Peritoneal dialysis (Guidelines)

Pericatheter leak: Occurs most frequently in the immediate postoperative period. Postoperative catheter leakage can largely be prevented by a break-in period of about 2 weeks, during which the wound can heal, and ingrowth of fibrous tissue can anchor the Dacron cuff(s).

Subcutaneous leak: Dialysate leaks may also occur as a late complication of CAPD. The treatment is similar to the treatment in early leakage. Late leakage is usually provoked by a sudden increase in intra-abdominal pressure, for example during coughing or heavy lifting. PD fluid can dissect through peritoneal discontinuities into the soft tissues of the anterior abdominal wall. This can occur along the catheter insertion site or through defects in the peritoneum. The extra peritoneal dialysate can cause odema in the abdominal wall and the genitals. The diagnosis of fluid dissection can be facilitated by nuclear medicine and radiological imaging.

Catheter obstruction: Mechanical obstruction due to clamps or kinking should be excluded. Total catheter obstruction occurs when fibrin, cellular debris or blood clots are present in the catheter. Forcing 20 to 50 mL of dialysate or sodium chloride 0.9% with a syringe into the catheter lumen can relieve the obstruction. Sometimes intraluminal heparin is useful and finally, fibrinolytic agents such as urokinase can be used to dissolve the clot. Other causes include catheter malposition due to constipation which may be confirmed by x-ray. Occasionally, this may improve when the patient has a bowel movement, but surgical intervention may be required to reposition the catheter.

Catheter malposition: Following exclusion of the causes of catheter obstruction above a catheter may be malfunctioning due to the presence of abdominal adhesions causing the omentum to attach to the catheter tip or the tip to migrate out of the pelvic cavity. This will require surgical intervention, and it may be necessary to replace the catheter.

Hernia: The increased intra-abdominal pressure during CAPD can provoke hernia formation. The most common hernias are umbilical, inguinal and incisional hernias. Predisposing factors for the development of hernias are a weak anterior abdominal wall, congenital defects of the abdominal wall and polycystic disease. Small hernias have a risk for bowel incarceration. Large hernias do not carry as great a risk but may be troublesome for the patient. Hernias should be repaired surgically. Usually, after a period of haemodialysis, CAPD can be restarted 2 to 4 weeks after the operation.

Abdominal discomfort on infusion: May be due to the rate of inflow, the temperature or pH of the dialysate and usually subsides when the infusion is complete. This symptom may be reduced by ensuring dialysate is warmed to the correct temperature and reducing the rate of inflow.

Abdominal discomfort on drain: May be experienced when the last of the fluid is drained from the peritoneum and is usually resolved by leaving a small amount of fluid (approximately 200mL) in the peritoneum or filling with PD fluid.

Shoulder pain: Postoperative shoulder pain, which is interpreted as reference pain from the diaphragm, is present in about 25% of patients and disappears spontaneously within a few days. After the start of CAPD patients may complain of abdominal pain, usually localized in the pouch of Douglas. The pain is most prominent with empty abdomen or during rapid inflow of the dialysate and can be decreased by diminishing the inflow rate. Usually, this pain lessens or disappears within a few months after the start of CAPD.

Blood-stained effluent: Usually occurs in menstruating females. This usually requires no intervention and resolves in a few days. Following catheter insertion minor intra-abdominal bleeding may occur, which will stop after the first dialysate exchanges. Laceration of medium-sized or large blood vessels in the anterior abdominal wall, resulting in intensifying bleeding in the dialysate, requires surgical intervention.

Hydrothorax: Secondary to leakage of peritoneal dialysate occurs in 1.6 to 10% of CAPD patients and is caused by anatomical defects of the diaphragm in the presence of increased intra-abdominal pressure. Suspending PD for a period of 2 to 8 weeks may be sufficient to allow healing of the pleuroperitoneal communication and prevent the accumulation of fluid in the pleural space. When these measures are not successful, surgical closure of the diaphragmatic defects can be considered in patients strongly motivated to continue CAPD, but in practice patients with a hydrothorax will discontinue with peritoneal dialysis.

Accidental disconnection of the catheter or adapter. It is possible for the disinfection cap to become disconnected from the extension set or the extension set can become disconnected from the titanium adapter. The renal staff must be contacted immediately, and the contamination protocol must be implemented.

Crack or fracture in the catheter or adapter: The contamination protocol must be implemented. The catheter must be trimmed and the titanium and extension set changed.

