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D Bergqvist

Publications and source records attributed to D Bergqvist.

At least 253 records · Page 14Linked to original sources
PubMed1993

Volume blood flow measurements with a transit time flowmeter: an in vivo and in vitro variability and validation study.

A transit time flowmeter, Transonic TC101 (Transonic Inc., USA) has been evaluated to study volume flow. Two flow probes, 4 and 6 mm, were used. The experiments were carried out in vivo on the carotid arteries (n = 16) in sheep and in vitro against a pre calibrated rotational pump. Exsanguination measurements, n = 32, were used for the calculation of the error of measurement in vivo. The error of measurement in vitro was calculated on 11 different flow rates from 0 to 150 ml min-1. The variability in vivo was evaluated using data from 10, 30 s measurement periods with a 30 s pause between measurements. The variability in vitro was evaluated at three flow rates (46, 78, and 113 ml min-1). Five 1-min measurements with a 1-min pause between measurements were made. The error of measurement in vivo was 12.05% and in vitro 5.50% (4 mm probe) and 14.90% (6 mm probe). In vivo the variability was between 1.1 and 4.4% and in vitro between 1.5 and 11.2%. The correlation coefficients between the flowmeter on the one hand and exsanguination and the rotational pump on the other were 0.99, 0.99 (4 mm probe) and 0.98 (6 mm probe). It is concluded that the flowmeter has a small variability and error of measurement both in vivo and in vitro.

Animals↗
PubMed1993

Non-invasive measurement of pulsatile vessel diameter change and elastic properties in human arteries: a methodological study.

A recently developed ultrasound phase-locked echo-tracking system makes it possible to measure non-invasive pulsatile vessel diameter changes, and, in combination with blood-pressure measurement, to calculate pressure strain elastic modulus (Ep) and stiffness (beta). The reproducibility in measurements of pulsatile diameter changes with this system was evaluated. Also the precision of indirect blood-pressure measurements, as compared to the simultaneously measured intra-arterial blood pressure was tested. The resulting reproducibility in pressure strain elastic modulus (Ep) and stiffness (beta) was evaluated. Intra-observer variabilities in measuring pulsatile diameter changes were 16% for the abdominal aorta, 10% for the common carotid artery, and 15% for the common femoral artery, respectively. Intra-observer variabilities for Ep and beta were 21% for both in the abdominal aorta, 17% for both in the common carotid artery, and 18% for both in the common femoral artery, respectively. There were only small differences in indirect and direct measurement of systolic blood pressure, whereas indirect blood pressure measurement systematically overestimated the diastolic blood pressure, on average by 20%. The variabilities in indirect blood pressure measurements were 2% for the systolic and 3% for the diastolic blood pressure, respectively. Inter-observer variability in the investigation of the common carotid artery was 10% for the pulsatile diameter changes, and 21% and 23% for Ep and beta, respectively. Thus, the echo-tracking system represents a reliable system for estimation of pressure strain elastic modulus and stiffness. However, Ep and beta are systematically underestimated by 25-30%, when used in combination with indirect blood pressure measurements.

Adult↗
PubMed1993

Cost/benefit aspects on thromboprophylaxis.

Several studies have shown thromboprophylaxis of any kind to be more cost-effective than no prophylaxis or general diagnostic surveillance and selective treatment. Little has been written on low molecular weight heparins from the cost-effectiveness point of view. This preliminary study shows low molecular weight heparin to be more cost-effective than standard low-dose heparin in most situations of prophylaxis.

Abdomen↗
PubMed1993

Long-term prophylaxis following orthopedic surgery.

Recently there has been an increasing interest in long-term prophylaxis as it has become known that thromboembolic events may occur fairly late in the postoperative course. However, the scientific knowledge on long-term prophylaxis is small and adequately performed studies must be done before general recommendations are made.

Follow-Up Studies↗
PubMed1993

Thromboprophylaxis in emergency surgery.

Except for hip fracture surgery, emergency surgery has been only exceptionally studied concerning thromboprophylaxis. There are, however, several reasons to believe the frequency to be fairly high and that the patient group would be in need of prophylaxis. This paper discusses various emergency situations and also gives the design for an ongoing controlled study on the effect of postoperative start of thromboprophylaxis with low molecular weight heparin in emergency abdominal surgery.

Abdomen↗
PubMed1993

Antithrombotic properties of a truncated recombinant tissue factor pathway inhibitor in an experimental venous thrombosis model.

The aim of this study was to investigate whether a truncated recombinant tissue factor pathway inhibitor (rTFPI1-161) had an antithrombotic effect comparable to low-molecular-weight (LMW) heparin. A randomized double-dummy study was conducted with 40 rabbits in 6 groups. An experimental thrombosis was induced in the jugular veins by a combination of destroyed endothelium and restricted blood flow. Group 1 was given placebo; group 2, LMW heparin 60 anti-factor Xa units/kg; group 3, rTFPI1-161 0.1 mg/kg; group 4, rTFPI1-161 1.0 mg/kg and group 5, rTFPI1-161 10.0 mg/kg. rTFPI1-161 reduced the thrombus weights in all treated groups, with a significant effect in doses between 1.0 and 10.0 mg/kg compared to placebo. The frequency of thrombosis was significantly reduced in all treated groups. No hemorrhagic side effects were noted. In conclusion, rTFPI1-161 (1.0-10.0 mg/kg) has an antithrombotic effect comparable to that of LMW heparin.

Animals↗
PubMed1993

Does low-dose acetylsalicylic acid prevent stroke after carotid surgery? A double-blind, placebo-controlled randomized trial.

BACKGROUND AND PURPOSE: The aim of this randomized double-blind, placebo-controlled trial was to evaluate whether neurological deficits could be prevented with low-dose acetylsalicylic acid (ASA) as an adjunct to carotid endarterectomy. METHODS: A total of 232 patients were randomized to two groups, 75 mg/d ASA starting preoperatively and continued for 6 months (n = 117) or placebo (identical tablets) (n = 115). The patients were followed up regularly for 1 year. RESULTS: The groups were well matched regarding laboratory data and indication for operation. The number of patients with intraoperative or postoperative stroke without complete recovery within 1 week were 0 and 2 at 30 days and 6 months, respectively, in the ASA group, compared with 7 and 11 in the placebo group (P = .01). Including all neurological events within 6 months, this was found in 15 patients in the ASA group compared with 24 in the placebo group (P = .12). Mortality was 0.8% and 3.4% at 30 days and 6 months, respectively, in the ASA group. In the placebo group, the corresponding figures were 4.3% and 6.0%, respectively (P = .12). The intraoperative bleeding did not differ between the groups nor did the number of reoperations due to bleeding or other complications related to pharmacology. CONCLUSIONS: This study indicates that low-dose ASA (75 mg/d) reduces the number of postoperative strokes without complete recovery within 1 week. Overall neurological events are insignificantly reduced, as also mortality. The use of low-dose ASA (75 mg) seems safe and effective in reducing cerebrovascular events after carotid endarterectomy.

Adult↗
PubMed1993

99Tcm-sestamibi uptake in the leg muscles and in the myocardium in patients with intermittent claudication.

99Tcm-Sestamibi has now replaced 201Tl as a cardiac imaging agent. In addition to the myocardial uptake there is also a considerable uptake in the striated muscle, which may be used for analyzing the muscular perfusion. Sixteen patients with intermittent claudication were investigated with 99Tcm-Sestamibi-SPECT (single photon emission computerized tomography) in order to visualize coronary ischemic disease. After the registration of the myocardial perfusion they were also studied regarding their leg muscle perfusion. This was done at rest and during standardized stress test using a bicycle ergometer. In 10 of the patients there was an increase in the isotope uptake in the myocardium from work to rest > 10% reflecting pronounced myocardial ischemia, which, however, was symptomatic in only 4 of the patients. The muscular uptake in the myocardium of 99Tcm-Sestamibi in the thigh increased significantly from rest to exercise (P < 0.01), while it remained unchanged in the calf muscle. There were no significant correlations at rest between the ratio of the right and left systolic blood pressure in the ankles and the ratio between the right and left isotope uptake in the calves, but the increase in the isotope uptake from rest to work correlated with the blood pressure ratio at r = 0.79, P < 0.01 (anterior projection) and r = 0.71, P < 0.01 (posterior projection).

Adult↗
PubMed1993

Estrogen and progesterone receptors in vessel walls. Biochemical and immunochemical assays.

The purpose of the present investigation was to examine the estrogen and progesterone receptor status in arterial and vein walls in women and men. Biopsies from uterine arteries and veins were obtained from 14 fertile and six post menopausal women. Biopsies from saphenous veins were obtained from eight fertile women, 12 post menopausal women and 12 men. Comparative receptor assays were performed with ligand technique and monoclonal antibodies. Immunohistochemical localization of estrogen and progesterone receptors was performed using monoclonal antibodies. The ligand technique revealed estrogen and progesterone receptors in low frequency in the uterine vessels but the monoclonal antibodies showed low receptor level in all arterial and vein samples. There was no statistical difference between fertile and post menopausal women. In the few nuclear fractions examined, both estrogen and progesterone receptors were measurable. Estrogen receptors were found in all peripheral vein samples from fertile women but not in all samples from post menopausal women and men. Progesterone receptors were detected in almost all samples of peripheral veins. There were significant differences with higher levels of estrogen receptors in cytosol and nuclear fraction and of progesterone receptors in nuclear fraction, all assayed with monoclonal antibodies, in uterine veins from fertile women compared to peripheral veins from fertile women, post menopausal women and men, respectively. These data indicate that the hormonal regulation of peripheral vein walls is different than that of the uterine vessel.

Adult↗
PubMed1993

Bilateral renal autotransplantation with direct pyelocystostomy in a patient with frequent disabling nephroureterolithiasis. Case report.

A case with disabling nephroureterolithiasis, initially most frequent from the right side, later also from the left kidney, is presented. Conservative treatment did not improve the condition and bilateral renal autotransplantation with pyelocystostomies was performed. Follow-up so far has been uneventful. In highly selected cases this is a useful alternative treatment.

Cystostomy↗
PubMed1993

Endothelial influence on vessel wall induced vasospasm after balloon angioplasty.

Aortic segments from 47 New Zealand rabbits were used, of which 14 were denuded of endothelium. Balloon angioplasty was performed on the aortic segments in vitro. The inner surfaces were perfused and the perfusates then given to vessel segments with or without endothelium. The contraction evoked was then counteracted by adding either vasoactive intestinal polypeptide (VIP), substance P (SP), acetylcholine (ACh), or nitroglycerin (NTG) in increasing concentrations. Perfusates from aortic segments with or without endothelium and previously treated with angioplasty induced vasoconstriction of similar magnitude in the segments used for vasomotor investigation irrespective of whether the endothelium was intact in these or not. Endothelial dependent dilators (ACh, SP) did not counteract the contraction whereas endothelial independent dilators did (NTG, VIP). Neither the induction nor the reversal of vessel wall induced vasoconstriction after balloon angioplasty seems to depend on the presence of endothelial cells.

Acetylcholine↗
PubMed1993

Prostanoid release immediately after balloon angioplasty in three models of atherosclerosis in rabbits.

OBJECTIVE: To evaluate the effect of angioplasty on the production of prostanoids in atherosclerotic vessels in rabbits. DESIGN: Open study. MATERIAL: 38 Rabbits. INTERVENTIONS: Rabbits in group A (n = 12) were given a cholesterol rich diet (2%) for 10 weeks, and then treated with angioplasty. Rabbits in group B (n = 11) were given a cholesterol rich diet for 10 weeks, and then returned to a normal diet until the serum cholesterol concentration returned to the reference range (a further 12 weeks). Rabbits in group C (n = 15) were anaesthetised, and a 3 mm balloon was introduced into the right femoral artery, fed 20 cm proximally, inflated, and pulled twice along the aorta; the animals were then given a cholesterol rich diet (2%) for eight weeks, and treated with angioplasty. MAIN OUTCOME MEASURES: Serum cholesterol concentrations were measured once a week. Prostacyclin and thromboxane were measured as 6-keto prostaglandin F1 alpha and thromboxane B2 in both treated and control segments of aorta. RESULTS: 15 Rabbits died while atherosclerosis was being induced, leaving 23 for analysis. Angioplasty reduced the amounts of prostanoids released in animals in which the atherosclerosis had been induced by diet alone. When endothelial injury and diet were used together, there was no difference between the treated and control segments in the amounts of prostanoids released. CONCLUSION: These findings could be of use in the comparison of methods used to induce atherosclerosis, and in the study of the mechanisms of thrombosis after transluminal angioplasty.

6-Ketoprostaglandin F1 alpha↗
PubMed1993

Expansion pattern and risk of rupture of abdominal aortic aneurysms that were not operated on.

OBJECTIVE: To analyse the outcome of selective management of patients with abdominal aortic aneurysms, the expansion patterns of the aneurysms, and the factors that influenced the rate of rupture. DESIGN: Retrospective study. SETTING: Malmö General Hospital, Lund University, Malmö, Sweden. SUBJECTS: 155 patients (96 men and 59 women) with abdominal aortic aneurysms who were not selected for operation for whatever reason were included in the study immediately after their first ultrasound scan. MAIN OUTCOME MEASURES: Mortality, expansion rate (mm/year) measured on ultrasound scan, and rate of rupture of aneurysm. RESULTS: Median aneurysmal diameter was 40 mm (range 20-80), and length (n = 106) 70 (range 28-140). The patients were followed up for a median of 3.4 years (range 0-10.2). A total of 107 patients died and in 21 the aneurysms ruptured (4 were operated on and survived). Thirteen patients were re-evaluated and operated on electively. Ultrasonography was repeated in 98 patients, the median expansion rates (mm/year) were 3.1 (diameter) and 1.9 (length). There was a significant linear relationship between initial size (diameter and length) and rate of expansion of diameter. The risk of rupture was greater in larger aneurysms that were expanding more quickly. The cumulative mortality was not affected by the 21 aneurysms that ruptured. CONCLUSION: Selective management of patients with aortic aneurysms is justified.

Aged↗
PubMed1993

[Cost-effectiveness of the prevention of postoperative thromboembolism].

Awareness of cost-effectiveness aspects has become increasingly important within the health care sector in times of constrained resources. Health economics deal with methods of making choices under conditions of uncertainty and provide models for decision making. A key question is to compare alternative strategies. Within the field of prophylaxis against venous thromboembolism general thromboprophylaxis is cost-effective provided that the frequency of deep vein thrombosis is higher than 10%. Diagnostic screening and selective treatment of detected thrombosis is always the least cost-effective alternative. Although detailed analyses are still lacking it seems as if the use of low molecular weight heparins is more cost-effective than unfractionated low dose heparin. Besides saving lives by preventing fatal pulmonary embolism an adequate thromboprophylaxis also will provide monetary savings.

Cost-Benefit Analysis↗