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《英国医生杂志》
In Turkey, 19 patients who were admitted with nausea, vomiting, fainting, bradycardia, and hypotension had ingested 30-180 g honey several hours previously as a folk remedy for dyspepsia. Apparently Turkish bees are fond of rhododendrons as a source of nectar. Some species of this plant contain grayanotoxin, the cause of the unpleasant symptoms. The toxin binds to cell membrane sodium channels, provoking prolonged depolarisation with resulting enhanced access for calcium. The authors warn that honey poisoning might occur outside Turkey because of an increase in the consumption of imported, unprocessed honey. The diagnosis should be considered in patients with unexplained acute hypotension, bradycardia, or complete atrioventricular block.
Emerg Med J 2004;21: 742-4
Standard tests do not predict in-flight problems for people with lung disease
Patients with interstitial lung disease or chronic obstructive airways disease may be at risk when flying, despite satisfying current fitness to fly guidelines. Twenty five people volunteered to have arterial blood gas measurements at rest while breathing air or 15% oxygen (to simulate conditions in an aircraft). A third sample was taken after brief minor treadmill exercise to simulate walking around the cabin. Only eight participants were able to complete all phases of the test because their oxygen saturation fell below the predetermined end point of 80%. The results show that the degree of hypoxaemia under simulated aircraft cabin conditions cannot be predicted by resting measurements. None of the participants had experienced untoward symptoms while flying, however, and this is presumably also true of the large number of patients with chronic obstructive pulmonary disease who fly. The question remains open as to when and on whom simulated altitude testing should be performed.
Thorax 2004;59: 966-70
Excessive belching is not mere aerophagia
Patients with excessive belching did not swallow more air than controls nor experience more mixed or liquid reflux in response to a meal of hamburger, chips (fries), onions, and orange juice. They shared with controls the same degree of gas reflux from the stomach, when investigated with manometry, electrical impedance, and pH monitoring. However, researchers from the Netherlands have detected a type of gas reflux unique to excessive belchers, explicable only by oesophageal air ingestion followed by immediate expulsion—without the air ever reaching the stomach. This explains the lack of response to lower oesophageal sphincter relaxation inhibitors such as baclofen. They suspect that excessive belching is learned behaviour, initially induced consciously but eventually becoming automatic.
Gut 2004;53: 1561-5
Childhood asthma is getting less severe
Since 1990 hospital admissions of children for asthma and wheezing have declined from over 65 000 annually to fewer than 38 000. This mirrors observations of a decline in asthma morbidity in primary care. The prescription of "prevention" inhalers (overwhelmingly inhaled corticosteroids) has also risen steadily, so perhaps this is cause and effect rather than simple association.
Arch Dis Child 2004;89: 1158-60
If the honey doesn't get you, the bees will
A 57 year old woman was stung by 30-40 African honey bees (killer bees) and appropriately treated with antihistamines. Two days later she reported visual field loss, became unresponsive, then developed vomiting and neck rigidity. Computed tomography of the head and magnetic resonance imaging of the brain showed a large right temporo-occipital infarct. She developed bilateral optic neuropathy and was left with a marked field defect. The mechanism is probably immune mediated vasoconstriction in response to bee venom and a consequent prothromobotic state.
Br J Ophthalmol 2004;88: 1596-8(Honey can be cardiotoxic)
Emerg Med J 2004;21: 742-4
Standard tests do not predict in-flight problems for people with lung disease
Patients with interstitial lung disease or chronic obstructive airways disease may be at risk when flying, despite satisfying current fitness to fly guidelines. Twenty five people volunteered to have arterial blood gas measurements at rest while breathing air or 15% oxygen (to simulate conditions in an aircraft). A third sample was taken after brief minor treadmill exercise to simulate walking around the cabin. Only eight participants were able to complete all phases of the test because their oxygen saturation fell below the predetermined end point of 80%. The results show that the degree of hypoxaemia under simulated aircraft cabin conditions cannot be predicted by resting measurements. None of the participants had experienced untoward symptoms while flying, however, and this is presumably also true of the large number of patients with chronic obstructive pulmonary disease who fly. The question remains open as to when and on whom simulated altitude testing should be performed.
Thorax 2004;59: 966-70
Excessive belching is not mere aerophagia
Patients with excessive belching did not swallow more air than controls nor experience more mixed or liquid reflux in response to a meal of hamburger, chips (fries), onions, and orange juice. They shared with controls the same degree of gas reflux from the stomach, when investigated with manometry, electrical impedance, and pH monitoring. However, researchers from the Netherlands have detected a type of gas reflux unique to excessive belchers, explicable only by oesophageal air ingestion followed by immediate expulsion—without the air ever reaching the stomach. This explains the lack of response to lower oesophageal sphincter relaxation inhibitors such as baclofen. They suspect that excessive belching is learned behaviour, initially induced consciously but eventually becoming automatic.
Gut 2004;53: 1561-5
Childhood asthma is getting less severe
Since 1990 hospital admissions of children for asthma and wheezing have declined from over 65 000 annually to fewer than 38 000. This mirrors observations of a decline in asthma morbidity in primary care. The prescription of "prevention" inhalers (overwhelmingly inhaled corticosteroids) has also risen steadily, so perhaps this is cause and effect rather than simple association.
Arch Dis Child 2004;89: 1158-60
If the honey doesn't get you, the bees will
A 57 year old woman was stung by 30-40 African honey bees (killer bees) and appropriately treated with antihistamines. Two days later she reported visual field loss, became unresponsive, then developed vomiting and neck rigidity. Computed tomography of the head and magnetic resonance imaging of the brain showed a large right temporo-occipital infarct. She developed bilateral optic neuropathy and was left with a marked field defect. The mechanism is probably immune mediated vasoconstriction in response to bee venom and a consequent prothromobotic state.
Br J Ophthalmol 2004;88: 1596-8(Honey can be cardiotoxic)