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Biomedical subjects

D Bergqvist

Publications and source records attributed to D Bergqvist.

At least 163 records · Page 9Linked to original sources
PubMed1996

Incidence and clinical presentation of bowel ischaemia after aortoiliac surgery--2930 operations from a population-based registry in Sweden.

OBJECTIVES: To study the incidence and clinical presentation of intestinal ischaemia after aortoiliac/femoral surgery, and to validate a vascular registry concerning a serious complication. DESIGN AND SETTING: In the Swedish Vascular Registry (SWEDVASC) the outcome and complications of all vascular procedures are registered prospectively. MATERIALS AND METHODS: All 2930 patients operated in 1987-93 were analysed for notified complications. A 5% random sample of all patients and a 20% random sample of fatal cases were analysed for un-notified complications. Of 415 requested patient records 413 were analysed. RESULTS: The estimated incidence of bowel ischaemia was 2.8%. Among patients operated on for a ruptured aneurysm in shock it was 7.3%. Of the 63 patients with intestinal ischaemia only 15 presented with early passage of bloody stools. In 60 patients (95%) the lesion affected the left colon within the reach of a sigmoidoscope. Bowel ischemia was unnotified only in fatal cases, the estimated un-notified complication rate was 0.7%. CONCLUSIONS: The incidence in this study on unselected patients did not differ from previous reports from specialised centres. Diagnosis is difficult and justifies a high index of suspicion and early use of sigmoidoscopy. The validity of the SWEDVASC registry was confirmed by a high report-rate for this complication.

Aged↗
PubMed1996

Regional differences in mechanical properties between major arteries--an experimental study in sheep.

PURPOSE: To study possible differences in mechanical properties between central (abdominal aorta) and more peripheral (common carotid and common femoral) arteries validating an earlier non-invasive study in children showing that central arteries are more distensible than peripheral ones. As invasive blood pressure was needed, but ethically impossible to obtain in children in an experimental setting, an animal model was chosen. DESIGN: Open experimental study. SETTING: Animal laboratory at university hospital. MATERIAL AND METHODS: The pulsatile vessel wall movements of the abdominal aorta (AA), common femoral (CFA) and common carotid (CCA) artery of nine sheep were examined using an ultrasound phase-locked echo-tracking technique. Intra-arterial blood pressure was measured and pressure-diameter relations, pressure strain elastic modulus (Ep) and stiffness (beta) calculated. Distensibility was defined as the inverse of Ep and stiffness. RESULTS: The AA showed lower values for Ep and stiffness (beta) than the CFA (p = 0.002) and CCA (p = 0.006), i.e. the latter two vessels were stiffer. The pressure-diameter relations confirmed these differences and showed a non-linearity for all three vessels with increased stiffness above 70-90 mm Hg. CONCLUSION: This study on young animals supports earlier findings of differences in mechanical properties between central and more peripheral arteries seen in healthy children. As pathologies between these vessels differ, with dilatation of the abdominal aorta and occlusive disease in the more peripheral vessels, part of the explanation might be found in the mechanical properties of the healthy vessels, characterised here with the echo-tracking technique.

Animals↗
PubMed1996

Prognosis in elderly men with screening-detected abdominal aortic aneurysm.

OBJECTIVES: To study the natural course of screening-detected symptomless abdominal aortic aneurysm (AAA) in elderly men. SETTING: Malmö, a city in southern Sweden with 230,000 inhabitants and a single referral hospital. MATERIALS: 423 seventy-four-year-old men, randomly selected from the population and belonging to the prospective population study "Men born in 1914", were invited. 343 underwent AAA screening, whereas 80 declined or had moved. CHIEF OUTCOME MEASURES: Five year all cause mortality in relation to participation in and findings at ultrasound screening for AAA. MAIN RESULTS: An abdominal aortic aneurysm was present in 38 (11%) out of 340 men who underwent screening and who had a native aorta. During 5 years of follow-up, one third (13/38) of these men died; 7 from myocardial infarction and 3 from stroke. The mortality rate in men with AAA was 80.2/1000 person years; twice as high as it was in men without AAA (39.4/1000 person years; p = 0.018). Six men underwent AAA surgery. None of them died from aneurysm rupture. However, aneurysm surgery did not reduce the total mortality rate in these men. The highest mortality rate, 91.9/1000 person years, was found in the men who did not participate in the screening. CONCLUSIONS: It is our conclusion that screening for early detection and intervention is of questionable value from a public health perspective.

