Reliable vascular access is essential for effective maintenance hemodialysis. Native arteriovenous fistulas and arteriovenous grafts are generally preferred for durable access when appropriate, but tunneled cuffed hemodialysis catheters remain indispensable for patients who require immediate or intermediate-duration dialysis access, whose definitive access is immature or has failed, or whose vascular anatomy and clinical circumstances preclude timely creation of an arteriovenous access. Contemporary KDOQI guidance emphasizes an individualized “right access, right patient, right time” approach rather than an inflexible hierarchy of access types [1]. Tunneled hemodialysis catheters can be used immediately and avoid repeated temporary-catheter exchanges; however, their invasive position within the central venous system exposes patients to mechanical and infectious complications. Immediate adverse events may include inadvertent arterial puncture, hematoma, bleeding, catheter malposition, arrhythmia, pneumothorax, hemothorax, or air embolism. Delayed complications include catheter-related bloodstream infection (CRBSI), exit-site or tunnel infection, intraluminal thrombosis, fibrin-sheath formation, central venous stenosis, migration, and inadequate dialysis blood flow [2–4]. Image guidance has changed the safety profile of central venous access. Real-time ultrasonography permits identification of the vein, confirmation of patency, recognition of anatomic variation, and direct visualization of needle entry. Fluoroscopy provides confirmation of guidewire trajectory, catheter course, and final tip position. KDOQI recommends ultrasound guidance for tunneled cuffed central venous catheter insertion and supports imaging confirmation of appropriate tip position [1]. Modern series using routine ultrasound have reported very low rates of pneumothorax and hemothorax [5]. The right internal jugular vein is commonly preferred because of its relatively straight course toward the superior vena cava and right atrium. Left-sided access may require a more angulated intrathoracic course and can be associated with greater mechanical stress or altered flow characteristics. Nevertheless, site selection must take into account previous vascular access, central venous patency, future access planning, and patient-specific anatomy [1,3]. Indian studies demonstrate that tunneled catheter outcomes vary according to case mix, operator experience, infection-prevention practice, catheter-care protocols, and duration of exposure. Banerjee et al. reported 3.74 CRBSI episodes per 1,000 catheter-days in an Indian cohort of 159 tunneled cuffed catheters [6]. More recently, Konnepati et al. reported 100% technical success in a randomized Indian study of ultrasound-guided tunneled dialysis catheter placement performed with or without fluoroscopic assistance [7]. These data highlight the value of structured procedural audit and catheter-day-based outcome reporting. The burden of chronic kidney disease and the logistical complexity of accessing specialized vascular procedures may be particularly important in geographically remote regions. Establishing a local image-guided vascular-access service can potentially reduce referral delays and improve continuity of care, but the early outcomes of such services require systematic evaluation. The present study was designed to evaluate 100 consecutive tunneled hemodialysis catheter insertions performed by a single surgeon in the Department of Cardiothoracic and Vascular Surgery (CTVS), Tomo Riba Institute of Health and Medical Sciences (TRIHMS), Naharlagun (Itanagar), Arunachal Pradesh. The primary objectives were to describe technical success and immediate procedural safety. Secondary objectives were to evaluate catheter-related infection, dysfunction, thrombosis, dwell time, catheter survival, and final catheter disposition during the first 18 months of a newly established vascular access service.

Study design and setting This single-center retrospective observational cohort study was conducted in the Department of Cardiothoracic and Vascular Surgery (CTVS), Tomo Riba Institute of Health and Medical Sciences (TRIHMS), Naharlagun (Itanagar), Arunachal Pradesh, India, over 18 months from 1 January 2025 to 30 June 2026. The study was reported in accordance with STROBE principles [10]. Study population and sampling The cohort comprised 100 consecutive tunneled cuffed hemodialysis catheter (Permcath) insertion episodes performed by a single CTVS surgeon. Some patients underwent more than one tunneled catheter insertion; each insertion was analyzed as a separate catheter episode. All eligible procedures during the study period were included. Eligibility criteria Inclusion criteria were: (1) tunneled cuffed hemodialysis catheter insertion at TRIHMS during the study period; (2) procedure performed by the designated CTVS surgeon; and (3) use of real-time ultrasound-guided venous puncture with fluoroscopic guidance for catheter advancement and tip positioning. Temporary non-tunneled dialysis catheters, isolated catheter-removal procedures, and tunneled catheter insertions performed by other operators were excluded. Indications for catheter insertion Indications were classified from operative and clinical records as hemodialysis requirement without mature definitive vascular access, failed or thrombosed arteriovenous fistula/graft, delayed maturation of arteriovenous access, vessels unsuitable for definitive access, replacement after previous catheter dysfunction or infection, or another documented indication. Preprocedural assessment Available records were reviewed for age, sex, underlying kidney disease, dialysis status, diabetes mellitus, hypertension, prior temporary dialysis catheterization, previous arteriovenous access, and previous access failure. Preprocedural hemoglobin, platelet count, coagulation parameters, and other investigations were considered according to clinical indication. Previous central venous catheterization, known central venous thrombosis or stenosis, and future vascular-access planning were documented where available. Catheter insertion technique All procedures were performed under aseptic conditions using real-time ultrasonography for venous access and fluoroscopy for guidewire advancement, catheter course, and final catheter-tip positioning. The target vein was evaluated for patency, diameter, compressibility, and relationship to adjacent arterial structures. The right internal jugular vein was preferred when clinically and anatomically suitable, while alternative venous routes were selected according to vascular patency and prior access history. Following skin preparation, sterile draping, and local anesthesia, the target vein was punctured under direct ultrasound visualization. A guidewire was advanced and its central venous course confirmed fluoroscopically. After tract preparation and subcutaneous tunneling, the tunneled cuffed dialysis catheter was introduced using an appropriate peel-away sheath/introducer technique. Catheter length was selected to obtain a satisfactory central venous/right atrial tip position while avoiding excessive catheter redundancy or kinking. Both lumens were checked for free aspiration and flushing before the catheter was secured and dressed. Data collection Data were abstracted retrospectively from operative records, inpatient and outpatient notes, dialysis records, microbiology reports, and available follow-up documentation. Variables included baseline demographic and clinical characteristics, indication for catheter placement, insertion site, side, number of puncture attempts when recorded, technical success, immediate adverse events, catheter dysfunction, infection, thrombosis, catheter dwell time, and final catheter disposition. Outcome definitions Technical success was defined as successful placement of the tunneled catheter into the intended central venous position with satisfactory aspiration and flushing of both lumens and ability to use the catheter for hemodialysis. Immediate complications were events occurring during the procedure or immediate postprocedural period, including arterial puncture, significant bleeding, hematoma, catheter malposition, arrhythmia, pneumothorax, hemothorax, air embolism, or another procedure-related adverse event. Catheter dysfunction was defined clinically as inability to deliver the prescribed extracorporeal blood flow or adequate dialysis without corrective intervention or prolongation of treatment. Documented causes included intraluminal thrombosis, fibrin sheath, catheter-tip migration/malposition, kinking, or other mechanical obstruction [1,2]. Catheter-related infection included exit-site infection, tunnel infection, and bloodstream infection clinically attributed to the tunneled dialysis catheter. Where microbiological data were available, CRBSI episodes were recorded separately and incidence was expressed per 1,000 catheter-days. Catheter-associated thrombosis included documented intraluminal catheter thrombosis, internal jugular or central venous thrombosis, or clinically significant fibrin-sheath-related obstruction. Final catheter outcomes were classified as catheter functioning at last follow-up, removal following successful arteriovenous access use, removal/exchange because of infection, dysfunction, thrombosis, accidental dislodgement/damage, renal recovery, renal transplantation, death with functioning catheter, or another reason. Follow-up and catheter survival Follow-up was calculated from catheter insertion until removal or exchange, death, transfer/loss to follow-up, last documented catheter use, or the end of the observation period. Catheter dwell time was expressed in days. Event incidence was expressed per 1,000 catheter-days where appropriate. Catheter survival was summarized at 30, 90, 180, and 365 days. Statistical analysis Continuous variables were summarized as mean ± standard deviation when approximately normally distributed and as median with interquartile range when skewed. Categorical variables were summarized as frequencies and percentages. Wilson 95% confidence intervals were calculated for selected proportions. Incidence rates were calculated as the number of events divided by total catheter-days and multiplied by 1,000. Catheter survival was estimated using the Kaplan–Meier method. Because the study was primarily descriptive, no multivariable modeling was undertaken.

Baseline characteristics Between 1 January 2025 and 30 June 2026, 100 consecutive tunneled hemodialysis catheter insertion episodes were analyzed. Mean age at insertion was 54.8 ± 13.9 years (range 19–82 years). Sixty-two episodes (62%) occurred in male patients and 38 (38%) in female patients. Hypertension was present in 84%, diabetes mellitus in 46%, and both diabetes and hypertension in 39%. At catheter insertion, 39% were incident hemodialysis episodes and 61% were maintenance hemodialysis episodes. A previous temporary dialysis catheter had been used in 61%, while 36% had a previous arteriovenous fistula or graft. The primary renal disease was categorized as diabetic kidney disease in 38%, hypertensive kidney disease in 28%, chronic glomerular disease in 12%, chronic kidney disease of undetermined etiology in 14%, obstructive nephropathy in 5%, and other causes in 3%. Table 1. Baseline characteristics of the study cohort Characteristic Value Total catheter insertion episodes 100 Age, years, mean ± SD 54.8 ± 13.9 Age range 19–82 years Male 62 (62%) Female 38 (38%) Diabetes mellitus 46 (46%) Hypertension 84 (84%) Diabetes with hypertension 39 (39%) Incident hemodialysis 39 (39%) Maintenance hemodialysis 61 (61%) Previous temporary dialysis catheter 61 (61%) Previous AV fistula/graft 36 (36%) Previous failed vascular access 24 (24%) Indications for tunneled catheter placement The most frequent indication was requirement for hemodialysis in the absence of mature definitive vascular access (41%). Failed or thrombosed pre-existing arteriovenous access accounted for 24%, delayed maturation of an arteriovenous fistula for 15%, and unsuitable vessels for immediate definitive access for 8%. Replacement following prior catheter dysfunction or infection accounted for 9%, while other documented indications accounted for 3%. Table 2. Indications for tunneled hemodialysis catheter placement Indication n (%) No mature definitive vascular access 41 (41%) Failed/thrombosed AV fistula or graft 24 (24%) Delayed maturation of AV fistula 15 (15%) Unsuitable vessels for definitive access 8 (8%) Previous catheter dysfunction/infection 9 (9%) Other indications 3 (3%) Total 100 (100%) Procedural characteristics and technical success The right internal jugular vein was used in 88 procedures (88%), the left internal jugular vein in 10 (10%), and an alternative access site in 2 (2%). All 100 procedures used real-time ultrasound-guided venous puncture and fluoroscopic guidance. Technical success was achieved in 99 of 100 episodes (99%; 95% CI 94.6–99.8). First-attempt venous cannulation was achieved in 91%, catheter-tip repositioning was required in 4%, and 94% of procedures were completed without an immediate complication. Table 3. Catheter placement and procedural characteristics Procedural variable n (%) Right internal jugular vein 88 (88%) Left internal jugular vein 10 (10%) Alternative access site 2 (2%) Ultrasound-guided venous puncture 100 (100%) Fluoroscopic guidance 100 (100%) Technical success 99 (99%) First-attempt venous cannulation 91 (91%) Catheter-tip repositioning required 4 (4%) No immediate procedural complication 94 (94%) Immediate procedural complications Immediate procedure-related complications occurred in 6 procedures (6%; 95% CI 2.8–12.5). Minor bleeding or exit-site oozing occurred in 3%, localized hematoma in 2%, and inadvertent arterial puncture in 1%. Catheter malposition requiring fluoroscopic correction occurred in 2%, and transient procedure-related arrhythmia in 1%. No pneumothorax, hemothorax, air embolism, or procedure-related death was recorded. Because more than one minor event could occur in an individual procedure, event counts were not mutually exclusive. Delayed catheter-related complications The 99 successfully placed catheters contributed 15,420 catheter-days of observation. Catheter dysfunction occurred in 15 catheters (15.2%; 0.97 events per 1,000 catheter-days), catheter-related bloodstream infection occurred in 11 catheters (11.1%) with 12 documented episodes (0.78 episodes per 1,000 catheter-days), and catheter-associated thrombosis occurred in 6 catheters (6.1%; 0.39 events per 1,000 catheter-days). Exit-site infection occurred in 5 catheters (5.1%), tunnel infection in 2 (2.0%), clinically documented central venous thrombosis/stenosis in 3 (3.0%), and catheter migration or accidental dislodgement in 3 (3.0%). Table 4. Immediate complications (n=100) and delayed catheter-related complications (n=99) Complication n (%) / episodes Rate per 1,000 catheter-days Minor bleeding/exit-site oozing 3 (3%) — Hematoma 2 (2%) — Arterial puncture 1 (1%) — Pneumothorax 0 — Hemothorax 0 — Catheter malposition 2 (2%) — Transient arrhythmia 1 (1%) — Catheter dysfunction 15 (15.2%) 0.97 CRBSI 11 catheters (11.1%); 12 episodes 0.78 Exit-site infection 5 (5.1%) 0.32 Tunnel infection 2 (2.0%) 0.13 Catheter-associated thrombosis 6 (6.1%) 0.39 Central venous thrombosis/stenosis 3 (3.0%) 0.19 Migration/dislodgement 3 (3.0%) 0.19 Catheter-related bloodstream infection and microbiology Twelve CRBSI episodes occurred in 11 catheters during 15,420 catheter-days, corresponding to 0.78 episodes per 1,000 catheter-days. Gram-positive organisms accounted for 7 of 12 episodes (58.3%), Gram-negative organisms for 4 (33.3%), and one episode (8.3%) was polymicrobial. Staphylococcus aureus accounted for 4 episodes (33.3%), coagulase-negative staphylococci for 3 (25.0%), Klebsiella pneumoniae for 2 (16.7%), Escherichia coli for 1 (8.3%), Pseudomonas aeruginosa for 1 (8.3%), and mixed bacterial growth for 1 (8.3%). Catheter removal because of infection occurred in 10 catheters, while 2 infection episodes were managed without immediate catheter removal. Catheter dysfunction and thrombotic events Catheter dysfunction occurred in 15 catheters, with a median time to documented dysfunction of 112 days. Recorded causes were intraluminal thrombosis in 6, suspected fibrin-sheath-related dysfunction in 4, catheter-tip migration or malposition in 3, and kinking or another mechanical cause in 2. Thrombolytic therapy was used in 7 cases, catheter manipulation or repositioning in 4, and catheter exchange or removal for persistent dysfunction in 8. These interventions were not mutually exclusive. Catheter dwell time, survival, and final outcomes Among the 99 successfully placed catheters, median catheter dwell time was 146 days (IQR 86–228 days). Estimated catheter survival was 97% at 30 days, 89% at 90 days, 72% at 180 days, and 44% at 365 days. At the end of follow-up, 26 catheters remained functional and in clinical use. Thirty-one were removed after successful transition to a functioning arteriovenous fistula or graft. Infection accounted for removal in 10 catheters, persistent dysfunction in 8, thrombosis in 4, and accidental dislodgement or damage in 3. Three catheters were removed after renal recovery and one after renal transplantation. Eleven patients died during follow-up with a functioning catheter, while 2 catheters had other final outcomes. One insertion was technically unsuccessful. Table 5. Final disposition of the 100 catheter insertion episodes Outcome n (%) Catheter functioning at last follow-up 26 (26%) Removed following successful AVF/AVG use 31 (31%) Removed because of infection 10 (10%) Removed/exchanged because of dysfunction 8 (8%) Removed because of thrombosis 4 (4%) Accidental dislodgement/damage 3 (3%) Renal recovery 3 (3%) Renal transplantation 1 (1%) Death with functioning catheter 11 (11%) Other 2 (2%) Technical insertion failure/no catheter placed 1 (1%) Total 100 (100%)

This retrospective cohort describes the initial performance of a newly established vascular-access service at TRIHMS through 100 consecutive tunneled hemodialysis catheter insertion episodes performed by a single CTVS surgeon over 18 months. Technical success was 99% and immediate complications occurred in 6% of procedures. Among the 99 successfully placed catheters, dysfunction occurred in 15.2%, catheter-associated thrombosis in 6.1%, and CRBSI in 11.1%, corresponding to 0.78 CRBSI episodes per 1,000 catheter-days. Median catheter dwell time was 146 days. A principal feature of the service was procedural standardization. All catheters were inserted by one surgeon using real-time ultrasonography for venous access and fluoroscopy for catheter advancement and final positioning. KDOQI guidance supports ultrasound-guided tunneled catheter insertion and imaging confirmation of appropriate catheter-tip position because image guidance improves successful placement and reduces inadvertent arterial puncture and other insertion complications [1]. Agarwal et al. similarly emphasized that ultrasound, fluoroscopy, adequate operator training, checklist use, and barrier precautions improve the safety of tunneled dialysis catheter placement [4]. The 99% technical success rate is consistent with the high success expected from image-guided placement. Konnepati et al. reported 100% technical success among 149 tunneled dialysis catheter insertions in a randomized study from North India, with 86.5% successful on the first attempt [7]. The first-attempt cannulation proportion in the present cohort was 91%. Differences between studies may reflect operator experience, vascular anatomy, previous catheterization, and definitions of first-attempt success. Major mechanical complications were uncommon. The absence of pneumothorax and hemothorax is directionally consistent with the large series of Aurshina et al., who reviewed 1,766 ultrasound-guided tunneled hemodialysis catheter placements and reported no postprocedural pneumothorax or hemothorax [5]. These observations support the routine use of real-time ultrasound, particularly for internal jugular venous puncture. The right internal jugular vein accounted for 88% of placements. This is consistent with its favorable anatomic course and with recommendations that generally prefer the right internal jugular route when suitable [1,3]. Martin et al. identified left internal jugular insertion as a risk factor for tunneled catheter-related bloodstream infection in their cohort, although infection risk is multifactorial and depends strongly on catheter care, patient comorbidity, duration of use, and local practice [8]. Infectious complications are among the most clinically important limitations