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Biomedical subjects

M Andersen

Publications and source records attributed to M Andersen.

At least 181 records · Page 10Linked to original sources

Preoperative starvation and blood glucose concentrations in children undergoing inpatient and outpatient anaesthesia.

Blood glucose concentrations were measured in 82 children undergoing inpatient anaesthesia and in 46 children undergoing anaesthesia as outpatients. The children were aged between 6 months and 9 yr. Outpatients were fasted from bedtime, while inpatients were randomly allocated to two groups. In group A the children were fasted from bedtime, whereas in group B the children were fed 6 h before anaesthesia. There was no difference in mean blood glucose concentration between the fasted inpatients and outpatients nor between children younger than, or older than, 4 years of age. A blood glucose concentration of less than 40 mg dl-1 was found in only one of the fasted children (1%). The mean blood glucose concentration was greater in group B than A, but only significantly so for children older than 4 yr. It is concluded that to minimize the risks of hypoglycaemia and inhalation of vomit on induction of anaesthesia children older than 6 months should be fasted overnight and operated on in the morning.

Ambulatory Surgical Procedures↗

Continuous registration of blood velocity and cardiac output with a hot-film anemometer probe, mounted on a Swan-Ganz thermodilution catheter.

In order to construct a catheter, capable of monitoring cardiac output, a specially designed double-conical hot-film anemometer probe was fastened at the tip of a Swan-Ganz thermodilution catheter. Common sources of error for most catheter velocity probes include difficult calibration, unknown velocity profile at the point of measurement and unknown position of the probe in this profile. By using mongrel dogs and in order to exclude these sources of error, the intermittent thermodilution method was used to in vitro calibrate the hot-film anemometer, which registered velocity continuously. A mean correlation coefficient between these two methods was found to be 0.886. A mean line of regression between thermodilution (abscissa) and anemometer (ordinate) had a slope of 0.796 +/- 0.223 (+/- SD) and a y-intercept of 24 +/- 14 ml/min/kg. The slope was significantly lower than one (t test, p less than 0.05) and the y-intercept significantly larger than zero (t test, p less than 0.02). As a control of the thermodilution method, electromagnetic flow in the ascending aorta was registered and a mean correlation coefficient of 0.967 found. The hot-film sensor itself can be used as thermodilution method with the hot-film anemometer's continuous registration of velocity.

Animals↗

Mutagenic action of isocyanates used in the production of polyurethanes.

Isocyanates used in the production of polyurethanes were investigated for mutagenic action in Salmonella typhimurium. These investigations showed that the most commonly used isocyanates, toluene diisocyanate (TDI) and 4,4'-methylene-diphenylisocyanate (MDI), are mutagenic. This effect can be ascribed to the amine analogues formed during the hydrolysis of isocyanates: TDI is mutagenic in TA 1538 and TA 98 after metabolic activation. This finding agrees with the results obtained with the amine analogue 2,4-toluenediamine. MDI, like the amine analogue 4,4'-methylenedianiline, is mutagenic in TA 100 after metabolic activation by rat liver enzymes (S-9 mix). A prepolymerized polyisocyanate of the MDI type is also mutagenic in assays using TA 100 and S-9 mix. It is concluded that isocyanates are potentially mutagenic and carcinogenic to man. In view of their widespread use in the work environment and in light of the high production figures for polyurethanes in industrialized countries, isocyanates must be considered to represent a serious health hazard.

Cyanates↗

Clinical and laboratory findings in patients subjected to laparotomy for suspected acute appendicitis.

In a retrospective study, clinical and laboratory findings in 454 patients subjected to laparotomy for suspected acute appendicitis were evaluated. A normal appendix was found in 25% of the total series and was twice as common in female as in male patients. Perforated appendicitis was present in 8% of the series, most commonly in the youngest (less than 5 years) and the oldest (greater than 40 years) age groups. The incidence of severe appendicitis increased with the duration of the preoperative abdominal symptoms. Of the patients with a 'laboratory profile' including fever and leukocytosis, 44% had gangrenous or perferated appendicitis. Of those who additionally had elevated ESR (greater than 20 mm), 62% showed a gangernous or perforated appendicitis. The overall incidence of wound infection was 13.9%. Wound infection was closely related to the state of the appendix. The results thus indicated that patient's age, duration of abdominal symptoms and the 'laboratory profile' are important parameters for assessment of clinically suspected acute appendicitis.

Acute Disease↗

Obstetric practice amongst Queensland general practitioners: a survey of needs and attitudes.

A survey of Queensland general practitioners was carried out to assess their needs and attitudes regarding obstetric practice. Less than half of the respondents now practise obstetrics, and many general practitioners felt a lack of support from specialist obstetricians, paediatricians, and anaesthetists. Many of the respondents expressed needs for further obstetric training, especially in labour ward management and neonatal care; however, few were able to attend extended courses.

Adult↗

Thyroid replacement therapy in Down's syndrome with hypothyroidism.

Three elderly subjects with Down's syndrome and biochemical evidence of hypothyroidism were investigated before and after four months of thyroid replacement treatment. The patients' appearance was demonstrated by photographs and the biochemical thyroid values and the intellectual performance were assessed. The appearance before treatment varied from a florid myxoedematous appearance to a state without features indicating myxoedema. Thyroid replacement therapy was given in usual dose and the biochemical response was similar to that seen in normal subjects. The intellectual performance improved little or not at all. The characteristic discomfort usually associated with hypothyroidism was very pronounced in one case and disappeared totally during treatment. It is concluded that the diagnosis of hypothyroidism in elderly subjects with Down's syndrome can be very difficult when based on appearance and history alone and biochemical thyroid tests are often necessary. The patients should be treated with replacement therapy just as other patients suffering from hypothyroidism.

Down Syndrome↗