University Hospital of Wales, Heath Park, Cardiff, UK
Abstract
Background. Tenckhoff catheters are used widely for the provision of continuous ambulatory peritoneal dialysis. Traditionally these catheters are removed surgically under anaesthesia. We set out to introduce and monitor prospectively a technique for removal of the Tenckhoff catheter by a pull technique. The intention was to avoid the discomfort, risk and cost of traditional surgery.
Methods. Over a 1-year period all renal transplant patients having their Tenckhoff catheter removed by this technique were monitored prospectively. All patients were followed for a minimum 2-year period after removal. In the pull technique steady non-jerky traction is applied to the catheter. Complications such as catheter breakage and cuff related sepsis were recorded.
Results. Sepsis related to a retained cuff occurred in only one patient early in the series. There were no other complications. The procedure was well tolerated. Use of local anaesthesia used initially, was largely phased out over the course of study and the procedure moved from the theatre to the ward.
Conclusions. The pull technique is safe and well tolerated. The technique has significant advantages in selected patients without a history of recent peritonitis or exit site infection, in reducing risk to the patients, the pain of abdominal wall surgery and reduced usage of costly theatre time and in-patient beds.
Keywords: anaesthesia; complications; cost; pull technique; removal; surgery; Tenckhoff; transplantation
Introduction
Tenckhoff catheters (Quinton, Seattle, WA, USA) are used widely for the provision of continuous ambulatory peritoneal dialysis (CAPD). These catheters are implanted surgically and are retained in the patient by tissue in-growth into two cuffs. After successful transplantation these catheters can be removed. Traditionally this has been by surgical exposure, dissection of the cuffs from the scar tissue and removal in entirety. This procedure can be accomplished in the operating theatre under a general anaesthetic or with more difficulty under local anaesthetic. This activity exposes the patient to the pain of surgery to the abdominal wall and risks of anaesthesia. This activity also takes up precious beds, medical, nursing and theatre time. In our unit we have not performed this surgery for years. However, we can find little reference to alternatives in the literature and on enquiry find that almost all units continue to remove Tenckhoff catheters surgically. Therefore, we chose to review our technique for removal of catheters prospectively and follow a group of patients for some years to assess the efficacy of a pull technique.
Subjects and methods
Over a 1-year period all renal transplant patients having their Tenckhoff catheter removed by this technique were monitored prospectively. All patients received triple therapy immunosuppression consisting of cyclosporin, azathioprine, and prednisolone. Data were recorded for prior history of infection, time catheter in situ, time catheter in situ post-transplantation, place where the procedure was performed, anaesthesia used, technique used, and complications. All patients were followed for a minimum 2-year period after removal.
The commonest catheters have two cuffs bonded to the catheter itself. However, this bond is not particularly strong. This provides a safe guard as the catheter will always shear from the cuff rather than break in the event of an accident. In the pull technique, steady non-jerky traction is applied to the catheter. Anaesthesia or sedation is not usually required (see below). The catheter will stretch and pressure will be felt by the patient at the outer cuff. After a few moments the catheter will begin to move out again as the cuff shears off and is retained in the patient. Tension is now transferred to the inner cuff. Traction is maintained as before and the inner cuff will separate from the catheter. The intra-peritoneal section of the catheter is drawn through the cuff and the intact catheter removed from the patient.
The technique is modified in some situations. If there is a history of recent exit site infection local anaesthesia is injected at the exit site. The exit site is enlarged a little. Traction brings the cuff to the base of this small wound. Local anaesthetic is injected around the outer cuff and the cuff dissected from the surrounding tissues. The rest of the catheter is removed by traction leaving the inner cuff as before. In the absence of infection, if the outer cuff on traction is found to be right next to the skin it is removed as above.
Results
Thirty-one patients (17 male and 14 female) underwent removal of their Tenckhoff catheter by this technique and have been followed for a minimum of 2 years.
The mean age was 44 years. The mean time catheter was in situ prior to removal was 24 months while the mean time in situ post-transplant was 4 months. Anaesthetic techniques used included: 15 local alone; three local plus sedation; eight no anaesthetic; three general anaesthetic (in patients undergoing another procedure); two sedation for anxiety. Twenty-five catheters were removed in the operating theatre and six on the ward. The inner cuff was retained in 31 patients. The outer cuff was retained in 26 and removed in five patients. Mean time in hospital was 0.5 days. Complications included late outer cuff related infection in one patient. Neither deep cuff sepsis nor catheter breakage occurred.
