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Three Part Question

In [Adults with mild head injury and a GCS of 15] is [vomiting] a [clinical indicator for the use of CT]?

Clinical Scenario

A 27 year old man presents to the emergency department following an alleged assault in which he was punched and kicked to the head. He did not lose consciousness but is complaining of a mild headache. He has vomited twice since the incident. You wonder whether the vomiting is a clinical indicator for a CT scan?

Search Strategy

Medline 1966-06/04 using ovid interface.
[exp craniocerebral trauma or cranicerebral trauma.mp. or mild head injury.mp. or minor head injury.mp. or traumatic brain injury.mp. or brain injury.mp. or head injury.mp. or head trauma.mp. or head injuries,closed.mp.] AND [exp vomiting or vomit$.mp. or emesis.mp. or clinical predictors.mp.] Limit to Human, English and Adult.

Search Outcome

Altogether 141 papers were found of which 13 were considered relevant. An additional paper of relevance was recently published in the Journal of Neurotrauma, but is not currently indexed on Medline. This was a meta-analysis which included 9 of the relevant papers.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Ando, S. et al, 1992 Japan	147 consecutive patients with head injuries within a 5 month period.	Prospective Cohort	Abnormal CT scans in patients who vomit.	26 patients vomited of which 5 had an abnormal CT scan compared to 6 abnormal CT scans in the non-vomiting group. Odds Ratio 2.58	Does not state what GCS scores these patients had. The study is not specific to adults and only included a small number of subjects.
Nee, P. et al, 1999 U.K.	5416 consecutive patients with head injuries over a 1yr period.	Prospective Cohort	Incidence of vomiting with a skull fracture.	28%	No GCS has been identified for this study. Skull fracture is only a proxy outcome for intracranial problems. Incomplete data as the method suggests follow up data has been collected but it is not reported.
			Sensitivity of vomiting as a predictor of a skull fracture.	28%
			Specificity of vomiting as a predictor of a skull fracture.	93.3%
Mack, L. et al, 2003 USA	133 patients > 65 years of age with mild head trauma and GCS 13-15 during a 12 month period.	Retrospective Review	Abnormal CT scans in patients who vomit	11 patients vomited of which 3 had an abnormal CT scan compared to 16 in the non-vomiting group.	Study is not specific to all adult patients
				Odds Ratio=0.976 P=0.193
Ibanez, J. et al, 2004 Spain	1101 patients with mild head injuries and a GCS score of 14-15 during a 2 year period.	Prospective Cohort	Intacranial injuries in patients who vomit	88 patients vomited of which 21.6% had abnormal CT scans compared to 64 abnormal CT scans in the non-vomiting group.	Study is not specific to adults.
				Odds Ratio=4.29
Dunning, J. et al, 2004 U.K.	35 papers containing 83,636 patients with minor head injury and a GCS of 13-15.	Meta-analysis	Abnormal CT scans in patients who vomit	Relative risk of vomiting and having an abnormal CT scan is 2.13	Not all papers included in this meta-analysis are specific to adults. Some of the papers in this meta-analysis excluded patients who did not sustain loss of consciousness.
				P=0.0005

Comment(s)

Some of the papers included in the meta-analysis state that vomiting is not a clinical indicator for a CT scan, but when these papers are reviewed together vomiting becomes an indicator. Only one paper differentiates between a single vomit and multiple vomits and none of these papers exclude alcohol intoxication which may in itself be a reason for vomiting.

Clinical Bottom Line

Vomiting appears to be an indicator for the use of CT however clinical experience of seeing patients with head injuries should be taken into account before requesting a scan.

References

1. Ando, S., Otani, M. & Moritake, K. Clinical Analysis of Post-Traumatic Vomiting Acta Neurochirurgica 1992; 119: 97-100
2. Nee, P.A., Hadfield, J.M., Yates, D.W. & Faragher, E.B. Significance of vomiting after head injury. Journal of Neurology, Neurosurgery and Psychiatry 1999; 66: 470-473
3. Mack, L.R., Chan, S.B., Silva, J.C. & Hogan, M. The use of Computed Tomography in Elderly Patients Sustaining Minor Head Trauma The Journal of Emergency Medicine 2003; 24 (2): 157-162
4. Ibanez, J., Arikan, F., Pedraza, S., Sanchez, E., Poca, M.A., Rodriguez, D. & Rubio, E. Reliability of Clinical Guidelines in the Detection of Patients at Risk Following Mild Head Injury: Results of a Prospective Study Journal of Neurosurgery 2004; 100: 825-834
5. Dunning, J., Stratford-Smith, P., Lecky, F., Batchelor, J., Hogg, K., Browne, J., Sharpin, C. & Mackway Jones, K. A Meta-Analysis of Clinical Correlates that Predict Significant Intracranial Injury in Adults with Minor Head Trauma. Journal of Neurotrauma 2004; 21(7): 877-885