The impact of the superficial cuff position on the exit site and tunnel infections in CAPD patients

Exit-site relocation by external splicing: A rescue therapy for damaged tunneled central venous catheter

Effective hemodialysis (HD) depends on efficient, durable, and safe vascular access. Despite incessant efforts to reduce the use of tunneled central venous catheter (tCVC), late referrals, poor planning, improper creation of arteriovenous fistula, and lack of appropriate blood vessels are responsible for high prevalence of tCVC in the dialysis population. Specific mechanical problems, such as cracked hubs, broken clamps, leaky connectors, and bloodline rupture, can jeopardize the tCVC integrity. In case of tCVC damage at the distal part of the extracutaneous portion, most catheters are usually fixed using specific repair kits. However, when the bloodline is cracked close to the exit-site, the catheter exchange over a guide wire or the placement at a new site are considered the only viable options. However, the preservation of patient vascular assets should be prioritized, especially in patients with limited or exhausted access possibilities. Thus, in order to rescue the catheter and preserve the patient's vascular asset, we describe an innovative technique to fix tCVC bloodline perforations located in the proximity of the exit-site. The procedure consists in creating a new exit-site through the shortening of the tunnel tract. The intervention of exit-site relocation by external splicing represents an attractive option to treat unfixable tCVC damage or tunnel erosion without the need for catheter removal or exchange. This mini-invasive procedure is rapid, safe, and optimally tolerated by the patient. However, the prerequisites for this procedure are an exit site-cuff distance of at least 5 cm and the availability of an adequate repair kit. Exposition of the device along the subcutaneous tract due to chronic erosion of the tunnel can be simultaneously resolved by this intervention.

Tunnel ultrasound can guide the use of peritoneal dialysis catheter exit site relocation by external splicing and cuff removal in refractory tunnel infection

BACKGROUND

Peritoneal dialysis (PD) catheter related infections continue to be a major cause of morbidity and transfer to hemodialysis (HD) in PD patients. The treatment of tunnel infection (TI) could be challenging, especially when the infection involves the superficial cuff requiring the removal of the catheter. To spare the patient the loss of the catheter and the transfer to HD, several mini-invasive surgical techniques have been proposed as rescue therapy. Furthermore, nowadays, the rapid growth of digital technology has enormously increased the diagnostic sensibility of the echo signal allowing to accurately defines the extent of the infectious process along the PD catheter tunnel.

METHODS

Between 1st January 2020 and 31st December 2021 seven patients who underwent exit-site relocation by external splicing and cuff removal at our institution due to refractory TI were included in the study. All patients were followed until 12 months after the procedure. As soon as TI was defined refractory to the medical therapy, an ultrasonographic examination of the catheter tunnel was performed to define the extent of the infectious episode.

RESULTS

Among the 7 infectious episodes, 4 were caused by P. aeruginosa, and 3 by S. aureus. Around the superficial cuff the hypo/anechoic collections detected by ultrasounds showed a mean diameter of 3.05 ± 0.79 mm. The exit-site relocation by external splicing and cuff removal was successful in all cases (7/7, 100%).

CONCLUSIONS

In our experience the use of exit site relocation by external splicing and cuff removal as rescue therapy for TI with positive ultrasounds for TI limited to superficial cuff involvement and without secondary peritonitis, yielded to promising results with a success rate of 100%. This preliminary experience underlines the paramount usefulness of tunnel echography in accurately defining the extent of TI and, consequently, guiding the choice of the therapeutical approach in refractory TI.

Peritoneal dialysis related peritonitis: insights from a long-term analysis of an Italian center

BACKGROUND

Peritonitis is a common and severe complication of peritoneal dialysis (PD). For comparative analysis standardized definitions as well as measurements and outcomes are crucial. However, most PD-related peritonitis studies have been using heterogenous definitions and variable methods to measure outcomes. The ISPD 2022 guidelines have revised and clarified numerous definitions and proposed new peritonitis categories and outcomes.

METHODS

Between 1st January 2009 and 31st May 2023, 267 patients who started PD at our institution were included in the study. All PD-related peritonitis episodes that occurred in our unit during the study period were collected. The new definitions and outcomes of ISPD 2022 recommendations were employed.

RESULTS

The overall peritonitis rate was 0.25 episode/patient year. Patient cumulative probability of remaining peritonitis-free at one year was 84.2%. The medical cure and refractory peritonitis rates were equal to 70.3 and 22.4%, respectively. Culture-negative peritonitis accounted for 25.6% of all specimens. The rates of peritonitis associated death, hemodialysis transfer, catheter removal and hospitalization were 6.8%, 18.3%, 18.7% and 64.4%, respectively. Relapsing, repeat, recurrent and enteric peritonitis accounted for 7.8%, 6.8%, 4.1% and 2.7% of all episodes, respectively. Catheter insertion, catheter related and pre-PD peritonitis were 4.2, 2.1 and 0.5%.

CONCLUSIONS

The implementation of PD-related peritonitis reports using standardized definitions and outcome measurements is of paramount importance to enhance clinical practice and to allow comparative studies.

Relationship between number of daily exchanges at CAPD start with clinical outcomes

BACKGROUND

Peritoneal dialysis (PD) continues to be demanding for patients affected by kidney failure. In kidney failure patients with residual kidney function, the employment of incremental PD, a less onerous dialytic prescription, could translate into a decrease burden on both health systems and patients.

METHODS

Between 1st January 2009 and 31st December 2021, 182 patients who started continuous ambulatory peritoneal dialysis (CAPD) at our institution were included in the study. The CAPD population was divided into three groups according to the initial number of daily CAPD exchanges prescribed: one or two (50 patients, CAPD-1/2 group), three (97 patients, CAPD-3 group) and four (35 patients, CAPD-4 group), respectively.

RESULTS

Multivariate analysis showed a difference in term of peritonitis free survival in CAPD-1/2 in comparison to CAPD-3 (hazard ratio (HR): 2.20, p = 0.014) and CAPD-4 (HR: 2.98, p < 0.01). A tendency towards a lower hospitalisation rate (CAPD-3 and CAPD-4 vs. CAPD-1/2, p = 0.11 and 0.13, respectively) and decreased mortality (CAPD-3 and CAPD-4 vs. CAPD-1/2, p = 0.13 and 0.22, respectively) in patients who started PD with less than three daily exchanges was detected. No discrepancy of the difference of the mean values between baseline and 24 months residual kidney function was observed among the three groups (p = 0.33).

CONCLUSIONS

One- or two-exchange CAPD start was associated with a lower risk of peritonitis in comparison to three- or four-exchange start. Furthermore, an initial PD prescription with less than three exchanges may be associated with an advantage in term of hospitalisation rate and patient survival.

Utility of ultrasonographic examination in catheter-related infections in peritoneal dialysis: a clinical approach

Peritoneal dialysis- (PD) related infections continue to be a major cause of morbidity and mortality in patients on renal replacement therapy via PD. However, despite the great efforts in the prevention of PD-related infectious episodes, approximately one third of technical failures are still caused by peritonitis. Recent studies support the theory that ascribes to exit-site and tunnel infections a direct role in causing peritonitis. Hence, prompt exit site infection/tunnel infection diagnosis would allow the timely start of the most appropriate treatment, thereby decreasing the potential complications and enhancing technique survival. Ultrasound examination is a simple, rapid, non-invasive and widely available procedure for tunnel evaluation in PD catheter-related infections. In case of an exit site infection, ultrasound examination has greater sensitivity in diagnosing simultaneous tunnel infection compared to the physical exam alone. This allows distinguishing the exit site infection, which will likely respond to antibiotic therapy, from infections that are likely to be refractory to medical therapy. In case of a tunnel infection, the ultrasound allows localizing the catheter portion involved in the infectious process, thus providing significant prognostic information. In addition, ultrasound performed after two weeks of antibiotic administration allows monitoring patient response to therapy. However, there is no evidence of the usefulness of ultrasound examination as a screening tool for the early diagnosis of tunnel infections in asymptomatic PD patients.

The use of mini-invasive surgical techniques to treat refractory exit-site and tunnel infections in peritoneal dialysis patients: a clinical approach

Peritoneal dialysis-(PD) related infections continue to be a major cause of morbidity and mortality in patients on PD. Although great advances have been made in the prevention and treatment of infectious complications over the past two decades, catheter-related infections represent a significant cause of technical failure in PD. Recent studies support the role of exit-site/tunnel infections in causing peritonitis. Peritonitis secondary to tunnel infection led to catheter loss in most cases. Thus, removing the catheter when exit-site/tunnel infection is refractory to medical therapy has been recommended. This approach requires interrupting PD and, after the placement of a central venous catheter, and transferring the patient to haemodialysis. In order to continue PD, simultaneous catheter removal and replacement of the PD catheter has been suggested. Although simultaneous catheter removal and replacement avoids temporary haemodialysis, it implies the removal/reinsertion of the catheter and the immediate initiation of PD with the risk of mechanical complications, such as leakage and malfunction. Hence, several mini-invasive surgical techniques, such as curettage, cuff-shaving, removal of the superficial cuff, and partial reimplantation of the catheter, have been proposed as rescue treatments. These procedures may allow the rescue of the catheter with a success rate of 70-100%. Therefore, in case of refractory exit-site/tunnel infection, a mini-invasive surgical revision should be considered before removing the catheter.

Incremental peritoneal dialysis allows to reduce the time spent for dialysis, glucose exposure, economic cost, plastic waste and water consumption

BACKGROUND

Incremental peritoneal dialysis (incPD) as the initial PD strategy represents a convenient and resource-sparing approach, but its impact on patient, healthcare and environment has not been thoroughly evaluated.

METHODS

This study includes 147 patients who started incPD at our institution between 1st January, 2009 and 31st December, 2021. Adequacy measures, peritoneal permeability parameters, peritonitis episodes, hospitalizations and increase in CAPD dose prescriptions were recorded. The savings related to cost, patient glucose exposure, time needed to perform dialysis, plastic waste, and water usage were compared to full-dose PD treatment.

RESULTS

During the study follow-up 11.9% of the patients transitioned from incremental to full dose PD. Patient cumulative probability of remaining on PD at 12, 24, 36, 48 and 60 months was 87.6, 65.4, 46.1, 30.1 and 17.5%, respectively. The median transition time from 1 to 2 exchanges, from 2 to 3 and 3 to 4 exchanges were 5, 9 and 11.8 months, respectively. Compared to full dose PD, 1, 2, and 3 exchanges per day led to reduction in glucose exposure of 20.4, 14.8 or 8.3 kg/patient-year, free lifetime gain of 18.1, 13.1 or 7.4 day/patient-year, a decrease in cost of 8700, 6300 or 3540 €/patient-year, a reduction in plastic waste of 139.2, 100.8 or 56.6 kg/patient-year, and a decline in water use of 25,056, 18,144 or 10,196 L/patient-year.

CONCLUSIONS

In comparison with full-dose PD, incPD allows to reduce the time spent for managing dialysis, glucose exposure, economic cost, plastic waste, and water consumption.

Simultaneous replacement and removal of the peritoneal catheter is effective in patients with refractory tunnel infections sustained by S. aureus

BACKGROUND

In tunnel infection (TI) refractory to medical therapy or in case of TI that occurs simultaneously with peritonitis, the removal of the peritoneal catheter has been proposed. This approach requires the interruption of peritoneal dialysis (PD) and the creation of a temporary vascular access. However, simultaneous removal and reinsertion of the PD catheter (SCR) represents another possible therapeutic approach.

METHODS

We analysed the outcome of 20 patients (10 men and 10 women, mean age 65.5 ± 16.3 years) treated by CAPD for a mean period of 24.3 ± 14.2 months who underwent to SCR for the treatment of TI unresponsive to medical therapy or TI that occurred simultaneously with peritonitis at Fondazione Ca' Granda Ospedale Maggiore Policlinico. All the patients restarted CAPD exchanges within 24 h from catheter placement.

RESULTS

SCR was successful in 80% (16/20) of the cases. In particular, SCR was effective in 100% (11/11) of the TI with or without associated peritonitis sustained by S. aureus. However, SCR failed in 57% (4/7) of TI associated with relapsing peritonitis and in one patient with TI secondary to Enterobacter. No early mechanical complications (within 3 months after SCR) occurred when CAPD was restarted.

CONCLUSIONS

SCR of the PD catheter through double-purse string technique represents an effective treatment for TI without or with simultaneously peritonitis sustained by S. aureus avoiding the patient the need for temporary hemodialysis and second surgical procedure. However, SCR could be contraindicated in case of relapsing peritonitis.

Analysis of mechanical complications in urgent-start peritoneal dialysis

BACKGROUND

Peritoneal dialysis (PD) is an excellent, but underutilized dialysis technique. Thus, its implementation may depend also on the chance to offer this modality of treatment to patients referred late to the nephologists. This approach has recently been named "urgent-start peritoneal dialysis" (UPD). The main barrier to this practice is represented by the fear of early mechanical complications.

METHODS

All prevalent patients needing urgent-start PD at our institution between 1 January, 2009 and 31 December, 2019 were included in the study. During this period, 242 peritoneal catheters were inserted in 222 patients. In all patients, an anti-leakage/dislocation suture was made. PD was started within 24 h from catheter placement.

RESULTS

The early incidence of leakages, catheter dislocations, omental wrappings, bleedings, peritonitis and exit-site infections was 11/242 (4.5%), 5/242 (2%), 3/242 (1.2%), 2/242 (0.8%), 6/242 (2.5%) and 4/242 (1.6%), respectively. No bowel perforations were observed. Nearly one third of the late complications (13/45; 35.2%) resulted in discontinuation of PD, while one fourth (11/45; 24.4%) required surgical revision. The remaining episodes (21/45; 46.6%) were successfully managed by a conservative approach. The survival of the catheter at 3, 6, 12, 24, 36 and 48 months was 93.6, 91.2, 84.8, 77.4, 65.5 and 59.3%, respectively. The technique survival at 3, 6, 12, 24, 36 and 48 months was 97.2, 94.9, 87.6, 78.9, 66.6 and 60.0%, respectively. The main causes of PD drop-out included infectious complications (36.8%) followed by mechanical complications (17.5%).

CONCLUSIONS

A tight seal between deep cuff and surrounding tissues (double purse-string technique) in association with a starting low-volume exchange scheme allows to minimize early and late mechanical complication in UPD.