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S J Burnham

Publications and source records attributed to S J Burnham.

At least 37 records · Page 2Linked to original sources
PubMed1986

Quantitative analysis of continuous-wave Doppler spectral broadening for the diagnosis of carotid disease: results of a multicenter study.

This article reports the results of a multicenter study that compares 333 frequency analysis studies with the continuous-wave Doppler method with angiography. With receiver operating characteristic curves, the study documents the accuracy of the Doppler technique for the diagnosis of extracranial carotid arterial stenosis greater than 45% diameter reduction. It confirms the accuracy of the measurement of the maximal peak Doppler frequency and, in addition, shows that quantitative analysis of the instantaneous Doppler spectrum at peak systole by the measurement of the spectral broadening index is of diagnostic value. Likelihood ratios have been calculated with the use of curve-fitting techniques and it has been demonstrated how both the peak frequency and the spectral broadening index can be used together to improve the certainty of diagnosis. It is concluded that the probability that an individual patient has significant carotid arterial disease can be determined with the measurements of peak frequency and spectral broadening index from the continuous-wave Doppler spectral waveform.

Carotid Arteries↗
PubMed1986

Lower extremity amputation: the control series.

Although various techniques to determine amputation level have become available, obvious clinical factors may yet identify patients in whom a major amputation is unlikely to heal. We have analyzed the association of multiple clinical factors with the morbidity of 1028 consecutive amputations performed in 786 patients during a 13-year period. The overall operative mortality rate was 7% (57 of 786 patients). Cardiac complications were the leading cause of death (43%). In the 729 patients surviving operation, 345 above-knee amputations (AKAs) and 626 below-knee amputations (BKAs) were performed. After operation, 15.4% of these amputations failed to heal and required proximal revision. The AKA failure rate was 9% and the BKA failure rate was 19%. Significantly higher failure rates were noted in whites, nondiabetics, and those patients with heart disease. It is concluded that major amputation continues to be associated with significant morbidity and mortality rates despite changes in perioperative care and surgical technique. Common clinical characteristics indicate high-risk patients in whom a BKA is unlikely to heal and who may benefit from prospective attempts to determine amputation level.

Amputation, Surgical↗
PubMed1985

Aneurysms of the abdominal aorta. Incidence in blacks and whites in North Carolina.

We examined race and sex relative to the unexpected finding of an abdominal aortic aneurysm (AAA) at 1,665 autopsies plus 545 abdominal computed tomographic scans in subjects over the age of 50 years. We compared our demographic data with those of North Carolina and our hospital to determine if the data base was representative. White males had a higher incidence (4.2%) of AAA than any other group of race and sex (1.2% to 1.6%) or combination of groups. Although whites (2.9%) had a higher incidence than blacks (1.5%) and males (3.4%) had a higher incidence than females (1.3%), this can be attributed to the influence of the white male. The demographic data of the group studied were similar to those of our institution's admissions and to the North Carolina population. We conclude that (1) there is an increased incidence of AAA in the white male compared with the white female, black male, and black female in North Carolina; (2) there is no difference in the incidence of AAA in the white female, black male, and black female; (3) race alone may not influence the incidence of AAA as there was no difference between white and black females.

Age Factors↗
PubMed1985

Dry ice cryoamputation: a twelve-year experience.

Amputation done on an emergency basis of severely ischemic or infected limbs in critically ill patients frequently results in increased morbidity and mortality. To evaluate the effect of delaying an inevitable operative amputation by a simplified method of freezing the involved extremity, the records of 56 patients who underwent preoperative cryoamputation during a 12-year period were reviewed. Data concerning risk factors, associated medical conditions, local or systemic signs of sepsis, level of amputation, morbidity, and mortality were analyzed. Following cryoamputation of 57 limbs, 16 above-knee amputations (AKA) and 41 below-knee amputations (BKA) were performed. The overall mortality rate associated with cryoamputation was 14% (8 of 57); four postoperative deaths occurred in both the AKA and BKA groups. The mortality rate for 1021 primary operative major amputations during the same period was 7% (p less than 0.04). The only factor identified that significantly affected survival following cryoamputation was diabetes mellitus, which was present in 68% of surviving patients and in 12% of those who died (p less than 0.001). This experience suggests that cryoamputation is a valuable, simple technique that allows for deliberate stabilization and preparation of seriously ill, septic patients prior to surgical procedures, which, when performed on an emergency basis have been associated with mortality rates exceeding 40%.

Adult↗
PubMed1984

Second leg ischemia. Lower extremity bypass versus amputation in patients with contralateral lower extremity amputation.

