Complications of PD Catheters

Complications related to peritoneal dialysis (PD) catheters are hereby classified as early and late. Early complications arise within the first month after catheter implantation. Catheter-related complications often result from errors made during catheter insertion and are exacerbated by comorbid conditions and increased hydrostatic pressure generated by intra-abdominal contents. Careful evaluation of the patient, attention to the implantation technique, and rigorous care during the intra- and post-operative period can markedly prevent many of these complications.

Early Complications

Complications arising soon after catheter implantation are frequently related to the procedure itself, congenital anatomic abnormalities, and/or to increased intra-abdominal pressure (IAP) generated by infusion of dialysate into the peritoneal cavity(1).

Pain

Patients often present with mild incisional pain after the catheter insertion procedure. They may also complain of deep pain, which may be caused by traction of the bowels from catheter manipulation during the procedure. Infusion of dialysate solution can cause progressively severe pain. The three main causes of infusion pain include: 1) hypersensitivity to the low pH of the dialysate solution; 2) the placement of catheter in the functional or anatomical compartments; and 3) the position of the catheter tip against the pelvic wall, bladder, or rectum. If the pain appears to be associated with the position of the catheter tip, a shorter catheter may be used or the tip can be re-located to resolve the pain. Finally, infusion of air during catheter insertion or connection can cause transient pain.

Bleeding

A common cause of bleeding is laceration of anterior abdominal wall arteries. Arterial laceration may occur from needle insertion into the blood vessels, which can be easily detected. In such cases, removing the needle or other offending agents may be sufficient to control bleeding. Venous laceration may also occur; however, venous laceration is more difficult to recognize compared to arterial laceration due to lack of muscularis layer. For any types of lacerations (arterial or venous), prompt medical attention is needed and may require ligation through laparoscopy or laparotomy of the affected vessels. Bleeding can also occur from puncture of intra-abdominal vessel, though it occurs less frequently. Although treatment recommendation must be determined according to the severity of the bleeding, in general, frequent exchange and clotting prophylaxis with intraperitoneal heparin are commonly used until the effluent clears or surgical procedure is performed.

Perforations

Perforation of an internal organ during catheter implantation should always be considered if pain, peritonitis, or bleeding is observed. Additionally, if return of intestinal content or urine through the cathether or stylet, These signs and symptoms may be present soon after the procedure, but some patients may be asymptomatic, which results in delayed diagnosis and other complications.  Paralytic ileus or obstruction, polycystic renal disease and internal herniae are predisposing factors. The most obvious signs of perforation are: the return of intestinal content or urine through the catheter or stylet, a hissing sound from gas release, fetid smell from fecal material, instant urge to urinate or vaginal release of peritoneal fluid. Through and through perforations of the small intestine or bladder after blind insertion of the catheter may remain silent for some time after the procedure and may be associated with good initial function of the catheter, making the diagnosis more elusive. Peritoneoscopic or surgical implantation of the catheter should both reduce the incidence of perforation and provide a prompt diagnosis. Direct visualization is also helpful in deciding whether to abort the procedure and treat the patient with conservative means (i.e. antibiotic coverage and observation) or with exploratory laparotomy and repair.

Leaks

The incidence of pericatheter leaks has been variously reported to be 0 to 40%. Pericatheter leaks may not be apparent in the immediate post insertion period unless a full (2 L in adult patients) exchange is performed. Undernourished and immunosuppressed patients, diabetics and individuals with very weak anterior abdominal walls are most prone to develop this complication. Catheter leak occurrence can be minimized by precise placing the catheter cuffs and by avoiding the use of full infusion volumes, particularly in the sitting and standing positions, until the catheter is totally healed. Many clinicians recommend a rest period of several weeks after catheter insertion whenever possible to assure optimal healing.

Subcutaneous fluid leaks can migrate and cause abdominal wall or genital edema. In order to distinguish a subcutaneous fluid accumulation from a patent processus vaginalis, a scintigram or CT scan is recommended.

A leak around the internal cuff may dissect the anterior abdominal wall, causing an accumulation of fluid around the catheter incision site resembling a hernia. The diagnosis can be established by ultrasound, scintigraphy or contrast media injection into the catheter followed by drainage.

Obstruction

Outflow (one-way) is the most common type of obstruction. This obstruction is caused by the closeness of the distal portion of the catheter to the omentum or intestine, which allows infusion of the solution, but little-to-no outflow. Migration of the catheter can also cause poor outflow. Migration is associated with poor orientation of the catheter’s tunnel, resulting in misdirection of the catheter into the upper abdominal quadrants due to the catheter spatial memory(2,3). Although catheter manipulation often restores good catheter position, recurrence of migration is common and requires reinsertion with special attention to tunnel orientation. Using a titanium weight at the end of the catheter, front-loading , or laparoscopic salvage of the catheter with reposition and securing the internal tip of the catheter in the true pelvis with a stitch can prevent or correct this complication. Omental wrapping can occur at any time after catheter insertion. Conservative therapy with enemas, change in position and ambulation often remedy this problem. Persistent obstruction may require catheter manipulation with reposition or replacement in extreme cases. Surgical laparatomy or laparoscopic epiplopexy of the greater omentum and epiploic appendices has be used to salvage a dysfunctional catheter(4).

Total obstruction during insertion is probably due to a catheter kink. The problem can be resolved with manipulation using a flexible probe, or if persistent, by peritoneoscopic or surgical repositioning.  Blood or fibrin clots following implantation have also been treated with irrigations using heparinized solution. In extreme cases of a stubborn internal obstruction, direct intervention using a semi-flexible probe or brush under fluoroscopic may be required.

Infections

If peritonitis presents as an early complication, it should raise the possibility of intraoperative contamination. Polymicrobial peritonitis with gram negative organisms and/or yeasts is most suggestive of colonic perforation. If bowel perforation is suspected, the diagnosis should be confirmed and appropriate surgical intervention with removal of the infected catheter is recommended. Redness exceeding 13 mm in diameter and purulence with or without bloody discharge are signs of an acute exit site infection. Swelling, erythema, and tenderness over the tunnel tract are indications that the infection has extended to the tunnel between the internal and outer cuffs. The extent of the infection (abscess) can be further evaluated with a simple ultrasound of the anterior abdominal wall.

Herniae

Herniae may first appear following implantation of the catheter due to increased intra-abdominal pressure. The traditionally quoted predisposing factors include malnutrition, immunosuppression, multiparity and a weak anterior abdominal wall. A survey including 75 U.S. and Canadian centers analyzed the data from 1,864 patients(5). Logistic regression analysis found no association between hernias and age, body surface area, PD modality, volume of dialysate, time of largest dwell (day/upright vs night/recumbent), or type of catheter used. Cystic disease conferred a 2.5-fold increase in risk for anatomic complications (p < 0.001); female gender conferred an 80% reduction in risk (p < 0.0001), and Kt/V > or = 2.0 conferred a 52% reduction in risk (p < 0.05) for hernia.

If the diagnosis is made during the procedure, it should be immediately corrected. If not, the infusion volume should be reduced and automated PD in the supine position should be favored until corrective surgery is scheduled. Incisional herniae are more common when the incision is performed over the linea alba and least frequent with paramedian insertions through the rectus muscle.

Hydrothorax

Hydrothorax typically occurs early in the course of therapy since it is frequently due to congenital defects of muscle fibers of the diaphragm. The reported frequency varies between 1 and 10%. Diaphragmatic defects are possibly more frequent than this, but go unrecognized until fluid is present in the peritoneal cavity and intraperitoneal pressure (IAP) increases.  Women are affected more commonly than men and serous fluid predominately accumulates in the right pleural cavity.  The first manifestations of hydrothorax are dyspnea or inadequate ultrafiltration; however, approximately 25% of instances are asymptomatic and diagnosed during routine physical examination of chest x-rays. The pleuro-peritoneal communication is best localized with injection of radioisotopes into the peritoneal cavity followed by scintigrams after infusion and post drainage. A low pleural fluid protein content is the most consistent biochemical finding. The available therapeutic options include surgical closure of the communication, pleurodesis by talc insufflation, injection of oxytetracycline, autologous blood or other irritants or video-assisted thoracoscopic pleurodesis (VATS). VATS talc pleurodesis is a safe and reliable treatment that allows sustained continuation of PD with low recurrence rate(6).

Genital Edema

The most common causes of gential edema are pericatheter fluid extravasation into the preperitoneal space and a patent processus vaginalis. The latter complication frequently presents shortly after catheter insertion. The diagnosis is readily confirmed by scintigraphy, cannulography with contrast material or CT scanning. Surgical correction is most effective and allows continuation of PD in most cases.

Late Complications

Infusion pain

Pain presenting later in the course of PD suggests development of irritation due to chemical or physical causes. Localized pain during infusion often denotes irritation from the catheter tip resting against the pelvic wall or intra-abdominal organs, or from the jet created by rapid infusion of solution. If the pain persists, cannulography or other radiographic studies may be needed to assess the anatomic integrity of the peritoneal cavity. Compartmentalization from adhesion formation around the catheter, restricting flow to a small compartment causes pain and reduces clearances and ultrafiltration. Lysis of the adhesions can be done by open surgery or peritoneoscopy.

Hemoperitoneum

Hemoperitoneum is a common late complication of chronic PD, but is seldom related to the catheter. An occasional instance of bleeding is seen after tugging and pulling of a catheter with resulting internal bleeding from anterior abdominal wall small vessels. Immobilization and protection of the exit site is recommended for a few days after the event to prevent further irritation and, in most cases, usually resolves the issue. Perforation of a vascular structure from pressure necrosis is also possible (i.e., spleen), but relatively rare.

Perforation

Perforations into bowel, bladder, spleen, gallbladder, and pelvic wall due to pressure necrosis have been occasionally reported. Many of these perforations are asymptomatic and are only recognized when the fluid drains into the bladder or vagina. Effluent fluid becomes discolored with a greenish tinge. A perforation may also cause the catheter to project into the anus. The most likely predisposing cause is poor position of the catheter tip or pressure due an inadequately long catheter. Therapy consists of removal of the catheter, repair of the fistulous tract, if possible, and a rest period from PD in order to reduce intraperitoneal pressure and allow healing of the tract.

Leaks

Late pericatheter leaks occur for all the same reasons as the early ones and from persistent exit site or tunnel infections. In addition, leaks from deterioration or accidental damage to the catheter should be considered. Most catheters are made of silicon rubber or polyurethane. Hydrolysis of the polyurethane surface and cracking of the material after exposure to polyethelene glycol or alcohol has been reported. Depending on the site of the hole and the preference of the operator, the catheter can be replaced, repaired with sterile glue or simply shortened if the defect is very close to the external tip.

Obstruction

The causes, mechanisms, and therapy of catheter obstruction seen during early or late complications are very similar. The recurrent or chronic production of fibrin strands causing intermittent obstruction can be partially prevented by the use of intermittent heparin. One-way obstruction is almost always seen during the drain phase, but a reverse one-way obstruction (during infusion) has been attributed to a fibrin clot.

Infection

In addition to all the infectious complications listed in the early complications we may encounter chronic, often indolent and fastidious to treat chronic exit site infections, cuff erosions and extrusions. Many of these chronic infections are due to Pseudomonas sp, Serratiae sp or other water-borne organisms. Aggressive and prolonged specific therapy (often with two drugs) is required for eradication. Due to definite association between these exit-site infections and formation of biofilm, microabscess, tunnel tract infections and peritonitis, it is imperative to monitor the process closely during therapy and replace the catheter if no clinical improvement is observed.

Herniae

The mean time for developing herniae is 1 year after initiation of PD, with the risk increasing 20% per year for patients on CAPD. Thus, most of the herniae occur as late complications. The treatment is similar to that suggested for hernia early in the course of PD.

References

  1. Diaz-Buxo JA. Complications of peritoneal dialysis catheters: early and late. Int J Artif Organs. 2006;29(1):50-58. Available from: http://www.ncbi.nlm.nih.gov/pubmed/16485239.
  2. Diaz-Buxo JA, Turner MW, Nelms M. Fluoroscopic manipulation of Tenckhoff catheters: outcome analysis. Clin Nephrol. 1997;47(6):384-388. Available from: http://www.ncbi.nlm.nih.gov/pubmed/9202869.
  3. Hwang SJ, Chang JM, Chen HC, Tsai MK, Tsai JC, Hsu CH, Hsiao PW, Tsai CY, Guh JY, Lai YH. Smaller insertion angle of Tenckhoff catheter increases the chance of catheter migration in CAPD patients. Perit Dial Int. 1998;18(4):433-435. Available from: http://www.ncbi.nlm.nih.gov/pubmed/10505568.
  4. Crabtree JH, Fishman A. Laparoscopic epiplopexy of the greater omentum and epiploic appendices in the salvaging of dysfunctional peritoneal dialysis catheters. Surg Laparosc Endosc. 1996;6(3):176-180. Available from: http://www.ncbi.nlm.nih.gov/pubmed/8743358.
  5. Van Dijk CMA, Ledesma SG, Teitelbaum I. Patient characteristics associated with defects of the peritoneal cavity boundary. Perit Dial Int. 2005;25(4):367-373. Available from: http://www.ncbi.nlm.nih.gov/pubmed/16022094.
  6. Tang S, Chui WH, Tang AWC, Li FK, Chau WS, Ho YW, Chan TM, Lai KN. Video-assisted thoracoscopic talc pleurodesis is effective for maintenance of peritoneal dialysis in acute hydrothorax complicating peritoneal dialysis. Nephrol Dial Transplant. 2003;18(4):804-808. Available from: http://www.ncbi.nlm.nih.gov/pubmed/12637652.

P/N 102515-01 Rev A 07/2016