter hubs were flushed with heparinised saline solution and sterile caps were attached. A chest or pelvic radiograph was taken at the end of the procedure to confirm the position of the catheter tip. When required, the catheter was removed using a sterile technique. Using Advances in Knowledge - To the best of the authors’ knowledge, this study provides the first local data from Oman regarding the clinical safety of interventional radiological placement of double-lumen tunnelled cuffed central venous catheters (TVCs). This study presents the initial experience of this procedure at a tertiary care hospital. Application to Patient Care - As the number of patients requiring dialysis continues to grow, the creation and maintenance of haemodialysis access remains a vital healthcare issue worldwide. - This retrospective study assessed the safety and performance of TVCs at a tertiary care hospital in Oman to identify the nature and frequency of problems related to catheter insertion and usage. This will aid catheter placement and handling practices and ultimately improve patient care. Rana S. Hamid, Anupam K. Kakaria, Saif A. Khan, Saja Mohammed, Rashid Al-Sukaiti, Dawood Al-Riyami and Yasser W. Al-Mula Abed Clinical and Basic Research | e503 meticulous blunt dissection, the cuff was freed and the catheter was gently pulled out. Statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS), Version 20.0 (IBM Corp., Chicago, Illinois, USA). Ethical permission for this study was obtained from the Medical Research & Ethics Committee of the College of Medicine & Health Sciences at Sultan Qaboos University, Muscat, Oman (MREC #840). Results A total of 161 patients were referred to SQUH for TVC insertion during the study period. Of these, 68 were female (42.2%) and 93 were male (57.8%). The mean age of the patients was 54.39 ± 17.3 years (range: 13–90 years old). In total, 204 catheter placement procedures were performed on these patients; four patients had between 3–8 catheters inserted, 26 patients had two catheters inserted and 131 patients had one catheter inserted. The most common indication for catheter placement was the initiation of dialysis in newly diagnosed patients (63.4%) [Table 1]. Catheter placement procedures were successful in 203 cases (99.5%). Only one procedure failed; the catheter could not be placed due to bilateral internal jugular vein stenosis. The patient was restless and had respiratory distress due to pulmonary oedema. However, after his condition had stabilised, he returned the next day and a TVC was successfully placed in the right femoral vein. Of the successfully-placed catheters, 201 (99.0%) were placed during the first puncture. In the remaining two cases, the first puncture was unsuccessful and the catheters were placed during a second puncture within the same session. The right internal jugular vein was accessed in 152 cases (74.9%) while 32 catheters were placed through the left internal jugular vein (15.8%), 15 catheters were placed through the right femoral vein (7.4%) and four catheters were placed through the left femoral vein (2.0%). A total of 193 catheters (95.1%) were inserted in a satisfactory position with optimal placement and without any kinks in the catheter lumen and 10 catheters (4.9%) had suboptimal placement with kinks, malposition or both. The majority of the successful procedures (n = 193; 95.1%) were completed uneventfully without any complications. Mild bleeding at the skin entry site in the chest wall occurred during 11 procedures (5.4%); all of these resolved following manual compression for 10–15 minutes. These patients did not require any blood transfusions and were placed under observation to ensure their haemodynamic stability. There were no instances of haemo/pneumothorax, air embolisms or any other complications. After catheter placement, 114 patients (70.8%) continued dialysis outside of SQUH at other governmental facilities. The remaining 47 patients (29.2%) continued receiving dialysis at SQUH. Clinical follow-up information regarding catheter status was only available for 132 catheters placed in 100 patients [Figure 1]. The remaining 61 patients were lost to follow-up and no clinical records were therefore available for the remaining 71 catheters (35.0%). Of the patients who were lost to follow-up, 52 patients (85.3%) were receiving dialysis at other governmental facilities and nine patients (14.7%) had had their initial dialysis session at SQUH but did not return after being discharged. Out of the 132 catheters with follow- up data, 10 (7.6%) were accidentally pulled out after placement and three (2.3%) were found to have cuts. Table 1: Indications for double-lumen tunnelled cuffed central venous dialysis catheter insertion among patients at the Sultan Qaboos University Hospital, Muscat, Oman (N =161) Indication n (%) Dialysis initiation 102 (63.4) Replacement of temporary catheter 34 (21.1) Failed AV fistula/graft 17 (10.6) Failed transplant 4 (2.5) Replacement of blocked TVC 3 (1.9) Not available