Prevention of nausea and vomiting comparing ondansetron and dexamethasone versus placebo in cesarean section under regional anesthesia

ISRCTN ISRCTN57227250
DOI https://doi.org/10.1186/ISRCTN57227250
Secondary identifying numbers .
Submission date
07/07/2016
Registration date
17/07/2016
Last edited
09/08/2019
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Signs and Symptoms
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English summary of protocol

Background and study aims
A caesarean is an operation used to deliver a baby, which can be planned or used as an emergency procedure, when a natural birth is not an option. It involves making a cut in the mother’s tummy (abdomen) wall and the womb, through which the baby is taken through. A caesarean can be a planned (elective) procedure, if the need for it becomes apparent during pregnancy or if the mother asks for it. The procedure is usually performed when the woman is awake under regional anaesthtic (numbing of the lower half of the body). This often involves an injection of an anaesthetic (numbing agent) and pain killer (such as morphine) mixture into the spine in the lower back. The use of intrathecal (injection into the spine) morphine is an effective method for pain relief in postoperative cesarean section, but has undesirable side effects such as nausea, vomiting and itching. The aim of this study is to test two drugs to find out if they can reduce nausea, vomiting and itching after receiving intrathecal morphine: dexamethasone (which prevents inflammation (swelling)) and ondansetron (which blocks the chemicals in the body which can trigger nausea and vomiting).

Who can participate?
Pregnant women aged between 18 and 40 who are scheduled for an elective caesarean section with spinal pain relief.

What does the study involve?
Participants are randomly allocated to one of three groups, who each receive a different treatment through a drip when they have their pain killer injection into the spine before surgery. Those in the first group receive 4mg of ondansetron in 5ml normal saline (salt water). Those in the second group receive 4mg of dexamethasone in 5ml normal saline. Those in the third group receive 5ml normal saline only with no drugs added. During surgery and then two, six and 24 hours afterwards, participants in all groups are asked to rate their nausea and any vomiting is recorded. The risk of nausea and vomiting is then calculated for each group. Participants are also asked whether their skin feels itchy so that the risk of itchy skin can be calculated.

What are the possible benefits and risks of participating?
Participants benefit from having more intensive monitoring and timely management of vomiting or nausea after their surgery. There are no notable risks involved with participating in this study.

Where is the study run from?
Clinica materno infantil San Luis (Columbia)

When is the study starting and how long is it expected to run for?
February 2014 to September 2016

Who is funding the study?
Industrial University of Santander (Columbia)

Who is the main contact?
Dr Rodolfo Parra Güiza

Contact information

Dr Rodolfo Parra Güiza
Public

Hospital universitario de Santander
Departamento de Cirugía
Piso 9
Oficina 901
Cra. 30 #34-54
Bucaramanga.
680002
Colombia

Study information

Study designSingle-centre randomized placebo-controlled triple-blind trial
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Hospital
Study typeTreatment
Participant information sheet No participant information sheet available
Scientific titleProphylaxis of postoperative nausea and vomiting in cesarean section under spinal anesthesia with intrathecal morphine: controlled clinical trial comparing ondansetron vs placebo vs dexamethasone
Study objectivesDexamethasone and Ondansetron are better than placebo for the prevention of nausea and vomiting in patients undergoing cesarean section under regional anesthesia and intrathecal morphine.
Ethics approval(s)Institutional review board of the Clínica materno infantil San Luis (Colombia), 18/01/2014
Health condition(s) or problem(s) studied1. Postoperative nausea and vomiting
2. Pruritus
Intervention300 patients are randomized to one of three groups in a 1:1:1 ratio.

Ondansetron group: Participant receive 4 mg of ondansetron in 5 mL normal saline
Dexamethasone group: Participant receive 4 mg of dexamethasone in 5 mL normal saline
Placebo group: Participant receive 5 mL normal saline

In all groups, study drugs are administered at the time of lumbar puncture for the administration of the anesthetic-analgesic mixture (9 mg of bupivacaine + 25 micrograms fentanyl 100 micrograms of morphine) by the anesthesiologist responsible for the case.

Patients are evaluated intraoperatively, and then 2, 6 and 24 hours after intrathecal morphine. They are questioned about nausea and vomiting, need for rescue antiemetics, itching and pain using a numeric scale to indicate the severity of these symptoms (nausea, itching and pain). If patients have vomiting or severe nausea (numerical rating scale >7) postoperatively, they receive 4 mg of dexamethasone and 4 mg of ondansetron as antiemetic rescue therapy.
Intervention typeDrug
Pharmaceutical study type(s)
PhasePhase IV
Drug / device / biological / vaccine name(s)Ondansetron, Dexamethasone, Normal saline
Primary outcome measure1. Incidence of nausea and vomiting is measured using a numerical rating scale (NRS) at 2, 6 and 24 hours after intrathecal morphine
2. Relative risk of nausea and vomiting by dividing the percentage cases of nausea and vomiting in the control group by the percentage cases in each of the intervention groups
3. Number needed to treat for nausea and vomiting is measured by the inverse of the Absolute Risk reduction (ARR) (% of cases of nausea on placebo group - % of cases of nausea on ondansetron or dexamethasone group) intraoperatively, at 2, 6 and 24 hours after intrathecal morphine
Secondary outcome measures1. Incidence of pruritus is measured using a numerical rating scale (NRS) intraoperatively, at 2, 6 and 24 hours after intrathecal morphine
2. Relative risk of pruritus by dividing the percentage cases of pruritus in the control group by the percentage cases in each of the intervention groups
Overall study start date22/02/2014
Completion date01/09/2016

Eligibility

Participant type(s)Patient
Age groupAdult
Lower age limit18 Years
SexFemale
Target number of participants300
Total final enrolment300
Key inclusion criteria1. Pregnant patients scheduled for elective caesarean
2. Age between 18 - 40 years old
3. Spinal (Subarachnoid) anesthesia with intrathecal morphine
4. ASA Physical status 1-2
Key exclusion criteria1. Preeclampsia
2. Eclampsia
3. Kidney and/or liver failure
4. Known allergy to ondansetron or dexamethasone
5. Heart disease
6. Vertigo
7. Hyperemesis gravidarum
8. Nausea and vomiting or itching
9. Previous cesarean section
10. 5 HT3 antagonists or corticoids allergy
11. Gestational diabetes
12. Immunosuppression
13. Congenital long QT syndrome
14. Neurological or psychiatric illness that would prevent obtaining consent for the study Emergency Caesarean
.
Date of first enrolment17/09/2015
Date of final enrolment11/12/2015

Locations

Countries of recruitment

  • Colombia

Study participating centre

Clinica materno infantil San Luis
Cra. 26 #48-56
Bucaramanga
680003
Colombia

Sponsor information

Industrial University of Santander (Universidad Industrial de Santander)
Hospital/treatment centre

Cra. 30 #34-54
Bucaramanga
680002
Colombia

ROR logo "ROR" https://ror.org/00xc1d948

Funders

Funder type

University/education

Industrial University of Santander (Universidad Industrial de Santander)

No information available

Results and Publications

Intention to publish date01/09/2017
Individual participant data (IPD) Intention to shareYes
IPD sharing plan summaryAvailable on request
Publication and dissemination planPlanned publication in a high-impact peer reviewed journal.
IPD sharing plan

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Results article results [in Spanish] 30/04/2018 09/08/2019 Yes No

Editorial Notes

09/08/2019: The following changes have been made:
1. Publication reference added.
2. The final enrolment number has been added from the reference.