Aged↗
PubMed1996

Secondary aortoenteric fistulae--changes from 1973 to 1993.

AIM: To investigate a series of patients with secondary aortoenteric fistulas and compare it with a previous series (1985-93 vs. 1973-84). DESIGN: Retrospective study of medical records. SETTING: Sixteen vascular surgical centers in Sweden. PATIENTS: Twenty-seven patients were identified making an overall incidence of 0.5% of all aortoiliac operations. Among aneurysm patients the incidence was significantly lower than in the previous series. One patient record could not be identified. Fourteen primary operations were for aortic aneurysm, 12 for occlusive disease and one was an aortorenal vein bypass. RESULTS: Symptoms of the fistula occurred after a median interval of 90 months which is significantly later than the previous series (32 months; p<0.05). The commonest presentation was bleeding followed by septis. The median diagnostic delay was 10.5 days, which was significantly shorter than in the previous series. Most fistulas involved the duodenum (88%). One patient died before surgery. The postoperative mortality was 28%, significantly lower than in the previous series (58%) (p<0.05). At the end of follow up (median 43 months) significantly more patients were alive than in the previous series (42% vs 18%) (p<0.05). CONCLUSION: Over a 21 year period there seems to have been a decrease in the frequency of secondary aortoenteric fistulas after aneurysm surgery, a longer interval before they occur, a shorter diagnostic delay, and a better survival.

Aorta, Abdominal↗
PubMed1996

Value of duplex scanning in evaluation of crural and foot arteries in limbs with severe lower limb ischaemia--a prospective comparison with angiography.

OBJECTIVES: To compare Duplex scanning with angiography for evaluation of crural and pedal arteries in limbs with lower limb ischaemia. DESIGN: The findings obtained during Duplex scanning and angiography were prospectively compared in a blinded manner. SETTING: Departments of Surgery, Diagnostic Radiology and Clinical Physiology, University Hospital. MATERIALS: Duplex scanning and selective angiography of femoropopliteal, crural and foot arteries were performed in 40 limbs (38 patients, 480 segments) with intermittent claudication (n = 6), rest pain (n = 13) and ulcer/gangrene (n = 19). Each arterial segment were graded into four categories: normal, < or = 50% diameter reduction, > 50% diameter reduction and occlusion. Pedal arteries were evaluated as patency or occlusion of dorsal pedal artery and plantar arch. CHIEF OUTCOME MEASURES: Accuracy (AC), sensitivity (SE), specificity (SP), positive predictive (PPV), negative predictive (NPV) and kappa values. MAIN RESULTS: The Duplex scanning of the tibioperoneal trunk, crural and pedal arteries had an accuracy of 80% (kappa = 0.6). The SE, SP, PPV and NPV values were 83%, 77%, 79% and 81%, respectively. The SP was relatively low for the peroneal artery (58%) compared to the others. CONCLUSIONS: The results demonstrate the feasibility and reliability of Duplex scanning in detecting crural and pedal artery lesions in lower limbs with severe ischaemia.

Adult↗
PubMed1996

Accuracy of duplex sonography before carotid endarterectomy--a comparison with angiography.

