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G Kretschmer

Publications and source records attributed to G Kretschmer.

At least 91 records · Page 5Linked to original sources

[Role of postoperative anticoagulant treatment following femoro-popliteal venous bypass. Interim evaluation of a controlled clinical study].

Eighty-eight patients underwent a classical reversed saphenous vein graft for femoro-popliteal occlusive disease and were enrolled in a controlled clinical trial. During the second postoperative week the patients were allocated randomly into one of two groups: group I consisted of 42 patients who received dicumarol and group II (46 patients) served as a control group without any anticoagulant treatment. The mean follow-up time was 24 months. After 12 months the cumulative patency rate was 82%, after 18 months 76% and after 24 months 76%; for patients receiving dicumarol treatment the respective figures were 92%, 86% and 86% and for those with no treatment 70%, 67% and 67%, the difference being significant. When the bypass operation was performed for limb salvage (clinical stages III and IV) the overall results were worse (12 months: 72%, 18 months: 68%, 24 months: 68%) than in stages II, II-III (12 months: 90%, 18 months: 85%, 24 months: 85%). In limb salvage surgery the positive effects of anticoagulant treatment were significant (with treatment: 12 months 87%, 18 months 86%, 24 months 86%; without treatment: 12 months 58%, 18 months 54%, 24 months 54%).

Aged↗

The place of profundaplasty in the surgical treatment of superficial femoral artery occlusion.

One-hundred and sixty-three patients in whom an isolated profundaplasty was performed as treatment for superficial femoral artery occlusion were evaluated for postoperative improvement, taking into consideration the degree of stenosis of the profunda origin and the patency of peripheral vessels. One-hundred and eleven (68.1%) patients achieved clinical improvement. Fifty-two patients had to undergo amputation (27 below the knee and 19 above the knee) or distal reconstruction (6 patients) because of unrelieved ischaemia. In patients with Fontaine stage II and III disease (89% and 70% respectively) improvement was observed more often than in those with stage IV disease (53%). Half of the patients had an increase of the resting systolic ankle-brachial arterial pressure index, but the rise was only slight (0.12 +/- 0.1). While radiological information of the presence and degree of a stenosis had little influence on the operative outcome stenosis at the origin of the profunda, when seen and described at operation, resulted in a more frequent improvement in the clinical state and systolic ankle-brachial arterial pressure index. A patent popliteal artery was not necessary for a favourable outcome but the number of patent tibial arteries was important. Whenever two tibial vessels were patent, relief was achieved in 75% of the cases: the existence of one patent tibial artery produced improvement in 64% but if all were occluded only 31% showed improvement. In cases of severe ischaemia, success following profundaplasty is limited and the results are often inadequate. If at least one tibial artery is patent, the alternative is a femoro-crural reconstruction.(ABSTRACT TRUNCATED AT 250 WORDS)

Amputation, Surgical↗

The influence of anticoagulant treatment on the probability of function in femoropopliteal vein bypass surgery: analysis of a clinical series (1970 to 1985) and interim evaluation of a controlled clinical trial.

During the years 1970 to 1985, 463 patients with obliterative atherosclerosis at the femoropopliteal level underwent elective surgery. The operation performed was an autologous saphenous vein bypass using the reversed technique. The vascular surgical treatment was documented in reasonable detail (both baseline and follow-up) in accordance with the documentation system of the Austrian Society of Vascular Surgery. On-line data entry with use of SAS data-base management software was used. The patency curves were estimated in accordance with the Kaplan-Meier method; possible differences were checked by means Breslow's and Mantel's tests. The preoperative clinical status (claudicants, n = 200; limb salvage, n = 263) influenced the postoperative results in a statistically significant manner (Breslow p less than 0.01; Mantel p less than 0.03). All the other risk factors analyzed (site of distal anastomosis above versus below the knee, n = 231, and n = 232, respectively; Breslow p less than 0.58, Mantel p less than 0.58. Presence [n = 122] or nonpresence [n = 341], of diabetes mellitus [Breslow p less than 0.77, Mantel p less than 0.68]; smoking habits [nonsmokers, n = 93, smokers n = 370, Breslow p less than 0.68, Mantel p less than 0.69;]) did not reach statistical significance. Anticoagulant treatment (n = 101) had no effect (Breslow p less than 0.93, Mantel p less than 0.72), even when the therapy was restricted to cases with disease at advanced clinical stages (stages III, IV; n = 50; Breslow p less than 0.55, Mantel p less than 0.95). On the basis of these analyses, a prospective trial was initiated in 1979. Eighty-eight patients were studied; those in group I (n = 42) received dicumarol, and those in group II (n = 46) were controls who did not receive anticoagulant treatment. At present, the median follow-up time is at 30 months. Treatment with dicumarol favorably influenced graft patency (Breslow, p less than 0.03, Mantel p less than 0.07; one-tailed tests). The patients' preoperative clinical status affected the results of surgery (Breslow p less than 0.03, Mantel p less than 0.02; one-tailed tests). In relation to the preoperative clinical status, a therapeutic effect was observed in stages III and IV (n = 45; Breslow p less than 0.03, Mantel p less than 0.07; one-tailed tests), while no effect of therapy was demonstrable in claudicants (n = 43; Breslow p less than 0.3, Mantel p less than 0.4; one-tailed tests).(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗

Prevention of nephrotoxic cyclosporine peak concentrations by daily drug division in 3 equal oral portions.