Peritonitis

Peritoneal dialysis-associated peritonitis is a serious complication of PD. It is the most common type of PD-related infection resulting in increased healthcare utilisation and is associated with significant harms including pain, treatment cost, transfer to haemodialysis and death, as well as alterations of the peritoneal membrane and peritoneal adhesions which can make long-term treatment with PD challenging. The International Society of Peritoneal Dialysis (ISPD) provide detailed, evidence-based guidelines to guide practice and improve patient outcomes. The ISPD suggested standard of less than 0.4 episodes per patient year on PD.

PD-associated peritonitis can be diagnosed when at least two of the following are present:

1. Clinical features consistent with peritonitis (abdominal pain, cloudy dialysis effluent);
2. Dialysis white cell count >100/microlitre with >50% polymorphonuclear leucocytes;
3. Presence of organisms on Gram stain or culture of dialysis effluent.

Clinical features include

• Abdominal pain (occurs in 80% of patients)
• Cloudy effluent
• Nausea (30%) and Diarrhoea (7 to 10%)
• Fever (50%)
• Loss of ultrafiltration
• Poor drainage

There are 5 main routes of infection causing peritonitis

• Intraluminal: Contamination of dialysate by bacteria during bag exchange is probably the most common cause of peritonitis. This is supported by the observation that the incidence of peritonitis decreases when PD is done for longer period of time, reflecting increasing patient experience.
• Periluminal: Penetration of bacteria is very likely when peritonitis episodes are preceded by an exit-site infection or tunnel infection.
• Transmural: Penetration of bacteria through the intestinal wall is possible and this may be the route of contamination in peritonitis episodes caused by Gram negative bacteria (Enterobacteraceae).
• Haematogenous: Transferred via the bloodstream
• Vaginal: Ascending through the vagina

Definition of peritonitis episodes:

• Relapsing peritonitis: Defined as a further episode of peritonitis caused by the same organism (or culture negative) occurring within 4 weeks of completing antibiotic therapy for peritonitis.
• Recurrent peritonitis: A further episode of peritonitis caused by a different organism, occurring within 4 weeks of completing antibiotics for peritonitis.
• Repeat peritonitis: Defined as a further episode of peritonitis more than 4 weeks after completing antibiotics, with the same organism.

Outcome of peritonitis

Following an episode of peritoneal dialysis related peritonitis is classified as:

• Medical Cure: Complete resolution of peritonitis together with NONE of the following complications: relapse, recurrent peritonitis, catheter removal, transfer to haemodialysis for ≥30 days or death.
• Refractory: Peritonitis episode with persistently cloudy bags or persistent dialysis fluid count >100 / µlitre (or mm³) after 5 days appropriate antibiotic therapy resulting in catheter removal
• Patient death: This includes patients who die within 30 days of presentation of peritonitis even if the effluent WCC had cleared.

Prevention of peritonitis

• Methicillin sensitive Staph aureus (MSSA) screening / eradication
• Use of exit site antibiotic cream
• Antibiotics at catheter insertion
• Antibiotics for invasive procedures
• Antibiotics for contamination episodes

Exit site / tunnel infection:

Unlike peritonitis, exit site infections have no singular precise definition. Definitions may vary from unspecified clinical signs of infection confirmed with a positive culture to a description of marked redness around the exit site accompanied by pain, induration, drainage or granulation tissue. The presence of a causative microorganism in the culture of the exit site may facilitate the diagnosis.

An exit site is healed approximately 6 weeks post catheter implantation and is usually dry. A slight crust formation around the exit site is generally not an indication of infection. A positive culture from the exit site without any signs of inflammation does not indicate infection and should better be termed ‘colonization’.

Tunnel infections can be diagnosed by erythema, oedema and/or tenderness of the subcutaneous catheter pathway. Usually, purulent drainage is present at the exit site or can be made visible by gentle massage of the tunnel. Often infection of the deep cuff is involved in an infection of the tunnel, which is rarely cured by (repeated) courses of antibiotic treatment. In most cases with deep cuff infection catheter removal is inevitable. The majority of exit site infections are caused by S. Aureus.

Exit site infections are usually treated with oral antibiotics. During exit site infection, the frequency of exit site inspection and cleansing is suggested to be at least daily. A major goal of treatment of exit site infection is early recognition of worsening infection, including the concomitant or subsequent development of a tunnel infection. Another reason to suggest daily care is review of the need for additional therapeutic options. Granulomas over the exit may require additional exit site care because they are associated with exacerbated breakdown of the exit site.