in records 1 (0.6) Total 161 (100.0) AV = arteriovenous; TVC = tunnelled cuffed central venous catheter. Figure 1: Catheter status at follow-up of double-lumen tunnelled cuffed central venous dialysis catheter catheters inserted among 161 patients at the Sultan Qaboos University Hospital, Muscat, Oman (N = 204). Follow-up information was only available for 132 catheters placed in 100 patients. Blood-borne and exit site infections were observed at follow-up in 29 cathe- ters (22.0%) placed in 22 patients. Thrombosis-related catheter malfunctions were observed in 22 cases (16.6%) leading to subsequent problems during dialysis. Safety and Complications of Double-Lumen Tunnelled Cuffed Central Venous Dialysis Catheters Clinical and radiological perspective from a tertiary centre in Oman e504 | SQU Medical Journal, November 2015, Volume 15, Issue 4 All of these catheters were not suitable for reuse and had to be replaced. Of the 132 catheters placed in the patients who were not lost to follow-up, thrombosis-related malfunctions were observed in 22 catheters (16.6%) leading to subsequent problems during dialysis. These 22 catheters were placed in 15 patients [Table 2]. The highest frequency of catheter-related thrombosis was seen in two patients. One of these patients had thrombosis in six out of eight catheters placed during the study period. As a result, this patient had multiple access problems, bilateral central venous stenosis and a thrombosed fistula. A routine thrombophilic screening test was negative. For the other patient, thrombosis was observed in three out of six catheters placed. This patient was in a hypercoagulable state and had a previous history of deep venous thrombosis of the lower limbs. He also had protein C and protein S deficiencies and there were pre-existing venous stenoses in the right internal jugular vein and the veins of right lower limb which were believed to be responsible for the recurrent thrombosis. The stenoses in the lower limb veins were treated by angioplasty. Among the thrombosed catheters, the patency of five catheters was successfully restored via the injection of thrombolytic agents into the catheter lumen. However, 17 catheters were still non-functioning after this treatment and were removed. Table 3: Catheter-related infections of double-lumen tunnelled cuffed central venous dialysis catheter procedures among patients at the Sultan Qaboos University Hospital, Muscat, Oman (N = 22) Catheters placed per patient Infected catheters per patient Route of infection Causative organism 6 2 Blood-borne Exit site Staphylococcus aureus Staphylococcus aureus 4 3 Blood-borne Blood-borne Blood-borne Pseudomonas Enterobacter Enterobacter 2 2 Blood-borne Blood-borne Staphylococcus aureus Pseudomonas 2 2 Blood-borne Blood-borne Acinetobacter No growth 2 2 Blood-borne Both routes Staphylococcus aureus Staphylococcus aureus 2 2 Both routes Both routes Staphylococcus aureus Staphylococcus aureus 2 1 Blood-borne Pseudomonas 2 1 Both routes Acinetobacter 2 1 Blood-borne Staphylococcus aureus 1 1 Exit site Staphylococcus aureus 1 1 Blood-borne Staphylococcus aureus 1 1 Exit site Staphylococcus aureus 1 1 Blood-borne Acinetobacter 1 1 Blood-borne Staphylococcus aureus 1 1 Blood-borne Staphylococcus aureus 1 1 Both routes Klebsiella 1 1 Both routes Proteus mirabilis 1 1 Blood-borne Enterococcus 1 1 Blood-borne Staphylococcus aureus 1 1 Both routes Staphylococcus aureus 1 1 Blood-borne Staphylococcus epidermidis 1 1 Exit site Staphylococcus aureus Table 2: Thrombosis-related malfunctions of double- lumen tunnelled cuffed central venous dialysis catheter procedures among patients at the Sultan Qaboos University Hospital, Muscat, Oman (N =15) Catheters placed per patient Thrombosed catheters per patient 8 6 6 3 2 1 2 1 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Rana S. Hamid, Anupam K. Kakaria, Saif A. Khan, Saja Mohammed, Rashid Al-Sukaiti, Dawood Al-Riyami and Yasser W. Al-Mula Abed Clinical and Basic Research | e505 Infection was observed at follow-up in 29 catheters (22.0%) placed in 22 patients [Table 3]. Two of the patients with infected catheters also had thrombosis but it was not possible to determine which condition occurred first. Of the infections, there were 18 cases of blood-borne infections (62.1%), four cases (13.8%) of exit site infections in the skin of the chest and seven cases (24.1%) of both blood-borne and exit site infections. One elderly male patient had blood-borne infections which occurred in three out of four catheters placed during the study period. He was diabetic and hypertensive and had coronary artery disease. His dialysis sessions were held at another facility outside of SQUH. Four patients had catheters placed twice during the study period, with all of these catheters developing infections. Culture results indicated that the most common bacteria causing infections was Staphylococcus aureus in 16 cases (55.2%), followed by bacteria of the Acinetobacter and Pseudomonas genera which were each seen in three