1. Inadvertent perioperative hypothermia
Implementing NICE guidance
ABOUT THIS PRESENTATION:
This presentation has been written to help you raise awareness of the NICE clinical guideline on inadvertent perioperative hypothermia. This guideline has been written for healthcare practitioners who care for adults undergoing elective and emergency surgery (including surgery for trauma), under general and/or regional anaesthesia in secondary and tertiary care settings.
The guideline is available in a number of formats. You can download these from the NICE website or order printed copies of the quick reference guide by calling NICE publications on or sending an to Quote reference number N1557.
You should hand out copies of the quick reference guide at your presentation so that your audience can refer to it during the presentation.
You can add your own organisation’s logo alongside the NICE logo. We have included notes for presenters to help highlight key points to raise in your presentation and to provide supplementary information to the slides. Where necessary, the recommendation will be given in full.
DISCLAIMER
This slide set is an implementation tool and should be used alongside the published guidance. This information does not supersede or replace the guidance itself.
2008
NICE clinical guideline 65

2. What this presentation covers
Background
Definitions
Key priorities for implementation
Costs and savings
Discussion
Find out more
NOTES FOR PRESENTERS:
In this presentation we will start by providing background for the guideline and why it is important.
The guideline covers: adults (age 18 years and over) undergoing elective or emergency surgery (including surgery for trauma), under general or regional (central neuraxial block) anaesthesia.
The guideline does not cover: children and young people under 18 years of age; pregnant women; patients who have been treated with therapeutic hypothermia; patients undergoing operative procedures under local anaesthesia; patients with severe head injuries resulting in impaired temperature control.
The NICE guideline contains 10 key priorities for implementation which you can find in your quick reference guide.
The key priorities for implementation cover the following phases of perioperative care:
Preoperative phase
Intraoperative phase
Post operative phase
Costs and savings that are likely to be incurred in implementing the guideline are summarised, followed by a suggested list of questions to help prompt discussion.
Information on how to find out more about the support provided by NICE is given at the end of this presentation.

3. Background
Surgical patients are at risk of developing hypothermia at any stage of the perioperative pathway.
Inadvertent perioperative hypothermia is a common but preventable complication, which is associated with poor outcomes for patients.
NOTES FOR PRESENTERS:
Key points to raise:
If the perioperative team do not manage the risk of perioperative hypothermia throughout the perioperative patient pathway, as many as 70% of patients undergoing routine surgery may be hypothermic on admission to the recovery room.
Hypothermia needs to be prevented due to the potential impact both on the patient and on resources.
If hypothermia does develop, patients can experience shivering and thermal discomfort.
Poor outcomes for patients include an increased risk of wound infection and morbid cardiac events, including ischaemia.
Hypothermia may also increase the post-anaesthetic recovery time and the total length of hospital stay, which can have an adverse impact on theatre throughput and surgical list management.
Additional information:
During the first 30 to 40 minutes of anaesthesia, a patient’s temperature can drop to below 35.0°C. Reasons for this include loss of the behavioural response to cold and the impairment of thermoregulatory heat-preserving mechanisms under general or regional anaesthesia, anaesthesia-induced peripheral vasodilation (with associated heat loss), and the patient getting cold while waiting for surgery on the ward or in the emergency department.

4. Definitions Preoperative - 1 hour before induction of anaesthesia
Intraoperative - the total anaesthesia time
Postoperative - 24 hours after entry into the
recovery area in the theatre suite
Hypothermia - a patient core temperature of
below 36.0°C.
Comfortably warm - the expected normal
temperature range of adult patients
Temperature - used to denote core temperature
NOTES FOR PRESENTERS:
Key points to raise:
It is important that the audience understand the terms used in this presentation in order to obtain a good understanding of the intentions of this clinical guideline:
Hypothermia is when a patient has a core temperature of below 36.0°C
Comfortably warm - the expected normal temperature range of adult patients (between 36.5°C and 37.5°C) This term is used in the recommendations relating to both the preoperative and postoperative phases.
Temperature - used to denote core temperature.
The perioperative pathway is divided into three phases:
Preoperative - when the patient is prepared for surgery on the ward or in the emergency department.
Intraoperative – the total anaesthesia time
Postoperative – this includes the transfer to and time spent on the ward.

