Reading the SIGN head injury guideline has prompted GP Dr Chris Barclay to improve his history taking and case analysis
Significant head injury, although common in the community, is not seen with any great frequency in general practice. It is, however, an important cause of continuing and sometimes avoidable morbidity.
Serious head injury where skull fracture or unconsciousness is present obviously requires urgent hospitalisation. But doctors in general practice are more likely to be consulted by someone who had a road traffic accident yesterday, or who feels off colour after a knock on the head.
Decisions require fine judgment and this is where the new SIGN guideline is helpful.1 First, it contains the information used to calculate a patient's Glasgow Coma Score (see Figure 1, below). Anything less than a 15/15 score requires referral to hospital.
|Figure 1: The Glasgow Coma Scale and Score (reproduced from the SIGN guideline
' Early management of Patients with a Head Injury', 2000)1
Other factors that should prompt referral include amnesia for the incident or subsequent events, neurological symptoms (e.g. severe headache, nausea and vomiting), and the possibility of a skull fracture.
Similarly, if the home circumstances are not adequate or there are doubts about the diagnosis, hospital referral is advised.
The guidelines also mention the presence of medical co-morbidity, in particular alcohol abuse and anticoagulant use. This is particularly pertinent with the escalating use of warfarin in the elderly and frail. It is poignant too with the recent tragicoand premature death of Scotland's First Minister, Donald Dewar, whose demise followed a fairly trivial knock on the head while on warfarin therapy.
Special mention is made of high impact head injury, and the most common situation here must be a road traffic accident. The guideline advises referral in this situation and in head injuries following falls from a height.
The possibility of there being an operable intracranial haematoma has been calculated for a range of situations:
- If the patient has had a head injury, but has not been rendered unconscious and has no other features of concern, the chance is 1:31300
- If post-traumatic anmesia is present this figure rises to 1:6700
- If a fracture is present too, it shoots up to 1:29
- If the Glasgow Coma Score is even slightly less than 15/15 the risks rise steeply.
Reading these figures challenges me to become more focused in my history taking and case analysis, although I have a slight problem in deciding where a bump on the head stops and a head injury starts.
The guidelines make particular reference to two special circumstances:
- Children: The index of suspicion should be much higher in children than in adults, especially children under 4 years of age, and we should not forget the possibility of non-accidental injury.
- GPs working in remote areas: The guidelines are quite explicit – remoteness of location or the need for transfer by air must not alter management. The only exception is in the case of minor head injury where admission to a local community hospital is possible.
The new guideline has been meticulously worked up: no short cuts have been taken. I found reading through the guideline to be a worthwhile exercise. Much of it relates to clinical situations that I am never likely to be confronted with, but the cross-fertilisation effect of reading off piste is remarkable.
- Early Management of Patients with a Head Injury. A national clinical guideline. Scottish Intercollegiate Guidelines Network. SIGN Publication Number 46. August 2000.