JC: Lower GI bleeding guidance. St Emlyn’s

The management of the patient with apparent lower GI (gastro-intestinal) bleeding is, in my experience at least, somewhat variable. Unlike upper GI bleeding where the standards and expectations are reasonably well known^​1,2​, the lower GI bleed patient in the ED seems to be managed at the whim however might be on call that day. This combined with the well trodden turf wars about who admits (or does not admit) the patient means that these patients can be complex.

They can also be really, really sick……., or not, as the range of conditions stretches across a range of pathologies from simple haemorrhoids through to catastrophic bleeding from diverticular disease, cancer, vascular malformations and more.

In other words, it’s all a little complex and whilst variation and individualised care might be a good thing for some patients, I’m mindful that some guidance and agreed strategies for investigating and managing these patients is a good idea.

So, thanks to Michael for spotting a new guideline for the management of these patients in the Journal ‘Gut’^​3​. (Ed – this was also covered by The Breach blog back in May. If you’ve not checked out ‘The Breach then we’d recommend it as another EBM blog for EM https://the-breach.com/new-guidelines-on-lower-gi-bleeding/ ^​4​).

The paper^​3​ is currently open access so as we always say here at St Emlyn’s, go read the paper yourself and come to your own conclusions.

What kind of paper is this?

This is a consensus guideline based on experts from the British Association of Gastroenterology. In that respect this is not like a systematic review or meta-analysis where the data is king. Rather it is a collection of experts who have brought together their experience to interpret the evidence. This is common to many guideline development strategies, and indeed the authors have adhered to a guideline development structure^​5​, but as a critical appraisal exercise it is important to recognise that this may create bias in the conclusions.

The authors have reviewed a range of studies, blended this with their experience and opinions to deliver a series of consensus statements, and a resulting flow chart that might guide clinicians in the management of lower GI bleeds. As the paper covers both diagnostics and initial interventions it is very relevant to the EM community.

Who wrote the guidelines?

There are 17 authors from surgery, medicine, epidemiology, research and radiology. It does not looks as though there is any emergency medicine representation. The lead author has extensive experience and primary research in this area^​6​.

What are the main findings?

These are best described in the full open access paper and you should read them there. These are my summary points for those especially important to the emergency medicine community, together with some unanswered questions as Ed comments

1. Patients presenting with lower gastrointestinal bleeding (LGIB) should be stratified as unstable or stable (unstable defined as a shock index >1). (Ed – shock index is a blunt tool to assess shock – I think we can do better than simply the SBP and HR)
2. Stable bleeds should then be categorised as major or minor, using a risk assessment tool such as the Oakland score^​7​ (Ed – the Oakland score is apparently named after the first author of this study and was validated in fewer than 300 patients, of whom only 184 were discharged home and of which 5% had an unsafe discharge such as rebleeding, transfusion, Hct drop, death, readmission. That seems quite high to me. Other scores are available)
3. Patients who have stopped bleeding and who have an Oakland score ≤8 points, with no other indications for hospital admission can be discharged from the ED for urgent outpatient investigation (Ed – again look at the score^​8​. It is possible to get to below 8 with some strange combinations, but I suspect they would be rare and you can always override the score in a patient who gives significant concern)
4. Patients with a major bleed should be admitted to hospital for colonoscopy on the next available list. (Ed – yep, but consider when that is with current pressures and weekends etc.)
5. If a patient is haemodynamically unstable or has a shock index (heart rate/systolic BP) of >1 after initial resuscitation (Ed – this is not really well defined for me, what does after initial resuscitation mean exactly?) and/or active bleeding is suspected then CT angiography should be used to localise the site of blood loss before planning endoscopic or radiological therapy
6. If no bleeding sites is found on CT Angiography or colonoscopy and the patient has haemodynamic instability then consider that this may be an upper GI bleed with rapid transit of blood to the lower bowel.
7. Catheter angiography/embolisation should be performed as soon as possible after a positive CTA to maximise chances of success. In centres with a 24/7 interventional radiology service, this should be available within 60 min for haemodynamically unstable patients (Ed – what about those centres without on site 24/7 – should we transfer at this point? Could this be an ED-ED transfer process?)
8. Non surgical interventions should be tried first. Laparotomy rarely needed.
9. Transfusion thresholds will be similar to other critical care conditions. (Hb trigger 70 g/L and a Hb concentration target of 70–90 g/L after transfusion) should be used, unless the patient has a history of cardiovascular disease, in which case a trigger of 80 g/L and a target of 100 g/L (Ed – same as in other conditions really, often tricky to tailor in the actively bleeding patient)
10. Coagualtion management is vital (Ed – There are a number of specific recommendations about the management of coagulopathy. These are familiar to us as they are pretty much the same as management for other bleeding emergencies whilst on anticoags).
11. All hospitals should have a GI bleeding lead and agreed pathways for the management of acute LGIB (Ed – presumably this one). Hospitals that routinely admit patients with LGIB should have access to 7/7 on-site colonoscopy and the facilities to provide endoscopic therapy (Ed not stated as 24/7 and they probably don’t mean that)
12. All hospitals that routinely admit patients with LGIB should have access to 24/7 interventional radiology either on site, or via a formalised referral pathway to another hospital (Ed – I’d agree but this is really quite uncommon in the UK unless we centralise these admissions).

Discussion

These seem to be helpful and useful practical and pragmatic recommendations for the management of LGIB. It is interesting to see how the authors balance the strength of their opinions with the strength of the evidence. In many cases there is little correlation between opinion and evidence, although in their defence the authors are quite open about this. It does mean that we must understand that the overall level of underlying evidence from high ranking trials is relatively low, but this may be the best evidence available at this time. An example is the recommendation for angiography in the haemodynamically unstable patient, this is described as Strong recommendation, low quality evidence which is almost the opposite of what we expect in evidence based medicine. Several of the other recommendations contain this apparent cognitive dissonance.

The potential to identify a group of low risk patients suitable for out patient management is attractive under the current pressures we face. However, the risk stratification tool has a 5% failure rate, has not been validated outside the UK, and in a relatively small data set. I think it could be used, but with a good overall clinical review to identify patients in whom other concerns would make discharge unsafe.

From my perspective the adoption of the strategies in this paper is problematic. The strength of the evidence underlying many aspects are moderate/weak and are thus heavily influenced by expert opinion. I would like to see EM input into any guidelines that might influence our management as the evidence base for the safe to discharge cohort is arguably limited. For admitted patients the paper has some great suggestions which are rather reliant on the availability of in patient and out patient services to back up the initial assessment and risk stratification. In a large centre such as Virchester many of these will be possible to achieve and have the potential to improve the patient experience. However, in smaller hospitals with less robust access to endoscopy, angiography and interventional radiology these suggestions will be challenges and perhaps a network approach will be required

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