cases (10.3% each). Infections in five catheters (17.2%) were successfully treated with antibiotics while 24 infections (82.8%) did not respond well to antibiotics and persisted, leading to the catheters being removed. Discussion Dialysis as a modality of renal replacement therapy is generally required in patients with acute kidney injury or end-stage renal disease. Haemodialysis accounts for 89% of all patients who receive dialysis, with the rest receiving peritoneal dialysis.9 Although the AV fistula is the preferred mode of access for haemodialysis, TVCs can help patients awaiting maturation of an AV fistula or those for whom an AV fistula is not possible. The success rate of catheter insertion in the current study was favourable in comparison with other studies reported in the literature.10,11 This may be because all of the procedures were performed using ultrasound and fluoroscopic guidance, which is known to increase the success rate of insertion.11,12 Additio- nally, the procedure was very safe for the majority of patients with a very low procedure-related immediate complication rate. All of the immediate complications were related to local bleeding and could be controlled by manual compression. None of the patients required additional procedures for management and there were no cases of haemo/pneumothorax or air embo- lism detected. These findings are similar to those reported elsewhere.10,11 Catheter-related thrombosis in the form of a fibrin sheath or a thrombus in the catheter is a frequent complication of indwelling catheters and accounts for up to 40.0% of catheter failures.2 In the present study, the rate of thrombus-related catheter malfunctions (16.7%) was lower than those reported in the literature.2,4 In particular, one patient had eight catheters inserted of which six thrombosed and an AV fistula which also thrombosed without ever being used for dialysis. Although a routine thrombophilic screen was negative, it is likely that the patient was suffering from an unknown thrombophilic disorder. Another patient had a previous history of deep venous thrombosis and protein C and protein S deficiencies which probably contributed to the multiple catheter failures. However, although the overall thrombosis- related catheter failure rate was lower than previously reported, and several affected catheters were salvaged by intracatheter thrombolysis, the majority of the affected catheters had to be removed. Another serious complication with significant morbidity and mortality in patients undergoing haemodialysis is catheter-related infection. The risk of bacteraemia with a cuffed tunnelled catheter is nearly 10 times that of an AV fistula.13 The overall infection rate in the current study (21.9%) was much lower than that reported in the literature; catheter- related infection rates of 54.0% have been reported, with up to two-thirds of catheters requiring removal.2,3 Despite the low catheter-related infection rate, the majority of infected catheters in the current study required removal and very few infections were cleared satisfactorily with antibiotics. Cuffed tunnelled catheters provide a temporary alternative to AV fistulae for haemodialysis patients. Nevertheless, while patient acceptance is particularly high with catheters as no needles are required for the purposes of the dialysis, significant complications and failure rates remain higher than for AV fistulae.14 Further research into catheter materials and construction is needed to reduce the rates of these complications and prolong the useful life span of catheters. Conclusion Radiology-guided placement of tunnelled haemodia- lysis catheters at SQUH was performed safely with excellent technical success (99.5%). Mild haemorrhage which resolved spontaneously was the only procedure- related immediate complication (5.4%). Additionally, low rates of subsequent thrombosis-related catheter malfunction (16.7%) and catheter-related infection (22.0%) were observed. These rates compared favour- ably with the international literature. Safety and Complications of Double-Lumen Tunnelled Cuffed Central Venous Dialysis Catheters Clinical and radiological perspective from a tertiary centre in Oman e506 | SQU Medical Journal, November 2015, Volume 15, Issue 4 c o n f l i c t o f i n t e r e s t The authors declare no conflicts of interest. References 1. Butterly DW, Schwab SJ. Catheter access for hemodialysis: An overview. Semin Dial 2001; 14:411–15. doi: 10.1046/j.1525- 139x.2001.00104.x. 2. Trerotola SO. Hemodialysis catheter placement and manage- ment. Radiology 2000; 215:651–8. doi: 10.1148/radiology. 215.3.r00jn23651. 3. Schwab SJ, Buller GL, McCann RL, Bollinger RR, Stickel DL. Prospective evaluation of a Dacron cuffed hemodialysis catheter for prolonged use. Am J Kidney Dis 1988; 11:166–9. doi: 10.1016/S0272-6386(88)80206-3. 4. Moss AH, McLaughlin MM, Lempert KD, Holley JL. Use of a silicone catheter with a Dacron cuff for short-term vascular access. 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