Clinical trial NCT01723280: Supplemental Oxygen - Effect on Occurrence of Subsequent Cancer After Abdominal Surgery (Follow-up of the PROXI Trial)
Official title: Perioperative Inspiratory Oxygen Fraction - Effect on Occurrence of Subsequent Cancer After Abdominal Surgery (Follow-up of the PROXI Trial)
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Laparotomy
Lead sponsor: Rigshospitalet, Denmark
Sponsor class: OTHER
First posted: 2012-11-07
Enrollment: 1386
Sex: ALL
Minimum age (years): 18
Maximum age (years): 100
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_CONTROL
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Participants in the PROXI trial

Brief summary: Aim: to investigate the effect of a high inspiratory oxygen fraction (FiO2) given during and after laparotomy procedures on occurrence of a subsequent, new or recurrent, cancer diagnosis at a long-term follow-up.

Background: A high inspiratory oxygen fraction (FiO2 = 0.80) has been linked to prevention of surgical site infection, but the Danish randomized clinical multicenter trial, the PROXI trial, found no difference in frequency of surgical site infection. In fact, long-term mortality was significantly increased with a hazards ratio of 1.30 in patients receiving 80% oxygen, and this appeared to be statistically significant in patients undergoing cancer surgery, but not in non-cancer patients.

At this point, no convincing mechanism explains the observed increased mortality after hyperoxia, as the long-term pathophysiological effects of oxygen are not fully understood.

Primary hypothesis of this follow-up study of the PROXI trial: Use of 80% oxygen increase the frequency of patients with a subsequent, new or recurrent, cancer.


Eligibility criteria: Inclusion Criteria:

* Age 18 years or older.
* Laparotomy, acute or elective. In case of gynaecological surgery only if malignancy is suspected (defined as risk of ovarian malignancy index \>200 or a specimen with atypical or neoplastic cells).

Exclusion Criteria:

* Other surgery within 30 days (except surgery in local anaesthesia).
* Chemotherapy within 3 months.
* Inability to give informed consent.
* Inability to keep oxygen saturation above 90% without supplemental oxygen (measured preoperatively by pulse oximetry).

Primary outcomes:
measure: Frequency of patients with the composite outcome measure of either a subsequent, new or recurrent, cancer registration or a new histological specimen showing any neoplasm
timeFrame: 36-60 months after randomization
Secondary outcomes:
measure: Frequency of patients with subsequent, new or recurrent, cancer registration at the Danish Cancer Registry
timeFrame: 15-39 months after randomization
measure: Frequency of patients with new histological specimen in the Danish Patobank showing any neoplasm
timeFrame: 36-60 months after randomization
measure: Frequency of patients with new histological specimen in the Danish Patobank showing neoplasm of a histological type not previously diagnosed
timeFrame: 36-60 months after randomization
measure: Frequency of patients with cancer as diagnosis code at a readmission
timeFrame: 36-60 months after randomization
measure: Frequency of patients with cancer as primary diagnosis code at a readmission
timeFrame: 36-60 months after randomization
measure: Duration of cancer-free survival, as assessed by Kaplan-Meier statistics
timeFrame: 36-60 months after randomization
Other outcomes:
measure: Type of new cancer registration
timeFrame: 15-39 months after randomization
measure: Histological type of new cancer specimen
timeFrame: 36-60 months after randomization
measure: Cause of death
timeFrame: 15-39 months after randomization
Locations:
city: Copenhagen
country: Denmark
facility: Dept. of Anesthesia, HOC, Copenhagen University Hospital, Rigshospitalet
Study officials:
affiliation: Rigshospitalet, Denmark
name: Christian S Meyhoff, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Meyhoff CS, Wetterslev J, Jorgensen LN, Henneberg SW, Simonsen I, Pulawska T, Walker LR, Skovgaard N, Helto K, Gocht-Jensen P, Carlsson PS, Rask H, Karim S, Carlsen CG, Jensen FS, Rasmussen LS; PROXI Trial Group. Perioperative oxygen fraction - effect on surgical site infection and pulmonary complications after abdominal surgery: a randomized clinical trial. Rationale and design of the PROXI-Trial. Trials. 2008 Oct 22;9:58. doi: 10.1186/1745-6215-9-58.
citation: Meyhoff CS, Wetterslev J, Jorgensen LN, Henneberg SW, Hogdall C, Lundvall L, Svendsen PE, Mollerup H, Lunn TH, Simonsen I, Martinsen KR, Pulawska T, Bundgaard L, Bugge L, Hansen EG, Riber C, Gocht-Jensen P, Walker LR, Bendtsen A, Johansson G, Skovgaard N, Helto K, Poukinski A, Korshin A, Walli A, Bulut M, Carlsson PS, Rodt SA, Lundbech LB, Rask H, Buch N, Perdawid SK, Reza J, Jensen KV, Carlsen CG, Jensen FS, Rasmussen LS; PROXI Trial Group. Effect of high perioperative oxygen fraction on surgical site infection and pulmonary complications after abdominal surgery: the PROXI randomized clinical trial. JAMA. 2009 Oct 14;302(14):1543-50. doi: 10.1001/jama.2009.1452.
citation: Meyhoff CS, Jorgensen LN, Wetterslev J, Siersma VD, Rasmussen LS; PROXI Trial Group. Risk of new or recurrent cancer after a high perioperative inspiratory oxygen fraction during abdominal surgery. Br J Anaesth. 2014 Jul;113 Suppl 1:i74-i81. doi: 10.1093/bja/aeu110. Epub 2014 May 23.