Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12615001231538
Ethics application status
Approved
Date submitted
30/06/2015
Date registered
10/11/2015
Date last updated
10/11/2015
Type of registration
Prospectively registered

Titles & IDs
Public title
Is Intraoperative tissue oxygenation increased with humidified carbon dioxide (CO2)
Scientific title
Effect of warm humidified carbon dioxide on tissue oxygenation in open abdominal surgery - a pilot study.
Secondary ID [1] 287089 0
Abdominal surgery
Secondary ID [2] 287679 0
nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Tissue oxygenation 295491 0
abdominal surgery 295601 0
Condition category
Condition code
Surgery 295744 295744 0 0
Surgical techniques
Oral and Gastrointestinal 295878 295878 0 0
Other diseases of the mouth, teeth, oesophagus, digestive system including liver and colon

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The purpose of the research is to investigate whether insufflation of warm, humidified carbon dioxide into the open abdominal cavity during open abdominal surgery can increase sub-peritoneal tissue oxygen partial pressure. The amount of oxygen is an important indicator of tissues’ ability to resist infection and possibly post-operative adhesions.

The CO2 insufflation gas will be warmed to approximately 37 degrees C, humidified to > 90 % relative humidity and delivered to the surgical field using a humidifier and heated tube (Surgical Humidification System, Fisher & Paykel Healthcare, Auckland, New Zealand) The gas will pass through a diffuser (VitaDiffuser, Cardia Innovation AB, Stockholm, Sweden) placed at the edge of the surgical wound, approximately 2 cm within the peritoneal cavity. The gas flow rate will be 10 L/min, as this has been shown to be the flow rate necessary to main a CO2 surgical microclimate despite the use of suction and movement of hands and instruments within the surgical cavity

Following stabilisation of the oxygen partial pressure probe (30 minutes as per manufacturers instruction), the subject will be randomized to recieve either heated humidifed gas on or gas off (standard care) for 30 minute intervals, at the end of the 30 minute interval the alternative treatment will be applied and so on and so forth until the end of the procedure. . If the surgery is completed before the end of a 30 minute interval, data recorded during that interval will be excluded from the analysis. During the trial all surgeries and the placements of the device and probe will be performed by surgeon Ai Ling Tan.
Intervention code [1] 292231 0
Treatment: Other
Intervention code [2] 292331 0
Treatment: Devices
Comparator / control treatment
Pilot trial:

Standard care - no gas is applied to the abdominal cavity for 30minute periods.

.
Control group
Active

Outcomes
Primary outcome [1] 295464 0
Composite outcome of PtO2 and temperature. PtO2 and tissue temperature measurements will be averaged over the last minute for each treatment condition. Each treatment will be paired with the alternate treatment (the first treatment with the second, third with the fourth etc.) to give a change in PtO2 and tissue temperature for each cross-over trial.
Infrared and Digital thermometer will be used to asses each of PtO2 and temperature.
Timepoint [1] 295464 0
the subject will be randomized to recieve either heated humidifed gas on or gas off (standard care) for 30 minute intervals, at the end of the 30 minute interval the alternative treatment will be applied and so on and so forth until the end of the procedure. . If the surgery is completed before the end of a 30 minute interval, data recorded during that interval will be excluded from the analysis. During the trial all surgerieys and the placements of the device and probe will be performed by gynaeoncology surgeon Ai Ling Tan .Prathima Chowdary will be present during the procedures and will document the readings from the oxygen probe and case report form details. PtO2 and temperature are assessed over the last minute of each intervention and control period.
Primary outcome [2] 296486 0
tissue oxygenation PTO2 measured with a probe.
Timepoint [2] 296486 0
30 mins.
Secondary outcome [1] 318589 0
Tissue temperature with a digital thermometer
Timepoint [1] 318589 0
30mins

Eligibility
Key inclusion criteria
Scheduled to undergo an elective open abdominal surgical procedure with an intra-abdominal component. For gynaecological surgeries, surgery is expected to last >1 hour. Standard midline wound incision which is atl east 2cm deep so that the wounds are standardised. No additional incisions required for the trial.
18 years old
Maximum eligible age of 80years.
BMI <35
Minimum age
18 Years
Maximum age
80 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Inability to give informed consent
Already participated in this trial
Pregnant
Received radiotherapy to the incision site in the last 4 weeks
Has an infection at the time of surgery at the site of incision
After opening of the abdominal wall, surgeon determines that an appropriate intra-abdominal site for insertion of the oxygen probe does not exist. A likely cause may be diffuse peritoneal adhesions.
A medical condition that affects haemoglobin saturation or will have a direct impact on perfusion, including severe lung disease.
1 hour time criterion only apply to gynaecological surgeries The trial will be taking place in the gynaeoncology department.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Potential participants will be identified by their consulting surgeon following the decision that a patient will undergo elective open abdominal surgery and that the project is suitable for the potential participant.
Participants will be invited to join the trial by their surgeon prior to their planned procedure, with enough notice to ensure that they have time to take away the participant information sheet and trial consent form and consider their participation decision. The information sheet and consent forms will be read to the potential participant either by one of their surgeons or by Prathima Chowdary and they will have the opportunity to ask any questions they may have. Potential participants will also be given a copy of the trial consent form they will need to sign if they agree to participate. (Note that trial consent is separate from consent for the planned surgical procedure.)
If they chose to participate, they will be asked contact Prathima Chowdary by phone or by returning the consent form in the supplied pre-addressed envelope.
On the consent form participants will be asked to indicate if they would like to be contacted to receive a summary of the overall study results following the completion of the project. If the participant indicates that they would like to be contacted with the results, they will be asked to fill in a separate contact form with their name and address so that a summary of the overall study results can be posted to them. This form will be kept separately and will not be stapled to the participant consent form.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomisation will occur after consent is obtained and after the patient’s eligibility is confirmed based on the inclusion and exclusion criteria. Randomization will be conducted using random numbers obtained by a computer-based random number generator. Concealment will be achieved by the use of opaque envelopes opened at surgery by a third party.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Blinding will not be conducted during this trial. It is not possible to blind the surgeon(s) to the group allocation as the warm humidified insufflation gas can be felt by the surgeon’s hands in the surgical fieldAs each subject will receive each intervention during a single surgical procedure and no post-operative data will be collected, blinding of the subject or post-operative staff is not necessary.
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
PtO2 and tissue temperature measurements will be averaged over the last minute for each treatment condition. Each treatment will be paired with the alternate treatment (the first treatment with the second, third with the fourth etc.) to give a change in PtO2 and tissue temperature for each cross-over trial. The Shapiro-Wilk test will be used to check the normality of the data set for each experiment. When the assumption of normality was satisfied, a paired Student’s t-test will be conducted to test whether the mean change between paired treatment conditions differed from zero. When the assumption of normality was not satisfied, a Hodges-Lehman median difference and Wilcoxon Signed Rank test will be used. A P-value <0.05 will be considered statistically significant for all tests.
Sample SizeBased on the average increase shown in pilot animal work to achieve a increase in oxygenation of 25 mmHg which is deemed clinically significant a sample size of at least nine with two interventions in each sample will give a power of greater than 99% at significance level of 0.001.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
30/11/2015
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
10
Accrual to date
Final
Recruitment outside Australia
Country [1] 7013 0
New Zealand
State/province [1] 7013 0
Auckland

Funding & Sponsors
Funding source category [1] 291577 0
Hospital
Name [1] 291577 0
North Shore Hospital
Country [1] 291577 0
New Zealand
Primary sponsor type
Government body
Name
Auckland District Health Board
Address
Private Bag 93503 Takapuna North Shore 0740
Fellow Obstetrics and Gynaecology Gynaecology
Waitemata District Health Board
Country
New Zealand
Secondary sponsor category [1] 290250 0
None
Name [1] 290250 0
None
Address [1] 290250 0
None
Country [1] 290250 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 293113 0
Northern B Health and Disability Ethics Committees (HDECs).
Ethics committee address [1] 293113 0
Ethics committee country [1] 293113 0
New Zealand
Date submitted for ethics approval [1] 293113 0
06/07/2015
Approval date [1] 293113 0
13/10/2015
Ethics approval number [1] 293113 0

Summary
Brief summary
Hypothesis :
Angiogenesis depends on adequate oxygenation and is enhanced by high PtO2

Aims
Maintanence of adequate tissue perfusion and oxygenation in patients undergoing open abdominal surgery
To quantify the effect on tissue oxygenation, of insufflation of warm-humidified CO2 into the abdominal cavity during open abdominal surgery in humans.
The primary endpoint for this trial is tissue oxygen partial pressure. Secondary endpoints are arterial oxygen partial pressure (PaO2), arterial carbon dioxide partial pressure (PaCO2), arterial haemoglobin oxygen saturation and core body temperature.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 58526 0
Dr Prathima Chowdary
Address 58526 0


Private Bag 93503 Takapuna North Shore 0740
Waitemata District Health Board
North Shore Hospital
Country 58526 0
New Zealand
Phone 58526 0
+64210497440
Fax 58526 0
Email 58526 0
[email protected]
Contact person for public queries
Name 58527 0
Dr Prathima Chowdary
Address 58527 0


Private Bag 93503 Takapuna North Shore 0740
Waitemata District Health Board
North Shore Hospital
Country 58527 0
New Zealand
Phone 58527 0
+64210497440
Fax 58527 0
Email 58527 0
[email protected]
Contact person for scientific queries
Name 58528 0
Dr Prathima Chowdary
Address 58528 0


Private Bag 93503 Takapuna North Shore 0740
Waitemata District Health Board
North Shore Hospital
Country 58528 0
New Zealand
Phone 58528 0
+64210497440
Fax 58528 0
Email 58528 0
[email protected]

No information has been provided regarding IPD availability


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.