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Effect of intraoperative warmed, humidified carbon dioxide insufflation in open laparotomy colorectal surgery patients undergoing Cytoreductive surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS HIPEC): a randomized controlled trial (Second WHCO2 trial)

Effect of intraoperative warmed, humidified carbon dioxide insufflation in open laparotomy colorectal surgery on 5-year survival rates of patients undergoing Cytoreductive surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS HIPEC): a randomized controlled trial (Second WHCO2 trial)

Status
Recruiting
Phases
Unknown
Study type
Interventional
Source
ANZCTR
Registry ID
ACTRN12623000950662
Acronym
WHCO2
Enrollment
20
Registered
2023-09-04
Start date
2023-11-09
Completion date
2026-12-31
Last updated
2026-01-27

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

This study aims to determine whether the use of warmed, humidified CO2 to protect the internal membranes within the lower abdomen in patients with peritoneal metastases from colorectal cancer, who are undergoing surgery and internally delivered focussed chemotherapy can reduce the recurrence of abdominal metastases and impact 5 year survival rates. Who is it for? You may be eligible for this study if you are an adult aged between 18 and 70 years of age, you have been diagnosed with colorectal cancer that has spread (metastastised) to other areas within your abdomen and you are eligible to undergo a combined surgical removal and internally delivered chemotherapy procedure called cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. Study details Participants who choose to enrol in this study will be randomly assigned by chance (similar to flipping a coin) to one of two treatment groups. Both groups will undergo the surgical procedure and internally delivered chemotherapy, but one group will also have warmed humidified CO2 gas applied to their internal membranes during the surgery. It is not anticipated that use of the CO2 will extend the duration of the surgery. Participants in both groups will also have tissue samples taken during the surgery for further analysis and will be asked to consent to their health information being accessed by the study team for up to 5 years after the surgery. Participants in both groups will also be asked to attend regular colonoscopies, CT scans and blood tests at regular intervals after the surgery, as per standard care for patients with this type of cancer. It is hoped this research will determine whether use of warmed humidified CO2 during cancer removal surgery has an impact on the future spread of cancer within the abdomen and whether this technique has any impact on 5 year survival rates for patients with metastatic colorectal cancer.

Interventions

Patients in the intervention group will receive warmed (37°C), humidified (98% RH) carbon dioxide. The delivered gas will be defined by the United States Pharmacopeia and National Formulary, which requires impurity of less than 200 parts per million, including water vapour. The gas diffuser will be positioned inside the open abdominal wound cavity (in the epigastric region) at a depth of approximately 4cm from the skin as soon as the abdominal wall retraction has been done. The insufflation of w

Patients in the intervention group will receive warmed (37°C), humidified (98% RH) carbon dioxide. The delivered gas will be defined by the United States Pharmacopeia and National Formulary, which requires impurity of less than 200 parts per million, including water vapour. The gas diffuser will be positioned inside the open abdominal wound cavity (in the epigastric region) at a depth of approximately 4cm from the skin as soon as the abdominal wall retraction has been done. The insufflation of warm humidified CO2 will then start and continue until the abdominal wall retractors are removed and closure of the abdominal wall is commenced (approx. a few hours). The intervention will be delivered by the anaesthesiologist and operation reports will be monitored to ensure consistency in administration of intervention. This medical grade CO2 will be warmed to 37°C and humidified to 98% RH using a humidification system. The HUMIGARD system kits are individually packaged in a sterile manner.

Sponsors

Sydney Local Health District
Lead SponsorGovernment body

Study design

Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
All
Age
18 Years to 70 Years
Healthy volunteers
No

Inclusion criteria

Colorectal adenocarcinoma peritoneal metastases confirmed on biopsy at time of diagnostic laparoscopy, Peritoneal cancer index score (diagnostic laparoscopic) <15, Intention to achieve Completeness of cytoreduction score (CCR) of 0. Willingness to provide informed consent and willingness to participate and comply with the study requirements.

Exclusion criteria

Extraperitoneal metastasis (current), Liver metastases, Non-colorectal adenocarcinoma, Inability to achieve CCR0, Inoperable peritoneal carcinomatosis , PCI on diagnostic laparoscopy of more than 15, During laparotomy for CRS/HIPEC, two surgeons agree and decide tumour spread is so advanced that proceeding with operation is futile or too dangerous (however will be analysed as intention to treat), ECOG score >2, Charlson Comorbidity index more than 8, PCI (diagnostic laparoscopic)>16

Outcome results

None listed

Source: ANZCTR · Data processed: Feb 4, 2026