PubMed Health⌕ Search

Biomedical subjects

H Dige-Petersen

Publications and source records attributed to H Dige-Petersen.

At least 55 records · Page 3Linked to original sources

Gastric emptying of liquid meals. A study in 88 normal persons.

Using a gamma camera, gastric emptying of a nutrient liquid meal labelled with 99m-Tc-DTPA has been studied in 88 normal subjects in order to assess reproducibility and to establish the range for gastric emptying under standardized conditions. The emptying patterns were visualized as time-activity curves. The early phase (0-15 min) was characterized by a rapid emptying taking place during the first minutes and a subsequent period of almost no emptying (plateau) lasting for up to 20 minutes, followed by an almost constant emptying in the later phase (15-60 min). In the early and later phase mean percentages emptied were 13% (range, 0-30) and 49% (range, 9-79), respectively. The intraindividual variation was larger for repeated tests of months' than of days' intervals, the coefficients of variation in the early phase being on the average 72% (range, 29-175) and 37% (range, 13-128), respectively. During the later phase less variation was seen. Irregular deviations from the standard pattern were observed in the curves, indicating gastric contractions and duodenogastric reflux. Serial scintifotos revealed that the radionuclide labelled gastric content was not uniformly distributed within the stomach. This activity distribution, affected by the subject's position during emptying, seemed to occur instantaneously and to be completed within a few minutes. These findings allow the standardized radioisotope technique to be used for physiological, pathophysiological and pharmacological studies, when performing consecutive studies in the same individual within days or a few weeks. The wide reference interval for gastric emptying of this liquid meal invalidates the method as a clinical diagnostic tool.

Adult↗

Somatic manifestations in children suspected of having been maltreated.

The present study revealed an incidence of maltreatment of 26.8 in 100,000 children under 15 years of age, higher than previously assumed. The sample comprises 41 children suspected of having been maltreated. A systematic examination included radiography and isotope scintigraphy of the skeletal system. In 9 cases the diagnosis was not confirmed, in 23 confirmed, and in 9 children it seemed likely. The most common form of maltreatment was physical violence with bruises. A total of 6 fractures were demonstrated. Three children had been exposed to sexual abuse. Intracranial haematoma, of long standing, was found in one child. Thirteen of the children (40%) were of short statute, their height and weight below the 25th percentile. Among 27 children examined by X-rays 16 (59%) had delayed skeletal maturation. Disturbances of growth, as well as behavioural abnormalities, were particularly striking in this group of patients. The findings suggest that even the slightest suspicion of maltreatment should lead to a general medical evaluation without delay.

Adolescent↗

The reliability of measuring left ventricular ejection fraction by radionuclide cardiography: evaluation by the method of variance components.

A statistical model based on the method of variance components was applied to obtain confidence statements for single and repeat determinations of left ventricular ejection fraction by radionuclide techniques. With this approach variance caused by individual factors in the measurement procedure is estimated to allow calculation of confidence intervals based on single measurements and the detection limits for changes. Six study groups made up of a total of 143 subjects were examined by both multigated equilibrium and first pass imaging. Under favourable conditions (with an updated gamma camera and experienced observer) the 95% confidence interval with a single measurement of left ventricular ejection fraction by equilibrium imaging was +/- 3 ejection fraction units, compared with +/- 6 units with the first pass technique (one ejection fraction unit = 1/100 of the possible values from 0.00 to 1.00). The minimal significant changes (at the 5% level) in measured equilibrium left ventricular ejection fraction at intervals of 15 min, 3 days, 1, 3, and 4 weeks were +/- 4, +/- 4, +/- 5, +/- 5, and +/- 6 units, respectively. The corresponding minimal detectable changes in a subject's "true" left ventricular ejection fraction for the same intervals were +/- 7, +/- 7, +/- 10, +/- 10, and +/- 12 units respectively. With first pass imaging, only average values for the variation at repeat determination could be calculated. The minimal significant change in measured first pass left ventricular ejection fraction was +/- 7 units, and the minimal detectable change in "true" left ventricular ejection fraction was +/- 14 units. Measurements of left ventricular ejection fraction by equilibrium technique were generally more reproducible than first pass determinations because the variability caused by study acquisition, observer analysis, and residual errors was smaller. The method of variance components appears to be well suited to the evaluation of quantitative biological measurements in clinical use. The popularity of established procedures may obscure the lack of basic information about method evaluation.

Adult↗

Right and left ventricular ejection fractions: relation to one-year prognosis in acute myocardial infarction.

Right and left ventricular ejection fractions (RVEF and LVEF) were measured by radionuclide angiography in 423 patients with acute myocardial infarction (AMI). All investigations were performed at hospital discharge. Of 304 patients with first AMI, 26% had normal ejection fractions, 10% had a decrease in RVEF only, 46% a decrease in LVEF only, and 18% decrease in both RVEF and LVEF. Death from cardiac causes occurred in 52 patients in a one-year follow-up period. A reduced RVEF at hospital discharge had little, if any, relation to one-year mortality. In contrast, there was an inverse curvilinear relationship between LVEF and one-year cardiac mortality.

Adult↗

Effects of combined therapy with amiloride and hydrochlorothiazide on plasma and total body potassium, blood pressure, and the renin-angiotensin-aldosterone system in hypertensive patients.

After a run-in period of 8 weeks on a regimen of hydrochlorothiazide (HCT, median dosage 75 mg/day), patients with essential hypertension were randomly allocated to continued hydrochlorothiazide therapy (Group I) or additional treatment with amiloride (Group II, median dosage 15 mg/day, or 5 mg per 25 mg hydrochlorothiazide) for the following 12 weeks. Thereafter all the patients were changed to treatment with a fixed combination tablet containing 5 mg amiloride and 50 mg hydrochlorothiazide (Moduretic), keeping the thiazide dosage unchanged for an additional 12 weeks. In Group I patients there was no change in plasma potassium, total body potassium content or the renin-angiotensin-aldosterone system during the 12 weeks on HCT. When the treatment was changed to Moduretic, significant increases were found of 10% in plasma potassium and 3% in total body potassium content. No important stimulation of the renin-angiotensin-aldosterone system was found. In Group II patients addition of an average of 15 mg amiloride to the hydrochlorothiazide treatment led to significant increases in plasma potassium and total body potassium content of approximately 15% and 4%, respectively. There was also a significant increase in the plasma concentrations of renin, angiotensin II and aldosterone. Reducing the average dose of amiloride to 7.5 mg/day by use of Moduretic did not lead to decrease in plasma potassium or total body potassium content. Plasma concentrations of renin, angiotensin II, and aldosterone were decreased, but the individual changes varied markedly and no significant overall change was found.

Adult↗

Dose-response relationship in normal subjects of prenalterol, a beta-adrenergic agonist with positive inotropic and resistance lowering effects.

The acute haemodynamic effects of increasing doses of parenterally administered prenalterol-a beta-adrenergic stimulating drug-were assessed in normal subjects by means of radionuclide ventriculography. Prenalterol induced dose-related increases in the left ventricular ejection fraction and the systolic pressure end-systolic volume ratio. Left ventricular end-systolic and end-diastolic volumes decreased to the same extent accounting for an unchanged stroke volume. Cardiac output increased due to a rise in the heart rate. Systolic blood pressure increased, whereas diastolic and mean blood pressure remained unchanged. Calculated total peripheral resistance decreased significantly. The maximum effect of prenalterol on cardiac performance occurred with a dose of 18 to 36 micrograms/kg. Plasma concentrations of prenalterol showed large interindividual variations. In conclusion, prenalterol improves the pump function of the normal heart and causes a fall in peripheral vascular resistance, implying a reduction of the load on the heart. These effects may prove beneficial in the treatment of acute heart failure.

Adrenergic beta-Agonists↗

Evaluation of intravenous radionuclide angiography in detection of occlusive disease of the iliac arteries.

Radionuclide angiography (angioscintigraphy) of the iliac arteries was performed in 173 patients consecutively referred for arterial insufficiency of the legs. In 83 of the patients femoral angiography was also performed. The interobserver variation was evaluated by the agreement indices, kappa (K) and weighted kappa (Kw). For angiography the interobserver agreement was high (K and Kw 0.65 and 0.77 respectively). For angioscintigraphy the agreement between observers was fair (K = 0.52, Kw = 0.68), and equal to the intraobserver agreement (K = 0.55, Kw = 0.65). The comparison between angioscintigraphy and angiography gave K-values of 0.22-0.31 and Kw-values of 0.37-0.48. The nosographic sensitivity of angioscintigraphy was 61%, the nosographic specificity was 93%, and the predictive value for both a positive and a negative test was 83%. The prevalence of occlusion or severe stenosis was 34%. Inguinal pulse palpation detected 48% of iliac occlusions. It is concluded that the reliability of angioscintigraphy in the diagnosis of iliac arterial occlusive disease is acceptable for a non-invasive, rapid, inexpensive and widely available screening procedure. Although anatomical details are not visualized the information obtained is useful for the detailed planning and choice of subsequent diagnostic and therapeutic procedures. The method is well suited for repeat studies and may be modified to include the femoral arteries.

Adult↗

Effects of amiloride on plasma and total body potassium, blood pressure, and the renin-angiotensin-aldosterone system in thiazide-treated hypertensive patients.

Total body potassium content, plasma potassium concentration, blood pressure, and plasma concentrations of renin, angiotensin II, and aldosterone were measured in patients with essential hypertension after a run-in period of 8 wk on a regimen of hydrochlorothiazide (median dosage 75 mg/day). Patients were then randomly assigned to continued hydrochlorothiazide therapy (group I) or to receive adjunctive treatment with amiloride (group II, median dosage 15 mg/day or 5 mg per 25 mg hydrochlorothiazide) for the following 3 mo. There were no changes in group I patients during 3 mo on hydrochlorothiazide in plasma potassium, total body potassium content, or the renin-angiotensin-aldosterone system. Blood pressure was also unchanged. In group II patients addition of amiloride to hydrochlorothiazide induced a rise in plasma and total body potassium of approximately 15% and 4%. The potassium-retaining effect was maintained throughout the 12-wk period, although the maximal changes were observed after 8 wk of treatment. Supine blood pressure did not change, but there was a significant decrease in standing systolic blood pressure. There was a marked rise in plasma concentrations of renin, angiotensin II, and aldosterone.

Adult↗

Intravenous radionuclide angioscintigraphy and computer tomography in cerebral arteriovenous malformations.

In 25 patients with cerebral arteriovenous malformation (AVM) computer tomography (CT) was compared with dynamic and static intravenous radionuclide angioscintigraphy (99mTc-labelled red blood cells). The diagnosis was verified by arteriography performed 2-20 years prior to this study. Scintigrams and CT-scans were evaluated 'blindly' by independent observers after pooling of the patient studies with 20 and 20 control studies, respectively. Only images strictly characteristic of AVM were classified as positive. The nosographic sensitivity of both methods was about 70%, in a few patients they were supplementary. Neither CT nor scintigraphy were able to detect lesions of less than 2 cm diameter. The methods seem to be of equal and rather high specificity, and are both well suited as screening procedures. CT provides additional information as to other intracranial abnormalities. The screening method of first choice when AVM is suspected may be CT or angioscintigraphy, depending on availability of equipment and expertise.

Adolescent↗

A comparison of 99Tc and 123I scintigraphy in nodular thyroid disorders.

Out of 450 patients referred for thyroid scintigraphy 83 consecutive patients with nodular goitre were selected for dual scintigraphy with 99mTc and 123I. Seventy-four patients had one or more palpable nodules and the other nine patients had palpably diffuse goitres with one or more nodules on the routine 99mTc scintigram. For the comparison of scintigrams an eight level colour display was used, and regional differences between the 99mTc and 123I scintigrams were defined as a minimum of 25% (2 colour levels) variation of the relative activity in well defined areas. Thirteen patients, i.e. 16% of those with nodular goitre, had discordant scintigrams. All 13 patients had non-malignant thyroid disorders, (simple goitre, radio-iodine treated hyperthyroidism, autonomous adenoma, subacute thyroiditis, Riedel's and lymphocytic thyroiditis). The diagnosis was verified histologically in eight of these patients. Eight of the 13 patients had a high 99mTc activity relative to 123I, five patients showed the opposite discrepancy. Another 5 patients with a follicular or mixed follicular thyroid carcinoma had identical scintigrams. These findings indicate that 123I does not offer such diagnostic advantages over the cheap and readily available 99mTc, that its use for routine scintigraphy of the thyroid gland seems to be justified at present.

Adenoma↗

Lung split function test and pneumonectomy. A lower limit for operability.

Regional 133Xe ventilation/perfusion studies were used to predict residual lung function after pulmonary resections. The accuracy of the method was good as checked by postoperative spirometry in 11 patients. In 25 patients with impaired lung function and pulmonary cancer, who were consecutively selected for surgery, the predicted postoperative maximal breathing capacities (MBC) ranged from 17 to 41 l/min-1 m-2. No patients became permanent pulmonary invalids. One patient died from myocardial infarction, 7 had transient pulmonary insufficiency and 17 patients survived operation without complications. Perfusion studies alone proved as reliable as perfusion/ventilation studies.

Aged↗