Unilateral amputees with second leg ischemia may miss consideration for anything but amputation. Justification for a reconstructive approach for these ischemic second limbs was sought from a retrospective study of 108 patients who underwent lower extremity distal bypass. Risk factors and results were compared for the 12 unilateral amputees and the 96 nonamputees. Age and relative incidence of rest pain, claudication, and tissue loss were not significantly different for the two groups. Diabetes mellitus was present in 41.6 per cent of amputees and 31.3 per cent of nonamputees. Preoperative, average ankle-brachial blood pressure ratios were equal for both groups (0.3). Angiography showed comparable distribution of patients between the two groups with regard to distal run-off vessels. Operative mortality was 8 per cent for amputees and 3 per cent for nonamputees. Cumulative survival at 25 months was 67.5 per cent for amputees and 82.4 per cent for nonamputees. Cumulative patency at 6 months was 71.5 per cent for amputees compared with 63 per cent for nonamputees and at 25 months was 58.5 per cent for amputees and 37.6 per cent for nonamputees (no significant difference). Unilateral amputees appear to have similar risks and results for lower extremity distal bypass as do nonamputees. An independent, aggressive approach for evaluation and surgical revascularization should not be overlooked for the ischemic, remaining lower extremity in the dysvascular unilateral amputee.

Amputation, Surgical↗
PubMed1983

A passive system using rifampin to create an infection-resistant vascular prosthesis.

Vascular prosthesis infection is a devastating complication of vascular operations. The development of a simple process for imparting infection resistance to vascular prosthesis material would be invaluable. Rifampin was added to the blood that was used to preclot 8 mm Dacron vascular prostheses that were used to replace the infrarenal aorta in 10 mongrel dogs. Rings of the grafts were resected after blood had flowed through them for 0 minute, 15 minutes, 60 minutes, and 24 hours. The resected graft rings were placed on culture plates that had been inoculated heavily with Staphylococcus aureus. The rate of antibiotic dialysis from the graft was determined by comparison of the inhibition rings that were produced by the graft rings at each subsequent interval. At 60 minutes, inhibition was 94% of that at time 0. Inhibition at 24 hours was 91%, which demonstrated no significant decrease from 60 minutes. Other antibiotics were screened by this technique, but none of them demonstrated inhibition at 24 hours. In a pilot study in which two dogs were given parenteral rifampin before and after operation and grafts were preclotted with blood that contained rifampin, it was suggested that there was a slight increase in inhibition at 24 hours (93%). The data indicated that rifampin that is added to the blood that is used to preclot a porous Dacron prosthesis is so slowly dialyzed from the graft that inhibition remains at 24 hours. This passive system imparts potential resistance to the prosthesis.

Animals↗
PubMed1982

Mortality risks for survivors of vascular reconstructive procedures.

Aneurysmal disease and occlusive disease may imply different risks of hastened death. In our opinion the aortoiliac site is more favorable than the femoropopliteal site in regard to the patient's age at operation and long-term survival. A follow-up study was done of 320 patients who survived aortic aneurysm repair, 212 patients who survived aortic bypass procedures, and 203 who survived femoropopliteal bypass procedures. The median ages at the time of operation were 66, 57, and 62 years, respectively. Median years of survival for the three groups were 5.8, 10.7, and 7.2 years, respectively. The difference for survival between patients with aortoiliac occlusive disease versus those with aneurysmal disease was statistically significant, as was the difference between occlusive disease in the aortoiliac segment versus the femoropopliteal segment. The difference in median survival of patients with aortic aneurysmal disease versus those with femoropopliteal disease was not significant. White men constituted the largest group of patients. When the median years of survival for different operations in white men were stratified into 5-year age groups according to age at operation, there was no significant difference between any operations within any of the age groups. (The older subgroups were too small for meaningful analysis). This suggests that the longer median survival for aortoiliac occlusive disease can be explained by the apparently younger median age at the time of operation.

Adult↗
PubMed1980

Ankle pressure changes in distal bypass grafts during knee flexion.

Systolic ankle blood pressure was measured with the limb extended and then acutely flexed in four study groups. These included 11 normal individuals, 11 patients with below-knee autologous saphenous vein bypass grafts, 11 patients with polytetrafluoroethylene (PTFE) prosthetic below-knee bypass grafts, and 11 patients with femoropopliteal arterial occclusion who had not undergone bypass grafting. This study shows that normal limbs, limbs with saphenous vein bypass grafts, arteriosclerotic limbs, and those with PTFE bypass grafts all tolerate acute knee flexion without significant decrease in distal blood pressure.

