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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
A trial to assess which method of delivering local anaesthetic in to the abdominal wall provides the best pain relief after major gynaecological cancer surgery.
Scientific title
A double blinded randomised controlled trial assessing and comparing the total average 24 to 48 hour post surgical morphine usage and analgesic quality of 3 types of abdominal wall block catheters (transversus abdominis plane versus rectus sheath plane versus subcutaneous plane) in participants receiving midline laparotomy for gynaecological oncology surgery.
Secondary ID [1] 281186 0
Universal Trial Number (UTN)
Trial acronym
CAAB trial (Continuous Anterior Abdominal Wall Block)
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Postoperative pain 287362 0
Gynaecological cancer 287381 0
Condition category
Condition code
Anaesthesiology 287692 287692 0 0
Cancer 287713 287713 0 0
Ovarian and primary peritoneal
Cancer 287714 287714 0 0
Womb (Uterine or endometrial cancer)

Study type
Description of intervention(s) / exposure
Participants are randomised to receive either a catheter inserted in to transversus abdominis plane, rectus sheath plane or subcutaneous plane. All procedures will be performed at the end of the operation whilst under general anaesthesia by one of the investigators. During surgery participants will receive prophylactic antiemetics (Metoclopramide 20mg and Tropisetron 2mg intravenously) and a single dose of Parecoxib 40mg intravenously (unless contraindicated). All groups for a duration og 48 hours post surgery will receive 18ml boluses of 0.5% ropivacaine every 4 hours via a Y catheter (9 mls each side) at a total of 540 mg/day . The participants will be studied for 48 hours and the catheter will remain in situ for this time. The catheters will be removed on the third post operative day (48-72 hours post surgery). In addition for the first 48 hours post surgery patients will receive pain relief in the form of a morphine PCA and regular paracetamol. Intravenous antiemetics will be administered as required.
Intervention code [1] 285646 0
Treatment: Other
Intervention code [2] 285668 0
Treatment: Devices
Comparator / control treatment
The morphine consumption will be compared in the three catheter groups. It is hypothesised that the subcutaneous catheter group will provide the least effective analgesia and thus is our control group
Control group

Primary outcome [1] 287941 0
To compare the total average 24 to 48 hour post surgical morphine usage between the three groups (transverse abdominis plane (TAP) catheter group, posterior rectus sheath (PRS) catheter group and subcutaneous catheter group).
Timepoint [1] 287941 0
measured at 24 and 48 hours post surgery
Secondary outcome [1] 299085 0
VAS pain scores at rest and movement
Timepoint [1] 299085 0
24 and 48 hours post surgery
Secondary outcome [2] 299086 0
Peak flow measurements (hand held peak flow meter, best of three)
Timepoint [2] 299086 0
24 and 48 hours
Secondary outcome [3] 299087 0
Nausea and vomiting scores (VAS - 0-10cm line)
Timepoint [3] 299087 0
24 and 48 hours
Secondary outcome [4] 299088 0
average sedation scores (0-3 nurse assessed)
Timepoint [4] 299088 0
0-24 and 24-48 hours post surgery
Secondary outcome [5] 299089 0
Patient satisfaction scores : 3 question VAS scale (How would you rate your satisfaction with the pain relief? If you needed another operation will you request the same analgesia again? Would you recommend this type of analgesia to a friend?)
Timepoint [5] 299089 0
at 24 and 48 hours

Key inclusion criteria
Women who are undergoing a laparotomy for gynaecological oncology procedures with an expected midline incision.
Minimum age
18 Years
Maximum age
No limit
Can healthy volunteers participate?
Key exclusion criteria
Conditions associated with opioid tolerance: regular opioid analgesia use in the last three months, previous IVDU
Abdominal wall block technically difficult to perform: eg obesity (BMI > 35)
Contraindication to abdominal wall block: local sepsis, local anaesthetic allergy, abnormal anatomy (for example nephrectomy scars)
Preference for other technique for postoperative analgesia, such as epidural infusion.
Presence of stoma
Age less than 18.
Inadequate capacity to consent

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Recruitment and consent
All patients of the Mater Adult Public Hospital undergoing midline laparotomy for gynaecological oncology procedures will be eligible.
Patients will be given an information sheet when booked for surgery by the gynaecological oncologist. They will have the opportunity to discuss the trial with an anaesthetist at an anaesthetic assessment clinic and written consent will be obtained if possible.
Patients will then be approached on the day of surgery in the admissions area (or their room) by the investigator. They will be reassessed for the inclusion and exclusion criteria and, once consent has been obtained, the baseline data will be collected.
If suitable for the study, information about the study will be reiterated: study purpose; design; benefits; and risks. Informed consent will be obtained if not yet done so.
Study participants will verify that they have read and understood the information sheet and verify that they have had any questions about the study answered and then read and sign the consent form
Once consent is obtained, the treating anaesthetist will be notified of the patient's enrolment. If the treating anaesthetist is an investigator, another investigator will seek consent from the patient.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer random allocation software will be used to generate a simple random sequence table prior to the start of the trial using three groups and a sample size of 90.
The randomisations will be concealed in 90 sealed envelopes labelled participant 1 to 90.
After obtaining written consent and commencement of anaesthesia (immediately after a midline incision has been performed), an envelope will be opened revealing the participant’s allocated group (A,B or C : A=Subcutaneous infusion catheter, B=TAP infusion catheter or C=Posterior rectus sheath catheter).
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Participants are randomised to receive one of 3 interventions (transversus abdominis/rectus sheath/subutaneous catheters) after their abdominal surgery. After 90 participants have completed the trial each group will be statistically analysed and compared.
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 285961 0
Name [1] 285961 0
Mater Anaesthetic research fund
Address [1] 285961 0
Mater Health Services
Raymond Terrace
South Brisbane
QLD 4101
Country [1] 285961 0
Primary sponsor type
Mater Health Services
Mater Health Services
Raymond Terrace
South Brisbane
QLD 4101
Secondary sponsor category [1] 284785 0
Name [1] 284785 0
Address [1] 284785 0
Country [1] 284785 0

Ethics approval
Ethics application status
Ethics committee name [1] 287995 0
Mater Health Services Human Research Ethics Committee
Ethics committee address [1] 287995 0
Mater Human Research Ethics Office
Mater Medical Research Institute
Room 56
Level 3
Quarters Building
Annerley Road
Qld 4102
Ethics committee country [1] 287995 0
Date submitted for ethics approval [1] 287995 0
Approval date [1] 287995 0
Ethics approval number [1] 287995 0
Ref No. 1912AM

Brief summary
This study will investigate the quality of post surgical pain relief in patients who have undergone major gynaecological cancer surgery. Who is it for? You may be eligible to join this study if you are a woman aged 18 years or above, who is undergoing a laparotomy for gynaecological cancer procedures. Trial details Participants in this trial will be randomly (by chance) allocated to have their catheter inserted into one of three positions on the abdomen (i.e. abdominis plane, rectus sheath plane, or subcutaneous plane) at the end of their surgery whilst under general anaesthesia. The catheter is used to deliver pain-reducing medication and will remain in place for 48-72 hours post surgery. The total morphine consumption, pain, nausea and patient satisfaction will be compared amongst the three groups at 24 and 48 hours post surgery. It is hoped that the study will show that the patients who receive the rectus sheath block and transversus abdominis block will have more effective pain relief and require less morphine compared with the subcutaneous catheter group. Less morphine should reduce side effects and improve patient satisfaction.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 34683 0
Address 34683 0
Country 34683 0
Phone 34683 0
Fax 34683 0
Email 34683 0
Contact person for public queries
Name 17930 0
Phillip Cowlishaw
Address 17930 0
Mater Health Services
Raymond Terrace
South Brisbane
QLD 4101
Country 17930 0
Phone 17930 0
+61 7 31638646
Fax 17930 0
Email 17930 0
Contact person for scientific queries
Name 8858 0
Phillip Cowlishaw
Address 8858 0
Mater Health Services
Raymond Terrace
South Brisbane
QLD 4101
Country 8858 0
Phone 8858 0
+61 7 31638646
Fax 8858 0
Email 8858 0

No information has been provided regarding IPD availability
Summary results
No Results