of tunneled catheters. Banerjee et al. reported a CRBSI rate of 3.74 episodes per 1,000 catheter-days in an Indian prospective cohort of 159 tunneled cuffed catheters [6]. In the present cohort, the CRBSI rate was 0.78 episodes per 1,000 catheter-days. Reporting infection per 1,000 catheter-days is preferable to percentages alone because it accounts for differences in exposure time; however, comparisons across studies should consider differences in patient mix, catheter-care protocols, event definitions, and follow-up. The microbiological profile was dominated by Gram-positive organisms, especially Staphylococcus aureus and coagulase-negative staphylococci, together accounting for 7 of 12 CRBSI episodes. Gram-negative organisms accounted for 4 episodes and one episode was polymicrobial. This distribution is consistent with the recognized contribution of skin flora to catheter colonization and bloodstream infection. Catheter dysfunction occurred in 15.2% of successfully placed catheters, a frequency similar to the one-year malfunction risk of approximately 15% reported by Poinen et al. in a Canadian observational cohort of 1,041 patients initiating maintenance hemodialysis with a tunneled catheter [9]. Their study also reported approximately 9% bacteremia and 2% central venous stenosis at one year [9]. Such comparisons are useful for contextualization, but differences in patient selection, follow-up, access-care protocols, and event definitions should be recognized. Thrombosis and fibrin-sheath-related dysfunction accounted for most mechanical failures. These mechanisms are well recognized in the tunneled catheter literature and may lead to inadequate blood flow, repeated thrombolytic exposure, catheter exchange, or loss of access [2]. Central venous thrombosis and stenosis are particularly important because they may compromise future arteriovenous access options and therefore warrant careful surveillance. The median catheter dwell time of 146 days suggests that tunneled catheters often served as intermediate rather than permanent access. Thirty-one of the 100 catheter insertion episodes resulted in catheter removal after successful transition to an arteriovenous fistula or graft. This is clinically desirable when the catheter is being used as a bridge to more durable access. Conversely, a substantial proportion of catheters remained in use or were lost because of infection, dysfunction, thrombosis, mortality, or other clinical events, demonstrating the continuing morbidity associated with catheter dependence. The setting of the study is relevant. Arunachal Pradesh presents geographic and logistical challenges that may limit rapid access to specialized vascular procedures. A local, image-guided vascular-access service at a tertiary institution such as TRIHMS has the potential to reduce external referrals, shorten delays to dialysis access, and permit standardized follow-up. A single-surgeon model may also support quality improvement during the early phase of service development because operator-related technical variability is minimized. Prospective catheter registries with standardized infection definitions, microbiology data, cause-specific catheter failure, and linkage to subsequent arteriovenous access would allow more detailed long-term outcome assessment. Strengths The study design has several strengths: inclusion of 100 consecutive procedures over a defined period; a single-surgeon model that minimizes interoperator variability; universal use of real-time ultrasound and fluoroscopy; evaluation of both immediate procedural safety and delayed catheter outcomes; and the use of catheter-day-based incidence measures, which facilitates comparison with other cohorts. Limitations The retrospective design makes the study dependent on completeness of existing documentation. A single-center cohort of 100 procedures has limited power for uncommon outcomes and multivariable risk-factor analysis. The single-surgeon design improves internal procedural consistency but may limit generalizability to other operators or specialties. Follow-up duration differs among catheters inserted at different points during the 18-month study period. Post-insertion catheter care, especially when dialysis occurs outside the primary institution, may influence infection and dysfunction independently of placement technique.

In this retrospective cohort of 100 consecutive tunneled hemodialysis catheter insertion episodes performed between 1 January 2025 and 30 June 2026 at Tomo Riba Institute of Health and Medical Sciences, a standardized single-surgeon technique using ultrasound-guided venous access and fluoroscopic catheter placement achieved a 99% technical success rate with few major immediate mechanical complications. Among 99 successfully placed catheters followed for 15,420 catheter-days, catheter dysfunction occurred in 15.2%, thrombosis in 6.1%, and CRBSI in 11.1%, with a CRBSI incidence of 0.78 episodes per 1,000 catheter-days. Median catheter dwell time was 146 days, and 31 catheter episodes were followed by transition to functional arteriovenous access

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