On Thursday 18th May the National Institute for Health and Care Excellence (NICE) released the updated head injury guidelines: assessment and early management [NG232]
There have been three head injury guidelines in 2003, 2007 and 2014. The second guideline in 2007 was associated with a reduced admitted TBI mortality rate after specialist care was recommended for severe TBI. The improvement was solely observed in patients aged 16-64 years. The 2014 (CG 176) changed clinical practice in the UK. A Head CT scan for all patients with head injury on warfarin even if there are no signs of traumatic brain injury (TBI) was the key recommendation. Now the question is how will the latest iteration change clinical practice.
Please take the time to read the guidelines in full. No doubt Emergency Departments and ambulance services up and down the country will be pouring over the recommendations. There will be a period of adjustment and refinement. So, here are the headlines of the new NICE head injury guidelines and what we think they might mean for our ED practice.
What are the key changes for adults?
- Transport people who have sustained a head injury directly to an MTC or TU that has the age-appropriate resources to further resuscitate them, and to investigate and initially manage multiple injuries (1.3.13).
- For people with a head injury and a GCS score of 12 or less who are not thought to have active extracranial bleeding, consider a 2g IV bolus injection of TXA for people 16 and over. Give the TXA as soon as possible, within 2 hours, in prehospital or hospital setting and before imaging (1.3.17)
- Do not refer people who have had a head injury for neuroimaging by direct access from the community (1.3.19).
- Consider or suspect abuse, neglect or other safeguarding issues as a contributory factor to, or cause of, a head injury (1.4.12).
- For people who have sustained a head injury and have no other indications for a CT head scan, but are on anticoagulant treatment (including vitamin K antagonists, direct-acting oral anticoagulants, heparin or low molecular weight heparins) or antiplatelet treatment (excluding aspirin monotherapy), consider doing a CT head scan:
- Within 8 hours of the injury (for example, if it is difficult to do a risk assessment or if the person might not return to the emergency department if they have signs of deterioration) or
- Within the hour if they present more than 8 hours after the injury (1.5.13)
- Be aware that any severity of head injury can cause pituitary dysfunction. This may present immediately, hours, weeks or months after the injury (1.9.6).
- In people admitted to hospital with a head injury who have persistently abnormal low sodium levels or low blood pressure, consider investigations for hypopituitarism (1.9.7).
- Ensure that people with pre-injury cognitive impairment (for example, dementia or a learning disability) and people returning to a custodial setting are supervised and monitored. Also, make sure that arrangements are in place should there be any signs of deterioration (1.10.6).
- Refer people with a head injury to investigate its causes and manage contributing factors, if appropriate. This could include, for example, referral for a falls assessment or to safeguarding services (1.10.13).
- Isolated simple linear closed non depressed skull fracture – in people who are not on anticoagulant or antiplatelet medication unlikely to be clinically significant and does not require admission (1.9.1)
- Indicators for imaging the cervical spine: CT is recommended for medium risk in adults (no role for plain x-rays, except medium risk aged < 16).
What are the key changes for children?
- Addition of bleeding/clotting disorder as risk criteria for head CT within an hour following a head injury (1.5.11)
- Children on anticoagulants may need CT within 8 hours of injury (1.5.13)
- For people under 16 with a head injury and a GCS score of 12 or less who are not thought to have active extracranial bleeding, consider a 15 mg/kg to 30 mg/kg (up to a maximum of 2 g) IV bolus injection of TXA. Give the TXA as soon as possible, within 2 hours, in prehospital or hospital setting and before imaging (1.3.17)
What are the implications for practice?
I think there are implications in two areas: 1) TXA dosing and timing; 2) broadening to antiplatelets, alongside anticoagulants as an indication for head CT, as well as at the same time moving the recommendation to a ‘consider,’ and an opportunity for shared decision making between clinician and patient and; 3) early diagnosis of hypopituitarism.
What’s new for TXA in isolated head injuries?
