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 intraabdominal organs, or from the jet created by rapid infusion of solution. If the pain persists, cannulography or other radiographic studies are indicated 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 ultrafiltration1. 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 per se. An occasional instance of bleeding is seen after tugging and pulling of a catheter with resulting internal bleeding from and 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. No other action is necessary in most instances. Perforation of a vascular structure from pressure necrosis is also possible (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 only recognized when the fluid drains into the bladder or vagina, effluent fluid becomes discolored with a greenish tinge from ble, or the catheter makes a surprise appearance through 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. 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.
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 have been reported (see Evolution of PD Catheters).
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 i.p. One-way obstruction is almost always seen during the drain phase, but a reverse one-way obstruction (during infusion) has been described due 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, Serratiae or other water-borne organisms. Aggressive and prolonged specific therapy (often with two drugs) is required for eradication (see Exit Site Infections). 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 conservative therapy and replace the catheter if no clinical improvement is observed.
Cuff position during catheter placement is critical. If the external cuff is placed too close to the exit site (<1.5 cm) or if the exit site is too large (exceeding the diameter of the catheter), there is a high risk of cuff extrusion. Very superficial placement of the cuff, particularly in thin patients with scant subcutaneous fat, positioning the cuff directly under the belt line or repeated exit site infections can result in cuff erosion. Once again, unroofing the area, surgical debridement and shaving the external cuff can correct the problem. However, the only way of curing the problem is total or partial replacement of the catheter and selection of a new virgin exit site.
Herniae, genital edema. 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.
Back to Complications of PD Catheters
References:
- Diaz-Buxo JA. Peritoneal dialysis catheter malfunction due to compartmentalization. Perit Dial Int 17: 209-210, 1997