Treatment options include silver nitrate cauterisation, topical chlorhexidine application and silver ion-based dressing. Although silver nitrate cauterisation has been most commonly used, this chemical agent can cause skin burns and pain.

Besides a perfect catheter insertion technique, the cornerstone for prevention of exit site infections is proper exit site care with immobilization of the catheter. Prophylaxis with mupirocin 2% cream to the catheter exit site during dressing change may reduce this infection risk.

Monitoring and reporting of catheter-related infections

• We suggest that the rate of catheter related-infection, including organism-specific catheter-related infection, should be reported as number of episodes per year at risk.
• We recommend that the overall exit site infection rate should be no more than 0.4 episodes per year at risk.
• We suggest the proportion of PD catheter insertion-related infection within 30 days of PD catheter insertion should be less than 5% of all catheters inserted.

A culture swab should be taken from an exit site with purulent discharge.

• After examination of the exit site, the tunnel of the catheter should be inspected and palpated.
• Tenderness over the catheter pathway and drainage from the exit site after milking the track would indicate tunnel infection which, if untreated, can progress to abscess formation or catheter-related peritonitis.
• Tunnel infection is defined as the presence of clinical inflammation (erythema, swelling, tenderness or induration) with or without ultrasonic evidence of a fluid collection anywhere along the catheter tunnel.
• Oral antibiotic therapy for exit site infection should be started immediately, and treatment should be adjusted according to clinical response and swab culture.
• Patients should be reviewed within 1 week after treatment started.

• Antibiotics must be commenced until the cultures from the exit site complete and sensitivities are known.
• Review on-going antibiotic use with exit site swab results. Unless resistant to organisms, possible antibiotic can be administered as follows:
  • Gram positive: CONTINUE flucloxacillin or doxycycline
  • Gram negative: SWITCH to oral ciprofloxacin 500 mg, twice a day (see BNF warnings and MHRA Drug Safety Alert)
• Any tunnel infection should be treated with effective antibiotics for at least 3 weeks
• Within 1 to 2 weeks following completion of antibiotics for exit site infection, the exit site must be swabbed and sent for microscopy, culture and sensitivity.

All medications must be prescribed in the patient record.

• A minimum 2 week course of antibiotics has been recommended for most catheter-related infections, except for those caused by Pseudomonas for which a 3-week course is recommended.
• The fixed 2 week antibiotic treatment duration for exit site infection can be shortened to 7 to 10 days if resolution of infection is confirmed by clinical evaluation at around 1 week.
• Within one week after initial treatment, physical examination of the exit site should be performed by either clinicians or nurses experienced in managing exit site infections.
• In the literature, refractory tunnel infection has even been defined as failure to heal within 4 weeks.
• Catheter-related infections that fail to completely resolve following the recommended antibiotic course duration can be defined as refractory catheter-related infections, thereby necessitating surgical salvage interventions or catheter removal.

Notes:

• Improvement should be seen within 2 to 3 days of appropriate therapy.
• Antibiotics should be continued until infection resolved plus a further 2 days.
• Occasionally the exit site may fail to heal and become chronically infected. This may indicate catheter removal and alternative arrangement for renal replacement therapy.

Diagnosis of peritonitis

The patient has cloudy effluent / abdominal pain / pyrexia.

• Take a history, identifying possible episodes of contamination or recent PD-related infections.
• Clinical assessment of patient with temperature, blood pressure, heart rate, and examination of abdomen; looking for evidence of exit site / tunnel infection.

Essential samples

• Sample of PD effluent to be obtained. Ensure sample is taken after a minimum of 2 hour dwell time and must be no less than 1000 mL.
• Send the whole bag to Microbiology for differential white cell count, gram stain, culture and sensitivity.
• Obtain exit site swab and nasal swab for culture and sensitivity.
• Blood sample for renal profile, CRP and FBC; blood cultures if systemically unwell. 
• Peritonitis is confirmed by WCC >100/mm³ in PD effluent, of which at least 50% are polymorphs.
• The Tenckoff catheter extension set: needs to be changed after antibiotic treatment. See: Tenckhoff Catheter Extension Set Change
• The patient may only be allowed to go home in the absence of systemic illness or sepsis. Otherwise, the patient must be seen by a doctor and admitted to hospital.

