Long-term experience with the Thomas Shunt
Editor's note Please see also editorial note by Bommer pp. 17611762 and original article by Coronel et al. pp. 18451849.
Gerhard Krönung
KLN-Kreiskrankenhaus, Ottweiler, Germany
Coronel et al. (pp. 18451849) present a retrospective study of 27 Thomas shunts (TS), all of them implanted in femoral vessels. TSs were used, when creation of a permanent vascular access (Cimino or E-PTFE) was impossible. Average duration of function and the complication rates were much better than those of jugular catheters and even better than those of E-PTFE grafts. Permanent anticoagulation was given without indicating drugs and dose. The number of TSs per patient ranged from one to nine. In conclusion the authors describe TS as a better solution of vascular access problems than jugular catheters when it is not possible to perform a permanent vascular access. Five comments should be made:
- (1) The study takes into account only TSs functioning for more than 3 months. Therefore the results are not comparable with other studies, which usually consider all procedures of the time period studied. How many TSs functioned for less than 3 months in the study period?
- (2) TS was only implanted when no regular shunt was possible. This is unintelligible. Femoral vessels, which can be anastomosed with the Dacron patch of the TS can be anastomosed the same way with an E-PTFE graft.
- (3) The operation procedure is much more aggressive and time consuming than the placement of a jugular catheter especially when repeated procedures in the same region are necessary. Because the prostheses are wear resistant, complications occur at the anastomosed vessels. How large-scale were the reconstructions of the involved vessels and what techniques were used, when repeated TS implantations in the same region were necessary?
- (4) Although both access types (jugular catheter and TS) are external shunts, the comfort for the patient with a soft jugular catheter with skin exit below the clavicula is much better than with TS (e.g. bathing and other bodily activities).
- (5) The results of external shunts are dependent on the experience and skill of all persons involved (surgeon, nurses, patient). I remember the time in the middle of the 1980s, when continuous arteriovenous haemofiltration without blood pump required a Scribner shunt. Many Scribner shunts were implanted without the experience of the 1960s, with horrible results. And this is the same problem nowadays with the TS. The number will always be very small, so that extensive experience cannot be gained.
Summarizing, the TS may achieve good results in the hands of the experienced surgeon and dialysis staff in single cases. The indication must be formulated clearly. To cover a short time period (14 months) the procedure and the vessel trauma is too aggresive. For longer time periods TS has to be compared not with a jugular catheter but with an E-PTFE graft with similar or better cumulative results and much more comfort for the patient. If one has experience with this access type there may remain a small number of indications that cannot be defined commonly but decisions must be taken in these special situations from case to case.
Notes
Correspondence and offprint requests to: G. Krönung, KLN-Kreiskrankenhaus, Postfach 1351, D-66564 Ottweiler, Germany. 