Discussion
We have shown that the pull technique is effective for Tenckhoff catheters removed post-transplantation, and adoption of this technique would represent a major change in practice in most units. However, some units use other catheters such as the Oreopoulos-Zellermann Catheter, which would not be suitable for this procedure. Only one other paper makes reference to a procedure to minimize the invasiveness of the removal of Tenckhoff catheters [1]. In this paper the authors report a technique that still involves anaesthesia and removal of both cuffs. In the literature and in transplant centres, there seems to have been little attempt to challenge the conventional removal by formal dissection and excision of the catheter. In the only other paper in the literature using a similar technique to ours [2] infection at the retained cuffs did occur in 24% of cases. The author's conclusion was to dismiss the procedure on this basis. Importantly, their results relate to a study group of renal failure patients many with CAPD peritonitis, who would be expected to have a particular risk of sepsis [3]. The majority of their infections were in the superficial cuff, as demonstrated by ultrasound, and this would have been simple to resolve by surgery or may have been prevented by following our policy regarding the removal of superficial outer cuffs. We have confined this study to immunosuppressed renal transplant patients having the CAPD catheter removed after successful transplantation. These patients had no significant recent history of infection and hence ultrasound was not used. We chose to wait for a long period of follow-up as there was concern regarding the potential for late cuff related infection. However, sepsis was not a significant complication in our immunosuppressed renal transplant population. The single case of infection was early on in the series and was related to a very superficial external cuff. After this case, all patients with a very superficial cuff had this excised as described above and no further events were seen in the series.
It follows that in patients on CAPD where the catheter needs to be removed for malposition, failure of creatinine clearance or a change to haemodialysis, we would suggest that it is also safe to use the pull technique.
In our series there was some variability in the time to catheter removal. The mean time post-transplantation, was 4 months with a range between 2 and 19 months in a patient with long-standing suboptimal renal function post-transplantation. Since the study period all the catheters are pulled 3 months post-transplant, if the renal function is stable.
We have had no cases of catheter breakage. Should this complication occur the break would be expected to occur at the junction of the catheter and the inner cuff. Hence, even in this theoretical situation the intra-peritoneal section would remain anchored to the abdominal wall and could be removed by reverting to the standard surgical exposure and removal. A catheter that has been in place for a long time could be a contraindication for the use of the pull technique. In our series, the longest a catheter had stayed in situ prior to removal, was almost 5 years with a mean time of 2 years. It is possible that time might affect the strength of the material the catheters are made of and this should at least be considered when contemplating the pull technique in this situation.
We have not found that anatomical differences between patients make the procedure any harder. In obese patients the outer cuff is anchored to fat and the cuff is well isolated from the skin and possible infections. In the very thin patient with little adipose tissue, the outer cuff anchors itself to the dermis, making the pull more painful. In these cases it is possible to infiltrate some local anaesthetic around the palpable cuff and excise it before the pull technique is used for the inner cuff.
With regard to anaesthesia, as the series progressed it became clear that this was not required. Hence, the patient is not exposed to the hazards of anaesthesia. Patients tolerated the procedure well and there is little difference between the sensation associated with the pull and removal of drains or central lines for example. We now perform the pull procedure on the ward in a treatment room. Hence these patients do not have to be formally admitted even as a day-case. This has released theatre time for more useful activity. The costs of a theatre time, anaesthetist and inpatient bed are all removed. Our theatre manager has estimated that this has saved £17 000 for the 31 patients.
In conclusion, we have found that a simple procedure, in selected patients, can replace the surgical technique for the removal of Tenckhoff CAPD catheters with minimal complications. The pull technique has become standard practice in our unit since this study was performed without any morbidity or mortality to this time.
Notes
Correspondence and offprint requests to: Dr Isabel Quiroga, Transplant Centre, Churchill Hospital, Headington, Oxford OX3 7LJ, UK. Email: isabelquiroga{at}hotmail.com
References