PubMed Health⌕ Search

Biomedical subjects

I M Ibrahim

Publications and source records attributed to I M Ibrahim.

At least 55 records · Page 3Linked to original sources
PubMed1980

Adjunctive arteriovenous fistula with tibial and peroneal reconstruction for limb salvage.

Arteriovenous fistulas were constructed as an adjunct to femoral peroneal and tibial bypasses in 13 patients threatened by imminent limb amputation. Previous attempts at conventional vascular reconstructive procedures had failed in nine patients. Deficient or absent pedal arches were noted in all patients, as were poor quality or small crural arteries. Graft patency was achieved in 11 cases and limb salvage in 10. There was no mortality. A steal phenomenon occurred in one patient and was successfully treated by secondary popliteal vein ligation. These preliminary results clearly indicate that an adjunctive arteriovenous fistula can maintain patency in a femoral tibial or peroneal bypass graft while preserving flow into the markedly diseased distal circulation.

Aged↗
PubMed1980

Remote profunda femoral bypass for limb salvage.

Patients with patency of the distal segment of the profunda femoral arteries can be subjected to a direct end-to-side bypass with either tissue or synthetic grafts to increase blood flow to the lower extremity. The effectiveness and durability of this procedure will be enhanced by patency of the popliteal artery. Diffuse profunda femoris disease, popliteal or tibial peroneal obliterative disease and gangrenous lesions tend to militate against the success of this operation as an isolated procedure without augmenting flow to the distal part of an artery in the leg. Of 18 remote profunda femoris bypasses performed during a four year period, early amputation was required in two patients because of inadequate distal flow and the inability to establish downstream reconstruction. In one patient, an early bypass to the peroneal artery was required following closure of the profunda femoris bypass. The remaining 15 bypasses resulted in limb salvage and significant relief of symptoms. Three patients subsequently required secondary downstream reconstructions. The profunda femoris is surgically accessible for a long length and can serve as an adequate source of blood to the leg and foot in selected patients.

Aged↗
PubMed1979

The role of the peroneal artery for limb salvage.

Peroneal artery revascularization was performed in 61 cases for limb salvage and compared to a comparable group of 89 tibial artery reconstructions. Preoperative arteriography is essential to define runoff quality and pedal arch integrity. Intraoperative arteriography and flow determinations minimize failures due to technical error and provide some indication of the prognosis for graft patency. Failure to augment flow by at least 50% suggests pedal arch deficiency and is predictive for early graft closure. Cumulative patency for peroneal bypass was 55 +/- 8% at 1 year and 38 +/- 10% at 30 months compared to 63 +/- 6 and 59 +/- 7% for tibial reconstructions at the same time intervals. Most graft failures occurred within the first six months. Nineteen peroneals have been followed for more than one year with only three failures occurring. Improved criteria for case selection resulted in an 80% decrease in the number of failed grafts for the second half of this series. A similar reduction was noted for secondary operations. Results obtained with good quality saphenous veins (37 +/- 13% at 30 months) and glutaraldehyde tanned umbilical veins (53 +/- 11%) depend more on technical, pathologic and biologic factors than on the particular graft material employed. The mortality rate at 30 days was 3.3% and compared favorably with other limb salvage procedures and with primary amputations. Cumulative patient survival with functional limbs was 79 +/- 9% at 30 months and was distinctly superior to reported data on survival of amputees. A cumulative limb salvage rate of 79 +/- 6% at 30 months for the peroneal group makes such reconstructions definitely favorable to uniform limb ablation.

Amputation, Surgical↗
PubMed1979

Synchronous aortofemoral or iliofemoral bypass with revascularization of the lower extremity.

Bypassing aortoiliac stenosing lesions to the profunda femoria alone, even with extensive end-arterectomy and angioplasty of the latter, will not provide predictable excellent results in the presence of gangrene and occlusion in the femoral popliteal system. With severe pregangrene and rest pain, residual ischemic complaints are also common, and if lesions are present, healing is incomplete or, at best, delayed. Alternatively, femoropopliteal or tibial bypass, in the presence of even moderately diminished inflow, is subject to either early or delayed closure, unless proximal repair is also performed in appropriately selected patients. Synchronous correction of tandem lesions involving the aortoiliac and femoropopliteal segments should, therefore, be considered for limb salvage only and particularly in the presence of focal gangrene, excision or debridement of which can be anticipated to heal after successful bypass. Major diminution in femoral inflow usually indicates the need for proximal repair only, even in the presence of distal lesions. Noninvasive studies and intraoperative flow determinations are not uniformly helpful in patient selection. Synchronous aortofemoral or iliofemoral and femoropopliteal or tibial reconstructions were performed upon 38 patients, 15 of whom had no prior vascular operation and 23 of whom had previously undergone either aortofemoral or femoropopliteal bypasses that had failed. Graft patency for all patients was 76 per cent, and although it was better for the patients in group 1 than for those in group 2, no statistical significance existed between the two groups. Improved patient selection and criteria for performing synchronous reconstructions might originally have been of benefit for the patients in group 2, avoiding more difficult secondary repairs. It must be emphasized, however, that synchronous reconstructions should not be done routinely in the presence of multilevel disease. Rather, specific indications do exist and should be considered on an individual basis.

Aged↗
PubMed1978

Evaluation of glutaraldehyde-tanned human umbilical cord vein as a vascular prosthesis for bypass to the popliteal, tibial, and peroneal arteries.

