Clinical science
-
Randomized Controlled Trial Clinical Trial
Effect of oral digoxin, topical ouabain and salbutamol on transepithelial nasal potential difference in patients with cystic fibrosis.
1. Airway epithelium in cystic fibrosis is characterized by a defect in chloride secretion across the apical membrane and an increase in sodium absorption. The increased rate of sodium absorption can be inhibited in vitro by ouabain, a Na(+)-K(+)-ATPase inhibitor, and in cystic fibrosis patients the number and activity of nasal epithelial Na(+)-K(+)-ATPase pumps is increased. 2. ⋯ In study 1, nasal potential difference measurements were repeated on non-consecutive days in 20 patients with cystic fibrosis and 20 healthy individuals. Healthy subjects had a mean (SEM) potential difference value of -19.5 (0.9) mV with a 95% range for a single estimate of 75-133%. In patients with cystic fibrosis, the mean (SEM) potential difference was -40.4, (2.1) mV, with a 95% range for a single estimate of 74-136%.(ABSTRACT TRUNCATED AT 250 WORDS)
-
Randomized Controlled Trial Clinical Trial
Intracranial pressure at high altitude and acute mountain sickness.
1. Raised intracranial pressure has been noted in severe forms of acute mountain sickness and high-altitude cerebral oedema, but the role of intracranial pressure in the pathogenesis of mild to moderate acute mountain sickness is unknown. 2. ⋯ Acute hypoxia at 3440 m was associated with a rise in intracranial pressure, but no difference was found in pressure changes at 4120 or 5200 m in subjects with or without symptoms of acute mountain sickness. 4. Raised intracranial pressure, though temporarily associated with acute hypoxia, is not a feature of acute mountain sickness with mild or moderate symptoms.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Effects of inhaled nebulized morphine on ventilation and breathlessness during exercise in healthy man.
1. Nebulized inhaled morphine has been reported to increase exercise endurance in patients with chronic lung disease and to relieve dyspnoea in patients with malignant disease. Potential mechanisms include a central effect occurring after systemic drug absorption or a local action mediated by receptors in the lung. 2. ⋯ Intravenous morphine 2.5 mg reduced breathlessness slightly at the highest equivalent workload [mean (least significant range) 33 mm (26-40 mm)] compared with placebo [41 mm (34-48 mm), P < 0.05] but had no other significant effects. 5. These results do not support the hypothesis that intrapulmonary opiate receptors modulate the sensation of breathlessness in healthy man. The possibility that inhaled morphine may affect breathlessness caused by other factors, such as disease, has not been excluded.
-
Randomized Controlled Trial Clinical Trial Controlled Clinical Trial
Augmented thermic effect of amino acids under general anaesthesia: a mechanism useful for prevention of anaesthesia-induced hypothermia.
1. Intravenous infusion of amino acids stimulates energy expenditure and heat accumulation in normal man. To find out whether such stimulation also occurs during general anaesthesia, thermogenesis was measured in 21 patients before, during and after anaesthesia and surgery. 2. ⋯ The difference, 21 W, illustrates the thermogenic action of the amino acids. This value may be compared with that of 4 W, observed in unanaesthetized individuals subjected to 30 min of identical amino acid infusions. 4. At awakening after the anaesthesia, the oxygen consumption rose to 71 +/- 21% above the pre-anaesthesia level in the amino acid-treated patients, who, without shivering, rapidly returned to normothermia, whereas in the control patients the oxygen uptake remained slightly below the pre-anaesthesia level, despite sustained hypothermia and vigorous shivering.(ABSTRACT TRUNCATED AT 250 WORDS)
-
Letter Randomized Controlled Trial Clinical Trial
Dihydroxyphenylglycol and dihydroxymandelic acid during intravenous infusions of noradrenaline.