OBJECTIVES: The aim of this prospective study was to contribute to the evaluation of the reliability of Duplex sonography (DS) before carotid endarterectomy (CEA). DESIGN: The study was performed prospectively in a university hospital setting. METHODS: Eighty-one consecutive patients aged 49-83 years were examined with DS and carotid angiography (CAG) before CEA. The results of the DS were judged as either confident, or CAG was assessed to be necessary preoperatively. The results from the DS and the CAG were then compared. RESULTS: DS was judged as confident in 148 of the 162 arteries examined. In none of these 148 arteries did CAG change patient management in any way, and the agreement between DS and CAG was good. In the remaining 14 arteries CAG was judged necessary, in 11 arteries because DS assessed the internal carotid artery (ICA) as occluded, which was confirmed by CAG in 10 arteries. In three arteries the reason was poor quality of the DS, however these three arteries were correctly assessed as severely diseased. CONCLUSIONS: This study confirms that DS alone is sufficient in the preoperative evaluation before CEA, provided that CAG is performed whenever DS shows occlusion of the ICA, or when the quality of the DS is poor.

Aged↗
PubMed1996

Composite polytetrafluroethylene/vein bypass grafts: conventional distal vein segment or vein cuff?

OBJECTIVES: To determine the current status of PTFE vein composite grafts, we reviewed our experience with 205 composite reconstructions and compared the results of conventional distal vein segment to that of distal vein cuff. DESIGN: Retrospective review. SETTING: Department of Surgery, University Hospital. PATIENTS AND METHODS: The series included 85 women and 102 men with a median age of 70. The indications for surgery were claudication in 30, rest pain in 71 and ulcer/gangrene in 103. The site of the distal anastomosis was the popliteal artery in 111 and crural artery in 94. The graft consisted of a proximal PTFE graft anastomosed to a distal segment of reversed saphenous vein in 169 or to a modified distal Miller cuff in 36 operations after 1992. RESULTS: Cumulative life table primary patency rates for the whole series at 12, 24 and 36 months were 39%, 32% and 25% respectively. Limbs with good run-off demonstrated significantly better patency rates compared to limbs with poor run-off (55% and 17% at 12 months, 35% and 11% at 36 months, p = 0.04). The patency rate of femorocrural grafts with poor run-off was only 4% at 12 months. The overall limb salvage rates at 12 and 36 months were 63% and 55%, respectively. Similar results were obtained in limbs with distal reversed vein segment and distal vein cuff. CONCLUSION: The results of this study suggest that for infrainguinal bypass grafting where the saphenous vein is unavailable, a composite PTFE-vein graft might be an acceptable alternative in limbs with good run-off. Although not a randomised study, the results using a distal reversed vein segment of a cuff were similar.

Adult↗
PubMed1996

Recovery of endothelial cells and prostanoid production in endothelial cell-seeded grafts.

OBJECTIVE: To investigate the function and morphology of endothelial cell (EC) seeded grafts. DESIGN: Experimental, open study. CHIEF OUTCOME MEASURES: Endoluminal release of prostacyclin (6-Keto-PGF1 alpha) and thromboxane B2 (TxB2), patency, EC coverage and cell identity. MATERIALS: In 12 sheep, segments of both carotid arteries were excised. On one side a seeded and on the other an unseeded dacron graft were inserted. After 3 months the grafts were excised. In grafts and arteries, the endoluminal release of 6-keto-PGF1 alpha and TxB2 was determined in a perfusion system. Scanning electron microscopy (SEM) and light microscopy were used to determine the EC coverage and cell identity. RESULTS: Eight animals survived. Three seeded and two unseeded grafts were occluded. Prostacyclin release did not differ significantly between seeded and unseeded grafts and arteries, when the arteries were looked upon as one group. When the graft was compared with its corresponding artery, i.e. the artery it replaced, a significantly lower release was found in the unseeded group. Thromboxane release was undetectable in arteries but significantly higher in both graft groups. SEM revealed a cellular coverage of 75% in the seeded grafts and 50% in the unseeded (not significant). Light microscopy showed a patchy staining for Factor VIII-related antigen in some grafts in both groups. CONCLUSION: Prostacyclin release in unseeded and seeded dacron grafts did not differ 3 months after implantation in sheep, except when the graft was compared with its corresponding artery. The significance of this remains to be settled. Seeded grafts did not have a higher proportion of endothelial coverage than unseeded grafts.

