Biomedical subjects

D J Lipscomb

Publications and source records attributed to D J Lipscomb.

7 recordsLinked to original sources

PubMed1981

Ultrasound of the pleura: an assessment of its clinical value.

In a prospective study, A mode ultrasound scanning contributed to the diagnosis and management of 24 of 50 consecutive patients with pleural disease. In 30% of patients it was superior to radiology in clarifying the solid or fluid nature of a pleural opacity, and in 42% of patients it allowed selection of the most appropriate site for the aspiration of pleural fluid. The technique is simple and the apparatus is widely available. We believe that ultrasound is an important practical aid in the diagnosis and management of pleural disease.

Humans↗

PubMed1980

Baclofen overdose.

A 57-year-old woman suffering from multiple sclerosis took an estimated 1500 mg of baclofen. She became deeply unconscious with generalized flaccid muscle paralysis and absent tendon reflexes. Toxicological analysis confirmed the presence of baclofen together with small amounts of paracetamol and glutethimide. Supportive therapy, including assisted ventilation for 3 days, led to complete recovery; anticonvulsant drugs were necessary for the treatment of grand mal fits. The clinical features and treatment of baclofen overdose are discussed.

Baclofen↗

PubMed1980

Ultrasound in the diagnosis and management of pleural disease.

A-mode ultrasound investigation has been performed in 62 patients, of whom 35 presented problems of diagnosis and management of pleural disease. In seven patients with known pleural effusion in whom aspiration had failed ultrasound correctly identified fluid at a site different from the aspiration attempts and in all seven cases it weas successfully removed. The remaining 28 patients had the radiographic appearances of localized pleural disease and ultrasound correctly distinguished fluid and solid lesions in 26. We found ultrasound to be a simple and reliable technique which was particularly valuable in locating fluid for aspiration and in distinguishing between fluid and pleural thickening. The simplicity and 'bedside' availability of ultrasound offered certain practical advantages over radiography.

Adult↗

PubMed1980

A computer simulation of physiological factors contributing to hyperventilation and breathlessness in cardiac patients.

A computer model of human respiration is of value for teaching the basic principles of respiratory physiology to students. An extension of this educational use is in the theoretical exploration of the relative importance of individual factors which may be contributing to disordered function in common clinical problems. For example, when a cardiac patient becomes breathless with increase in ventilation during exercise there are alterations in many physiological variables. The influence of their individual contributions on the total ventilation and thence possibly on breathlessness is often difficult to estimate. We present a theoretical analysis using MACPUF, a digital computer simulation of circulation and gas exchange which can be used to extimate the quantitative contribution of relevant physiological variables by altering them singly and in combination. Alterations in dead space, physiological shunt and pulmonary compliance individually produce only small increases in ventilation. Increased neurogenic drive (e.g. from lung reflexes triggered by pulmonary congestion) is a potentially important but very variable factor. A more important influence on ventilation appears when cardiac output is reduced and anaerobic metabolism simulated, causing changes in blood gas tensions and acidaemia which then change ventilation. Any increase in ventilation becomes more significant as a cause of breathlessness when ventilatory capacity is reduced, which in cardiac patients it not infrequently is.

Cardiac Output↗

PubMed1978

Interpretation of increases in the transfer coefficient for carbon monoxide (TLCO/VA or KCO).

During a 15-month period, 27 patients were seen in a routine clinical pulmonary function laboratory in whom the transfer coefficient (TLCO/VA or KCO), measured by the single breath technique, was increased. Pulmonary haemorrhage accounted for two-thirds of the cases; in them sequential measurements of KCO were able to monitor the onset and cessation of bleeding. In the remaining cases the cause of the increase in KCO remains uncertain. All patients had a reduction in vital capacity. Experiments in six normal subjects showed that KCO rose as the breath-holding lung volume was reduced, but that this was insufficient to account for the raised KCO in patients with reduced volumes. Partitioning of the two components of TLCO at different lung volumes in three normal subjects showed that an increase in pulmonary capillary blood volume per unit alveolar volume was chiefly responsible for the increase of KCO in normal subjects at lower lung volumes. The membrane diffusing capacity changed less than predicted per unit volume, suggesting that the thickness of the air-blood barrier remains fairly constant as the lung expands or contracts.

Adult↗

PubMed1977

Ventilation and perfusion scans in the preoperative assessment of bronchial carcinoma.

Ventilation (krypton -81m) and perfusion (technetium -99m) lung scans were obtained in a consecutive series of 21 patients shortly before thoracotomy for proven or suspected carcinoma of the bronchus. In most patients ventilation and perfusion were impaired equally and the scan abnormality corresponded to the bronchoscopic and radiological findings. Unexpectedly large defects in the perfusion scan were seen in three patients, all of whom had extensive neoplastic involvement of the mediastinum at thoracotomy, but 11 other patients had mediastinal involvement which was not suspected from the scan. Ventilation scanning was useful in the prediction of postoperative ventilatory capacity in two patients who underwent pneumonectomy. We conclude that ventilation and perfusion scans are not sensitive indicators of neoplastic involvement of the mediastinum but they are valuable for the prediction of postoperative lung function.

Adult↗

PubMed1975

Studies with activated charcoal in the treatment of drug overdosage using the pig as an animal model.

Pigs were given large oral doses of paracetamol, amylobarbitone and amitriptyline. The effect of administering activated charcoal at varying intervals after dosing on the blood drug-level profiles of paracetamol and amylobarbitone was assessed by comparison with the profiles obtained when charcoal therapy was withheld. An appreciable effect on paracetamol absorption was demonstrated when charcoal was given up to 1 h after dosing. The amylobarbitone-dosed pigs exhibited delayed gastro-intestinal absorption of drug and this was substantially reduced by activated charcoal given 4 hrs after dosing. The pigs metabolised amitriptyline at too high a rate for meaningful studies to be undertaken with this drug.

Acetaminophen↗