Search PubMed⌕ Search

Biomedical subjects

A A Greenfield

Publications and source records attributed to A A Greenfield.

9 recordsLinked to original sources
PubMed1984

Infusion rates for anaesthesia with propofol.

The infusion rate of propofol which would produce anaesthesia, when combined with nitrous oxide in oxygen, was studied in 75 fit unpremedicated patients undergoing body surface operations. The infusion rates were based on multiples of the median dose required to produce anaesthesia by intermittent injection in an additional 20 patients. The scatter of doses showed a right skew, for both intermittent and continuous use. This was corrected by loge transformation and derived data presented graphically.

Adolescent↗
PubMed1984

Declining mortality in the immature: medical or biological effect?

A steady and significant decline in the proportions of liveborn infants who died in the first week from problems associated with immaturity occurred among Sheffield babies born between 1947 and 1979. The decline occurred in all three maternity units, regardless of the availability of neonatal care facilities. The rate of decline in the best equipped and best staffed hospital, however, was significantly greater during the 1970s than would have been predicted from the trend in earlier years and in contrast to the other hospitals. This greater decline shows a closer temporal association with a reorganisation of labour wards and nurseries than with the introduction of advanced equipment but also correlates with an increasing abortion rate among women who would be expected to have premature deliveries. Factors responsible for the secular decline have not been identified, but it is postulated that Sheffield's mothers are bearing healthier children as a result of improvements in maternal health which are themselves a consequence of changes during girlhood.

Birth Weight↗
PubMed1983

Post-thoracotomy pain relief: combined use of cryoprobe and morphine infusion techniques.

In a reported study we found that freezing of the intercostal nerves under direct vision at thoracotomy provided better postoperative analgesia than im morphine on demand. Infusions of morphine were also more effective than when used by the intramuscular route. The benefit on the eighth postoperative day was greatest following the use of the cryoprobe. Further studies were carried out to evaluate the benefit of combining 'cryoprobe' analgesia with infusions of morphine. The combined use of morphine infusion and a cryoprobe did not produce greater postoperative pain relief than the use of the cryoprobe alone with im morphine on demand.

Adult↗
PubMed1982

Laboratory data on ICU admission. Its relationship to mortality.

One hundred and seventeen patients admitted to an intensive care unit were studied, to determine whether there is any relationship between laboratory data taken on admission to the unit and the final outcome (survival or non-survival) of the stay within the intensive care unit. Discriminant analysis of the data shows that patients could be allocated to one of two groups (survival or non-survival) using the two parameters of age and serum phosphate, and that this allocation proves correct in 70% of cases, irrespective of the admitting disease and treatment. The validity of this discriminant function was tested in a further 53 cases and the allocation of patients to survival or non-survival groups was found to be correct in 70% of cases, supporting the first estimate of the discriminant function.

Age Factors↗
PubMed1982

Analysis of HLA antigen association with proliferative diabetic retinopathy.

One hundred and thirteen patients with insulin dependent diabetes mellitus for at least 15 years were typed for 22 HLA antigens of the A and B series. Fifty-six patients had severe bilateral proliferative retinopathy and 57 had no retinopathy. There was no statistical difference in frequency of HLA antigens between the 2 groups of diabetic patients. There was a significantly higher frequency of HLA B15 and a significant lower frequency of HLA B14, B17 in the combined diabetic groups than in a control population of 200 normal blood donors.

Diabetes Mellitus, Type 1↗
PubMed1980

Pharmacodynamic aspects of long-term prophylactic lithium.

In 90 male and female patients suffering from recurrent affective disorders who had been stabilised for long periods on lithium carbonate an investigation was carried out to determine factors influencing the dosage and excretion of lithium. The findings support the view that lithium excretion is largely controlled by osmotic factors and that it is a function of the overall renal efficiency. The dosage requirement is a function of both body surface area and weight which are closely correctly with measures of renal efficiency though there are also age and sex differences which are independent of body size.

Affective Disorders, Psychotic↗
PubMed1977

Lithium therapy and alkaline earth metal metabolism: a biochemical screening study.

A study is described of 90 patients receiving lithium prophylactically for recurrent affective disorder. A total of 90 biochemical variables was analysed by correlation matrices. No abnormality in calcium or magnesium metabolism was detected though this may merely be a reflection of the insensitivity of the screening technique used.

Adult↗
PubMed1973

Discriminant value of thyroid function tests.

Different thyroid function tests permitted a final classification of 204 consecutive patients with suspected thyroid disorders into three populations (thyrotoxic, euthyroid, and hypothyroid). Linear discriminant analysis was applied to all test results (10 variates) on adjacent population pairs. Two invitro tests (serum protein bound iodine (P.B.I.) and tri-iodothyronine (T-3) uptake values) gave good separation of thyrotoxic from euthyroid patients and fairly good distinction of hypothyroid patients. If a (131)I uptake figure was then added to the in-vitro results most patients (95.5%), including thse initially classified as equivocal, were correctly diagnosed. Other tests, including clinical questionnaires, were poor discriminants.Two new techniques of utilizing the test data were devised. Firstly, the data from the two in-vitro tests were also displayed graphically, and oblique boundary lines derived from the discriminant functions gave better separation of patients than previously used limits or mathematical expressions of "free thyroxine." Secondly, a nomogram incorporating the best four discriminants was designed as a diagnostic aid and proved to be the best means of interpreting the tests.Discriminant analysis of this kind can be used in the interpretation of diagnostic tests in any branch of medicine, and it allows the best use to be made of the available data.

Diagnosis, Differential↗