INITIAL antibiotic treatment

Antibiotic therapy must cover both gram negative and gram positive organisms.

Intra-peritoneal (IP) antibiotics should be given via PD exchanges with a minimum dwell of 6 hours.

Note: The PD catheter extension set needs to changed after antibiotic treatment. See: Tenckhoff Catheter Extension Set Change

Notes:

• To ensure adequate exposure to IP antibiotics, the APD patient should do a manual daytime exchange with the IP antibiotic administered in this exchange (minimum of 6 hours dwell).
• IP ceftazidime and IP vancomycin can be given in to the same bag and are compatible with standard glucose bags and icodextrin bags.
• The APD patients can then continue to do their overnight APD treatment. 
• Treatment can be inpatient or outpatient at the discretion of clinicians, based on the patient’s clinical condition, frailty, social factors and practicalities of providing outpatient antibiotics.

Vancomycin dosing

• First dose: 30 mg/kg (maximum 3 g) given in minimum 6-hour dwell.
• Subsequent doses: 15 mg/kg given in minimum 6-hour dwell.

Patients with residual kidney function (see most recent PD adequacy test result) will clear vancomycin more rapidly and need more frequent dosing.

Patients on APD may clear vancomycin more quickly than on CAPD.

Patients at extremes of weight may need more or less frequent dosing to maintain levels

Vancomycin monitoring

Check the vancomycin level on day 2 (48 hours) after initial dose.

Vancomycin trough target level is 15 to 20 mg/L

• The timing of subsequent vancomycin level checks (and therefore re-dosing) will be determined by how quickly the vancomycin level dropped <20 mg/L and will require clinical judgement.
• Trough levels <12 are associated with poorer outcomes, so timing of vancomycin trough testing and re-dosing should be adjusted to avoid level dropping <12.

Fungal prophylaxis

To prevent fungal peritonitis, anti-fungal prophylaxis should be co-prescribed for the duration of antibiotics given for PD associated peritonitis.

Additional non-antibiotic treatment

• For fibrin: IP heparin 500 units per litre can be given.
• If required for pain: give IP 2% lidocaine 1 mL.

Ongoing management

• Review technique and consider further training.
• Consider planning vascular access as back up if patients are experiencing multiple infective episodes.

Ongoing antibiotic therapy and monitoring

• Both, IP vancomycin and IP ceftazidime should be continued until culture results are available, and ongoing antibiotic therapy is according to organism cultured (see relevant organism flow chart).
• For those that culture an organism, >75% of cases the bacteria will be identified by day 3.

Indications for catheter removal

The decision to remove the PD catheter must be made on a case-by-case basis by the clinical team, but is recommended in the following circumstances:

• Fungal peritonitis (catheter must be removed in all cases, as soon as possible)
• Refractory peritonitis (i.e. no clinical improvement by day 5)
• Relapsing, recurrent or repeat peritonitis*
• Refractory exit site and / or tunnel infection

*At the discretion of the treating clinician but recommendation is: after 2nd episode of staphylococcus, 2nd episode pseudomonas, 3rd episode coagulase negative staphylococci (even if responding to treatment).

Timing of catheter replacement after removal for infection

Concomitant catheter removal and replacement is reasonable in the context of relapsed infection where the cause is thought to be a biofilm (typically infection episodes with the same organism, relapsing quickly after antibiotics stopped. In this situation it should be done under antibiotic cover when the infection is treated (PD WCC <100/mm³) and in the absence of simultaneous exit site or tunnel infection.

When the catheter is removed in the context of refractory peritonitis the catheter should NOT be replaced until antibiotics are complete and the infection has resolved (duration of antibiotics will be determined by the organism cultured and clinical condition of the patient). This is a clinical decision which should take into consideration the alternative dialysis options for the patient.

Management after peritonitis episode

• Review technique and consider further training.
• Consider planning vascular access as back up if patients are experiencing multiple infective episodes.

Peritonitis management summary

Management algorithm: culture negative bacteria identified in dialysis effluent

• All staff and patients must be educated to perform correct aseptic non-touch technique and good hand washing technique to ensure that the risk of catheter contamination is kept to a minimum when the catheter is being handled.
• Care MUST be taken to maintain the sterility of the sterile area of the PD catheter extension set.
• IMMEDIATE action following catheter contamination is essential if peritonitis is to be avoided.

