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Trial registered on ANZCTR

Registration number
Ethics application status
Not yet submitted
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
Altered breathing with postoperative pain relief
Scientific title
A randomised phase 3/4 study to compare the postoperative effects of morphine versus tramadol/ketamine/parecoxib analgesia on respiratory obstructions, apnoeas and oxygen desaturation.
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obesity 1733 0
Respiratory Depression 1734 0
Postoperative analgesia 1735 0
Condition category
Condition code
Diet and Nutrition 1825 1825 0 0
Respiratory 1826 1826 0 0
Pain management

Study type
Description of intervention(s) / exposure
A comparison of morphine with a combination of parecoxib, ketamine and tramadol for analgesia in the first 12 hours after surgery. The tramadol to be given by patient-controlled intravenous doses. Continuous recording of respiratory data for 12-18 hours after surgery in all patients.
Doses: tramadol 3mg/kg + 10mg bolus with 10min lockout, ketamine 0.3mg/kg iv + 0.1mg/kg/hr, parecoxib 40mg iv single dose.
Intervention code [1] 1692 0
Comparator / control treatment
Morphine analgesia in the first 12 hours after surgery. The morpine is given by patient-controlled intravenous doses. Continuous recording of respiratory data for 12-18 hours after surgery in all patients.Doses: morphine 1mg bolus with 5min lockout,
Control group

Primary outcome [1] 2558 0
Reduced number respiratory obstructions or desaturations.
Timepoint [1] 2558 0
Total for 12 hours to 0600hr on day after surgery.
Secondary outcome [1] 4404 0
Analgesia and side-effects
Timepoint [1] 4404 0
Average of verbal numeric pain scores for 12hr period to 0600hr, need for rescue analgesia.

Key inclusion criteria
Obese (BMI>29) patients or airway abnormality on preoperative anaesthesia examination.Likely to require postoperative morphine or equivalent analgesia.Postoperative overnight hospital stay.
Minimum age
18 Years
Maximum age
90 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Intrathoracic or upper-abdominal surgery. Previous adverse reaction to any study drugs including nausea or vomiting.

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation is not concealed.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
computer generated table
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Respiratory monitor 12hr recording analysed by researcher blinded to treatment group.
Phase 3 / Phase 4
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 1976 0
Name [1] 1976 0
Department of Anaesthesia and Pain Management, RMH
Address [1] 1976 0
Country [1] 1976 0
Primary sponsor type
Royal Melbourne Hospital
Secondary sponsor category [1] 1789 0
Name [1] 1789 0
Address [1] 1789 0
Country [1] 1789 0

Ethics approval
Ethics application status
Not yet submitted
Ethics committee name [1] 3672 0
Melbourne Health Research and Ethics Committee
Ethics committee address [1] 3672 0
Ethics committee country [1] 3672 0
Date submitted for ethics approval [1] 3672 0
Approval date [1] 3672 0
Ethics approval number [1] 3672 0

Brief summary
Many patients experience some degree of breathing difficulty after major surgery and breathing difficulties may be the basis for serious, but uncommon complications of anaesthesia and surgery. The use of sedatives and morphine-like drugs for the relief of pain, although very necessary, contributes to decreased breathing effort, pauses and obstruction. Patients with obstructive sleep apnoea (OSA) syndrome, associated with a history of snoring, observed pauses in breathing during sleep and daytime sleepiness, may be at especially high risk with anaesthesia. This syndrome is associated with obesity, and may be a partial cause for, many types of heart and lung disease. Specialized high-dependency postoperative care is advocated for these patients.
We are interested in patients who do not have a definite diagnosis of OSA or severe symptoms, but who do have a high body mass index (BMI) and some abnormal airway features that imply increased risk of obstruction. Such patients may make up to 20% of patients presenting for elective surgery at the RMH. An initial respiratory monitoring study in progress, suggests that patients with these risk factors have increased breathing difficulties and reduced blood oxygen in the period after surgery.
In the proposed study, patients who are considered to be at risk of breathing problems on the basis of questionnaires and examination prior to surgery, will be randomized to either standard opioid (morphine) pain relief for the first day after surgery or to a group where other pain relieving dugs (ketamine, parecoxib and tramadol) are used in an attempt to reduce opioid use while maintaining adequate pain relief. In both groups dugs will be used according to protocols approved by the Acute Pain Service at the Royal Melbourne Hospital.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 27795 0
Address 27795 0
Country 27795 0
Phone 27795 0
Fax 27795 0
Email 27795 0
Contact person for public queries
Name 10881 0
A/Prof Duncan Blake
Address 10881 0
Department of Anaesthesia and Pain Management
Royal Melbourne Hospital
Parkville VIC 3050
Country 10881 0
Phone 10881 0
+61 3 93427925
Fax 10881 0
Email 10881 0
Contact person for scientific queries
Name 1809 0
A/Prof Duncan Blake
Address 1809 0
Department of Anaesthesia and Pain Management
Royal Melbourne Hospital
Parkville VIC 3050
Country 1809 0
Phone 1809 0
+61 3 93427925
Fax 1809 0
Email 1809 0

No information has been provided regarding IPD availability
Summary results
No Results