Nephrotoxicity is the main side effect of cyclosporine therapy. In this study 2 groups consisting of 6 kidney transplant recipients were investigated. The oral cyclosporine daily dose was in the first group 13 mg/kg, in the second 11 mg/kg, respectively. In both groups, the daily dose was divided on the first day of investigation in 2 equal portions given at an interval of 12 hours. On the second day, the same dose was divided in 3 equal portions given at an interval of 8 hours. After cyclosporine administration twice a day very high blood cyclosporine peak concentrations (two to three times higher than the therapeutic range) were measured. These potential nephrotoxic cyclosporine concentrations could be prevented by cyclosporine application in 3 equal portions. A reduction of the daily dose in the early period after kidney transplantation to a starting daily dose of 12 mg/kg or even 10 mg/kg can be recommended.

Adult↗

[Autologous venous bypass in the therapy of arterial occlusive disease of the femoropopliteal area: long-term results].

The outcome of 532 femoro-popliteal vein grafts performed electively during the years 1970 to 1985 for obliterative arterial disease, was analyzed using the documentation-system of the Austrian Society for Vascular Surgery, as well as SAS and BMDP-software on an IBM 4381 computer of the Medical Faculty. The probability of function was estimated according to the Kaplan-Meier method, statistical differences were checked with Breslow's and Mantel's test, the proportional hazards regression model (Cox) was used to elucidate the influence of different risk factors on each own and in combination of each other. In the univariate analysis, the preoperative clinical status was found to be of prognostic significance, but technical details such as intraoperative as well as postoperative arteriography or site of the distal anastomosis were not important. A postoperative coumarine treatment had no demonstrable impact on graft function, but positively influenced the probability of patient survival. Taking into account the factors found to be of significance in the univariate analysis (e.g. set of factors: site of distal anastomosis, diabetic state and smoking habits) were analyzed using the proportional hazards regression model but were found of no major influence. The factors preoperative clinical status, patients age, and coumarine therapy significantly influenced the probability of patient survival, but diabetes mellitus and smoking were found to be not important.

Aged↗

Influence of anticoagulant treatment in preventing graft occlusion following saphenous vein bypass for femoropopliteal occlusive disease.

Seventy-one patients underwent a classical reversed saphenous vein graft for femoropopliteal occlusive disease and were enrolled in a controlled clinical trial. During the second postoperative week the patients were allocated randomly into one of two groups; group 1 consisted of 34 patients who received coumarin, group 2 (37 patients) served as a control group without any anticoagulant treatment. The mean follow-up was 18 months. After 12 months the cumulative patency rate was 81 per cent and after 18 months 75 per cent; for patients receiving coumarin treatment, the respective figures were 90 and 82 per cent and for those with no anticoagulant treatment 72 and 67 per cent, the decrease being significant. When the bypass operation was performed for limb salvage (clinical stages III and IV) the overall results were worse (12 months, 72 per cent; 18 months, 68 per cent) than in stage II and stage II-III (12 months, 90 per cent; 18 months, 85 per cent). In limb salvage surgery the positive effects of anticoagulant treatment were significant (with treatment: 12 months, 87 per cent; 18 months, 87 per cent; without treatment: 12 months, 60 per cent; 18 months, 53 per cent). The site of the distal anastomosis (above knee: 12 months, 81 per cent; 18 months, 73 per cent versus below knee: 12 months, 80 per cent; 18 months, 75 per cent) did not have any demonstrable influence on the patency rate.

Aged↗

Irradiation-induced changes in the subclavian and axillary arteries after radiotherapy for carcinoma of the breast.

Three case reports are reviewed to illustrate the possibility of treating irradiation-induced lesions of the subclavian-brachial vascular segment (aneurysm and segmental occlusions) 14, 20, and 26 years after radical mastectomy and subsequent radiotherapy. All patients had an extraanatomic vein bypass graft from the carotid to the brachial artery crossing the shoulder near the acromioclavicular joint, with the advantage that the tissue changed by radiotherapy or infected by ulceration could be circumvented. There were no postoperative complications, with adequate function of the grafts (follow-up, 17, 24, and 20 months, respectively).

Aged↗

[Regional results of human liver transplantation in Vienna].

21 cases of transplantation of the liver are analysed for indication, anaesthesia, operative management, anhepatic period, immunological therapy and specific post-operative problems (jaundice and rejection episodes). Causes of death are noted and prediction of survival gives a rate of 55%/1st year in the 17 patients operated on since 1982 under a standardised management schedule. The transplantation programme in Vienna provides routine treatment for otherwise untreatable primary (57% cases) and secondary metastatic (14%) tumours of the liver, and, in the second place, for end-stage hepatic cirrhosis (14%) and certain rare liver diseases (14%).

Adult↗

[The PTFE plastic prosthesis as an arterial replacement: experiences over a 5-year period].

Unilateral iliac femoral reconstructions with PTFE are yielding good results-similar to those with Dacron, with patency rates of 75, 67, and 65% at 1, 2 and 3 years, respectively (Kaplan-Meier). PTFE has additional advantages compared with other materials: a) no need of preclotting; b) smooth inner surface-easy thrombectomy in case of thrombosis and c) good handling characteristics. In view of the above-mentioned facts PTFE can be recommended without restriction for unilateral pelvic reconstructions. The functional early results of bilateral aorto-femoral Goretex-Y bifurcation grafts in 50 cases after 2 years are encouraging. Long-term results are still pending. Reports of other groups using this material as aorto-bifemoral substitute are not yet available. The functional results with PTFE for femoro-popliteal grafts are not satisfactory: 35% after 2.5 years. Extra-anatomical bypasses yielded 70% one-year functioning rate. Especially the ring-or spiral-armoured PTFE grafts seem to be suitable for these reconstruction procedures.

Aged↗