Search PubMed⌕ Search

Biomedical subjects

H Worth

Publications and source records attributed to H Worth.

At least 109 records · Page 6Linked to original sources
PubMed1985

Long-term follow-up of pulmonary hypertension in patients with and without anorectic drug intake.

Over a period of up to 18 years, 24 patients (mean age: 33.8 years) with primary vascular pulmonary hypertension (PVPH) of unknown aetiology (group A) and 18 subjects (mean age: 45.3 years) with PVPH due to anorectic drug intake (group B) were comparatively studied. The following main tendencies became apparent: 1) The 10-year cumulative survival rate in group A (0.31) was lower than in group B (0.63). 2) Patients of group A showed more marked X-ray and ECG signs of pulmonary hypertension and right ventricular hypertrophy in comparison with group B. In contrast to group B, the ECG signs of hypertrophy in group A increased during the observation period. 3) Mean pulmonary artery pressure (PAP) significantly increased in group A (from 48.8 to 61.0 mmHg), while it decreased (from 47.6 to 33.3 mmHg) in group B. 4) The diameter of the descending branch of the right pulmonary artery increased with rising PAP only in group A, while the relationship between PAP and the Sokolow-Lyon index was significant only for the whole group of PVPH patients but not for the subgroups A and B. A regression of pulmonary hypertension in patients with anorectic drug intake was obvious, in contrast to the course in patients with PVPH of unknown aetiology.

Adolescent↗
PubMed1984

[Acute respiratory failure in a medical intensive care unit. Incidence and prognosis].

Acute respiratory failure had occurred in 89 of 1594 patients in a medical intensive care unit (5.6%), 26.8% of all patients (332) on long-term mechanical ventilation. Compared with the other chronically ventilated patients those with acute respiratory failure averaged a lower age, the proportion of women was higher and the duration of ventilation longer. The death rate was significantly higher (78.7% compared with 58.3%). The important prognostic factors included the underlying disease, additional abnormal organ function, severity of pulmonary gas exchange abnormality, and advanced age. If there was septicaemia, peritonitis, liver cirrhosis with bleeding oesophageal varices or polytrauma with acute renal failure the death rate was over 80%; after hypovolaemic shock, pancreatitis or postoperative pulmonary failure it was less than 65%. Patients who had abnormal function of at most one other organ in addition and an inspiratory arterial pO2 difference below 250 mm Hg, measured 12 hours after onset of mechanical ventilation, had a relatively favourable prognosis with a death rate of 33%, while in the other groups of patients it was 86-100%.

Acute Disease↗
PubMed1984

[Electromyographic determination of the fatigability of respiratory and leg muscles before and after aortocoronary bypass operation].

To study the effect of postoperative confinement to bed on respiratory muscle fatigue, 31 male subjects (age, 34-66 years) undergoing coronary artery revascularization were examined. Fatigue of both respiratory muscles (musculi intercostales externi) and leg muscles (musculus gastrocnemius) was determined by electromyography prior to and 7 and 12 days after operation. Additionally, oscillatory resistance to breathing and phase angle were measured. Pre- and postoperative routine lung function tests were performed. A comparison between preoperative and postoperative measurements reveals that respiratory as well as leg muscle fatigue occurred at higher loads during the preoperative and the second postoperative than during the first postoperative determination. After surgery vital capacity, total lung capacity, 1-second capacity, and, to a lower extent, thoracic gas volume were diminished, while specific airway conductance, oscillatory resistance to breathing, phase angle, residual volume, and relative 1-second capacity remained unchanged. The constancy of the latter parameters indicates that neither airway obstruction nor a significant restriction of the lung and/or thorax occurred due to surgery. Therefore, the increase of respiratory muscle fatigue after surgery may more probably be attributed to a lack of training of respiratory muscles which may contribute to limitation of ventilation in bedridden patients.

Adult↗
PubMed1984

[Fibrinolysis in right ventricular thrombus].