6-Ketoprostaglandin F1 alpha↗
PubMed1996

Low molecular weight heparins.

Low molecular weight heparins (LMWHs) differ from unfractionated heparin (UFH) in a number of characteristics, which is probably due to differences in molecular weight distribution. From a clinical point of view the better subcutaneous bioavailability and longer biological half-life are important, making it sufficient to inject LMWHs once-daily only. For practical purposes it is also important that LMWHs be used without monitoring. They are effective as prophylaxis against postoperative venous thromboembolism after all types of surgery; in most studies, more effective than UFH. In most studies, this effect can be obtained safely and with less bleeding than with UFH. LMWHs compare favourably with UFH for starting treatment of deep vein thrombosis, as well as an anticoagulant during haemodialysis. Adverse effects such as thrombocytopenia and osteoporosis are more common with UFH than with LMWHs. Studies evaluating whether or not LMWHs can replace UFH in arterial diseases are still few with small sample sizes. Thus further systematic research is needed.

Heparin, Low-Molecular-Weight↗
PubMed1996

In vitro attachment of endothelial cells to different graft materials.

The purpose of this study was to compare the degree of endothelial cell attachment to different synthetic vascular graft materials. Human microvessel endothelial cells were labelled with indium-111-oxine, injected into 9 different vascular grafts and left to adhere for 40 min. Unattached cells were removed and radioactivity of the grafts measured. Grafts were flushed with 20 ml phosphate-buffered saline during 5 s to remove cells with poor attachment and radioactivity was measured again. Attachment differed between the grafts. In order of decreasing attachment the grafts were albumin-coated Dacron (47%), preclotted Dacron (35-44%), gelatin-coated Dacron (20%), gelatin-coated polyurethane (17%), collagen-coated Dacron (12%), preclotted expanded polytetrafluoroethylene (ePTFE; 3%). Albumin-coated Dacron showed the highest degree of cell attachment of ePTFE the lowest. Statistically significant differences exist between ePTFE and all other grafts and between albumin-coated and collagen-coated Dacron, gelatin-coated polyurethane and gelatin-coated Dacron.

Blood Vessel Prosthesis↗
PubMed1996

Prolonged prophylaxis against postoperative venous thromboembolism.

This review deals with the problem of delayed thrombosis and thereby the potential need of prolonged prophylaxis. The risk of late thrombosis and pulmonary embolism is discussed from pathogenetic factors and data on frequencies of thromboembolic complications in the literature. The problems concerning long term or prolonged prophylaxis are indicated and studies on prolonged prophylaxis-our own included-are analyzed. There is an urgent need to define which risk factors motivate prolonging thromboprophylaxis for more than the standard 7-14 days.

Adult↗
PubMed1996

The postdischarge risk of venous thromboembolism after hip replacement. The role of prolonged prophylaxis.

This review deals with the problems of delayed thrombosis after hip arthroplasty and the possible need for prolonged prophylaxis. These problems have been considered key questions in the European Consensus Statement on venous thromboembolism. There are several factors, such as long immobilisation, venous trauma and decreased venous emptying, which all may contribute to the development of late postoperative thrombosis. There are data on frequencies of venous thromboembolism supporting the occurrence of such late complications. In 4 recent studies on prolonged prophylaxis, it was consistently shown that prophylaxis with low molecular weight heparins for 1 month significantly reduced the frequency of deep venous thrombosis compared with conventional prophylaxis during hospitalisation in patients undergoing elective hip arthroplasty.

Anticoagulants↗
PubMed1996

A modified technique of ultrasonic triplex scanning of the lower extremity arteries.

