Condition category
Signs and Symptoms
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
Hypothermia (when body temperature drops below normal levels of 36°C) can be common after surgery and can effect patients’ recovery, such as delaying wound healing and potential for increased surgical site infections plus an increased requirement for blood transfusion. Forced Air Warming (the process of blowing warm air through an inflatable blanket over the patient) is currently recommended by the National Institute Clinical Excellence (NICE) for patients experiencing hypothermia after surgery (post-operative). As Forced Air Warming requires dedicated equipment and the availability of electricity alternative methods which are just as effective in warming patients have been are sought. The Orve+ Wrap is a new blanket available for warming patients but its clinical effectiveness has yet to be determined in the post-operative period. The aim of this study is to find out how effective the Orve+ Wrap warming blanket is compared to forced air warming blankets in patients who become hypothermic after surgery.

Who can participate?
Adult patients who have planned orthopeadic surgery scheduled.

What does the study involve?
After surgery when participants are admitted to the recovery area a temperature a sensor is placed on their forehead to constantly measure of their temperature. If this temperature is less than 36°C, participants are given a blanket that either blows warm air over patients (Forced Air Warming or a blanket that insulates patients Orve+ Wrap. The treatment that patients receive is chosen randomly by a computer programme with equal chance of getting each blanket. Participants then have their temperature monitored every 10 minutes until they leave the recovery area to assess the effectiveness of the blanket they used.

What are the possible benefits and risks of participating?
It is unknown as to whether participants will benefit by taking part, however participants could help identify the most effective way of managing patients’ temperatures in the initial post-operative period and therefore improve the comfort and care in future patients. There are no perceived risks involved with taking part. However, previous research investigating post-surgery hypothermia has shown a link between being cold and an increased risk of infections at the site of surgery. All participants will be closely monitored after surgery for signs of infection and appropriate treatment will be commenced if their surgical team believes it is required.

Where is the study run from?
Castle Hill Hospital (UK)

When is the study starting and how long is it expected to run for?
October 2014 to October 2017

Who is funding the study?
Orvec International Ltd. (UK)

Who is the main contact?
Mr Neil Smith

Trial website

Contact information



Primary contact

Mr Neil Smith


Contact details

Hull and East Yorkshire Hospitals NHS Trust
Hull Royal Infirmary
Anlaby Road
United Kingdom
+44 1482 674457

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

An open label, randomised controlled trial on the effectiveness of the Orve+ wrap blanket Vs forced air warming in restoring normothermia in the post anaesthetic Care Unit



Study hypothesis

The aim of this study is to look at how effective the Orve+ Wrap warming blanket is compared to forced air warming blankets in patients who become hypothermic (< 3 6°c) after surgery.

Ethics approval

Leeds West Research Ethics Committee, 25/08/2016, ref: 16/YH/0097

Study design

Randomised; Interventional; Design type: Treatment, Device

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

See additional files


Specialty: Anaesthesia, perioperative medicine and pain management, Primary sub-specialty: Anaesthesia, Perioperative Medicine and Pain Management; UKCRC code/ Disease: Injuries and Accidents/ Complications of surgical and medical care, not elsewhere classified


Participants are randomised to one of two groups electronically using sealed envelope™ (London, UK) on a 1:1 basis with stratification for Spinal and general anaesthesia and for age under 65 years or 65 years or greater.

Control arm: Patients will receive Forced Air Warming at the highest setting deemed clinical suitable.

Group 2: Patients will receive Orve+ Wrap for the duration of their Post Anaesthetic Care Unit stay or until the patient reaches normothermia (36.5°c) beforehand.

Patients in both groups will be followed up until hospital discharge

Intervention type



Drug names

Primary outcome measure

Mean temperature difference at 60 minutes post PACU admission using the zero heat flux thermometry Spot On (3m, Bracknell, UK)

Secondary outcome measures

No secondary outcome measures

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Patients aged >18
2. Planned elective or expedited orthopeadic surgery
3. Able to provide informed consent

Participant type


Age group




Target number of participants

Planned Sample Size: 128; UK Sample Size: 128

Participant exclusion criteria

1. Lacks capacity to provide informed consent.
2. Current participation in an interventional research trial.
3. Unable to understand english both written and verbal.
4. Patients who are known to be pregnant.
5. Emergency/urgent surgery Known thyroid dysfunction

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Castle Hill Hospital
Castle Road
HU16 5JQ
United Kingdom

Sponsor information


Hull and East Yorkshire Hospitals NHS Trust

Sponsor details

Hull Royal Infirmary
Anlaby Road
United Kingdom

Sponsor type

Hospital/treatment centre



Funder type


Funder name

Orvec International Ltd.

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Plans are for publication in a peer reviewed journal with a focus on anaesthesia or perioperative management.

IPD Sharing plan:
The current data sharing plans for the current study are unknown and will be made available at a later date.

Intention to publish date


Participant level data

To be made available at a later date

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

08/01/2019: The following changes were made to the trial record: 1. The recruitment end date was changed from 17/04/2017 to 20/11/2018. 2. The overall trial end date was changed from 17/10/2017 to 30/11/2018. 3. The intention to publish date was changed from 31/07/2018 to 31/03/2019.