Nursing care
Subarachnoid Hemorrhage nursing care: what to assess and what to do first
Written and reviewed by Dana Whitfield, RN, MSN · 5 min read · Updated September 2026
Short answer
Subarachnoid hemorrhage nursing care starts with recognising the thunderclap headache: sudden, at maximum intensity within seconds, and described as the worst headache of the patient's life. Priority actions are neuro checks, blood pressure control, seizure precautions, and a dark, low-stimulation environment while the team works toward securing the aneurysm.
The clinical picture
The history carries the diagnosis before any scan does. A patient who says the headache hit like a blow to the back of the head, reached full intensity within seconds, and is unlike anything they have felt before is describing a thunderclap headache, and that description alone should move subarachnoid hemorrhage to the top of the differential. It is not a headache that builds over an hour. It arrives essentially instantly, often during exertion, straining, or sex, and patients frequently remember the exact moment it started.
Alongside the headache, expect nuchal rigidity, photophobia, nausea and vomiting, and a variable level of consciousness ranging from alert to comatose depending on the grade of the bleed. Some patients report a sentinel headache days to weeks earlier, a smaller warning bleed that was dismissed or self-treated. A brief loss of consciousness at onset, or a witnessed collapse, raises suspicion further. Third cranial nerve palsy, with a dilated, sluggish pupil and ptosis on one side, points to a posterior communicating artery aneurysm compressing the nerve.
Assessment: what to look for and in what order
Start with the history question: sudden or gradual onset. That single question does more diagnostic work here than most of the physical exam. Then move to level of consciousness using the Glasgow Coma Scale, because a falling GCS is the earliest sign of rebleeding or rising intracranial pressure, both of which are more dangerous than the initial bleed itself in the first 24 hours.
Check pupils for size, equality, and reactivity, looking specifically for a unilateral blown pupil. Assess for nuchal rigidity and photophobia, both markers of meningeal irritation from blood in the subarachnoid space. Take vital signs with attention to blood pressure trends and to the Cushing triad of widening pulse pressure, bradycardia, and irregular respirations, which signals impending herniation. Grade the bleed using the Hunt and Hess or WFNS scale if your unit uses one, since this drives the intensity of monitoring that follows.
Immediate interventions
Keep the patient on strict bed rest with the head of bed elevated 30 degrees, in a quiet, dimly lit room. Stimulation, including bright light, noise, and unnecessary handling, can trigger rebleeding or increase intracranial pressure, so cluster care and limit visitors and procedures where possible.
Control blood pressure to the parameters ordered, typically keeping systolic pressure below a defined ceiling until the aneurysm is secured, since uncontrolled hypertension raises rebleed risk while hypotension risks cerebral ischemia. Start seizure precautions and anticipate an order for nimodipine, given specifically to reduce cerebral vasospasm rather than to lower blood pressure generally. Avoid Valsalva: stool softeners are standard, and the patient should be coached not to strain, cough forcefully, or bear down. Prepare the patient and family for likely angiography and either coiling or clipping to secure the aneurysm.
Ongoing nursing management
Vasospasm is the complication to watch for from around day 4 through day 14, presenting as a new focal deficit, confusion, or a drop in GCS in a patient who had been stable. Frequent neuro checks through this window are not routine box-ticking; they are how vasospasm gets caught before it becomes an infarct. Report any new weakness, speech change, or personality shift immediately rather than waiting for the next scheduled assessment.
Monitor for hyponatremia from cerebral salt wasting or SIADH, both common after subarachnoid hemorrhage and both capable of worsening cerebral edema if missed. Maintain euvolemia as ordered, track strict intake and output, and watch for signs of hydrocephalus, including worsening headache, vomiting, and decreasing consciousness, which may need a ventriculostomy. Keep the environment low-stimulation throughout the acute phase, not just on admission, and continue DVT prophylaxis appropriate to the patient's bleeding risk.
Patient and family education
Explain in plain terms why the room is kept dark and quiet and why visitors are limited: it protects against a second bleed while the aneurysm is not yet secured. Families often want to bring in phones, television, or a stream of visitors to help the patient, and understanding the rationale makes them allies in maintaining that environment rather than working against it.
Teach the family to recognise and report a new headache, confusion, or weakness promptly, since these can signal vasospasm or rebleeding rather than simply 'a bad day.' Cover the avoidance of straining, heavy lifting, and Valsalva-type activity, and give a realistic picture of recovery: some patients return to baseline, others live with cognitive or physical deficits, and follow-up neurology and rehabilitation input will shape what recovery actually looks like for this patient.
How this appears on the NCLEX
Expect a stem built around the classic history: sudden, severe, worst-of-life headache, sometimes with a brief loss of consciousness or vomiting. The correct next action is almost always about safety and monitoring, not medication first, so questions frequently test whether you pick 'notify the provider and initiate neuro checks' over an intervention that treats pain alone.
Distractor answers often offer to treat the headache with analgesia as the priority, or suggest raising the head of bed flat, or encourage ambulation. The tested principle is recognising a neurological emergency from history alone and prioritising rebleed prevention, low stimulation, and blood pressure control. Questions on vasospasm timing (days 4 to 14) and on nimodipine's actual purpose, cerebral protection rather than general antihypertensive use, are also common.
The next step on this is the same as on everything else here: answer questions and read the rationales. Our neurological practice questions are the closest set to what this page covers.
Common questions
What is the classic symptom of subarachnoid hemorrhage?
A sudden, severe headache that reaches maximum intensity within seconds, often described by the patient as the worst headache of their life. It is the thunderclap pattern, not the gradual build of a tension or migraine headache, that raises suspicion.
Why is nimodipine given after subarachnoid hemorrhage?
Nimodipine is given to reduce the risk and severity of cerebral vasospasm, not primarily to lower systemic blood pressure. It is a calcium channel blocker with selective action on cerebral vessels and is a standard part of vasospasm prevention protocols.
When does vasospasm typically occur after a subarachnoid bleed?
Vasospasm risk peaks roughly between day 4 and day 14 after the bleed. Any new focal deficit, confusion, or drop in level of consciousness during this window should be treated as a possible vasospasm until ruled out.
Why is the room kept dark and quiet for these patients?
Stimulation from light, noise, or unnecessary handling can raise intracranial pressure or trigger rebleeding before the aneurysm is secured. A calm, low-stimulation environment reduces that risk during the acute phase.
What blood sodium problem is common after subarachnoid hemorrhage?
Hyponatremia from cerebral salt wasting or SIADH is common and needs close monitoring, since either can worsen cerebral edema if left untreated. Strict intake and output tracking helps catch it early.