The new TXA dosing of 2g IV bolus without being followed by an infusion for 8 hours and given within 2 hours for isolated head injury will have implications for our colleagues working in the pre-hospital environment. How quickly will this be reflected in JRCALC and SOPs in the ambulance service? For us in ED it will be a change of dosing for adults and children that will have to be reflected in SOPs. It is worth remembering this does not change practice in major trauma with multiple injuries, which remains 1g bolus within 3 hours and 1g infusion over 8 hours.
To scan or not to scan if on anticoagulants or antiplatelets?
It is interesting that the consideration of scanning in anticoagulants could lead to a reduction in head CT scans. However, this may be counter-balanced by an increase in head CT scans as we are now considering antiplatelets (minus aspirin monotherapy). Despite this, it does offer an opportunity to have discussions with patients and shared decision making whether a head CT scan is necessary. What patients that are on warfarin, DOACs or antiplatelets with a GCS of 15 might we consider scanning, but not doing it? What are the important factors in the history we need to think about? NICE say if they don’t have LOC, amnesia, have a GCS 15 and no other indications they can be risk assessed. In the AHEAD study looking at warfarin and head injury, amnesia and LOC were significant risks of having an adverse outcome. What will be your threshold for scanning in these patients?
What’s the deal with hypopituitarism?
The guidelines also highlight the importance of knowing even mild head injury can cause hypopituitarism. It can occur straight away or months down the line. However, it is a difficult condition to diagnose due to the variability in symptoms. Key points are around investigation for patients admitted with head injury if they have hyponatraemia or hypotension and those presenting after head injuries with persistent symptoms to primary care. We can envisage there will be a cohort that also attends ED with persistent symptoms and we should try and keep it within our differential.
What further research is required?
As is the case with all NICE guidelines it contains recommendations for research. Here are some you might be interested in:
- Indications for admission in people with mild head injury and a confirmed abnormality on a CT scan
- Using biomarkers for predicting acute post-traumatic brain injury complications
- Indications for imaging for people with a history of recurrent head injuries
- Risk of bleeding for people with a pre-injury coagulopathy
- Indications for imaging for people with a pre-injury cognitive impairment
- Whether we should bypass nearby hospitals to take patients to a neurosciences centres
- Indications for selecting people for imaging when they present more than 24 hours after a head injury
- Timing of testing for hypopituitarism
- Using biomarkers and MRI for predicting postconcussive syndrome
What is the bottom line?
Professor Fiona Lecky, topic advisor for the NICE committee provided a useful summary of what as clinicians we need to know:
- An IV TXA bolus within 2 hours of injury can be considered life-saving in people with suspected moderate or severe traumatic brain injury – even when no extracranial bleeding event is evident.
- Shared decision-making can now inform a decision not to conduct a CT head scan in people taking anticoagulant or antiplatelet medication (not aspirin monotherapy) if there are no signs or symptoms of traumatic brain injury.
- Evidence suggests that even apparently mild head injury can lead to significant long-term consequences such as hypopituitarism.
So there you have it, a whistle stop tour of the key changes to the NICE head injury guidelines and their possible implications in clinical practice. Will these guidelines change discussions with colleagues? Iain Beardsell tweet suggests it already has 😀
Thanks to Professor Fiona Lecky for her input into this blog.
1 thought on “NICE Head Injury Guidelines 2023: Now who do we scan?”
Thanks for the summary ! It seems that this topic is a hot one recently
for instance Justin Morgenstern discouraging from using the Canadian CT head rule https://first10em.com/canadian-ct-head-rule/amp/ based on an older Ian Stiell study
At least you avoided the whole S100B problem and “all platelets + >65 y = CT scan” that we can’t seem to get rid off in Scandinavia when it comes to head trauma (https://bmcemergmed.biomedcentral.com/articles/10.1186/s12873-018-0193-2) . I like that there’s room for shared decision making in the new NICE algorithm
My guess is that this is not validated in any studies? Seen in the light of Morgensterns post, it seems like we should probably be doing just that with these CDRs (in general) and head CT algorithms in particular , as even the best studied (Canadian head CT) seems to be no better (and maybe even harmful) compared to clinical judgement