Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0242706 (hyperoxia)
 5,219 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Values for local cerebral blood flow (LCBF) were measured in three dimensions utilizing xenon enhanced computerized tomography among patients during spontaneously occurring cluster headaches, during headache-free intervals and immediately after terminating attacks by inhalation of 100% oxygen. Results were compared with values measured among age-matched normal volunteers. LCBF values measured in five cluster patients while headache-free did not differ from similar measures among age-matched normal volunteers. In three patients during attacks of spontaneously occurring cluster headache, LCBF values for temporal cortex, basal ganglia and subcortical white matter were increased. Immediately after terminating attacks of cluster by 100% oxygen inhalation for five minutes, LCBF values for temporal cortex and basal ganglia became significantly decreased below normal values in five patients with spontaneously occurring cluster headache. Prompt relief of head pain by inhalation of 100% oxygen is associated with abolition of the hyperperfusion of both cortical and subcortical brain structures that occurs during spontaneously occurring cluster headaches and is followed by excessive cerebrovascular constriction. It remains to be determined whether the cerebral hyperemia occurring during cluster headaches is causally related to the head pain or is secondary to the pain itself. Rapid termination of head pain by hyperoxia associated with excessive cerebral vasoconstriction suggests that this vascular phenomenon is unique to cluster headache and offers clues to its pathogenesis.
 ...
PMID:Cerebral hyperemia during spontaneous cluster headaches with excessive cerebral vasoconstriction to hyperoxia. 205 May 16

To test the influence of arterial O2 saturation (SaO2) on heart rate in cluster headache, changes in pulse rate induced by hyperoxia and hypoxia were monitored in 11 cluster headache patients (6 during cluster period, and 5 during remission). The results were compared with those obtained in 11 age and sex matched healthy individuals. The subjects were administered 5 min each of 100% O2 and 12% O2 in nitrogen in sequence. The aim of the latter procedure was to reduce SaO2 to approximately 80%. Pulse rate was recorded every minute from a finger pulse oximeter during the whole procedure. Cluster headache patients, in particular during the bout, had a slightly lower basal pulse rate than controls (P > 0.5, Student's t-test). This tendency was maintained throughout the test. Hyperoxia and hypoxia resulted in a marked, significant decrease and increase, respectively, in pulse rate from baseline values within each group. However, the difference between groups was not significant at any stage. Cluster headache patients therefore seem to have the same heart rate response to changes in SaO2 as healthy individuals. The marked heart rate changes which sometimes accompany cluster headache are unlikely to be caused by SaO2 changes.
 ...
PMID:Cluster headache: pulse rate changes evoked by hyperoxia and hypoxia. 816 70