Biomedical subjects
Publications and source records attributed to G Kretschmer.
A serious complication associated with vascular surgery is active or potential hemorrhage due to infected pseudoaneurysm. In two cases of false aneurysm, embolization with the Gianturco-Anderson-Wallace (GAW) coils was performed and blood supply was preserved by autologous vascular grafts, thereby emphasizing the feasibility of a combined approach in patient management.
Our results seem to demonstrate that, even when healthy or arteriosclerotic arteries tolerate knee flexion without any impairment of blood flow, all bypass materials, to a certain extent, have a tendency toward morphologic changes, such as kinking, looping, stenosis and decrease of peripheral blood flow. Reocclusion in below-knee reconstruction, which cannot be explained by poor outflow situation or technical faults, might be related to the graft material used as well as hemodynamic changes caused by flexion of the knee joint. With the use of ASV grafts, these changes are minimal and of little or no clinical importance; when HUV is used, these changes are more distinctive and might, in some instances, be the cause of reocclusion. This could explain the difference in the late results with the use of ASV or HUV. The results of reinforced PTFE still await evaluation. However, it should be kept in mind that the results in addition to the already mentioned influences are also caused by neointima proliferation and progression of the disease.
During the past 2 years (April 1981-March 1983) 50 PTFE Y-grafts were implanted. The early results are good. Except one graft limb occlusion (8 months postoperatively), which was successfully managed by thrombectomy, all grafts are functioning well or did so until death. 5 patients (age 70-84 years, aortic aneurysm, additional vascular surgery) died 1 day to 8 weeks postoperatively. The death was not specifically related to the material of the new prosthesis. Advantages of PTFE are: a) no need of preclotting; b) absolute tight body of the prosthesis even in the heparinized patient; c) thrombectomy is easy to perform. Important technical details, mandatory for a safe operative procedure and for good functional as well as morphological results, are reported.
Explore the source record for details and available documents.
Employing an extrathoracic approach 10 patients were operated upon for 12 obstructive lesions of the subclavian arteries using carotid-subclavian anastomosis. The operation was indicated 3 times for the pathological entity of arterial stenosis embolizing into the vascular periphery, 3 times for claudication of the upper extremity and 4 times for cerebro-vascular insufficiency. Followed up to 31 months all anastomoses remained patent. All the complications were managed conservatively and were considered of minor importance.
Description of 8 patients, demonstrating deep infections following vascular reconstructive procedures. The classical method of treating these consists of removing all foreign material and circumventing the lesion by extra-anatomic bypass. A long extra-anatomic conduit needs a good run-off, therefore alternative methods of treatment are sometimes indicated, e.g. transposition of the omentum. In 8 instances healthy omentum was used to cover the infected conduit in order to preserve the reconstruction and to obtain healing of the wound. The procedure was successfully employed in 4 cases. Solitary infections healed without complications (3 patients). Out of 5 patients showing the catastrophic sequence of events - infection plus exsanguinating hemorrhage - only one was managed successfully.
In a high risk patient an extended extraanatomic PTFE (ring armored) bypass was performed for limb salvage. The right subclavian artery served as donor vessel to the left tibial anterior artery in a crossover suprapubic fashion. A total of 7 anastomoses in this subclavian bifemoro-crossover popliteo-crural reconstruction yielded a high flow situation as well as good function with a palpable dorsalis pedis artery pulse and a postoperatively increased ankle-brachial pressure index of 0.9, 8 months postoperatively. During the 9th postoperative month the distal part of the reconstruction occluded and the left leg was amputated below the knee. However, limb salvage was achieved for 9 months. Several points are discussed in connection with long-term functioning.
Explore the source record for details and available documents.
The case is reported of a 35-year-old man who had been treated with hemodialysis for five years because of renal insufficiency due to chronic glomerulonephritis. Renal cystic disease acquired during maintenance dialysis was complicated by bilateral kidney rupture within an interval of two months. Development of cystic changes of kidneys during long-term hemodialysis was first reported in 1977. The main complications of this cystic transformation are, according to the literature, development of neoplasms and hemorrhage into the cysts. In the present case the clinical symptomatology consisted of episodes of severe pain in the flank, hematuria, hypotension and lowering of hematocrit. An ultrasound study demonstrated enlargement of some cysts compared to another study some months ago, and internal echoes due to hemorrhage could be seen in some of the cysts. Because of the danger of spontaneous kidney rupture with consecutive life-threatening hemorrhage, surgery is indicated in such cases.
Explore the source record for details and available documents.
