Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12625001110471
Ethics application status
Approved
Date submitted
26/09/2025
Date registered
13/10/2025
Date last updated
13/10/2025
Date data sharing statement initially provided
13/10/2025
Type of registration
Prospectively registered

Titles & IDs
Public title
A study to assess tissue health in patients undergoing orthopaedic surgery using a surgical humidification system
Scientific title
Wound Assessment and Response of Muscle Tissue with HumiGard™ (WARMTH) in Orthopaedic Surgery: A Randomised Controlled Pilot Trial
Secondary ID [1] 315403 0
CIA-365
Universal Trial Number (UTN)
U1111-1328-9993
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Patients undergoing posterior spine surgery 338981 0
Tissue health 338982 0
Condition category
Condition code
Surgery 335262 335262 0 0
Surgical techniques
Musculoskeletal 335379 335379 0 0
Other muscular and skeletal disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This randomised, single-blinded, controlled pilot study aims to evaluate the effectiveness of the HumiGard™ Surgical Humidification (Air) System in preserving tissue health during open orthopaedic spinal surgery.

The HumiGard™ (Air) System (Fisher and Paykel Healthcare Ltd, Auckland, NZ) is an intraoperative medical device designed to support the maintenance of patient temperature and tissue hydration during open orthopaedic surgery. It delivers warm, humidified medical-grade air directly to the surgical site via a soft diffuser suitable for incisions up to 26 cm. The diffuser is positioned over the incision to ensure consistent coverage of warm, humidified air across the surgical wound.

For this study, the device will be set up for all participants undergoing open spinal surgery. Immediately prior to surgery, the participants will be randomly assigned to one of two groups:

Arm 1 – HumiGard ON group: The device will be activated during surgery.
Arm 2 – HumiGard OFF group: The device will be set up but not turned on.

Tissue health will be assessed through the intraoperative collection of muscle tissue biopsies (no larger than 5x5x5 mm) at pre-determined timepoints. Biopsies will be taken by the operating surgeon using standard sterile techniques and will not alter the planned surgical procedure.

The anticipated duration of the HumiGard use is up to 3 hours from the first incision until wound closure. The operating surgeon will attach the diffuser to the surgical site for all participants and the theatre nurse will either turn HumiGard on or leave HumiGard off depending on the participants randomisation.

Adherence to the intervention will be monitored by verifying the device's activation status via its control panel and recording the duration of use in the data collection report.

The HumiGard™ System is approved for use in open orthopaedic surgery by regulatory authorities in Australia (TGA), New Zealand (Medsafe), and Canada (Health Canada),
Intervention code [1] 332050 0
Treatment: Devices
Comparator / control treatment
In the control group (HumiGard OFF group), the HumiGard™ Surgical Humidification (Air) System will be set up but remain inactive. The anticipated duration of surgery is up to 3 hours, from the first incision until wound closure, consistent with the intervention group.

Muscle tissue biopsies will be collected using the same procedures and timepoints as the intervention group. All other aspects of the surgery will follow standard hospital practice for open spinal surgery.

To ensure adherence to the control settings, the device’s inactive status will be verified via the control panel at the start and end of the procedure. The duration of device setup (without activation) will be recorded in the data collection report. No additional warming or humidification interventions will be introduced beyond standard care.
Control group
Active

Outcomes
Primary outcome [1] 342866 0
Histological assessment of the surgical wound tissue health
Timepoint [1] 342866 0
Muscle tissue biopsies will be obtained at the following time points: Baseline (once the wound has been dissected and retracted), 60, 120 and 180 minutes after knife to skin. The 180 minutes samples will only be taken if the surgery duration is 180 minutes or longer
Secondary outcome [1] 452469 0
There is no secondary outcome in this study
Timepoint [1] 452469 0
not applicable as there is no secondary outcome included

Eligibility
Key inclusion criteria
1- Patients undergoing primary elective posterior spinal surgery lasting at least 120 minutes
2- Patients aged 22 years and older
3- Patients able to provide written informed consent
Minimum age
22 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Individuals are excluded from participating in this study if:

1- Surgical procedure requires incision length greater than 260mm
2- Surgical procedure requires multiple incisions
3- Patient is undergoing a revision spinal surgery procedure

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Concealment will be achieved using sealed opaque envelopes opened by the research team at the time of surgery setup
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomisation list will be generated by an online tool
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s


Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
1/12/2025
Actual
Date of last participant enrolment
Anticipated
31/12/2026
Actual
Date of last data collection
Anticipated
31/12/2026
Actual
Sample size
Target
20
Accrual to date
Final
Recruitment outside Australia
Country [1] 27374 0
New Zealand
State/province [1] 27374 0
Hamilton

Funding & Sponsors
Funding source category [1] 319992 0
Commercial sector/Industry
Name [1] 319992 0
Fisher and Paykel Healthcare Ltd.
Country [1] 319992 0
New Zealand
Primary sponsor type
Commercial sector/Industry
Name
Fisher and Paykel Healthcare Ltd.
Address
Country
New Zealand
Secondary sponsor category [1] 322575 0
None
Name [1] 322575 0
Address [1] 322575 0
Country [1] 322575 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 318530 0
Northern B Health and Disability Ethics Committee 
Ethics committee address [1] 318530 0
Ethics committee country [1] 318530 0
New Zealand
Date submitted for ethics approval [1] 318530 0
26/08/2025
Approval date [1] 318530 0
24/09/2025
Ethics approval number [1] 318530 0

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 144486 0
A/Prof Joseph Baker
Address 144486 0
Orthopaedics Department, Waikato Hospital 183 Pembroke Street, Waikato Hospital, Hamilton, 3204
Country 144486 0
New Zealand
Phone 144486 0
+64 7 8398899
Fax 144486 0
Email 144486 0
[email protected]
Contact person for public queries
Name 144487 0
Smitha Nair
Address 144487 0
Fisher and Paykel Healthcare, 15 Maurice Paykel Place East Tamaki, Auckland 2013,
Country 144487 0
New Zealand
Phone 144487 0
+64 220123527
Fax 144487 0
Email 144487 0
[email protected]
Contact person for scientific queries
Name 144488 0
Smitha Nair
Address 144488 0
Fisher and Paykel Healthcare, 15 Maurice Paykel Place East Tamaki, Auckland 2013,
Country 144488 0
New Zealand
Phone 144488 0
+64 220123527
Fax 144488 0
Email 144488 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No


What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.