Abdominal Surgery History and Peritoneal Dialysis Catheter Failure: Can We Really Know Who’s at Risk?

Dr. Michael Granda is an Acting Assistant Professor in the Division of Nephrology at the University of Washington. He completed his internal medicine residency at the University of Miami in 2019, and continued his path in nephrology to the University of Washington where he completed his clinical nephrology fellowship in 2021 and has remained ever since. Dr. Granda’s research focuses include proximal tubule secretory clearance and the use of imaging to investigate kidney physiology. When he’s not pontificating about salt water at work, you can find Dr. Granda at the lake or in the kitchen.

Selecting a dialysis modality is both a science and an art, and requires assessing a number of patient factors, preferences, and criteria. On first glance, eligibility for peritoneal dialysis (PD) catheter placement would seem to be a more objective determination but is surprisingly limited in evidence. Many nephrologists believe that prior abdominal surgery is at least a relative contraindication for PD. Indeed, post-operative adhesions are common, have been associated with reduced PD efficacy, and with extensive adhesions are considered an absolute contraindication. Prior abdominal surgery is also suggested to contribute to dialysate leakage by compromising the integrity of the abdominal or pleural wall.

There are limited data associating prior abdominal surgery and the risk for PD catheter dysfunction or failure. However, these studies suffered from small sample sizes or single-center designs. In the United States, only 10% of PD catheters are placed using an open surgical technique due to the higher risk for complications, limiting the applicability of some prior data.

Table 1. Studies reporting PD catheter complication rates between patients with and without prior abdominal surgeries AS = abdominal surgery. * p < 0.05 © Granda.

Enter Wazaira Khan et al, who using the International Society of Peritoneal Dialysis (ISPD) North American PD Catheter Registry, examined the risk of prior abdominal surgery with:

• PD catheter abandonment (removal before use)
• Interruption of PD, or
• Termination of PD due to catheter-related complications.

These data spanned from 2011-2020 from 11 institutions in both Canada and the United States in 855 adult patients receiving their index PD catheter placement (259 with prior abdominal surgery and 596 without prior abdominal surgery, median follow-up for outcomes 12 months).

No association was seen between any prior abdominal surgery and the primary PD catheter outcomes (adjusted HR 1.12, 95% CI 0.68-1.84), nor was there a dose-dependent association with the number of abdominal surgeries. When stratified by surgical location, only a history of upper abdominal procedures had a higher risk (aHR 1.62, 95% CI 1.04-2.53). An open procedure was associated with a greater risk of the primary outcome although relatively few (4.5%) patients received it.

The authors conclude, “A history of prior abdominal procedure(s) should not influence the decision to attempt PD catheter insertion in most cases”. But herein lies the rub: it already did influence the decision to attempt PD catheter insertion. Only patients deemed eligible for PD by a nephrologist could be included in this study, potentially limiting the patients most at risk for catheter failure. Furthermore, data from this registry represents patients of healthcare centers presumed to have a specialized focus on PD which may further introduce bias by 1) exposure to nephrologists with specific training in PD and presumably more experienced in patient selection, and 2) insertions performed by surgeons with a greater volume of these procedures. These limitations are readily acknowledged by the authors in this well-done study and calls to the forefront some important questions.

So, can we really know who’s at risk for PD catheter failure with respect to prior abdominal surgery? What does this study add if there is no difference in outcomes? To conclude that prior abdominal surgery “should not influence the decision to attempt … insertion” would suggest this factor is irrelevant. In my opinion, this study demonstrates that nephrologists (at least those with a specific focus on PD) have a good gestalt for limiting referrals of patients with higher-risk histories of prior abdominal surgeries. The fact that upper but not lower abdominal surgeries were associated with a greater risk for catheter failure may speak to this internal selection process, and further demonstrate a blind spot in assigning risk based on anatomic location.

Or — perhaps there truly is no difference, or that nephrologists are excessively cautious in who they refer with prior abdominal surgery. No reasonable study design can directly answer this question unless we are to randomize impending PD patients to abdominal surgery, nor can we ignore the implicit selection bias in a retrospective study. This study by Khan et al, however, is likely the closest we can get to the truth, and it would seem that prior abdominal surgery should continue to influence our decision to refer for PD catheter placement, with more careful consideration for those with prior upper abdominal surgeries.

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• Source: https://ajkdblog.org/2024/09/18/abdominal-surgery-history-and-peritoneal-dialysis-catheter-failure-can-we-really-know-whos-at-risk/