37 renal allografts were performed on 27 children of 2-16 years of age. In 67% function was maintained for more than a year. At the beginning of 1981, 13 children had functioning grafts with a median serum-creatinine level of 1.8 +/- 1.2 mg%. 4 children had a functioning graft for more than 7 years. All children with functioning grafts were fully rehabilitated. Hence, renal transplantation is the optimal therapy in chronic renal insufficiency in childhood.
Explore the source record for details and available documents.
21 patients had aortoiliac reconstructions for aortic aneurysms or occlusive disease with the new PTFE Y-graft during the past 12 months. 2 patients in the aneurysm group with additional renal artery reconstruction suffered postoperative myocardial infarction and subsequently died. 2 patients older than 80 years died after aneurysm repair in cause of graft infection, respectively respiratory insufficiency. All grafts (n=17) are functioning well or did so until death of the patient (n=4). The obvious advantage of the PTFE Y-graft is the fact, that there is no need of preclotting. Suture line--even using 4-0 material at the proximal anastomosis--and graft body is absolutely tight and no blood loss has to be expected from this site. However positioning of the left limb of the y-graft can be difficult in patients with right sided extraperitoneal approach and proximal side end anastomosis. Performing an end-end anastomosis can overcome this problem. For occlusion of the prosthesis limbs two vascular clamps on each side are needed to control blood flow within the rather stiff graft. Immediate and short term function is excellent. There was no material specific complication noted until now. Further longterm experience is necessary to evaluate the definitive quality of this new prosthetic material after some years.
Five cases are reported with the pathological entity of proximal arterial stenosis and embolization into the peripheral vascular bed. Therapeutic management, e.g. diagnostic work-up, eradication of the embolic source and embolectomy of the peripheral arterial tree - if technically feasible - seems beyond any doubt. Sometimes the diagnosis is difficult to obtain, since in the upper extremity microembolic seeds occur, posing a differential diagnosis problem. Once a partial sternotomy and in situ removal of the lesion was employed, in the remaining cases extrathoracic repair was done. In the left subclavian artery using a carotid-subclavian-anastomosis, we obtained satisfactory results, in the right subclavian and end-to-end-anastomosis was performed after resection of the diseased arterial segment.
128 Patients were operated upon consecutively since 1965 for lesions of the carotid bulb (stadium I.: n = 21;stadium II: n = 45;stadium III: n = 33; stadium IV:n - 29), a postoperative neurological deficit was noted in 4,7%, the cerebral lethality was 1,9%. The procedure was done in general anesthesia with moderate elevation of the systemic blood pressure. In case the pressure readings obtained in the stump of the internal carotid artery were below the level of 50 mm of mercury an intraluminal shunt was used. Considered an average lethality of 7% per year 48 patients died during follow-up, 5 for cerebral. 10 for internal medical reasons, in 33 cases the results of post mortem examination was not available. After a mean follow-up time of 7 years 41 patients were re-evaluated 4,8 recurrent stenoses, 2,4% intracranial and 9,4% changes in the contralateral carotid artery were detected. Only 4,8% showed abnormalities on neurological examination, which underscores the importance of non invasive diagnostic tools.
Explore the source record for details and available documents.
65 consecutive renal artery stenosis reconstructions for the treatment of severe renovascular hypertension are reported. 63% of the cases were males, 37% females. The disease was caused by arteriosclerosis in 66% of cases and in 23% by fibromuscular dysplasia or other pathological changes of the renal artery; the mean age was 47 in the former. and 31 years in the latter group. An aortorenal saphenous vein bypass was performed in 35% cases, a dacron graft was used in 29% and thrombendarteriectomy was carried out in 23% cases. Positive results were achieved in 68.8% of the patients. 63% of the females became normotensive. Operative mortality due to faulty technique was 4.9% initially. The operative mortality has been zero since 1973. nor have there been any therapeutic failures on a technical basis. No significant correlation was established between age of the patients and result of operation.
The intraoperative angiography was employed in 307 vascular reconstructive procedures (thrombendarterectomies (TEA) n = 107 = 34.8%; Veinbypass (VBP) n = 145 = 47.2%; fabric grafts (KBP) n = 44 = 14.4%) within the femoro-popliteal and crural region. 11.7% unsuspected technical errors were detected (TEA 18.6%, VBP 8.2%; KBP:6.8%) by angiography and successfully revised prior to wound closure. Errors were most common after thrombendarterectomies followed by VBP and KBP. Revisions after immediate failures were performed successfully in 7.4% (TEA : 8.4%, VBP: 5.5%, KBP: 6.8%). Lesions on X-ray of questionable significance were accepted in 6.8%, and followed by 4 immediate occlusions (1.7%). In 3.6% of the angiogramms the film was not satisfactorily exposed from the technical point of view. We think intraoperative angiography is a valuable adjunct in peripheral vascular surgery helping to detect and correct technical errors.