5. Advice for patients
Patients (and their families and carers) should be informed before and on admission that:
staying warm before surgery will lower the risk of postoperative complications
the hospital environment may be colder than their own home
they should bring additional clothing to help them keep comfortably warm
they should tell staff if they feel cold at any time during their hospital stay.
NOTES FOR PRESENTERS:
Key points to raise:
This is the first of the 10 key priorities for implementation.
Additional clothing includes items such as a dressing gown, a vest, warm clothing and slippers.
Patients will need to be provided with this information in advance of admission.
Recommendation in full:
Patients (and their families and carers) should be informed that:
staying warm before surgery will lower the risk of postoperative complications
the hospital environment may be colder than their own home
they should bring additional clothing, such as a dressing gown, a vest, warm clothing and slippers, to help them keep comfortably warm
they should tell staff if they feel cold at any time during their hospital stay. [1.1.1 NICE guideline]

6. Measuring patient temperature
When using any device to measure patient temperature, healthcare professionals should:
be aware of, and carry out, any adjustments that need to be made in order to obtain an estimate of core temperature from that recorded at the site of measurement
be aware of any such adjustments that are made automatically by the device used.
NOTES FOR PRESENTERS:
Key points to raise:
This is the next key priority. A further recommendation from the guideline (not a key priority)
is as follows:
When using any temperature recording or warming device at any stage during the
perioperative care pathway, healthcare professionals should:
be trained in their use
maintain them in accordance with manufacturers’ and suppliers’ instructions
comply with local infection control policies [1.1.2, NICE guideline]
Key recommendation in full: as shown on slide [1.1.3, NICE guideline]

7. Preoperative phase
Each patient should be assessed for their risk of inadvertent perioperative hypothermia and potential adverse consequences before transfer to the theatre suite.
NOTES FOR PRESENTERS:
Key points to raise:
Assessing the patient’s risk of inadvertent perioperative hypothermia might take place in A&E, assessment units, preoperative assessment facilities or on the ward
Patients at higher risk of perioperative hypothermia are discussed in the next slide.
Additional information:
The patient’s temperature should be measured and documented in the hour before they leave the ward or emergency department [1.2.4, NICE guideline]
Healthcare professionals should ensure that patients are kept comfortably warm while waiting for surgery by giving them at least one cotton sheet plus two blankets, or a duvet [1.2.2, NICE guideline]
Special care should be taken to keep patients comfortably warm when they are given premedication (for example, nefopam, tramadol, midazolam or opioids) [1.2.3, NICE guideline]
Key recommendation in full:
Each patient should be assessed for their risk of inadvertent perioperative hypothermia and potential adverse consequences before transfer to the theatre suite. Patients should be managed as higher risk if any two of the following apply: Discussed in the next slide
ASA grade II to V (the higher the grade, the greater the risk)
preoperative temperature below 36.0°C (and preoperative warming is not possible because of clinical urgency)
undergoing combined general and regional anaesthesia
undergoing major or intermediate surgery
at risk of cardiovascular complications. [1.2.1, NICE guideline]

8. Patients at higher risk of perioperative hypothermia
Some patients are at higher risk of inadvertent perioperative hypothermia; they should be managed accordingly if any two of the following apply:
ASA grade II to V
preoperative temperature below 36.0°C
undergoing combined general and regional
anaesthesia
undergoing major or intermediate surgery
at risk of cardiovascular complications.
NOTES FOR PRESENTERS:
Key points to raise:
The higher the ASA grade, the greater the risk
Patients who have a temperature of below 36.0°C should normally be warmed preoperatively; however, this is not always possible because of clinical urgency.
Additional information:
ASA (American Society of Anesthesiologists) Physical Status Classification System
Class I A normal healthy patient
Class II A patient with mild systemic disease
Class III A patient with severe systemic disease
Class IV A patient with severe systemic disease that is a constant threat to life
Class V A moribund patient who is not expected to survive without the operation
Class VI A declared brain-dead patient whose organs are being removed for donor purposes

