PERITONEOSCOPIC PLACEMENT OF THE TENCKHOFF CATHETER: FURTHER CLINICAL EXPERIENCE Stephen R. Ash*,*** Alan E. Handt** Richard Bloch*** SUMMARY In the past two and one-half years, 80 Tenckhoff peritoneal catheters have been placed by peritoneoscopic technique using a NeedlescopeR with a surrounding catheter guide. Peritoneoscopic inspection of the abdomen (after filling with one liter of air), allows placement of the catheter guide in a space free of omental involvement or adhesions. The catheter guide then allows the same small hole used for peritoneoscopy to be gently enlarged to the Tenckhoff catheter size. Of the 80 catheters placed, only three have encountered early failure, one of which was corrected by repositioning (3% early failure rate). Follow-up of catheters placed in chronic dialysis patients showed a half life of 17 months (by actuarial table). Late problems of cuff erosion, outflow obstruction after peritonitis, and cuff infection occur as with Tenckhoff catheters placed by standard techniques. Our experience indicates that early success of the Tenckhoff catheter is improved by peritoneoscopic placement. *Hemodialysis Laboratory, Purdue University, West Lafayette, IN **8t. Vincent's Hospital, Indianapolis, IN ***Arnett Clinic, Lafayette, IN The widespread use of peritoneal dialysis owes its success, in part, to the longevity of the Tenckhoff peritoneal access device. In comparison to standard intravenous lines, this device has remarkable biocompatability and resistance to subcutaneous infection. In spite of the overall success of the catheter, instances of outflow failure or leaks are seen in every dialysis center. Early failure rates from 10 to 38% have been reported in adults and failure rates appear to be much higher in children (1-3). Presently, 10% of all hospital admissions for patients on CAPD are due to catheter infection, migration or obstruction (4). According to Tenckhoff, proper outflow characteristics of the catheter are obtained only if it is placed in the (potential) space between the bowels and anterior abdominal wall. Preferably the catheter should be placed in the left lower quadrant (5). In this location. outflow obstruction is minimized, although occasionally still present. Even when optimally placed, the Tenckhoff catheter has a variable outflow rate, and the rate diminishes as the peritoneal space is drained (Fig. 1). Complete outflow obstruction, when it occurs, may be due to catheter involvement with the omentum ( especially after peritonitis), placement between bowel loops, or physical occlusion by fibrin (6). The common methods of Tenckhoff catheter placement i.e. by trocar or laparotomy, both have shortcomings. When using the trocar, the abdomen is prefilled with two to three liters of dialysate, and then the catheter is advanced blindly into the peritoneal cavity. The infusion of dialysis fluid into the abdomen does not assure that a clear space between bowels and abdominal wall will be opened (some bowel loops will float, and some will sink). Therefore, the physician may encounter some resistance in advancing the catheter to its full length, and for this reason, the pre-abdominal cuff may not come to lie in tight apposition to the abdominal wall. In surgical placement, the peritoneal surface is clearly identified. but in examination of the peritoneal cavity, the surgeon is limited by the necessity of a relatively small (one to two cm) incision of the peritoneum. The abdomen is not prefilled, and resistance to the advancement of the catheter is not uncommon. Postplacement leakage of dialysate is relatively common, if the catheter is used within three weeks of placement (up to 42%) (7).Early outflow obstruction and catheter migration are common after both procedures. In 1981 (8) we described a procedure for placement of the Tenckhoff catheter that included five unique features: 1. Confirmation of the intraperitoneal location of the first cannula entering the abdomen. 2. Use of air, rather than dialysate, for opening a space in the anterior peritoneum.
