the effect of subcutaneous dexamethasone added to bupivacaine on postcesarean pain: a randomized controlled trial

background: previous studies have shown a prolonged blockade of nerves using bupivacaine-dexamethasone microspheres. the goal of this study was to assess the effect of subcutaneous dexamethasone added to bupivacaine on post cesarean pain.   methods: after randomization, 75 healthy parturients were allocated into three groups and received the following treatments: group a: bupivacaine 0.25% (20 ml, subcutaneously [s.c]) plus dexamethasone 16 mg (4 ml, s.c) plus normal saline (4 ml, intravenously [i.v]); group b: bupivacaine 0.25% (20 ml, s.c) plus dexamethasone 16 mg (4 ml, i.v) plus normal saline (4 ml, i.v); group c: bupivacaine 0.25% (20 ml, s.c) plus normal saline (4 ml, s.c) plus normal saline (4 ml, i.v). the visual analog scale (vas), meperidine consumption, and time to first meperidine consumption were evaluated in the recovery room, 6, 12, 24, 48, and 72 hours postoperatively.   results: the mean vas in group a was less than groups b and c at 12, 24 , 48 and 72 hours after surgery (a< c< b respectively). the decrease in vas was statistically significant between group s a, b and b, c (p=0.009 and p=0.015 respectively). the mean vas in group a was significantly less than group c at 48 and 72 hours postoperatively (p=0.020 and p=0.024 respectively). meperidine consumption was lower in group a compared with b and c groups, however it was not statistically significant (p=0.25 and p=0.11 respectively).   conclusion: the addition of subcutaneous dexamethasone to bupivacaine prolonged the analgesia during 48-72 hours postoperatively. it may be an option for longer pain relief after cesarean section.