Discussion
In the cohort of 172 adults undergoing first-time peritoneal dialysis catheter placement at Oslo University Hospital, Ullevål, cumulative catheter survival, peritonitis incidence, hollow-organ injury, and bleeding were largely consistent with international quality indicators (10) . However, the rate of exit-site infection was somewhat higher than the recommended indicator.
Within 30 days, 11 % of patients developed an exit-site infection, which exceeded the suggested threshold of 5 % (10) . Although diagnostic criteria are clearly defined for exit-site infection, variability between treatment centres is inevitable, as assessments of erythema and secretion are subjective. Many more patients than those with a relevant exit-site infection are likely to have a positive bacterial culture from the site. Some patients may therefore receive a diagnosis based on colonisation and moderate clinical findings, while others may not be diagnosed even in the presence of infection. Other Norwegian studies indicate that exit-site infections are relatively common, particularly at later time points, with an incidence of approximately 20 % (11, 12) .
Several measures are recommended to prevent early exit-site infection, the most important of which are maintaining a sterile surgical area postoperatively, avoiding premature dressing changes and keeping the exit-site incision as small as possible (10) . Some treatment centres, including in Norway, subcutaneously 'bury' the catheter until it is needed in order to prevent bacterial exposure. Routine preoperative antibiotic prophylaxis to protect against Staphylococcus aureus is also recommended (10) .
At Oslo University Hospital, Ullevål, 1 gram of cefazolin is administered intravenously perioperatively in patients with implanted catheters. In this study, no data were available on the type and timing of antibiotic prophylaxis received. Such information could have helped explain the somewhat high incidence of exit-site infections. Regardless of cause, the incidence of exit-site infections was higher than desirable, and efforts are underway to reduce it. Once the catheter cuff is embedded in subcutaneous tissue, the risk of progression to peritonitis decreases. Nevertheless, about 20 % of patients with exit-site infections develop peritonitis (13) ; a finding confirmed in this study, where a clear correlation was observed between exit-site infection and peritonitis.
At Oslo University Hospital, Ullevål, one-year cumulative catheter survival was 81 %. Crabtree et al. indicate a minimum survival of 80 % for open placement and 95 % for advanced laparoscopic placement (10) . Advanced laparoscopic techniques allow visualisation of correct catheter positioning, lysis of adhesions and fixation of the omentum or sigmoid colon if needed, likely reducing the risk of catheter failure (10) . Studies comparing different catheter placement methods (laparoscopic, percutaneous and open) report one-year survival of 80–90 % (14–18) . Our results align with international studies, but increased use of laparoscopic placement may further improve one-year catheter viability. However, placement of peritoneal dialysis catheter under local anaesthesia is less burdensome for seriously ill patients than laparoscopic surgery under general anaesthesia and requires fewer anaesthesia resources.
Poor drainage from a peritoneal dialysis catheter may result from migration out of the pelvis, which can be confirmed by abdominal X-ray. In cases of catheter tip migration from the pelvis, radiological or laparoscopic repositioning can be attempted (19) . Image-guided repositioning is often time-consuming and painful, and had a low success rate in our study. Laparoscopy requires general anaesthesia, but had a higher success rate in this study. It also allows fixation of the catheter toward the pelvis and the diagnosis and resolution of other issues affecting function. We therefore recommend considering laparoscopic repositioning as the first-line approach in cases of poor catheter function due to displacement.
In this cohort, two perioperative bladder injuries occurred, and one patient required perioperative blood transfusions. The recommended threshold for these complications, as proposed by Crabtree et al., is 1 %, which our findings were close to (10) .
A total of 16 surgeons were responsible for the procedures in this study, with some only performing a few. Although the operation itself is technically straightforward, several critical steps influence both short and long-term outcomes (20) . The number of procedures required to master an abdominal procedure and reach the learning plateau has been estimated at approximately 20–40 (21) . At Ullevål Hospital, the annual volume of catheter insertions was around 30. To maintain case volume and quality, we streamlined the surgical workflow and limited procedures to a smaller team of surgeons.
A limitation of this study is its retrospective design, which relied on existing medical records, leading to incomplete information when key details were inadequately documented. To reduce confirmation bias, we used a predefined variable list for collecting data and performed random checks to verify ambiguous entries. Nevertheless, these factors may have affected the study's reliability and validity and should be considered when interpreting the results.
Strengths of the study include near-complete inclusion of all patients receiving a peritoneal dialysis catheter at one of Norway's largest treatment centres over a six-year period. The study also presents data from Norway, which is underrepresented in the literature (11, 12) .
Conclusion
Conclusion
Peritoneal dialysis catheters inserted at Oslo University Hospital, Ullevål, in the period 1 January 2017–31 December 2022 generally functioned satisfactorily, and the incidence of complications was largely comparable to international quality indicators. However, the exit-site infection rate was somewhat higher than desirable. Continuous efforts are underway to improve this outcome and the safety of procedures.