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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/study/NCT01092923

Registration number

NCT01092923

Ethics application status

Date submitted

10/03/2010

Date registered

25/03/2010

Date last updated

12/10/2012

Titles & IDs

Public title

Physiological Effects of Nitrous Oxide on Anaesthesia

Scientific title

Nitrous Oxide and Inhalational Agent Pharmacokinetics During Anaesthetic Induction and Emergence

Secondary ID [1]

03749

Universal Trial Number (UTN)

Trial acronym

Linked study record

Health condition

Health condition(s) or problem(s) studied:

Anesthesia

Condition category

Condition code

Intervention/exposure

Study type

Interventional

Description of intervention(s) / exposure

Treatment: Drugs - sevoflurane on air/O2
Treatment: Drugs - sevoflurane in N2O/O2

Experimental: Air/Oxygen - Sevoflurane with Air/Oxygen Mix

Experimental: sevoflurane in N2O/O2 -

Treatment: Drugs: sevoflurane on air/O2
sevoflurane on air/O2

Treatment: Drugs: sevoflurane in N2O/O2
sevoflurane in N2O/O2

Intervention code [1]

Treatment: Drugs

Comparator / control treatment

Control group

Outcomes

Primary outcome [1]

Pa t/Pa0 Sevo (Arterial Partial Pressure of Sevoflurane), t=Time(Minutes)

Timepoint [1]

Baseline, 2 minutes, 5 minutes, and 30 minutes after emergence

Primary outcome [2]

PA t/PA0 Sevo (End Tidal Partial Pressure of Sevoflurane), t=Time (Minutes)

Timepoint [2]

Baseline, 2 minutes, and 5 minutes after emergence

Secondary outcome [1]

Time to Eye Opening

Timepoint [1]

20 Minutes

Eligibility

Key inclusion criteria

* Adult patients undergoing elective general or orthopaedic surgery under relaxant general anaesthesia anticipated to take >1 hour

Minimum age

18 Years

Maximum age

No limit

Sex

Both males and females

Can healthy volunteers participate?

Yes

Key exclusion criteria

* Age under 18 years
* Morbid obesity BMI > 35
* Severe or moderately severe lung disease (FEV1 < 1.0L, FEV1/FVC < 50%)
* Past history of severe post-operative nausea and vomiting
* Pregnancy

Study design

Purpose of the study

Treatment

Allocation to intervention

Randomised controlled trial

Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)

Methods used to generate the sequence in which subjects will be randomised (sequence generation)

Masking / blinding

Blinded (masking used)

Who is / are masked / blinded?

The people receiving the treatment/s

Intervention assignment

Parallel

Other design features

Phase

Phase 4

Type of endpoint/s

Statistical methods / analysis

Recruitment

Recruitment status

Completed

Data analysis

Reason for early stopping/withdrawal

Other reasons

Date of first participant enrolment

Anticipated

Actual

1/10/2009

Date of last participant enrolment

Anticipated

Actual

Date of last data collection

Anticipated

Actual

1/10/2010

Sample size

Target

Accrual to date

Final

Recruitment in Australia

Recruitment state(s)

VIC

Recruitment hospital [1]

Austin Health - Melbourne

Recruitment postcode(s) [1]

3084 - Melbourne

Funding & Sponsors

Primary sponsor type

Government body

Name

Austin Health

Address

Country

Ethics approval

Ethics application status

Summary

Brief summary

Nitrous oxide is the oldest anaesthetic agent still in routine use today. Despite huge changes in the pharmacology of volatile anaesthetic agents and intravenous anaesthetics, the unique properties of nitrous oxide have maintained its place in modern practice, where it is used in combination with other, more powerful inhaled agents, such as sevoflurane. It has useful analgesic properties, unlike the other agents used today, and its inclusion reduces the concentration of other agents required to maintain an adequate depth of anaesthesia for surgery.

In particular, its low solubility in body tissues gives it a unique pharmacokinetic profile, with rapid washin and washout from the body. It has been shown to have a similar effect on the speed of uptake of accompanying agents like sevoflurane (the "second gas effect"), which have much slower pharmacokinetics. A recent study by us suggested that this promotes faster and smoother onset of anaesthesia, as measured using the standard monitor of depth of anaesthesia (the BIS monitor). This finding requires confirmation prospectively in a larger group of patients. The investigators further hypothesise that a similar effect also exists on washout of sevoflurane at the end of the procedure, promoting quicker recovery (emergence) from anaesthesia. This has never been previously demonstrated. This information will help better define the place of nitrous oxide in achieving optimal outcomes in modern anaesthetic practice. The investigators propose to conduct a simple study to measure the effects of nitrous oxide washin and washout on exhaled concentrations of accompanying sevoflurane during both induction of anaesthesia and emergence, and identify any accompanying effect on the rate of change in depth of anaesthesia using BIS. The investigators hypothesise that the rate of fall of exhaled sevoflurane concentration at the end of anaesthesia will be more rapid in the group of patients breathing a gas mixture containing nitrous oxide, and that the rate of fall of BIS on induction and the rate of rise of BIS on emergence will be faster in the nitrous oxide group.

Trial website

https://clinicaltrials.gov/study/NCT01092923

Trial related presentations / publications

Public notes

Contacts

Principal investigator

Name

Phil Peyton, MBBS

Address

Austin Health

Country

Phone

Fax

Contact person for public queries

Name

Address

Country

Phone

Fax

Contact person for scientific queries

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

No documents have been uploaded by study researchers.

Results are available at https://clinicaltrials.gov/study/NCT01092923

Trial Review

Registering a new trial?

For full trial details, please see the original record at https://clinicaltrials.gov/study/NCT01092923