Peritoneal dialysis (PD) is a well-established renal replacement therapy for patients with end-stage renal disease (ESRD). The success of peritoneal dialysis as renal replacement therapy depends on a well-functioning peritoneal catheter [1].

Complications associated with PD catheters (PDC) significantly contribute to patient morbidity, leading to interruptions in treatment and decreased dialysis efficacy [2][3]. These complications often cause the need to transfer to hemodialysis, hospitalization, and surgical procedures.

The success and longevity of PD are frequently challenged by both infectious and non-infectious complications [1,2].

Infections, particularly peritonitis, are widely recognized as major causes of technique failure and morbidity in PD patients [1][2][4][5]. Peritonitis not only compromises immediate health but also has long-term implications on the functionality and survival of the PD catheter. Prevention and effective treatment of peritonitis is critical to reduce technique failure and the need for catheter removal [4].

Non-infectious complications, although less frequently discussed, also pose significant challenges to the survival of PD catheters and overall patient outcomes [3][6]. These include mechanical issues such as outflow failure, catheter migration, and omental wrapping, as well as hernias, hemoperitoneum, and dialysate leaks [7]. Such complications can lead to recurrent interventions, increased healthcare costs, and reduced adherence to PD therapy [8].

This study aims to review the peritoneal dialysis catheter (PDC) outcomes at our center and to identify factors that significantly influence catheter longevity, providing insights that can enhance management strategies for maintaining PD efficacy.

We conducted a retrospective study including all PD patients who had their first PD catheter implanted between the 1st of August 2012 and the 31st of July 2022 in our institution.

All catheters were double-cuffed, pig-tailed Tenckhoff catheters. Most PD catheters were placed surgically by two surgeons (mini-laparotomy or laparoscopy). A minority of catheters (n=8) were placed percutaneously by one nephrologist, using the Seldinger technique.

The medical records of the 146 patients included in the study were reviewed for their demographic and clinical characteristics, including age, gender, underlying etiology of ESRD, comorbidities, and prior abdominal surgeries. During the follow-up, we collected data regarding infectious and non-infectious complications. Early complications were defined as those developing within 30 days after PDC insertion, whereas late complications were defined as those developing after 30 days.

The primary endpoint was PD catheter failure, defined as the removal of the PD catheter due to catheter-related complications. The catheter-related complications were divided into infectious and non-infectious. PD catheter infectious complications included exit-site infections (ESI), tunnel infections (TI), and peritonitis. The non-infectious complications included outflow failure due to catheter migration/ mal-positioning, omental wrap, catheter leakage, post-incisional hernia, hemoperitoneum, and pleuro-peritoneal shunt.

The catheter survivor was defined as a patient who had maintained PD by the end of follow-up or had PDC removal due to issues unrelated to PDC, such as patient death, kidney transplantation, patient demand, inadequate PD, or improved residual renal function.

Statistical analyses were performed using IBM SPSS, version 28 (SPSS, Chicago, IL, USA). Categorical variables are expressed as numbers and percentages, and continuous variables are expressed as mean ± standard deviation. The Pearson χ2 test or Fisher’s exact test was used to analyze categorical variables. For continuous variables, the means were compared using the Student’s t-test. Kaplan-Meier curves were used to estimate catheter survival. Cox regression model was used to identify factors that were independently associated with catheter survival. A p-value of less than 0.05 was considered statistically significant.

The present study enrolled 146 incident PD patients who received first-time PDC insertion at our center over a ten-year period. The 1-year, 2-year and 3-year PD catheter survival was 80.2%, 72.4% and 61.6%, respectively. This represents a better PD catheter outcome compared to what has been reported in some earlier studies [9,10]. A prospective study conducted on 72 patients who had their first peritoneal dialysis catheters surgically inserted between 1992 and 1995, re- ported 1-year, 2-year, and 3-year survival rates of 62.5%, 41.5%, and 36%, respectively [9]. The higher catheter failure rate observed in this study is likely attributed to the significant number of persistent peritonitis leading to the removal of functioning PD catheters. In a larger trial that included 203 patients and ran from 1982 to 1995, one-year and three-year survival rates for the first catheters were reported to be 75% and 37%, respectively [10].

Conversely, our PDC survival rate is lower than the one demonstrated in two more recent studies [6,11]. Singh et al. conducted a retrospective study on 315 patients who had their first PD catheter placed between January 2001 and September 2009, showing a 1-year, 2-year, and 3-year PD catheter survival rate of 92.9%, 91.9%, and 91.1% respectively [6]. The significantly lower number of peritonitis described in this study (39.5% of patients with at least one episode of PDP vs 51.4% in our population) may have contributed to this difference in survival rates. Kang et al reported a 1-year and 5-year survival of 97.1–97.8% and 87.0–91.1%, respectively [11]. The total number of patients with one or more PDP events was comparable to ours (40-50.0% vs 51.4%), however, only a small proportion of patients with infectious complications required catheter removal. Additionally, only a minority of patients with mechanical complications had their PDC removed [11]. Together, these two factors may explain the difference in PDC survival rates. Notably, in our study, a significant proportion of complications, especially non-infectious ones, resulted in catheter removal/ replacement. This could indicate suboptimal salvage maneuvers, such as catheter recovery attempts using fluoroscopic guidance.

