Hyoscine Butyl-bromide Versus Ondansetron for Nausea and Vomiting During Cesarean Section Under Spinal Anesthesia
Status:
Recruiting
Trial end date:
2022-08-01
Target enrollment:
Participant gender:
Summary
overall incidence of intraoperative nausea and vomiting(IONV) during regional anesthesia for
cesarean section is extremely variable, up to 80 percent , depending on the anesthetic
technique used (spinal, epidural or combined spinal-epidural) and on the preventive and
therapeutic measures taken.1 Spinal anesthesia for CS is safe and effective; it is currently
the anesthetic technique of choice for elective Cesarean delivery (CD). However, maternal
hypotension associated with spinal anesthesia is one of the primary causes of intraoperative
nausea and/or vomiting (IONV); this symptom is thought to be caused by cerebral and gut
hypoperfusion that stimulate the vomiting centre in the brainstem and cause serotonin
release, respectively.2, 3 While bolus dosing of phenylephrine effectively treats maternal
hypotension, it does not prevent intraoperative maternal nausea, which may be associated with
established hypotension, and this may adversely affect patient satisfaction.4, 5 However, the
unopposed vagal activity that occurs with sympathetic block might be another cause of
intraoperative nausea and vomiting during spinal anesthesia.6
Both scopolamine and atropine are tertiary amines, which cross the blood-brain barrier with
central side effects, such as confusion, sedation, or paradoxical excitation. However,
Hyoscine butyl bromide (HBB) has a quaternary ammonium structure that does not cross through
the blood-brain barrier and also with lower placental transfer than atropine, making it more
suitable for use in pregnancy 7, 8.
Hyoscine Butyl-bromide, also known as scopolamine butyl-bromide and sold under the brand name
Buscopan.9 Despite being a quaternary ammonium compound, HBB is still capable of targeting
the chemoreceptor trigger zone due to the lack of a well-developed blood-brain-barrier in the
medulla oblongata, which potentiates the antiemetic effects that it produces through local
action on the smooth muscle of the gastrointestinal tract.10
So, the aim of the current study is to examine the effect of prophylactic use of HBB and
Ondansetron to decrease the incidence of intraoperative bradycardia and thus intraoperative
nausea and vomiting in parturients undergoing CD under spinal anaesthesia.