Presentation and buzz words:
Sudden, severe headache
"Thunderclap"
"Worst headache of my life"
Associated with neck stiffness, photophobia, nausea, vomiting, altered mental status, focal neurological deficits
One liner:
When presenting the one liner, note the location of aneurysm if known, the severity scores (we use mFS & HH, see below), the day of bleed, and what that makes today as well as whether the aneurysm is secured/unsecured.
The day of the bleed is super important because it tells us what secondary complication to expect and look out for.
Knowing whether the aneurysm has been diagnosed and whether it has been secured allows us to guide management.
The severity scores helps ballpark how sick the patient is and how high are the risks for complications.
Example: "Today is post-bleed day 4 of Acomm aneurysm rupture on 7/16, Hunt Hess 3 and modified Fisher 4. s/p coiling on 7/17."
Diagnose etiology:
If your patient is admitted to the NSICU for SAH, we need to diagnose the reason. We mostly worry if it's aneurysmal and want to find the culprit. Aneurysmal SAH behaves differently than other types of SAH.
Review their ED imaging:
Non-contrast head CT will likely show blood in the subarachnoid space and sometimes in the ventricles (look for layering at the occipital horns).
The pattern of the SAH gives us clue on where it came from. Ex: Thick on Sylvian fissure - think MCA aneurysm; mostly cortical location in the setting of a fall under the head bump - think traumatic.
Non-Contrast head CT: Note if there is obstructive communicating hydrocephalus, especially if there is intraventricular hemorrhage.
This may warrant CSF diversion to avoid high ICP with placement of an external ventricular drain, aka EVD.
CTA of head will likely show the aneurysm.
If it didn't, and imaging suspicious for aneurysmal bleed, they go to angio for a diagnostic (and possibly therapeutic) angiogram.
Note the SAH patients that get admitted to the NSICU are the "high grade" scores who are at risk for complications. They likely were not the patients who had a SAH presentation and needed to be diagnosed with an LP showing xanthochromia (yellowish discoloration of cerebrospinal fluid due to breakdown of red blood cells).
SAH ICU course:
Initial hours:
Rebleeding can occur within the initial hours to days after the initial SAH.
Seizures can occur as well.
Hydrocephalus is especially high risk if ventricular hemorrhage is also present. EVDs may be placed by neurosurgery, and permanent shunts may be necessary if weaning is unsuccessful.
Systemic effects: Takotsubo's cardiomyopathy is often present, can also see neurogenic pulmonary edema.
First 72 hours:
Early Brain Injury (EBI) occurs within the first 72 hours after SAH and is characterized by brain edema, seizures, microcirculatory disturbances, and disruption of the blood-brain barrier.
Days 3-21:
Vasospasm refers to the narrowing of cerebral blood vessels following SAH, potentially leading to ischemia and neurological deterioration. The peak incidence is typically observed between days 3 and 10 after the initial bleeding.
Delayed Cerebral Ischemia (DCI) typically manifests 4-14 days after SAH and refers to the occurrence of new or worsening neurological deficits without evidence of vasospasm. (still unclear mechanism)
Calculate severity scores:
Calculate Modified Fisher Score (mFS) to evaluate vasospasm risk.
Calculate Hunt and Hess Scale (HH) (or World Federation of Neurosurgical Societies (WFNS) Scale) to evaluate mortality risk.
Higher grades indicates more severe SAH and higher risk for complications.
#SAH Plan Guidance:
Check neurosurgery's note: Was the aneurysm clipped or coiled? Which artery? Any complications?
Review post-op imaging for new bleeds, hydrocephalus, new hypodensities suggesting strokes.
Does your patient have or need an EVD?
Do they have symptoms of hydrocephalus?
If EVD present, note its settings and pressure readings over the past 24 hours.
What is the weaning plan? Typically weaned once vasospasm risk is lower and hydrocephalus resolved.
Is your patient in vasospasm?
What have we done/are we doing about it?
q1h neuro checks. Typically kept during most of the vasospasm window.
Maintain strict euvolemia. Patients going into vasospasm typically start to dump urine and/or develop SIADH/cerebral salt wasting (CSW), so it is super important to keep them euvolemic so hypovolemia doesn't exacerbate vasospasm - sometimes the most important thing we do in NSICU. Report the total body balance (TBB) each day and check multiple times per day that we are not at negative balance.
Maintain normothermia, normoglycemia.
EKG, troponin to look for any stress cardiomyopathy, do we have an echo ordered?
Normal sodium goals (135-145). What was their last sodium? SAH patients often develop SIADH/CSW and we cannot fluid restrict given above, so they might need help with hypertonics. Think about sending UNa and Serum Osm if suspect SIADH/CSW.
Systolic blood pressure should be individualized to your patient depending on if they have a blood pressure dependent exam. Meaning if they are in spasm, they might have focal symptoms at SBP 140, but if you take them to SBP 180, the symptoms improve... in this case we would give fluids or pressors to maintain their needed perfusion.
If aneurysm unsecured, want SBP <140 to avoid re-rupture risk.
There are several ways to non-invasely monitor for vasospasm such as neuro exam, transcranial dropplers (TCDs), continuous EED (cEEG), CTA and CT Perfusion (CTP).
TCDs are done daily in our NSICU to monitor. Noting the trend is the most helpful data.
Measure mean blood velocity in intracranial vessels: >200cm/s correlates with mild spasm, >250cm/s with moderate spasm, >300cm/s with severe spasm.
Lindegaard ratio is a ratio of the intracranial vessels and the extracranial vessels, when the LR is >6, it confirms that it is indeed intracranial vessel spasm and not hyperemia.
Medications:
Review home meds and make sure the necessary ones have been restarted or addressed.
Diuretics are typically on hold given risk for hypovolemia.
BP meds may be on hold to give us control of their blood pressure with drips that are easily titrated and stopped if needed.
Seizure prophylaxis is needed (likely levetiracetam (keppra)) until the aneurysm is secured or sometimes for a short period of time after. Should not be left indefinitely unless patient had a seizure.
Nimodipine, a calcium channel blocker, is commonly prescribed for 21 days. This has been the only therapy which has decreased delayed cerebral ischemia (different from vasospasm), improving outcomes.
It may drop your patients BP: you may try dosing q2h if that's the case to see if they are tolerating.
Sedation and analgesia. Do they have their pain controlled? If on drips, what is the weaning plan?