Effect of adding dexamethasone to intrathecal bupivacaine on blood sugar of controlled diabetic patients undergoing diabetic foot surgeries

Background Spinal anesthesia is acceptable in patients undergoing diabetic foot surgery. The duration of the spinal anesthesia has been improved by the addition of other drugs such as opioids, dexmedetomidine, clonidine, and dexamethasone. Dexamethasone may affect blood glucose levels. The primary outcome of the study was the effect of a single dose of intrathecal dexamethasone on blood glucose levels during the first 24 h postoperatively. Patients and methods After approval, 60 diabetic patients, American Society of Anesthesiologists grades 2 and 3 with ages ranging from 20 to 70 years were enrolled in this randomized, double-blinded, placebo-controlled trial. All patients who underwent diabetic foot surgery under spinal anesthesia have controlled type II diabetes. Patients were randomly allocated into two equal groups: the control group was given intrathecal 2.5 ml of hyperbaric bupivacaine 0.5% plus 1 ml of 0.9% sodium chloride. The dexamethasone group was given intrathecal 2.5 ml of hyperbaric bupivacaine 0.5% plus 4 mg of dexamethasone. Results The control group had significantly lower levels of blood sugar at different times compared with the dexamethasone group. However, at the end of 24 h, nonsignificant changes were present between the two groups. Also, using 200 mg/dl as a cutoff for high blood sugar, there were nonsignificant changes all through the 24 h in both groups. Moreover, dexamethasone prolongs the duration of analgesia and decreases paracetamol requirements during the first 24 h postoperatively. Conclusions Addition of intrathecal dexamethasone did not change postoperative glycemic evolution in controlled diabetic patients undergoing diabetic foot surgery. However, it significantly prolongs the duration of analgesia and decreases analgesic consumption during the first 24 h postoperatively.