Effects of granisetron on pruritus, nausea, and vomiting induced by intrathecal opioid in cesarean section under spinal anesthesia

Fentanyl is commonly used for spinal analgesia during labor, but
it is associated with h
igh incidence of pruritus. This
study was performed to evaluate the effect of
intravenous injection of prophylactic granisetron on the
incidence and severity of pruritus induced by
intrathecal fentanyl among
the
parturient
s
undergoing cesarean section under spinal anesthesia.
Materials and methods:
This double
-
blind clinical trial was performed
i
n 136 ASA I or II
(based on the American Society of Anesthesiology
Classification) women undergoing elective
caesarean section under spinal anesthesia with 0.5% hyperbaric bupivacaine (10 mg) and fentanyl (25
μg). After parturition and clamping of the umbi
lical cord,
the subjects
were randomized to receive 1
mg of IV granisetron (group G) or 0.9% saline (group S). To compare the incidence and severity of
pruritus between the two groups, Fisher’s exact test and t
-
test were performed, respectively, using
SPSS
version 21.
Results:
The overall incidence of pruritus was
3.74
%
(group S=
5.76
% and group G=
1.72
%). In
the G group, the incidence of pruritus was significantly different and lower in recovery (P=0.01). There
were significant differences between the groups
in terms of severity of pruritus during surgery
, which
was
lower in the G group (P=0.005).
Conclusion:
This study showed that granisetron as the 5
-
hydroxytryptamine (serotonin) subtype
3 antagonists may reduce the incidence and severity of pruritus induce
d by intrathecal opioid