3. Selection of the optimal catheter path, and sizing of the length of such path under direct vision, using a 15 cm long, 2.2 mm diameter NeedlescopeR. 4. Placement of the catheter through the same small hole used for the NeedlescopeR. After the peritoneoscopy procedure, the guide is left in the desired catheter path, and the peritoneal hole dilated to a size which will snugly fit the Tenckhoff catheter. 5. Positive placement of the pre-peritoneal cuff against the abdominal wall, during advancement through the coiled catheter guide. The 1981 report described the placement of catheters in 10 patients. The initial results indicated that the NeedlescopeR/catheter guide technique allowed successful catheter placement in patients in which blind techniques might be difficult (8).Subsequently, the procedure has been used to place 80 Tenckhoff catheters. This report describes our further clinical experience with the procedure. METHODS In the past two years, we have routinely used the peritoneoscopic method for Tenckhoff catheter placement. Patients were offered the choice of this method of placement, or surgical placement. Of 80 patients who chose peritoneoscopic placement, 50 were individuals with endstage renal failure, beginning chronic peritoneal dialysis treatment. The rest were acute renal failure patients with a variety of initiating causes. Many of the patients had relative contraindications to "blind" placement, including known adhesions or abdominal prostheses (colostomy). Catheter placement was performed in a treatment room, ICU, or dialsyis unit. Sterile drapes, gowns, masks, etc., were used and the abdomen carefully prepped. Generally, the patients were premedicated with 25 75 mg of Demerol, but were awake during the procedure. The site chosen was the midline, right lower or left lower quadrant. A summary of the procedure is as follows: After suitable local anesthesia of the skin, a 2 cm vertical skin incision is made at the desired location of catheter entry to peritoneum. Blunt dissection is performed to the abdominal wall, using a hemostat. The Needlescope* utilized has an optical portion 15 cm long and 2.2 mm diameter, with a 17 inclined tip. A Tungsten light source is attached to the NeedlescopeR by a flexible guide light. This NeedlescopeR is the same length from hub to tip, as the distance from pre-peritoneal cuff to the tip of the standard Tenckhoff catheter. The NeedlescopeR and all accompanying equipment are gas sterilized, except for the sphygmomanometer bulb used for air insufflation, which is steam sterilized. Figure 2 indicates the seven basic steps of the procedure. Before puncture of the peritoneum, three parts are assembled: A pointed trocar (2.2 mm diameter), cannula (2.8 mm O.D., stainless tube), and a catheter guide (thin, slotted polypropylene tube, which is heat -set in a 3 mm coil). Figure 2a indicates the first step of this assembly. A pointed tab on the catheter guide is inserted through a slot at the end of the cannula, from inside out. In Figure 2b, t he catheter guide is folded backwards, and wrapped around the cannula. In Figure 2c, a sharp, 2.2 mm diameter steel trocar is advanced within the cannula, locking the tab in place on the cannula. A retaining ring (polyethylene tubing, 3 mm I.D.) is advanced around the catheter guide, further securing it to the cannula. This assembly is then advanced blindly into the peritoneum, at the desired catheter position, using a slight twisting motion as with an acute peritoneal dialysis catheter. Such entry is done with more ease than with the acute dialysis catheter, since the diameter of the cannula and trocar is less than 3 mm. After the initial insertion of these parts, the trocar is removed and the NeedlescopeR is inserted in its place (Fig. 2d). With low light intensity (Tungsten lamp), the local peritoneal surface may then be inspected. The *NeedlescopeR and pre-sterilized catheter placement tray are available from Medigroup Inc..248 S. Highland. Aurora. IL 60506.
presence of highly reflective, vesselcovered surfaces, which move during respiration, indicates the proper intraperitoneal location of the cannula and catheter guide. The NeedlescopeR is then withdrawn, leaving the cannula and catheter guide in position, and air insufflation is performed using the steamsterilized sphygmomanometer bulb. Thirty compressions of the bulb result in about 1 L insufflation. A slight "thrill" can be felt on the cannula, as air passes into the peritoneal space. The patient should not sense any pain during insufflation. After insufflation, the NeedlescopeR is inserted again (as in Fig. 2d). The NeedlescopeR, with its surrounding cannula and catheter guide, is then advanced into the furthest comer visible of the air space in the lower abdomen (usually, left lower quadrant). Adhesions between omentum or bowel and abdominal wall are clearly visualized and avoided. The NeedlescopeR is advanced until its hub stops at the abdominal wall, or until contact is made with the distant comer of the visceral and parietal peritoneum (Fig. 2d). If the peritoneal air space does not allow full advancement of the scope, the patient is placed in Trendelenburg position (head 15 cm lower than feet). If the air space still does not allow insertion of the 15 cm scope, the Tenckhoff catheter is shortened (using scissors) by the distance by which the hub falls short of the abdominal wall. After the NeedlescopeR and cannula are advanced as far as possible, the scope is removed from the cannula. The cannula and retainer ring are then removed, leaving the guide in the same path previously occupied by the NeedlescopeR (Fig. 2e). The portion of the catheter guide within the abdominal wall is then dilated with short, 4 mm and 6 mm diameter, round-tipped rods. A rounded steel obturator is then placed within the Tenckhoff catheter (to within 2 cm of the tip), for purpose of rigidity. The catheter is then inserted into the catheter guide, with the catheter tip advancing inside the guide, and the cuff protruding through the slot (Fig. 2f). The cuff thus follows outside the guide and the tip remains inside the guide, entering the abdomen. The catheter is advanced until firm resis tance is met, indicating that the cuff has reached the anterior abdominal wall (Fig. 2f). The catheter guide is then removed, while holding the Tenckhoff catheter stationary (Fig. 2g).The slot in the guide allows it to widen around the catheter, without affecting the catheter or cuff position. The obturator is then removed from the catheter. (NOTE: If it is desired to place the pre-peritoneal cuff within the abdominal wall, the wall may be dilated, after anesthetization, by hemostats advanced into the catheter guide). The subcutaneous tunnel of the Tenckhoff catheter is then made, in a direct line with the intra-peritoneal portion of the catheter (towards the right upper quadrant, if the catheter is in the left lower quadrant). This may be performed with a uterine sound, but may also be done using the same catheter guide used above. To create such a tunnel using the catheter guide, the catheter guide, trocar, and cannula are assembled as in Figure 2c. The desired skin exit site is then determined by laying the Tenckhoff catheter on the skin, and marking a site 2 cm distal to the subcutaneous cuff. The exit site is then anesthetized. The cannula, trocar, and catheter guide are inserted into the
subcutaneous tissue at the edge of the primary incision, towards the desired skin exit -site. A stab incision through the exit site is made, with a pointed scalpel. The cannula and trocar are then advanced through the stab incision. The cannula and trocar are removed, leaving the catheter guide in place. The pointed end of a closed hemostat is then inserted through the primary incision into the catheter guide. The hemostat is then expanded, its ends leaving the catheter guide through the slot. Several such expansions can create a I cm diameter tract for the subcutaneous cuff to pass through. This dilation is painless, if the course of the catheter guide avoids skin or muscle. The free end of the catheter is then inserted into the catheter guide, and the guide and catheter pulled through the skin exit-site. The catheter is then pulled through the exit -site until the subcutaneous cuff reaches the desired position. Creation of the subcutaneous tunnel does not alter the position of the pre-peritoneal cuff. After pulling the catheter through the skin exit, a tubing connector is attached to the catheter and 2 L of dialysis fluid is infused into the abdomen. The primary incision is inspected for evidence of leak around the Tenckhoff catheter at this point (not seen in any of our patients). The subcutaneous tissue is then closed with absorbable suture, if desired, and the skin is closed with either nylon or silk suture. The catheter may be used immediately for supportive peritoneal dialysis. Machine automated IPD is used for some patients (1.5 L exchanges), three times weekly. In other patients, a CAPD schedule is begun with four exchanges per day of 1.5 L dialysis fluid. Complete drainage of the abdomen is performed each night, and a small ViaflexR bag attached to the patient line. For immobile, acute renal failure patients, continuous equilibrium peritoneal dialysis with two liter exchanges is possible. RESULTS In each of the 80 placement procedures, it was possible to determine a clear space for catheter placement in the peritoneum. Numerous adhesions were seen in the peritoneal spaces of these patients, but it was possible to avoid such adhesions during advancement of the NeedlescopeR. Ten patients were found to have adhesions in the left lower quadrant or midline area (related to previous operations and catheters, in most). In these cases, the catheters were directed into other intraabdominal locations (generally right-lower quadrant, but right-upper and leftupper quadrant in two cases). The catheters placed in the upper quadrants worked well, with unimpeded drainage. Two Tenckhoff catheters were placed in patients with an ostomy (ileostomy or colostomy). There was little difficulty in avoiding the internal ostomy site, and there were no early catheter problems in these patients. During the initial filling of the abdomen with 2 liters dialysis fluid, there were no gross pericatheter leaks. One subcutaneous leak occurred later, in an obese patient, who previously had developed leaks around an acute catheter. Several catheters were placed in obese patients, over 130 kg. Of the 80 catheters, all but three functioned well initially. These three had evidence of outflow obstruction in the first few exchanges. Of these, one responded to repositioning with a