PubMed Health⌕ Search

Biomedical subjects

G Björnsson

Publications and source records attributed to G Björnsson.

7 recordsLinked to original sources
PubMed1987

Sympathetic activity and haemodynamic variables during spinal analgesia in man.

At present there is a lack of information concerning haemodynamic changes related to the degree of sympathetic blockade during spinal analgesia. In this investigation, involving 36 patients, changes in haemodynamic parameters were studied in 30 patients receiving spinal analgesia and in six patients having "sham spinal" analgesia. Three local anaesthetic solutions were used: bupivacaine without and with glucose and tetracaine with glucose. Skin conductance responses were used to evaluate changes in provoked sympathetic activity. It was found, as in previous studies, that a complete block of sympathetic activity in the foot was seen in only 60% of patients with an average analgesic level of T4. A partial sympathetic blockade was registered up to and above the level of analgesia. In 25/30 cases only minor alterations in cardiac output, heart rate, stroke volume, mean arterial pressure and systemic vascular resistance were seen in spinal analgesia whose level reached on average T4-5. In five cases in whom analgesia reached T4-3, mean arterial pressure fell greater than or equal to 30% with a well-preserved cardiac output, but with complete sympathetic blockade up to T5 and in two cases also in the hand. Only minor differences were observed between the different anaesthetic solutions.

Analgesia↗
PubMed1986

The prevalence of open-angle glaucoma in Iceland.

A compilation of all prescriptions issued for glaucoma medication in Iceland for a 6 months period, together with hospital records of all patients operated on for primary open-angle glaucoma but not on glaucoma medication, were analysed for the prevalence and distribution of glaucoma in Iceland. The glaucoma population consisted of 1916 individuals (991 males and 925 females), amounting to an overall prevalence of 8.3 per thousand population. About 80% of the patients were on glaucoma medication and the remaining had been operated on but had not used drugs. Only 2.6% of the glaucoma population was under 50 years of age. The overall prevalence among those aged 50 and older was 35.3 per 1000, all having primary open angle glaucoma (subsuming glaucoma with pseudoexfoliation of the lens capsule). The prevalence increased with age from 5.7 per 1000 at age 50-59, to 107.5 at age 80 and older. Rates for males were significantly higher than rates for females in all age groups. The rates were highest in regions where ophthalmologists visit health centers regularly. Assuming that the open-angle glaucoma patients in Iceland as a whole have a similar eye status to the patients attending the University Outpatient Glaucoma Clinic, the overall prevalence of GVFD (glaucoma visual field defects) in the population aged 50 and older is 19.1 per thousand. The age specific prevalence of GVFD in Iceland is therefore consistent with results of prevalence studies in neighbouring countries.

Adult↗
PubMed1981

Zimelidine to geriatric patients: a pharmacokinetic and clinical study.

To evaluate the clinical efficacy, tolerance and pharmacokinetic properties of zimelidine in elderly people, twelve hospitalized depressed patients with a mean age of 80 years were included in a clinical trial. Zimelidine was administered twice daily at a dose of 50 mg during the first week, 75 mg during the second week and 100 mg during the third to sixty week. The patients also received a single oral test dose of 75 mg of zimelidine during an initial placebo week. All patients that completed the study improved according to the rating scales used. The drug was well tolerated, and adverse reactions were few and of mild or moderate severity. No influence of clinical importance was noted on hematology, liver and kidney functions, ECG, blood pressure or pulse rate. The mean elimination half-lives of zimelidine and norzimelidine were found to be 15 h and 35 h, respectively, which were longer than the half-lives earlier obtained in younger patients. The blood levels (AUC) in the geriatric patients were about twice those obtained earlier in healthy volunteers. The AUC values for both zimelidine and norzimelidine increased in close proportion to the increase in dose and, thus, the pharmacokinetics of zimelidine was apparently not dose-dependent in the dose interval used. The results obtained may indicate a reduction in the rate of metabolism for zimelidine in the elderly, possibly combined with increased total bioavailability of the drug. A reduction of the regular zimelidine dose may be recommended in the treatment of elderly patients.

Aged↗
PubMed1980

Childhood blindness in Iceland. A study of legally blind and partially seeing children in Iceland 1978.

In 1978, a study was made of legally blind (corrected visual acuity 6/60 or less) and partially seeing (CVA 6/18 to 6/60) children under 15 years of age in Iceland. A total of 43 children were found, of whom 23 were legally blind and 20 partially seeing. The prevalence rates, expressed as the number per 100,000, children of similar age, 36.4 for legal blindness and 31.6 for partial sight. In all 43 children, the visual loss was attributable to heritable, congenital, or developmental defects. The most common causes of visual loss were optic nerve atrophy and cataracts. Other causes are listed and discussed. No cases of acquired visual loss were found. In addition to visual loss, other congenital birth defects were found in 24 of the children. CNS affection was found in 20 of the children, and of these, 15 were mentally retarded.

Abnormalities, Multiple↗