What is acute Peritoneal Dialysis?
Many patients need urgent or emergent dialysis. This occurs in patients who are not previously known to have chronic kidney disease (CKD) or when dialysis is started in situations of progressively deteriorating, but known, CKD without a permanent access (i.e., a fistula or a PD catheter). Urgent or emergent dialysis also occurs in situations of acute kidney injury (AKI). In the United States, Canada, and Europe, these patients are usually started on HD after placement of a CVC. However, there is movement to increase use of PD in these situations, with the goal of avoiding CVCs (tunneled and untunneled) and the morbidity and mortality associated with them.
PD can be used in many patients who have an unplanned start for dialysis. In a retrospective analysis comparing the outcomes of a group of patients started acutely on PD and a nonmatched group of patients with a planned start on chronic PD, there was no difference in infectious complications or technique survival rate, although mechanical complications were significantly more common in the acute group. In another small study in France, patients were nonrandomly selected for unplanned start with either PD or HD. Median time from PD catheter insertion to PD start was 4 days. The 1-year survival adjusted for comorbidity (79% survival on HD compared with 83% on PD) and the rehospitalization rate were similar. In a more recent observational cohort study from Germany, groups started on either unplanned acute PD or HD had equivalent mortality rates. HD patients had a significantly higher risk of bacteremia, presumably due to CVC use. PD was initiated within 12 hours after PD catheter implantation in this study, delivered nocturnally thrice weekly. Urgent start PD has also been proven effective in the elderly population. It should be noted that these are all single-center studies where the norm is HD. One would anticipate that increasing experience using PD for unplanned starts would improve outcomes.
Published experience with PD for AKI is limited. Ponce et al. demonstrated that high-volume PD (weekly Kt/V ~ 3.5) could achieve adequate metabolic and fluid control in AKI patients without severe fluid overload or hypercatabolism. A prospective randomized experience of 120 patients comparing high-volume PD to six times per week HD showed both similar survival (58% and 53%) and recovery of kidney function (28% and 26%). Although results here are encouraging, experience with acute placement of PD catheters and PD therapy itself is a critical factor for success. Acute abdominal processes would be a contraindication to using acute PD.