Critical Care Management of Aneurysmal Subarachnoid Hemorrhage
I. Introduction: A ruptured aneurysm is a neurosurgical emergency. But, most often you will not rush these patients to the operating room. Instead, you can save their lives by: (1) treating hydrocephalus (2) preventing re-rupture (3) avoiding hyponatremia (4) preventing/treating vasospasm (5) avoiding comorbidities (DVT, pneumonia, UTI, seizure).
II. Initial Exam Outline
- Hunt-hess classification
|1||Asymptomatic, or mild H/A , slight nuchal rigidity|
|2||CN Palsy, Moderate to severe H/A, nuchal rigidity|
|3||Mild focal deficit, lethargy, confusion|
|4||Stupor, moderate to severe hemiparesis, decorticate|
|5||Deep coma, decerebrate|
- Fisher CT Grade
|1||No hemorrhage seen on CT|
|2||SAH less than 1mm thick|
|3||SAH greater than 1mm thick|
|4||SAH with IVH or IPH|
- Focused Neurological Exam
III. Initial Management
- Airway- Make sure that the patient is protecting their airway. Patients with a depressed LOC (GCS <~10, HH >2) may require intubation. Just like hydrocephalus do not let a GCS of 8 be your absolute cutoff for intervention. Assess the patient and make a decision. Hypercapnia is not good for ICP or your patient. We are neurosurgeons and don’t believe in permissive anything.
- Breathing- Yes they need to be breathing
- Circulation- You want the patient to have a blood pressure but uncontrolled hypertension in the setting of an unsecured aneurysm puts the patient at risk for a re-hemorrhage. The goal is to keep the SBP less than 160
- Disability- This is a term most neurosurgeons do not use but it was probably mentioned during your ATLS/Trauma time. This is where you perform a GCS, HH, Neuro exam, and Fisher CT Grade. There are two neurosurgical emergencies related to aSAH (1) Hydrocephalus requiring an EVD (2) IPH with significant mass effect requiring emergent evacuation.
IV. Hydrocephalus- 20% of patients with SAH will have ventriculomegaly and may require an EVD if they have a poor neurological exam
- There is a risk of re-rupture with EVD drainage secondary to changing the transmural pressure. Some will drain at a Pop off 10mmHg and others will drain at a pop off of 20 mmHg (it doesn’t matter).
V. IPH with significant mass effect requiring emergent evacuation- this is a relatively rare phenomenon and in my limited experience is usually the result of a large MCA bifurcation aneurysm
VI. Medical management
- SBP control- goal less than 160. Labetalol, hydralazine, nicardipine gtt
- Seizure prophylaxis- Keppra or Dilantin
- Steroids- dexamethasone + PPI/H2 Receptor blocker
- Nimodipine- prevention of vasospasm (may result in hypotension)
- Amicar- prevention of re-rupture (may increase risk of endovascular complications such as stroke)
- Stool softener/bowel regiment
- Pain medications/Anxiolysis- balancing act between over-sedation and patient discomfort
- Statins- prevention of vasospasm
- Limit stimulation- lights off in room, only one visitor, no loud noises
VII. Timing of operation and Clip v coil will be topics of future post
- Post-operative care
- Blood pressure- most will “let it ride” and others will increase the SBP limit to 180
- Vasospasm- the patient’s exam will ultimately define clinically significant vasospasm. Many centers perform daily TCDs (or near serial angiograms) and these provide useful information but 1/3 of patients have clinically silent vasospasm. It is the 1/3 of patients with clinically significant vasospasm that we need to identify early.
- HHH (Triple H) or more commonly hyperdynamic therapy. The classic HHH included hypertension, hypervolemia, and hemodilution. The commonly cited (and experience) side effects of HHH (pulmonary edema, MI, kidney dysfunction, line infections, hemorrhage and cerebral edema) have lead most centers to focus more on hypertension and normo to slight hypervolemia.
- Endovascular therapy for vasospasm- will be discussed in detail in a future post
- Shunting- 25-50% of patients will end up with some type of EVD that will require weaning and there are two different schools of thought on this process (1) Shunt them and get them out of the unit (2) Wean them, risk ventriculitis, and prolong their ICU stay. What is the
- Sample Admission Order Set
i. Neurochecks q1hr
ii. NS @100cc/hr
v. Amicar 5g IV once now, Amicar drip 42cc/hr *
vi. Mannitol 25gm q4 hrs hold for CVP<8 *
vii. Albumin 25gm q4 hrs hold for CVP>12 *
viii. Pantoprazole 40mg daily
ix. Pravastatin 40mg qhs *
x. Dexamethasone 10mg once now*
xi. Dexamethasone 4mg IV q6 hrs *
xii. EVD popoff 10cm H20 *
xiii. CT angiogram with 3D reconstructions to eval for aneurysm – do not resume metformin if pt takes at home.
xv. Keppra*- we only start on keppra if temporal clot or if the patient has a seizure
xvi. * = controversial to highly controversial