Foley catheter guide; during repositioning it appeared that the catheter had folded within the abdominal cavity. Overall, early function was successful in 97% of placements. There were no catheter infections or episodes of peritonitis immediately following placement. Twenty-six of the catheters placed by NeedlescopeR/catheter guide were in patients initiating chronic renal failure therapy at one of the hospitals. Catheter longevity has been analyzed for these patients, and is presented in Fig. 3. During the period of follow-up of these catheters, there were six late catheter failures, due to the usual variety of problems: Cuff erosion, subcutaneous infection, late outflow obstruction, and persistent peritonitis. In addition, two hernias developed around the catheter insertion site ( each 2 x 2 cm). The failure rate of the catheters (overall) was one per 34 patient months. However, a number of patients in this population were fol lowed for six months or less. Since catheter failure is not a random event, the overall incidence of failure does not accurately reflect expected incidence of failure for individual catheter. Actuarial analysis of the catheter longevity was performed (as in Ref. 9). Catheter failures/patient-months at risk was determined for monthly intervals. By this analysis, the halflife of NeedlescopeRplaced catheters was 17 months. Also presented in Fig. 3 is experience with some surgically implanted catheters. These catheters were placed before the routine use of the NeedlescopeR/catheter guide procedure, or later, in patients who preferred the surgical placement procedure. Two of eleven of these catheters failed due to outflow failure or catheter infection. It appears that late complications of the Tenckhoff catheter are not totally avoided by the NeedlescopeR/catheter guide technique, and are probably similar in frequency to surgically placed catheters. DISCUSSION While this placement procedure may appear to be complex, it is readily learned by physicians with experience in medical placement of acute or chronic catheters. The total time for the procedure is 20 to 30 minutes. A saving
in time is afforded by use of air insufflation rather than fluid instillation (2 to 3 liters of dialysis fluid infusion may require 10 to 20 minutes). A further savings in time results from avoiding the need for mobilization of a surgical team for catheter placement. Performing the procedure in a treatment room (rather than operating suite), and immediately instituting peritoneal dialysis offers advantages to the patient with acute renal failure. In chronic dialysis patients, the development of peritonitis or catheter infection are indications for removal of a Tenckhoff catheter. The decision to remove a catheter is easier to make, if the Nephrologist can place a new catheter with a high probability of success, and use it immediately for supportive dialysis. A surprising finding of our work has been the variety of intraperitoneallocations in which the Tenckhoff catheter can work if bowel and omentum are avoided during placement. With catheters placed in upper quadrants, successful drainage can occur, obviously by the siphon effect. Peritoneoscopic inspection of catheters which have mi grated upwards, indicates that these are usually firmly encircled by omentum and bowels. It is this complication which probably results in outflow failure, rather than the elevation of the catheter. In conclusion, the peritoneoscopic catheter placement technique improves the accuracy of placement of the Tenckhoff catheter and minimizes the size of the peritoneal hole. Using this technique, one can place catheters in patients with previous abdominal operations and intraabdominal adhesions, and avoid bowel involvement. Pericatheter leak of dialysate is rare (1/80) and the 97% early function rate is superior to the success rate reported by centers using trocar or surgical placement. Immediate supportive dialysis is possible with this technique without excessive leaks. Late catheter problems such as infection, leak, or pericatheter hernias may still occur, and catheters placed by this technique show a survival rate similar to that of catheters placed surgically (half-life = 17 months in this study). REFERENCES 1. Karanicolas S, Oreopoulos DG, Pylypchuk G et al. Home peritoneal dialsyis: Three year's experience in Toronto. Can Med Assoc I 1977;116:266. 2. Giordano C, DeSanto NG, Papa A et al. Short daily peritoneal dialysis. Kidney Int 1975;7:S425. 3. Rubin I, Adair C, Raju S, Bower I. Complications of the Tenckhoff catheter (abstract). ASAIO 1982;11:63. 4. Counts S, Hickman R. Garbaccio A, Tenckhoff H. Chronic home peritoneal dialysis in children. Trans Am Soc Artif IntemOrgans 1973;19:167. 5. Tenckhoff H. Peritoneal dialysis today: A new look. Nephron 1974:12:420. 6. Oreopoulos DG. Renewed interest in chronic peritoneal dialysis. Kidney Int 1978;8:S117. 7. Gutman RA. Catheter complicationsimplications for choosing one or two cuffs. Proc 2nd Ann CAPD Conf, Kansas City, MO 1982:160. 8. Ash SR, Wolf GC, Bloch R. Placement of the Tenckhoff peritoneal dialsyis catheter under peritoneoscopic visualization. Dial & Transplant 1981; 10:383-386. 9. Ponce SP, Pierratos A, Izatt S et al. Comparison of the survival and complications of three pennanent peritoneal dialysis catheters. Perit Dial Bu111982; 2:82-86.