Background An addition of analgesic to anesthetic agents is likely to increase the effects of anesthesia and reduce associated adverse outcomes. Several adjuvants are studied in this regard. The aim of this study is to investigate the effects of adding a magnesium adjunct to lidocaine for the induction of infraclavicular block.

Methods Patients referred to Shohada Ashayer Hospital, Khorramabad, for wrist and hand surgery were enrolled in this study. The intervention/case group included patients who received 18 mL lidocaine (2%) + 2 mL magnesium sulfate (50%), 10 mL normal saline; control group: 18 mL lidocaine (2%) + 12 mL of normal saline. After the induction of ultrasound-guided infraclavicular block, parameters such as duration of reach with respect to complete sensory and motor block, hemodynamic parameters (hypotension and bradycardia), and postoperative pain, using visual analogue scale criteria, were measured. The obtained data were analyzed using a Bayesian path analysis model.

Results A total of 30 patients were included in each group. In the case group, sensory and motor block was achieved for 12.136 ± 4.96 and 13 ± 3.589 minutes more than those in the control group. The duration of sedation and immobilization was 2.57 ± 0.764 minute and 4.66 ± 0.909 minutes lengthier in the case group. Regarding the hemodynamic parameters, blood pressure was 0.217 ± 5.031 and 1.59 ± 5.14 units lower in the case group, immediately following the block and the surgery. Similarly, heart rate was 0.776 ± 4.548 and 0.39 ± 3.987 units higher in the case group, after 30 minutes and 2 hours of the procedure. A decrease in the pain was seen at 8, 10, and 12 hours after the surgery, as compared with the control group. An addition of magnesium to lidocaine for infraclavicular block resulted in a significantly longer sedation and immobilization period and decreased postoperative pain at 12 hours.

Conclusion Heart rate and blood pressure did not decrease significantly in the case group. It can be concluded that addition of magnesium sulfate to lidocaine can produce better anesthetic and analgesic outcomes with low-to-no adverse effects.

All relevant data and materials are provided with in the manuscript.

S. B. conceptualized and designed the study, drafted the initial manuscript, and reviewed and revised the manuscript. M. H. S. designed the data collection instruments, collected data, performed the initial analyses, and reviewed and revised the manuscript. A. K. and M. B. B. coordinated and supervised the data collection and critically reviewed the manuscript for important intellectual content. All authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work.

Received: 30 September 2019

Accepted: 30 June 2020

Publication Date:
06 November 2020 (online)

© 2020. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/)

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany