From the Guidelines
Given the severe headache with nausea and vomiting, but no altered consciousness and a normal non-contrast CT scan, the next step is to consider a lumbar puncture (LP) to rule out subarachnoid hemorrhage (SAH) or other conditions that may not be visible on a non-contrast CT, as recommended by guidelines for the management of aneurysmal subarachnoid hemorrhage 1.
Key Considerations
- Administer anti-emetics such as metoclopramide 10mg IV or ondansetron 4-8mg IV to control nausea and vomiting.
- Consider administering acetaminophen 1000mg PO or IV for headache management, but avoid NSAIDs until SAH is ruled out due to potential bleeding risks, as suggested by guidelines for hyperacute stroke care 1.
- Monitor the patient's vital signs, neurological status, and pain level closely.
- If the patient's condition worsens or if the LP results indicate an abnormality, consider consulting a neurologist or transferring the patient to a higher level of care, as recommended by guidelines for the management of aneurysmal subarachnoid hemorrhage 1.
Rationale
The clinical presentation of a severe headache with nausea and vomiting, but no altered consciousness, is consistent with a possible SAH, which requires prompt diagnosis and treatment to prevent rebleeding and improve outcomes, as highlighted by the Canadian Stroke Best Practice Recommendations 1 and the ACR Appropriateness Criteria for cerebrovascular diseases 1. A normal non-contrast CT scan does not rule out SAH, and a lumbar puncture is necessary to confirm the diagnosis, as recommended by guidelines for the management of aneurysmal subarachnoid hemorrhage 1.
From the Research
Next Steps for Patient with Severe Headache
The patient presents with a severe headache (10/10), nausea, vomiting, and a normal computed tomography (CT) scan without contrast, but no altered mental status. The following steps can be considered:
- A lumbar puncture (LP) and cerebrospinal fluid (CSF) analysis may be necessary to exclude subarachnoid haemorrhage (SAH), as a noncontrast CT brain scan is not sensitive enough to exclude SAH 2, 3.
- The decision to follow a negative CT with an LP in all cases needs careful consideration, as CSF results may only rarely confer therapeutic benefit to patients suspected of SAH 2.
- If SAH is excluded, further investigations, such as MRI brain and vascular imaging with MRI or CT angiography, should be considered to exclude other aetiologies 3.
- The patient's symptoms, such as nausea and vomiting, may be associated with SAH, and a high index of suspicion should be maintained for SAH, even in the absence of headache 4.
Considerations for Lumbar Puncture
- A lumbar puncture may be performed at least 12 hours after the onset of the headache to exclude SAH 3.
- The diagnostic yield of LP to diagnose or exclude SAH after negative head CT is very low, due to low prevalence of the disease and uninterpretable or inconclusive samples 5.
- A clinical decision rule may improve diagnostic yield by selecting patients requiring further evaluation with LP following nondiagnostic or normal noncontrast CT brain imaging 5.
Timing of Computed Tomography Scan
- A CT scan taken within 6 hours of onset of sudden headache may be sufficient for confirming or ruling out subarachnoid bleeding in patients with sudden headache who have no neurologic deficits 6.