Adult↗
PubMed1979

Summary of cases of adventitial cystic disease of the popliteal artery.

Adventitial cystic disease of the popliteal artery is explored. The results of correspondence with authors reporting this condition are elaborated upon. This has provided an opportunity to discuss the history of the condition, the findings in 115 cases which have come to the attention of the Correspondence Office dealing with this entity, and the results of treatment. A discussion of the suspected etiology of the condition is presented. The condition remains one of unknown etiology which can be treated by cyst evacuation or aspiration when the popliteal artery is patent and which is best treated by arterial reconstruction when the artery is occluded. The results of such treatment are good but are dependent upon technical excellence of the operative procedure.

Adolescent↗
PubMed1978

Vascular-laboratory diagnosis of clinically suspected acute deep-vein thrombosis.

Doppler ultrasound, impedance plethysmography, and contrast venography were performed in 207 lower limbs suspected of harbouring deep-venous thrombosis, to clarify the diagnostic value and limitations of the non-invasive methods. Doppler ultrasound and impedance plethysmography were accurate in 96% and 95% of normal limbs, respectively. In limbs with venographic evidence of thrombosis requiring treatment, Dopper ultrasound and impedance plethysmography correctly detected thrombosis in 60% and 97%, respectively. Doppler ultrasound was 97% accurate in recognising chronic venous insufficiency. Impedance plethysmography was incorrectly positive in 74% of limbs with chronic venous insufficienv cy which had no venographically detected thrombosis. These findings suggest that, for the accurate diagnosis of clinically suspected deep-vein thrombosis, venography is necessary only in patients with chronic venous insufficiency who have normal Doppler ultrasound tests and abnormal impedance plethysmograms and in patients with abnormal cardiac haemodynamics. In this series, 86% of limbs would have been spared venography had non-invasive tests been used. Venography, however, remains the standard test for the detection of minor calf-vein thrombosis. A diagnostic and therapeutic schema is proposed.

Chronic Disease↗
PubMed1978

Hemodynamic and angiographic guidelines in selection of patients for femorofemoral bypass.

Although crossover femorofemoral grafts have had good long-term patency, all patients have not been symptomatically improved. Seventy-one patients underwent 80 femorofemoral bypasses from 1968 to 1978. Hemodynamic assessment included preoperative and postoperative segmental Doppler pressures and femoral artery waveform recordings. Preoperative and selective postoperative arteriography was routinely performed. Twenty-nine failures occurred predominantely in two groups, those with greater than 50% stenosis of the donor iliac artery and those with severe recipient limb outflow occlusive disease. Ten patients with normal outflow beds bilaterally associated with 10% to 50% stenosis of the donor iliac artery underwent successful femorofemoral reconstruction. Progression of donor iliac artery disease was seen in only two patients. Cumulative five-year patency was 74%. Operative mortality totaled three (3.8%). This study supports the use of femorofemoral bypass as a primary procedure when proper guidelines are used.

Adult↗
PubMed1978

Penile blood pressure in the evaluation of erectile impotence.

Identification of specific etiologies of erectile impotence is hindered by a paucity of objective criteria needed to segregate organic from psychogenic varieties and to define specific organic causes. Simplified measurement of penile blood pressure was performed with a digital cuff and a portable ultrasound Doppler system for flow detection. An index relating penile-to-brachial systolic blood pressure was generated, and the results were compared in patients with impotence versus patients with normal erections. The mean indices for the two groups were significantly different (P less than 0.05). The penile-to-brachial index provides an additional diagnostic tool in the evaluation of potency, allowing us to identify those patients with decreased penile blood flow, and may be helpful in selecting patients for revascularization procedures.

Blood Pressure↗
PubMed1978

Carotid endarterectomy: a follow-up study of the contralateral non-operated carotid artery.

In a study of 103 patients surviving carotid endarterectomy, follow-up information was obtained from all patients over a period of time extending to four years. This was done so that better decisions could be made regarding recommendations for contralateral carotid surgery. In this follow-up study, only three patients had contralateral surgery. Three additional patients had events clearly in the territory supplied by the contralateral carotid artery, and no patient suffered a contralateral stroke. There were an additional four patients who suffered stroke in territory not supplied by the contralateral carotid artery. In addition, four patients experienced classical transient ischemic episodes referrable to the operated carotid artery and ten patients experienced nonclassical cerebral ischemia. Seven of the 103 patients died at times remote from the carotid surgery of nonstroke cause.

Aged↗