PD catheter-related non-infectious complications were the single covariate that significantly reduced the catheter’s survival time. Each PDC-related non-infectious complication increased the risk of catheter failure more than 2 times (Hazard ratio 2.53). Singh et al described similar results, with PDC-related non-infectious complications as the only variable independently associated with catheter survival (Hazard ratio 22.467) [6]. In our study, approximately half the cases of outflow failure required catheter removal, largely contributing to the impact of non-infectious complications on PDC outcomes. The omental wrapping was a very common cause of catheter dysfunction in our population (22.4%). Some authors suggest performing an omentectomy during catheter placement to avoid wrapping and the need for secondary interventions [3][12]. In fact, in a study from Mexico that included 235 PD patients, omentectomy was found to have a protective effect against catheter dysfunction and removal, probably due to the reduced rate of obstruction from omental wrapping [3].

Peritonitis has been widely recognized as a leading cause of catheter and technique failure in PD patients, contributing to catheter loss and increased morbidity [1][2][5]. In a large study involving 473 CAPD patients, the primary cause of PD catheter removal was peritonitis [5]. It is suggested that the formation of biofilm on the PD catheter is an obstacle to the continuation of PD in these cases. A different team of researchers examined the impact of 579 episodes of peritonitis on PD catheters and described that only 12% of the peritonitis episodes led to the removal of the PD catheter [13]. Notably, this study demonstrated that concurrent tunnel or exit-site infections increased the likelihood of catheter loss [13]. Nevertheless, Singh et al. showed that PD-related peritonitis was not significantly associated with PD catheter survival [6]6. In our study, patients with peritonitis were more likely to have PDC-associated removal (p=0.017). However, in the multivariate analysis, peritoneal infections were not significantly associated with PD catheter survival. The most likely explanation is that the negative impact on the catheter outcome may have been mitigated by quick and effective treatment of the PDP. Additionally, the greater impact of non-infectious complications on PDC survival may have minimized the effect of peritonitis on PDC survival time. Although our study highlights the significant impact of non-infectious complications on catheter survival, educating patients on recognizing the signs and symptoms of both infectious and non-infectious complications is crucial for ensuring timely medical intervention and potentially preventing the need for catheter removal or replacement.

None of the other demographic (age, gender) or clinical characteristics (diabetic status, obesity, previous abdominal surgeries, method of catheter insertion) were found to be independently associated with the PD catheter’s survival.

It has been suggested that previous abdominal surgeries increase the risk of PD catheter mechanical complications and could impact their survival [14]. In our study, although only a small percentage of patients (11.6%) had a history of prior abdominal surgery, we found no significant association between these surgeries and PD catheter survival. Our results align with the findings of previous studies [3][6][15]. In the studies by both Singh et al. and Martinez et al., previous abdominal procedures had no discernible impact on catheter survival [3][6].

Decisions regarding the choice of dialysis modality are influenced by various factors, including social, economic, and medical considerations, such as the patient’s comorbidities [16]. Obesity is often considered a relative contraindication for peritoneal dialysis. However, a recent study involving 231 PD patients evaluated the effect of patient weight on PD catheter survival and found that obesity did not increase complications or shorten PDC survival, regardless of the operative technique used [17]. Tiong et al. analyzed several factors related to catheter dysfunction and found that patients with a history of diabetes and glomerulonephritis had a higher probability (OR: 3.24; 6.52, respectively) of early complications [14]. Conversely, more recent studies found no association between comorbidities, such as diabetes, and PD catheter survival [3][6], suggesting that comorbidities should not affect patient selection for PD. Similarly, we did not observe any relationship between pre-existing medical conditions, including obesity and diabetes mellitus, and PDC survival.

We found no significant association between the method of catheter insertion and catheter survival time, although the small number of patients in each group may limit the generalizability of these results. Additionally, there was no association between the catheter insertion technique and the development of outflow failure. Recent meta-analyses have shown no advantages of one technique over the others, except for the laparoscopic method [18][19][20]. Therefore, the International Society for Peritoneal Dialysis recommends that the choice of PDC insertion method should be based on patient factors, facility resources, and operator expertise [21].

The present study has a few limitations. Being a retrospective and single-center study, the generalizability of our findings may be limited. Limitations related to the retrospective design of the study include potential biases in patient selection and data collection and the absence of a control group further limits the robustness of our conclusions. Future prospective, multicenter studies are needed to validate our findings and explore additional factors influencing PD catheter survival.

In conclusion, non-infectious complications were the only independent factor significantly associated with PDC survival. Despite the significant number of infectious complications, including peritonitis, these did not result in a substantial decrease in catheter survival in the multivariate analysis. These findings emphasize the importance of effectively managing non-infectious complications to ensure successful and long-term use of PDCs. Preventive measures, such as omentectomy simultaneously with PDC implantation, may be considered on a case-by-case basis.