9. Preoperative warming
If the patient’s temperature is below 36.0°C in the hour before they leave the ward or emergency department:
forced air warming should be started preoperatively on the ward or in the emergency department (unless there is a need to expedite surgery because of clinical urgency)
forced air warming should be maintained throughout the intraoperative phase.
NOTES FOR PRESENTERS:
Key points to raise:
Examples of clinical urgency are bleeding and critical limb ischaemia.
Other related recommendations are:
The patient’s temperature should be measured and documented in the hour before they leave the ward or emergency department [1.2.4, NICE guideline].
The patient’s temperature should be 36.0°C or above before they are transferred from the ward or emergency department (unless there is a need to expedite surgery because of clinical urgency) [1.2.6, NICE guideline]
Additional information:
On transfer to the theatre suite:
the patient should be kept comfortably warm
the patient should be encouraged to walk to theatre where appropriate [1.2.7, NICE guideline]
Recommendation in full:
If the patient’s temperature is below 36.0°C:
forced air warming should be started preoperatively on the ward or in the emergency department (unless there is a need to expedite surgery because of clinical urgency, for example bleeding or critical limb ischaemia)
forced air warming should be maintained throughout the intraoperative phase. [1.2.5, NICE guideline]

10. Intraoperative phase
The patient’s temperature should be measured and documented before induction of anaesthesia and then every 30 minutes until the end of surgery.
Induction of anaesthesia should not begin unless the patient’s temperature is 36.0°C or above.
NOTES FOR PRESENTERS:
Key points to raise:
Surgery should not begin if the patient’s temperature is below 36.0°C unless there is a need to expedite surgery because of clinical urgency, for example bleeding or critical limb ischaemia.
A further recommendation is:
Standard critical incident reporting should be considered for any patient arriving at the theatre suite with a temperature below 36.0°C [1.3.2, NICE guideline]
Additional information:
Other related recommendations for the intraoperative phase are:
In the theatre suite:
the ambient temperature should be at least 21°C while the patient is exposed
once forced air warming is established, the ambient temperature may be reduced to allow better working conditions.
using equipment to cool the surgical team should also be considered [1.3.4, NICE guideline]
The patient should be adequately covered throughout the intraoperative phase to conserve heat, and exposed only during surgical preparation [1.3.5, NICE guideline]
Key recommendations in full: as shown on slide [1.3.1, NICE guideline]
Induction of anaesthesia should not begin unless the patient’s temperature is 36.0°C or above (unless there is a need to expedite surgery because of clinical urgency, for example bleeding or critical limb ischaemia). [1.3.3]

11. Intraoperative warming
The following patients should be warmed intraoperatively from induction of anaesthesia using a forced air warming device:
those at higher risk of inadvertent perioperative hypothermia and who are having anaesthesia for less than 30 minutes
those who are having anaesthesia for longer than 30 minutes
NOTES FOR PRESENTERS:
Key points to raise:
Patients at ‘higher risk’ of perioperative hypothermia have been previously discussed on slide 8.
Related recommendation:
The temperature setting on forced air warming devices should be set at maximum and then adjusted to maintain a patient temperature of at least 36.5°C [1.3.9, NICE guideline]
Key recommendations in full:
Patients who are at higher risk of inadvertent perioperative hypothermia and who are having anaesthesia for less than 30 minutes should be warmed intraoperatively from induction of anaesthesia using a forced air warming device [1.3.7, NICE guideline].
All patients who are having anaesthesia for longer than 30 minutes should be warmed intraoperatively from induction of anaesthesia using a forced air warming device [1.3.8, NICE guideline]

12. Warming intravenous fluids
Intravenous fluids (500 ml or more) and blood products should be warmed to 37°C using a fluid warming device.
NOTES FOR PRESENTERS:
Key point to raise:
Related recommendation:
All irrigation fluids used intraoperatively should be warmed in a thermostatically controlled cabinet to a temperature of 38–40°C [1.3.10, NICE guideline]
Key recommendation in full:
As shown on slide [1.3.6, NICE guideline]

