Peter Marhofer1, Malachy Columb2, Phil M Hopkins3, Manfred Greher4, Daniela Marhofer5, Max Bienzle6, Markus Zeitlinger6. 1. Department of Anaesthesia, Intensive Care Medicine and Pain Medicine, Medical University of Vienna, Vienna, Austria. Electronic address: peter.marhofer@meduniwien.ac.at. 2. Department of Anaesthesia, Manchester University Hospitals Foundation Trust, Wythenshawe, UK. 3. Leeds Institute of Medical Research at St James's, University of Leeds, Leeds, UK. 4. Department of Anaesthesia, Intensive Care Medicine and Pain Therapy, Herz Jesu Hospital Vienna, Vienna, Austria. 5. Department of Anaesthesia, Intensive Care Medicine and Pain Medicine, Medical University of Vienna, Vienna, Austria. 6. Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.
Abstract
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 ani.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.
RCT Entities:
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.