February was the last of my three months at Family Medicine clinical rotation. In addition to normal clinical consultations, we also had to take turns attending spontaneous demands coming “from the street”, in a primary care resource center that works similar to a green zone setting in the ED. During these three months, I’ve noticed that, sometimes, the easiest patient to manage is that one with a major complaint like chest pain, severe dyspnea, altered mental status, and so on. Things become more difficult, however, when you have a patient that has just a headache, a very common symptom, but one that could be related to an enormous variety of conditions, some of which life-threatening. Sometimes, you dig under the “green” patient and discover a secret “yellow” or even a “red” condition.
Next, I will try to put some light on the investigation of one of the most common complaints I’ve seen, and one of the symptoms that always put a bug in the ear: Headache.
Headache is a very common complaint at the Emergency Department, being the fifth leading cause of ED visits¹. Alarmingly, about 0.5% of patients who had presented with a headache and discharged home have returned with a serious condition, of which 18% were acute ischemic stroke.²
Patients can describe headache, a very nonspecific and hard to clarify complaint, in diverse ways, ranging from saying solely “my head hurts” to making a circular gesture around his/her head with. Therefore, identifying potential risk factors that can alert us to potential adverse outcomes. Here are a few decision rules for patients with headache:
The mnemonic SNNOOP10³ refers to the red flag symptom and findings to screen, which may point to related secondary headaches.
Ottawa Subarachnoid Hemorrhage Rule
Ottawa Subarachnoid Hemorrhage Rule fundamentally helps to rule out (Sensitivity: 100% Specificity: 15%) subarachnoid hemorrhage (SAH) in patients with headache. You can apply this rule ONLY IF:
- The patient is alert and older than 15 years old with
- New severe non-traumatic headache, reaching maximum intensity within 1 hour and
- NO new neurological deficits, no history of intracranial tumors, previous SAH or aneurysms, and similar headaches (≥ 3 episodes over ≥ 6 months)
Risk factors are:
- Age ≥ 40
- Neck pain or stiffness
- Witnessed loss of consciousness
- Onset during exertion
- “Thunderclap headache” (defined as instantly and immediately peaked pain)
- Limited neck flexion on examination (defined as the inability to touch chin to chest or raise head 3 cm off the bed if supine)
If ANY of these factors is present, SAH can not be ruled out, and this patient needs further investigation. A recent study has assessed the performance of the Ottawa decision rule for patients presenting with headache in the ED, showing that it is a highly sensitive test (100%), making it useful in order to “not miss the disguised red patient.”5 Not by coincidence, Tintinalli’s book states with bold letters: “Acute onset of a severe headache is subarachnoid hemorrhage until proven otherwise.”
Neuroimaging is a valuable diagnostic tool but is also an expensive one. Besides, it can be harmful due to radiation exposure or contrast use.
There is a lot of controversy in the literature regarding the question “When to image patients with a headache?”, but the consensus is to image when a patient presents with red flags, especially those related to vascular causes, raised intracranial pressure and focal signs.4
CT scan is the preferred method to investigate SAH, with excellent sensitivity and specificity (both bigger than 90%) in the first 6 hours of hemorrhage.6 However, if more time has passed, other diagnostic tools will probably be required in this case. Also, as said before, the costs are a major factor regarding neuroimaging, and sometimes you have to use what you have.
- Suspected infectious disease of the CNS
- Suspected SAH
- Suspected idiopathic intracranial hypertension – as diagnostic and treatment
- Coagulopathy (including anticoagulant drugs) or thrombocytopenia
- Infection at the puncture site
- Suspected epidural abscess
- Findings on the CT scan to deferring LP
- Brainstem herniation
- Mass with signs of compression of the 4th ventricle
- Signs of increased intracranial pressure or midline shift
- Acute intracranial hematoma
Disposition and Follow-up(7,8)
- Most patients can be discharged with a simple painkiller prescription. About 95% of patients presenting to the ED with headache have a benign etiology and don’t need further investigation in the ED.
- The acute benign headache usually resolves with acetaminophen, NSAIDs, hydration, and rest.
- An adequate follow-up plan is a good practice since most headaches are due to chronic conditions that may benefit from pharmacologic prophylaxis as well as lifestyle modifications.
This subject is open to discussion. Although it looks (and it is) a simple and easy-to-manage condition 90% of times, it has the potential to give the doctor some headache, too!
References and Further Reading
- American College of Emergency Physicians Clinical Policies Subcommittee (Writing Committee) on Acute Headache:, Godwin, S. A., Cherkas, D. S., Panagos, P. D., Shih, R. D., Byyny, R., & Wolf, S. J. (2019). Clinical Policy: Critical Issues in the Evaluation and Management of Adult Patients Presenting to the Emergency Department With Acute Headache. Annals of emergency medicine, 74(4), e41–e74. https://doi.org/10.1016/j.annemergmed.2019.07.009
- Dubosh, N. M., Edlow, J. A., Goto, T., Camargo, C. A., Jr, & Hasegawa, K. (2019). Missed Serious Neurologic Conditions in Emergency Department Patients Discharged With Nonspecific Diagnoses of Headache or Back Pain. Annals of emergency medicine, 74(4), 549–561. https://doi.org/10.1016/j.annemergmed.2019.01.020
- Do, T. P., Remmers, A., Schytz, H. W., Schankin, C., Nelson, S. E., Obermann, M., Hansen, J. M., Sinclair, A. J., Gantenbein, A. R., & Schoonman, G. G. (2019). Red and orange flags for secondary headaches in clinical practice: SNNOOP10 list. Neurology, 92(3), 134–144. https://doi.org/10.1212/WNL.0000000000006697
- Good C. (2019). British Society Of Neuroradiologists Guidelines for Headache. Retrieved July 23, 2020, from https://bsnr.org.uk/_userfiles/pages/files/standards_and_guidelines/bsnr_guidelines_for_imaging_in_headache_april_2019_final.pdf
- Wu, W. T., Pan, H. Y., Wu, K. H., Huang, Y. S., Wu, C. H., & Cheng, F. J. (2020). The Ottawa subarachnoid hemorrhage clinical decision rule for classifying emergency department headache patients. The American journal of emergency medicine, 38(2), 198–202. https://doi.org/10.1016/j.ajem.2019.02.003
- Kwiatkowski T. and Friedman B. W. (2018). Headache Disorders. In: R. M. Walls, R. S. Hockberger, M. Gausche-Hill, K. Bakes, J. M. Baren, T. B. Erickson, A. S. Jagoda, A. H. Kaji, M. VanRooyen, R. D. Zane, (Eds.) Rosen’s Emergency Medicine Concepts and Clinical Practice (9th ed. pp: 1265-1277). Philadelphia, PA: Elsevier.
- Perry, J. J., Stiell, I. G., Sivilotti, M. L., Bullard, M. J., Emond, M., Symington, C., Sutherland, J., Worster, A., Hohl, C., Lee, J. S., Eisenhauer, M. A., Mortensen, M., Mackey, D., Pauls, M., Lesiuk, H., & Wells, G. A. (2011). Sensitivity of computed tomography performed within six hours of onset of headache for diagnosis of subarachnoid haemorrhage: prospective cohort study. British Medical Journal (Clinical research ed.), 343, d4277. https://doi.org/10.1136/bmj.d4277