This study was undertaken to evaluate the utility of a modified technique of triplex scanning of the lower extremity arteries in 20 subjects without any clinical signs of arterial disease. The distal aorta and iliac arteries were examined with the subject in supine position and lying slightly on the opposite side. By moderate compression of the probe towards the psoas muscle and directing it over the iliac arteries with slight medial retraction of the abdomen, satisfactory visualization of the common and external arteries with 7.5 MHz high resolution imaging and a 5.6 MHz doppler probe were obtained in 56 of 80 segments (70%). In obese individuals it was necessary to use 5 MHz probe for satisfactory scanning of the aortic bifurcation and common iliac arteries. The distal superficial femoral, popliteal and tibioperoneal trunk segments were examined with the patient prone and the knee slightly flexed. Peak systolic, early diastolic reverse and late diastolic forward flow velocities were studied together with measurement of the arterial diemeters, which demonstrated wide variations. This study suggests that satisfactory scanning of the iliac and femoropopliteal arteries with the described technique can be achieved in the majority of subjects with a superficial high resolution probe. The combination of 7.5 MHz two-dimensional imaging with a 5.6 MHz pulsed wave Doppler probe offers optimal information of these arteries in nonobese individuals.

Adult↗
PubMed1996

Arterial complications after knee arthroplasty: 4 cases and a review of the literature.

We reviewed 40 cases of arterial complications after total knee replacement from the literature and report 4 of our own cases. The incidence is low (0.03%-0.2%), but the prognosis is poor, with death or amputation in one fourth of the cases. Preexisting arterial insufficiency, absent pedal pulses, arterial calcification on plane radiographs, femoro- popliteal/distal grafts are all predisposing factors. Therefore, preoperative risk factor evaluation as well as rapid and adequate handling in case of bleeding and/or ischemic complications pre- and postoperatively are crucial. Cooperation with a vascular surgeon is also essential.

Aged↗
PubMed1996

Thromboprophylaxis with a low molecular weight heparin (tinzaparin) in emergency abdominal surgery. A double-blind multicenter trial.

In this prospective randomized double-blind study the thromboprophylactic effect of postoperative low molecular weight heparin (tinzaparin) was compared with placebo in 80 patients undergoing emergency abdominal surgery. The fibrinogen uptake test was used but because of withdrawal of the labelled fibrinogen from the market the calculated number of patients was not reached. However, this is one of the few studies in emergency abdominal surgery we thought it important to report. The frequency of deep vein thrombosis was reduced with prophylaxis from 22% (95% conf. intervall 11-38%) to 8% (2-21%), a risk reduction of 65%, which is however not significant. Together with data from the few previously published studies it can be concluded that patients undergoing emergency abdominal surgery seem to benefit from prophylaxis, which should be instituted either before operation or at latest 24 hours after. The exact prophylactic relation between pre- and post-operative start would, however, require a separate, randomized study.

Abdomen↗
PubMed1996

The prevalence of chronic lower-limb ulceration has been underestimated: results of a validated population questionnaire.

A validated population questionnaire was used to survey 12,000 randomly selected inhabitants, aged 50-89 years, in two defined regions of Sweden. The sample included 7 per cent of the total population in the age interval. Overall response rate was 91 per cent. Open ulcers were reported by 306 subjects and 143 (47 per cent) agreed to be examined. The false-positive response rate was high (43 per cent). The observed point prevalence of open leg ulcers was 0.63 (95 per cent confidence interval 0.54-0.72) per cent of the total population. The overall prevalence of leg ulcer history (open plus healed) in the population was estimated to be around 2 per cent and the ratio of open: previous ulcers was 1:2. This study shows a point prevalence more than double that expected, indicating a high rate of self treatment. Assessments of leg ulcer prevalence through the health care system, without knowledge of the rate of self care, measure only the workload of health care professionals. The problem of leg ulcers has generally been underestimated.

Aged↗