One hundred and thirty-one reconstructions to the popliteal (n = 80), tibial (n = 26), and peroneal (n = 25) arteries were performed using glutaraldehyde (GA)-tanned human umbilical cord veins. Cumulative patency rates to 20 months, calculated by the standard life-table method were 84.8%, 74.0%, and 49.6% for popliteal, tibial, and peroneal reconstructions, respectively. The latter included many of the early cases with extremely advanced obliterative atherosclerosis and gangrene. These results are equivalent and even superior to those obtained with saphenous veins, particularly when the cases are analyzed in distinct clinical and pathological categories. The quality of the runoff was the major determinant in obtaining long-term patency and limb function. The primary factor accounting for graft closure was progression of the atherosclerotic process in the distal circulation. No failures could be attributed directly to the graft. This clinical experience confirmed previous data showing the unique properties of the GA-tanned umbilical vein. It is anticipated that longer-term follow-up will continue to show the superior qualities of this new vascular substitute.

Aged↗
PubMed1978

Evaluation of intraoperative arteriography as a routine for vascular reconstructions.

A retrospective analysis of 391 intraoperative arteriograms performed after reconstruction operations on the carotid, aorta and lower extremity vasculature showed the value of incorporating this procedure as a routine only for the last mentioned site. Identification and correction of inadequacies due to technique are possible. Revisions in technique based upon these experiences have significantly diminished their incidence. Routine intraoperative arteriography for revascularization procedures of the lower extremity has further enabled us to classify reliably the runoff and correlate these findings with subsequent graft patency. Late graft closure, predominantly due to progressive or accelerated obliterating atherosclerosis in the distal circulation, occurred almost exclusively within the first year following reconstruction in those patients identified as having poor runoff by intraoperative arteriography. This group, in particular, should be closely monitored by noninvasive physiologic means and even post-operative arteriography to enable either prophylactic or therapeutic correction. In some instances, based upon intraoperative arteriography or subsequent studies, fruitless and potentially harmful reoperative vascular procedures may be obviated.

Angiography↗
PubMed1977

A simple guideline to facilitate axial alignment of vascular grafts.

The proper orientation of vascular prostheses is essential for successful performance of vascular reconstructions. To prevent axial rotation of grafts, particularly in long tunnels such as in the axillo-femoral or subsartorial position, vascular prostheses with a simple guideline incorporated within their fibers were employed. The advantages of these grafts are discussed.

Aorta, Abdominal↗
PubMed1976

Human umbilical cord. A new source for vascular prosthesis.

Reconstructions were performed to the popliteal, tibial, and peroneal arteries employing a modified umbilical cord vein prosthesis. The latter was obtained from human cords and was made available as an onshelf graft for surgery following glutaraldehyde tanning. The early patency and limb salvage rates are equivalent to those obtained with autogenous saphenous veins. Additional benefits include significant decreased operative time and morbidity. It is also probable that this new graft may be resistant to biodegradation and therefore may obviate many of the causes for late failure that occur with the use of living biologic tissues or collagen tubes. Long-term follow-up and study are essential to validate the results obtained thus far and to assess the potential of this new graft in a variety of vascular reconstructions.

Aged↗
PubMed1976

Arteriovenous fistulas constructed with modified human umbilical cord vein graft.

Arteriovenous (AV) shunts were created using modified umbilical veins in baboons. The shunts consisted of veins removed from human umbilical cords tanned by either dialdehyde starch or glutaraldehyde 2% and surrounded with a polyester fiber mesh. Twelve fistulas were constructed employing the femoral or axillobrachial vessels. Six of the seven straight axillobrachial shunts remained patent for up to four months during the period of study. One of two loop fistulas and three femoral AV fistulas thrombosed because of kinking. There were no infections, mural disruptions, or aneurysm formations. Anglogram results and histologic studies confirmed the maintenance of graft function, morphologic appearance, and tolerance to repetitive punctures.

Animals↗
PubMed1976

Lumbar sympathectomy in end stage arterial occlusive disease.

Sixty-one patients had lumbar sympathectomies performed for end stage occlusive vascular disease manifested by gangrene of less than one-half of the foot, ulcerating ischemic lesions, rest pain or rapidly progressive markedly limiting intermittent claudication. The operative procedure was standardized to permit removal of the lowermost preganglionic fiber at the level of the crus of the diaphragm and the ganglionated chain to the crossing of the iliac vessels. The immediate postoperative mortality was 6.5% from cardiac causes. Over all improvement rate was 60% while early amputation rate was 40% for the entire group. Those patients with rest pain had the poorest prognosis with an amputation rate of 53%. The results are compared to other groups and factors of patient selection, anatomy of the sympathetic chain in relation to operative technique, physiology of decentralization versus devervation are discussed. The procedure is worthwhile in patients who are not candidates for arterial reconstruction who are faced with the prospect of early amputation.

Amputation, Surgical↗
PubMed1976

Clinical experience with modified human umbilical cord vein for arterial bypass.

Umbilical veins were removed from human cords, tanned with gluteraldehyde, and surrounded by a polyester fiber mesh. Arterial bypasses were performed with this material in eight persons with threatened limb loss and for whom no other graft material was available. The distal anastomoses were to the small vessels of the leg or to the popliteal artery below the knee. Limb salvage and function were obtained in five patients. Three of these also required early thrombectomy to obtain success. This complication may be related to the presence of gluteraldehyde oligomers and polymers of free aldehyde groups. Morphologic evaluation of the graft suggests that human umbilical cords are a potentially valuable source for vascular substitutes.

Aged↗
PubMed1976

Revascularization of the peroneal artery.

In the absence of a suitable popliteal or tibial arterial system with direct communication to a pedal arch, the peroneal artery may be used for distal anastomosis with the expectation of achieving patency rates exceeding 60 per cent. Morbidity can be minimized by careful patient selection and by imporved surgical technique and materials. In 14 of 23 peroneal bypasses, patency was maintained compared with 27 to 35 bypasses to the tibial artery system. Limb salvage was 57 per cent for th peroneal artery group compared with 71 per cent for tibial artery reconstruction.

Arteries↗