Biomedical subjects

W D Hiltmann

Publications and source records attributed to W D Hiltmann.

22 records · Page 2Linked to original sources

PubMedDate not supplied

[Theory of methods to compare lead fields in electrocardiography (author's transl)].

A method is theoretically described to test the accuracy of various lead system of the ecg. The priniciple of this method consists in the following procedure. The heart position is changed maximally in a proband by varying the position of the body and by deep inspiration and exspiration. If the lead field is parallel, the recorded vector loops should by conventible into each other by merely rotating them electronically, because the cardiac determinants of the veg will scarcely be changed by a change in heart position. The deformations of the veg in the edgeside and broadside view are an appropriate measure of the inhomogenities (the "accuracy") of the lead field, mostly caused by the configuration of the chest and the inhomogeneous conductivity of the tissues and the resulting lack of parallelity in the lead lines of the field. Criteria to test the form of the vector loop are developed, measuring quantitatively the similarly of the loops recorded in different heart positions. The "best" lead is regarded to be that with greatest similarity of the loops in extreme dislocations of the heart.

Electrocardiography↗

PubMedDate not supplied

[Lung function during tocolysis with beta-stimulators and beta-1-blockers].

The pulmonary function during pregnancy is foremost changed by the elevated diaphragm, which reduces the functional residual capacity. The lungs are less extended, so that the airway resistance increases. The application of a beta-mimetic drug for tocolytic therapy could reduce the airway resistance. Because an additional selective beta-1-blocking drug for cardioprotection could interfere with this effect, the pulmonary function in pregnancy during tocolytic therapy was investigated by body plethysmography in 20 woman of the third trimester of gravidity. There were no apparent differences in the pulmonary function in these woman when an additional selective beta-1-receptor blockade was performed. The airway resistance even diminished during the beta blockade. This unexpected result is probably due to an stabilizing effect of the betablocker on the body fluid and the permeability of capillary membranes during tocolytic therapy.

Adrenergic beta-Agonists↗

PubMedDate not supplied

[The effect of beta-stimulation and beta-1-blockade on the motility of the upper urinary tract].

18 patients with severe congestion of the urinary tract in pregnancy were treated by implantation of ureteral catheters for intermittend exoneration. Before and during the infusion of 2 micrograms/min Fenoterol the basal tone, the frequency and amplitude of the contractions of the renal pelvis were measured after retrograde filling with increasing volumes. 45 min after the i.v. application of 10 mg Metoprolol the measurements were repeated under the same conditions. During the infusion of Fenoterol there was a significant decrease of the frequency and amplitude of the contractions of the renal pelvis. Whereas at low retrograde filling volumes the basal tone in the renal pelvis decreased, at higher filling volumes - because of the concomittant deteriation of the urine transport capacity - an increase of the basal tone could be found. The relaxant effects of the beta-stimulation on the upper urinary tract could be diminished by the application of the beta-1-blocker Metoprolol; a complete compensation however was not possible.

Adolescent↗

PubMedDate not supplied

[A knowledge-based system for the interpretation of pelvimetric findings].

Digital Image Intensifier Radiography (DIR) as well as Nuclear Magnetic Resonance Tomography (NMR) using an especially developed imaging routine for pelvimetry are suitable tools for the assessment of the anatomical conditions when mechanical problems are supposed to occur during birth (cephalopelvic disproportion, breech presentation). A concept for an optimised evaluation procedure of these imaging techniques has been developed, including: a more elaborate measuring protocol, easily and precisely executable due to appropriate software packages being implemented in the diagnostic units, calculation of obstetrically relevant parameters not deriving immediately from the imaging procedures. This is possible by means of multiple regression analysis of a data base from 467 evaluated female pelvis computed tomograms, calculation of intrapelvic soft tissue place requirements by means of correlative analysis of female computed tomograms and weight-/height-index, empirical determination of cut off values in borderline pelvi-fetometric constellations evaluating 190 births by means of logistic regression of the according pelvic-fetometric data. The calculations necessary to obtain all these parameters are implemented in a software package which also contains an algorithm for the general characterisation of an individual pelvis. Thus, a rather sophisticated knowledge base for pelvic assessment becomes easily accessible.

Adult↗