After fracture of his toes, a 34-year-old male patient developed deep leg vein thrombosis and subsequent pulmonary embolism. Because of progressive heart enlargement, 2D-echocardiography was performed. A floating mass measuring 4.5 cm X 3.5 cm was found in the right ventricle. On account of the deep leg vein thrombosis and the lung perfusion deficits detected by scintigraphy, the floating mass was thought to be a thrombus. Because of the severity of the patient's state and the lack of success of a heparin therapy with 32,000 IU/d, fibrinolytic treatment with streptokinase was started. After initial improvement in pulmonary gas exchange the patient died about 7 hours later from progressive cardiopulmonary insufficiency. Necropsy revealed a smaller right ventricular thrombus than that seen by echocardiography. There were typical surface erosions caused by the fibrinolytic treatment. Many younger and older emboli which in part were fragmented could be shown in the pulmonary vessels. A fragmentation of the right ventricular thrombus and subsequent lethal occlusion of pulmonary vessels had to be considered. With respect to the course of the described case and some case reports in the literature we think fibrinolysis is more dangerous than surgical thrombectomy in right ventricular thrombosis.

Adult↗
PubMed1983

[Long-term therapy of bronchial asthma].

The prerequisite for an effective therapy of bronchial asthma is a sufficiently precise characterization of the disease. Based on the demonstration of allergy or not asthma can roughly be subdivided into an extrinsic (allergy present) and an intrinsic type (allergy not demonstrable). If exposition to allergens cannot be avoided, specific hyposensibilization has to be considered in the treatment of extrinsic asthma. Several drugs are available for the management of reversible airway obstruction in both types of asthma mentioned above. Basic pharmacological mechanisms, side effects and indications for systemic and inhalation therapy of beta-sympathicomimetics, methylxanthines, anticholinergic drugs, glucocorticoids, sodium cromoglycate and ketotifen are critically discussed. Great importance was attached to an adequate selection of one of these drugs or a combination of them with respect to the individual severity of the disease. For typical clinical situations a strategy of long-term treatment is recommended.

Adrenal Cortex Hormones↗
PubMed1982

[Effects of long-term ventilation on the bronchial system. Bronchoscopic, cytologic and microbiological findings].

UNLABELLED: The effects of longterm ventilation were evaluated in 50 patients from a medical intensive care unit. The bronchial tract was investigated using repeated bronchoscopy and assessed by semiquantitative scoring. Prior to each endoscopy tracheal secretions were obtained for microbiological and cytological evaluation, in 20 patients histological analysis of the bronchial mucosa was done in addition. RESULTS: 1. Within 24-48 hours after initiation of respirator ventilation alterations of the bronchial mucosa occur. The extent progresses rapidly, however no further increase of progression is to be observed after ventilation of approximately 150-200 hours. 2. Endoscopic assessment of the severity of mucosal changes correlates well with cytological and histologic results. 3. In 34 patients microbial agents could be demonstrated. In 8 of them mucosal changes preceded demonstration of microbial organisms. The extent of mucosal changes is independent of category or count of pathogen. Endoscopic follow-up investigations of the bronchial tract affected by long-term ventilation serve both direct bronchial clearing and control of position of the intubation tube as well as assessment of mucosal alterations and control of treatment of bronchial infection.

Adolescent↗
PubMed1980

Value and limits of Graham's law for prediction of diffusivities of gases in gas mixtures.

The validity of Graham's law, i.e. the inversely proportional relationship between diffusivity (diffusion coefficient) and the square root of the molecular mass, is tested for test gases and gas mixtures of physiological interest based on recent measurements of diffusivities of gases in gas phase. With gases of medium molecular mass (10 to 30 g/mol) predictions on the basis of Graham's law are reasonably accurate, deviations from experimental values not exceeding 20%. With gases of high and low molecular masses, however, larger discrepancies are encountered. The prediction of diffusion coefficients on the basis of the Chapman-Enskog theory is in most cases more accurate than that based on Graham's law.

Diffusion↗
PubMed1978

Determination of binary diffusion coefficients of various gas species used in respiratory physiology.

In order to provide data required for quantitative analysis of gas diffusion in lung airways, diffusion of He, CO, O2, CO2 and SF6 in various gases used in respiratory physiology was studied in vitro at 37 degrees C and 25 degrees C. The gases were allowed to mix by diffusion in a closed cylindrical tube (length 2 m, internal diameter 1 cm), one half of which was initially filled with 1% test gas in a second gas and the other half of which was filled with the second gas only. Kinetics of diffusional equilibration was determined by withdrawal of spot samples analyzed by gas chromatography. The binary (mutual) diffusion coefficients (D) computed there from were in most cases in good agreement with values calculated on the basis of the Chapman-Enskog theory.

Diffusion↗