emDocs - November 14, 2016 - Authors: Long D and Long B - Edited by: Koyfman A
"Summary
A thunderclap headache (TCH) is a headache that reaches 7 (out of 10) or more in intensity within less than one minute. Every patient presenting with TCH must be assumed to have a life-threatening intracranial condition. As many conditions can present with TCH (most commonly SAH or RCVS), a thorough history is essential in evaluating for risk factors for other conditions. The Emergency Physician must keep in mind that the absence of associated symptoms and a normal physical and neurological exam does not exclude a serious cause in a patient with a TCH; the patient still requires a diagnostic workup. Due to the high morbidity and mortality of subarachnoid hemorrhage, any patient that presents with TCH must be evaluated for SAH. A noncontrast head CT has a sensitivity for SAH nearing 100% if performed within 6 hours of headache onset. We recommend TCH patients to receive a CTA with the initial head CT, as this will further evaluate for an aneurysm, cervical artery dissection, stroke, or RCVS. Decisions on further imaging and diagnostic evaluation should be made in conjunction with neurology and possibly neurosurgery."
