Biomedical subjects
Karl Bjørnar Alstadhaug
Publications and source records attributed to Karl Bjørnar Alstadhaug.
[Occurrence of multiple sclerosis in Nordland, 1970-1999].
BACKGROUND: Epidemiologic data for multiple sclerosis in Nordland County in Norway has not been recorded for more than 50 years. MATERIAL AND METHODS: Cases between 1970 and 1999 were identified by diagnostic code searches in the files of Nordland Central Hospital, the county's only hospital with a department of neurology. Several cases from Nordland were also identified in hospital files in neighbouring counties. RESULTS: The raw prevalence of multiple sclerosis was determined to be 105.6 per 100,000 as at December 31, 1999. The crude annual incidence in the 1970-1999 period was 3.6 per 100,000 (95 % CI: 3.1-4.0). There was a pronounced rise in incidence from the late 1970s up until the early 1980s. From 1985 to 1999, the average annual incidence rate has been stable at 5.1 per 100,000 (95 % CI: 4.4-5.8). INTERPRETATION: Compared to other Norwegian counties for which there are epidemiologic data, Nordland represents a medium risk zone for multiple sclerosis. The increase in incidence from the late 1970s to the early 1980s is most likely due to improved diagnosis and better record-keeping.
[A 71-year-old man with Cushing reflex].
BACKGROUND: The Cushing reflex in comatose intensive care patients usually indicates that intracranial perfusion is about to be abolished. MATERIAL AND METHODS: A 71-year-old man suffered an attack during which he became comatose. After 14 hours he developed polyuria, dilated fixed pupils and Cushing reflex. The cause was believed to be a global anoxic brain oedema. Coma, apnoea and absent brain stem reflexes suggested brain death. RESULTS: Angiography with contrast injected into the aortic arch showed preserved circulation in both internal carotid, middle and anterior cerebral arteries, but absence of basilar artery circulation. A cerebral CT scan was initially normal, but 14 hours later a new scan demonstrated infarction of the brain stem, cerebellum and occipital lobes. The Norwegian criteria for organ donation were not fulfilled as these require stop of all intracranial circulation. The respirator was disconnected and the patient died. INTERPRETATION: The Cushing reflex can be seen after profound ischaemia in the posterior cerebral circulation with preserved circulation to the forebrain. Ischaemia of the brain stem alone may be sufficient to elicit the Cushing reflex.