13. Postoperative phase
The patient’s temperature should be measured and documented on admission to the recovery room and then every 15 minutes
Ward transfer should not be arranged unless the patient’s temperature is 36.0°C or above.
If the patient’s temperature is below 36.0°C, they should be actively warmed using forced air warming until they are discharged from the recovery room or until they are comfortably warm
NOTES FOR PRESENTERS:
Key points to raise:
Once patients are back on the ward, they should be kept comfortably warm (see additional information).
Additional information:
Related recommendations:
Patients should be kept comfortably warm when back on the ward.
Their temperature should be measured and documented on arrival at the ward.
Their temperature should then be measured and documented as part of routine 4‑hourly observations.
They should be provided with at least one cotton sheet plus two blankets, or a duvet [1.4.2, NICE guideline]
If the patient’s temperature falls below 36.0°C while on the ward:
they should be warmed using forced air warming until they are comfortably warm
their temperature should be measured and documented at least every 30 minutes during warming [1.4.3, NICE guideline]
Key recommendation in full:
As shown on slide [1.4.1, NICE guideline]

14. Costs and savings per 100,000 population
Recommendations with significant costs
Costs
(£ per year)
Increased use of forced air warming blankets
43,000
Increased warming of IV fluids and blood products
23,000
Estimated cost of implementation
66,000
Recommendations with significant savings
Savings
Expected reduction in surgical site infections*
–43,000
Estimated annual net cost of implementation
ADAPTING THIS SLIDE FOR LOCAL USE:
We are aware that local factors such as incidence and baseline can vary considerably when compared with the national average. NICE has provided a costing template for you to calculate the financial impact this guideline will have locally. We encourage you to calculate the local impact of this guideline by amending the local variations in the template such as incidence, baseline and uptake. You can then remove the national figures from the table and replace them with your local figures to present to your colleagues.
NOTES FOR PRESENTERS:
The information on this slide has been extracted from the NICE costing report, which has been provided by NICE to support implementation of this guidance. It was developed after careful consideration of the available data and by working closely with the guideline developers and other people in the NHS. It is not NICE guidance. Assumptions used in this report are based on assessment of the national average and it is recognised that local practice or circumstances may differ from this. The costs published in this report are estimates only and are not to be taken as the Institute's view of desirable, or maximum or minimum figures.
NICE has also provided a costing template to help calculate the local costs associated with implementing this guideline. The costs per 100,000 population are summarised in the table. It is recognised that implementation of the recommendations may take place over a number of years.
Implementation of the guidance may also result in savings through a reduction in morbid cardiac events and blood transfusions. These savings have not been quantified in the costing report, but may be identified at a local level.
In addition, compliance with NICE guidance is one of the criteria indicating good risk reduction strategies, and in combination with meeting other criteria could lead to a discount on contributions to the NHS Litigation Authority schemes, including the clinical negligence scheme for trusts (CNST).
For further information please refer to the costing template and costing report for this guidance on the NICE website.
* Additional savings have been identified that cannot be quantified – full details in the costing report.

15. Discussion
Which key areas of local practice differ from the guideline?
To ensure effective implementation:
what equipment is needed?
what are staff training needs?
What will the impact be on the average length of patient stay if the guideline is implemented fully?
How should Risk and Safety Managers be involved in the implementation of the guideline?
NOTES FOR PRESENTERS:
These questions are suggestions that have been developed to help provide a prompt for a discussion at the end of your presentation – please edit and adapt these to suit your local situation.

16. Find out more Visit www.nice.org.uk/cg065 for: Other guideline formats
Costing report and template
Audit support
Implementation advice
NOTES FOR PRESENTERS:
The guideline is available in a number of formats.
The quick reference guide – which summarises the guidance.
The NICE guideline – which includes all of the recommendations in full.
The full guideline – which includes all of the evidence and rationale.
‘Understanding NICE guidance’ – a version for patients and carers.
You can download these from the NICE website or order printed copies of the quick reference guide and ‘Understanding NICE guidance’ by calling NICE publications on or by sending an to Quote reference number N1557 for the quick reference guide and N1558 for ‘Understanding NICE guidance’. You may want to hand out copies of the quick reference guide at your presentation so that your audience can refer to it.
NICE has developed tools to help organisations implement this guideline, which can be found on the NICE website.
Costing tools – a costing report gives the background to the national savings and costs associated with implementation, and a costing template allows you to estimate the local costs and savings involved.
Audit support – assists NHS trusts to determine how well they meet NICE recommendations.
Implementation advice – gives details of how to put the guideline into practice and national initiatives that support this locally.