Comparative study between intravenous versus perineural dexamethasone in prolonging the analgesic effect of supraclavicular plexus nerve block in hand surgeries

Abstract

Background: Poorly controlled acute pain after surgery is associated with a variety of unwanted postoperative consequences, including patient suffering, distress, myocardial ischemia, prolonged hospital stays and an increased likelihood of chronic pain. Systemic analgesics (opioids and non-opioids) have long been used for postoperative pain, then neuroaxial or peripheral nerve blocks were employed. Local anesthetics alone were used, then various adjuvants were added to achieve quick, dense and prolonged block. Objective: To study the effect of dexamethasone as an adjuvant to bupivacaine either intravenous or perineural in ultrasound guided supraclavicular brachial plexus block in hand surgeries regarding the onset of the block, the duration of the block, the effect on postoperative analgesic requirements as well as anticipated complications. Patients and Methods: In our study, 50 patients were randomly divided into 2 equal groups. perineural group received bupivacaine (0.5%) concomitant with 8 mg dexamethasone and Systemic group in which 8 mg of dexamethasone were injected systemically. All patients received equal volumes of 20 milliliters. Results: Our study showed that addition of a8 milligram of dexamethasone to bupivacaine in ultrasound-guided supraclavicular nerve block shortened the onset times of sensory and motor blocks and significantly prolonged their durations. In addition, dexamethasone prolonged the duration of analgesia of the plexus block significantly, as proved by the time of request of first analgesia. Moreover, in perineural dexamethasone group, postoperative analgesic requirements were greatly lesser than that of bupivacaine groups. Addition of dexamethasone perineural also did not affect the hemodynamics to a significant level. This makes perineural dexamethasone with bupivacaine more superior than the use of bupivacaine with addition of intravenous dexamethasone. Conclusion: The use of ultrasonography in performing the supraclavicular nerve block, decreased significantly the incidence of complications such as pneumothorax or intravascular injection and hence, lowered the incidence of systemic toxicity of local anesthetics.