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Background
The efficacy of dexamethasone in extending the duration of local anaesthetic block is uncertain. In a randomised controlled triple blind crossover study in volunteers, we tested the hypothesis that neither i.v. nor perineurally administered dexamethasone prolongs the sensory block achieved with ropivacaine.Methods
Ultrasound-guided ulnar nerve blocks (ropivacaine 0.75% wt/vol, 3 ml, with saline 1 ml with or without dexamethasone 4 mg) were performed on three occasions in 24 male volunteers along with an i.v. injection of saline 1 ml with or without dexamethasone 4 mg. The combinations of saline and dexamethasone were as follows: control group, perineural and i.v. saline; perineural group, perineural dexamethasone and i.v. saline; i.v. group, perineural saline and i.v. dexamethasone. Sensory block was measured using a VAS in response to pinprick testing. The duration of sensory block was the primary outcome and time to onset of sensory block the secondary outcome.Results
All 24 subjects completed the trial. The median [inter-quartile range (IQR)] duration of sensory block was 6.87 (5.85–7.62) h in the control group, 7.37 (5.78–7.93) h in the perineural group and 7.37 (6.10–7.97) h in the i.v. group (P=0.61). There was also no significant difference in block onset time between the three groups.Conclusion
Dexamethasone 4 mg has no clinically relevant effect on the duration of sensory block provided by ropivacaine applied to the ulnar nerve.Clinical trial registration
DRKS, 00014604; EudraCT, 2018-001221-98. 相似文献Main outcome measures In all subjects expiratory volumes were determined and urinary analysis was conducted for hydroxyproline, calcium, phosphorus, and cortisol levels. Osteocalcin, calcium, phosphorus, cortisol, alkaline phosphatase, and γ-glutamyltransferase levels were measured in blood samples. Bone density of the lumbar spine was determined by means of dual-energy x-ray absorptiometry. Nutrition evaluation was based on a 3-day food diary analyzed using progiciel Nutri 91. The nutritional parameters examined were calcium; phosphorus; magnesium; zinc; vitamins A, C, and D; protein; total fiber; oxalates; energy; caffeine; and alcohol in relation to bone density.
Subjects Thirty-one patients with moderate to severe asthma who had been taking more than 1,000 μg beclomethasone per day or the equivalent for more than 2 years and 27 patients with mild asthma who were taking less than 500 μg beclomethasone per day or the equivalent.
Statistical analyses performed Four factor analysis of variance with hierarchized interactions of four levels, Duncan's test, Pearson correlation coefficients.
Results Blood levels of osteocalcin and protein intake were lower in patients with moderate to severe asthma than in those with mild asthma (P<.05). Significant correlations (P<.02) were observed between bone density and calcium intake (r=.40), phosphorus intake (r=.35), protein intake (r=.30), and serum alkaline phosphatase level (r=−.30). Bone density was not significantly different between the two groups of patients with asthma.
Applications A follow-up of patients with asthma who are taking inhaled corticosteroids is needed to assess bone density, osteocalcin levels, and dietary intakes of calcium. Verify if osteocalcin level decreases over time in patients with moderate to severe asthma, monitor possible modifications in bone density, and verify if the correlation between dietary calcium and bone density is maintained. J Am Diet Assoc. 1997;97:1401–1406. 相似文献