title: Prolonged duration of peritoneal dialysis catheter embedment does not lower the catheter success rate.
abstract: OBJECTIVE
  Since 2000, we have used the Moncrief-Popovich technique as our standard method for peritoneal dialysis (PD) catheter insertion. The subcutaneous portion of the catheter is externalized immediately before initiation of PD. We undertook the present review to investigate whether duration of catheter embedment affects catheter or patient outcome.
  
  
  METHODS
  All catheters inserted beginning 1 January 2000 and externalized by 31 December 2008 were included. The primary outcome was catheter survival. Secondary outcomes were catheter patency (no fibrin plug or omental wrap) and complications within 90 days after externalization. A standard peritoneal equilibration test was used to classify peritoneal membrane transport status. Proportional hazards regression models were used to test whether duration of embedment affected catheter outcomes. The models treated embedment duration as both a continuous predictor and a categorical predictor categorized by tertile.
  
  
  RESULTS
  A total of 134 catheters were implanted and externalized. Twelve patients received 2 catheters each. To ensure statistical independence of the observations, 12 of the latter 24 catheters were excluded (1 chosen randomly from each patient), resulting in a useable sample size of 122 catheters. The total duration of observation was 2359 patient-months. The median duration of catheter embedment was 40.5 days (range: 2 - 788 days). After controlling for sex, race, age, and diabetes status, embedment duration did not have a significant effect on catheter survival as a continuous predictor or as a categorical predictor. Additionally, the 95% confidence interval for the 30-day effect of embedment duration ruled out a change of more than 20.6% in the hazard of catheter malfunction or infection. Of the studied catheters, 89.3% were patent and functioned properly immediately upon externalization. The remaining 13 catheters (10.7%) lacked patency on externalization because of fibrin plug or kinking (n = 10) or omental wrap (n = 3); however, 12 of the 13 non-patent catheters were corrected laparoscopically, and the patients resumed PD. Only 1 patient transferred to hemodialysis. Overall, 121 of 122 buried catheters (99.2%) were used for PD. Other complications within 90 days of catheter externalization included incision site and tunnel infection in 2 cases (1.6%), exit-site leak in 2 cases (1.6%), and coagulase-negative staphylococcal peritonitis in 1 case (0.8%).
  
  
  CONCLUSIONS
  Duration of catheter embedment before externalization did not affect catheter survival and did not influence subsequent peritoneal membrane transport status. The overall effect of increasing embedment duration by 30 days is, at most, a 20.6% increase or decrease in the hazard of catheter failure, but the actual hazard may be much smaller or nonexistent. Larger studies are needed to further explore the ideal duration of embedment.
authors.affiliation: Division of Renal Diseases and Hypertension, University of Colorado-Denver, Aurora, Colorado 80045, USA.
authors.forename: Elwaleed
authors.initials: E
authors.lastname: Elhassan
authors.forename: Bryan
authors.initials: B
authors.lastname: McNair
authors.forename: Maggie
authors.initials: M
authors.lastname: Quinn
authors.forename: Isaac
authors.initials: I
authors.lastname: Teitelbaum
mesh_terms: D002408:Catheters, Indwelling; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis / Q000379:methods*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome