None listed
Conditions
Brief summary
The World Health Organisation (WHO) and Centre for Disease Control (CDC) guidelines recommend liberal provision of oxygen intraoperatively and in the early post-operative period to reduce the risk of post-operative infection. However, evidence from related specialties indicates that overall, liberal oxygen therapy may be increase mortality and non-infection-related complications compared with restricted oxygen therapy raising the possibility that any decreased infection risk might come at the cost of an increased risk of other complications. For adults having major surgery, it is biologically plausible that more restricted use of oxygen therapy than occurs in standard practice might improve patient outcomes; however, it is also biologically plausible that more liberal oxygen therapy might improve patient outcomes compared with standard care. Overall, the optimal approach to oxygen therapy in the setting of major surgery is uncertain. HOT-ROX will be the first trial evaluating restricted oxygen therapy vs. standard care and liberal oxygen therapy vs. standard care in patients having major surgery that is powered to assess the effect of these treatments on days alive and at home at 30 days (DAAH30). DAAH30 is strongly associated with the occurrence of postoperative complications and encapsulates the patient-important effects of such complications because it effectively combines hospital length of stay, readmission episodes, discharge destination and early post-operative mortality into a single outcome measure. The first interim analysis is planned after recruitment of 210 participants and in addition to predefined early stopping criteria will assess the listed feasibility outcomes.
Interventions
Following randomisation, participants will be allocated to restricted oxygen therapy (intervention 1), liberal oxygen therapy (intervention 2) or standard care oxygen therapy (control). In all three arms, the allocated oxygen therapy will be started after induction of anaesthesia, confirmation of artificial airway placement, and patient positioning are completed. The duration of the study will be until discharge from PACU or ICU, or 6 hours after transfer out of operating theatre, whichever occu
Following randomisation, participants will be allocated to restricted oxygen therapy (intervention 1), liberal oxygen therapy (intervention 2) or standard care oxygen therapy (control). In all three arms, the allocated oxygen therapy will be started after induction of anaesthesia, confirmation of artificial airway placement, and patient positioning are completed. The duration of the study will be until discharge from PACU or ICU, or 6 hours after transfer out of operating theatre, whichever occurs sooner. In the restricted arm, the overarching aim is to avoid giving a greater FiO2 than is necessary to achieve an SpO2 greater than or equal to 93%. Intra-operatively, anaesthetists will use the lowest FiO2 that they consider safe to achieve the target SpO2, by titrating the inspired oxygen concentration delivered via the anaesthesia machine ventilator. Although anaesthetic machines are capable of delivering FiO2<0.21, use of such hypoxic gas mixtures will be prohibited. Following surgery, in the PACU or ICU, the FiO2 will be reduced as rapidly as possible while continuing to aim for an SpO2 of greater than or equal to 93% and supplemental oxygen will be ceased when possible. In the liberal arm, the overarching aim will be to administer oxygen liberally in accordance with the current WHO recommendations on intraoperative and postoperative measures for surgical site infection prevention. Once the study intervention period starts, an FiO2 of =0.8 will be administered. Following surgery, this regimen will continue until extubation after which time oxygen will be administered at 15L/min via a non-rebreather mask. If a patient receives non-invasive ventilation or high flow oxygen therapy, an FiO2 of =0.8 will be used.
Sponsors
Medical Research Institute of New Zealand
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 No maximum
Healthy volunteers
No
Inclusion criteria
• Patients undergoing non-cardiac surgery under general anaesthesia with an expected duration of at least 2 hours and anticipated in-hospital stay of at least 1 post-operative night • American Society of Anaesthesiologists Physical Status Classification (ASA) 3 or 4
Exclusion criteria
• Current pregnancy • The treating clinicians consider that there is a specific indication for either liberal or restricted oxygen therapy in the perioperative period • Previously enrolled in the HOT-ROX study
Outcome results
None listed