Trial record 2 of 3 for:    ENIGMA | nitrous oxide

ENIGMA - Evaluation of Nitrous Oxide In the Gas Mixture for Anaesthesia: a Randomised Controlled Trial

This study has been completed.
Sponsor:
Collaborators:
National Health and Medical Research Council, Australia
Australia: Theapeutic Goods Administration
Information provided by:
Bayside Health
ClinicalTrials.gov Identifier:
NCT00164047
First received: September 13, 2005
Last updated: July 29, 2009
Last verified: July 2009

September 13, 2005
July 29, 2009
April 2003
December 2004   (final data collection date for primary outcome measure)
The primary endpoint is hospital length of stay (LOS), defined from the start of surgery until actual hospital discharge. Patients transferred to another hospital will be tracked until final discharge to home (or other final destination). LOS is likely
Same as current
Complete list of historical versions of study NCT00164047 on ClinicalTrials.gov Archive Site
  • Secondary endpoints will be detected by a research assistant who will be masked to Group identity, using chart review up to 30 days postoperatively; confirmation of each will be sought by an independent member of the Endpoint Committee:
  • Wound infection - if associated with purulent discharge or a positive microbial culture (46)
  • Myocardial infarction - confirmed by ECG and/or troponin or CK-MB enzyme rise
  • Venous thromboembolism - symptomatic DVT or PE, confirmed by venography, duplex ultrasonography, V-Q scan or spiral CT, or autopsy
  • Stroke - a new neurological deficit persisting for 24 hours, confirmed by neurologist assessment and/or CT scan or MRI
  • Awareness - postoperative recollection of intraoperative events
  • Blood transfusion - any red cell transfusion within 30 days of surgery
  • Pneumothorax, atelectasis, or pneumonia - confirmed by chest x-ray; for pneumonia: also 2 or more of temp> 38oC, white cell count >12,000/ml, positive sputum culture
  • Severe vomiting - at least 2 episodes >6 hrs apart, or if requiring >2 doses of antiemetic medication
  • Quality of recovery on the morning after surgery -using the validated QoR Score instrument (14), a 9-item patient-orientated measure of early postoperative health status. This is associated with patient satisfaction.
  • 30-day mortality - for safety analysis only (study not powered for this rare event).
  • Secondary endpoints will be detected by a research assistant who will be masked to Group identity, using chart review up to 30 days postoperatively; confirmation of each will be sought by an independent member of the Endpoint Committee:
  • 1. Wound infection – if associated with purulent discharge or a positive microbial culture (46)
  • 2. Myocardial infarction - confirmed by ECG and/or troponin or CK-MB enzyme rise
  • 3. Venous thromboembolism - symptomatic DVT or PE, confirmed by venography, duplex ultrasonography, V-Q scan or spiral CT, or autopsy
  • 4. Stroke – a new neurological deficit persisting for 24 hours, confirmed by neurologist assessment and/or CT scan or MRI
  • 5. Awareness – postoperative recollection of intraoperative events
  • 6. Blood transfusion – any red cell transfusion within 30 days of surgery
  • 7. Pneumothorax, atelectasis, or pneumonia – confirmed by chest x-ray; for pneumonia: also 2 or more of temp> 38oC, white cell count >12,000/ml, positive sputum culture
  • 8. Severe vomiting – at least 2 episodes >6 hrs apart, or if requiring >2 doses of antiemetic medication
  • 9. Quality of recovery on the morning after surgery –using the validated QoR Score instrument (14), a 9-item patient-orientated measure of early postoperative health status. This is associated with patient satisfaction.
  • 10. 30-day mortality – for safety analysis only (study not powered for this rare event).
Not Provided
Not Provided
 
ENIGMA - Evaluation of Nitrous Oxide In the Gas Mixture for Anaesthesia: a Randomised Controlled Trial
Evaluation of Nitrous Oxide In the Gas Mixture for Anaesthesia: a Randomised Controlled Trial

We aim to investigate the effectiveness and safety of nitrous oxide (N2O) in anaesthesia.

Hypothesis In patients undergoing anaesthesia for major surgery, avoidance of N2O will reduce hospital length of stay when compared with otherwise identically managed surgical patients receiving N2O as a component of their anaesthesia.

There are some compelling reasons to question the routine use of nitrous oxide (N2O), also known as "laughing gas". Despite being the first anaesthetic drug introduced, and still widely used, there is sufficient doubt as to the risk-benefit profile.

There is strong evidence that N2O is a major risk factor for postoperative nausea and vomiting. It is clear that (even) brief exposure to N2O impairs methionine synthetase, an enzyme required for DNA production, red and white blood cell formation. Tissue hypoxia may be more common. These adverse effects are enhanced in "sick" patients (ie. those at highest risk, increased hospital length of stay and healthcare expenditure), and will be more likely in longer surgery. The extent of wound infection and cardiac morbidity associated with N2O is not known.

Large outcome trial data are lacking. When considering its widespread use in about 90% of all surgery around the world, small differences in outcome would have major implications for healthcare delivery. A large randomised controlled trial is necessary to answer this question.

We have recruited 2000 patients from about 25 centres around the world (mostly Australasia), who are undergoing major surgery.

Interventional
Phase 4
Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind
Primary Purpose: Prevention
  • Quality of Recovery From Anaesthesia
  • Effects of Nitrous Oxide Following Anaesthesia
  • Induced Endothelial Dysfunction
Drug: Nitrous Oxide
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Completed
2070
December 2004
December 2004   (final data collection date for primary outcome measure)

Inclusion Criteria:

  1. Males and females, age 18 years and over
  2. Planned general anaesthesia for surgery that includes a skin incision and expected to exceed two hours, and the patient is expected to be in hospital for at least three days

Exclusion Criteria:

  1. Endoscopic or radiological procedures
  2. Cardiac surgery
  3. Marked impairment of gas-exchange (requiring Fi02> 0.3)
  4. Thoracic surgery requiring one-lung ventilation (requiring Fi02> 0.3)
  5. Specific circumstances where N2O is contraindicated (eg. volvulus, pulmonary hypertension, raised intracranial pressure)
  6. Lack of provision of N2O.
Both
18 Years and older
No
Contact information is only displayed when the study is recruiting subjects
Australia
 
NCT00164047
204/02, NHMRC 236956
Not Provided
Not Provided
Bayside Health
  • National Health and Medical Research Council, Australia
  • Australia: Theapeutic Goods Administration
Principal Investigator: Paul S Myles, MB BS MPH MD The Alfred
Bayside Health
July 2009

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP