Stepwise Initiation of Peritoneal Dialysis Using the Moncrief and Popovich Technique (SMAP): Evaluation of Early Complications and Optimal Embedding Duration

Background: In Japan, a two-step approach to peritoneal dialysis (PD) catheter insertion known as the Moncreiff and Popovich method (SMAP) is widely adopted. This method is expected to reduce complications compared to the conventional one-step method; however, long-term embedding carries the risk of catheter occlusion. In this study, we evaluated early complications associated with SMAP and focused on determining the optimal embedding periods. Methods: Single-center retrospective observational study conducted at Kokura Memorial Hospital. A total of 217 patients (243 catheters) who underwent PD catheter placement via laparotomy between April 2021 and May 2024 were included. Early complications—defined as events occurring within one month of PD initiation—were evaluated. After propensity score matching, outcomes were compared between the SMAP and non-SMAP groups. Complications were categorized as emergency hemodialysis (HD), surgical intervention for catheter obstruction, dialysate leakage, or infection (peritonitis or catheter-related). In the SMAP group, complication rates were further stratified by embedding periods. Results: The median age was 70 years; 160 patients (73.7%) were male, and the median BMI was 23.3 kg/m2. Previous abdominal surgery was documented in 57 cases (26.2%), and 126 patients (58.0%) had diabetes. SMAP was performed in 89 cases (36.6%). The SMAP group had a lower prevalence of diabetes and tended to have higher baseline serum albumin and estimated glomerular filtration rate (eGFR). Although there was a trend toward fewer emergency HD sessions and dialysate leaks in the SMAP group, these differences were not statistically significant after matching. Among SMAP patients, those with embedding periods ≥180 days had a significantly higher rate of surgical intervention due to catheter obstruction (p = 0.001). Conclusion: Dialysate leakage improved within two weeks postoperatively and was not observed in the SMAP group. In this study, the risk of catheter occlusion requiring surgical intervention significantly increased when the embedding period was 180 days or longer. These results suggest that SMAP is an effective treatment, but an embedding period of less than 180 days is preferable, and clinicians should consider additional interventions when the embedding period exceeds 180 days.