Contamination of the PD catheter should be assumed if: 

• The exposed dark blue end of the catheter is touched, coughed or sneezed upon during connection or disconnection.
• The disinfection cap falls off leaving the sterile dark blue end of the catheter exposed.
• The extension set has become disconnected at the titanium adapter.
• The extension set or PD catheter becomes damaged i.e. cut with sharp implement.

Contamination during connection

• Do NOT continue to drain. Place a sterile cap on the catheter.
• This is a dry contamination (does NOT require antibiotic treatment), and the PD catheter extension set needs to be replaced to allow the patient to continue with dialysis.
• The patient should attend for treatment at the renal unit within opening hours.
• Out of hours, discuss with the renal consultant on call who may advise to wait until the morning for the patient to attend the renal unit for PD catheter extension set change. In this case the patient needs to be advised NOT to do dialysis until the extension set has been changed

Contamination during disconnection

• Continue to disconnect and place a sterile cap on the extension set.
• The patient should attend for treatment at the renal unit within opening hours to get the PD catheter extension set changed.
• The patient needs to be advised NOT to dialyse until the extension set is changed.
• This is a dry contamination and does NOT require antibiotic treatment.
• If the PD catheter on/off switch is not closed properly at disconnection and fluid is leaking from the PD catheter, this is a wet contamination and WILL need antibiotic treatment.
• If the PD catheter extension set should become disconnected during APD treatment overnight, this is a wet contamination and needs antibiotic treatment.
• Treating the patient urgently with antibiotics will prevent peritonitis.

Contamination due to damage or cutting of the catheter

• IMMEDIATELY clamp the catheter and place a sterile swab over the puncture.
• The patient SHOULD attend for antibiotic treatment and titanium change and PD catheter extension set change at the renal unit within opening hours or ward GA (general admission) if out of hours.

Treatment should then be initiated as follows:

Extension set contamination / damage:

• Change set according to procedure Tenckhoff Catheter Extension Set Change
• If the exposed end of the catheter is touched, coughed or sneezed upon or cap falls off, then perform set change and advise patient to observe PD effluent for 48 hrs.
• NO further treatment is required unless signs of peritonitis.

Tenckhoff catheter damaged or punctured:

• Titanium adapter change according to procedure Titanium Adapter change.
• If the catheter has been cut too close to the exit site, the renal consultant on call MUST be contacted to discuss whether surgical review is required.

Obtain a sample of PD Fluid:  

In all cases a sample MUST be obtained following the set / titanium change and the effluent sent to bacteriology for differential white cell count (WCC), microscopy, culture and sensitivity as a once only sample.

The effluent must be visually inspected for clarity.

If the effluent is cloudy:

• Follow 'Initial management of suspected peritonitis' above.

If the fluid is clear then administer:

• IP vancomycin 30 mg/kg in 6-hour dwell up to a maximum of 3 g. 
• AND IP ceftazidime 1.5 g in 6-hour dwell
  • Both antibiotics can be given in the same bag, either Physioneal or Extraneal
• If the patient is allergic to vancomycin: use teicoplanin 15 mg/kg IP in 6-hour dwell
• If the patient is allergic to ceftazidime: use gentamicin 0.6 mg/kg in 6-hour dwell).

Once these medications have been administered and the patient remains asymptomatic, they can go home and NO further antibiotics are required. The home therapy team will follow up the patient.

The patient should be advised to: 

• Observe the clarity of the PD fluid over the next 7 days and report any change to the renal unit staff IMMEDIATELY.
• Report to the renal staff in the event of new or increasing abdominal pain.
• Wait at least 6 hours following the IP vancomycin dose before returning to their usual CAPD / APD regime.
• Automated peritoneal dialysis patients who have missed their therapy should wait six hours before carrying out 2 CAPD exchanges. Following this they may resume their usual APD regime.

• APD: automated peritoneal dialysis
• CAPD: continual ambulatory peritoneal dialysis
• IP: intraperitoneal
• LD: loading dose in mg
• MD: maintenance dose in mg

• Tenckhoff catheter: insertion and perioperative management
• Performing a CAPD bag change procedure
• CAPD fluid sampling
• Tenckhoff catheter extension set change
• Titanium adapter change
• Urokinase lock and removal in a peritoneal dialysis (PD) catheter
• Procedure for the administration of intra-peritoneal (IP) medications

• APD: automated peritoneal dialysis
• CAPD: continual ambulatory peritoneal dialysis
• IP: intraperitoneal
• LD: loading dose
• MD: maintenance dose