SUBARACHNOID HEMORRHAGE

Question 1

MANAGEMENT

Answer 1

1. IMAGING
   CT Head: Within 6 hrs of headache
   Sensitivity declines with time

100% Sensitivity and 100% Negative Predictive Value if done within 6 hours

2. LUMBAR PUNCTURE:
   LP performed within 12 hours of onset may have false negative results because blood has not diffused down

LP Contraindications
Infection at the site of the LP
Coagulation abnormalities
Risk of brain herniation

CSF opening pressure (if done in left lateral decubitus)

Tube 1 - cell count, gram stain, xanthocromia

Tube 2 - protein, glucose

Tube 3 - culture & sensitivity, viral studies

Tube 4 - cell count

Low grade evidence for CTA as an alternative to LP where clinical concern for a aneurysmal SAH persists despite a negative non-contrast CT Head

3. EARLY NEUROSURGICAL CONSULTATION
4. PAIN CONTROL

5, BLOOD PRESSURE MANAGEMENT: Lower SBP < 160
Avoid lowering below SBP 120

Labetolol
Dosing: 10-20 mg IV over 2 min repeat 10 mg q 10 min PRN to total of 300 mg
OR
1-2 mg / min

C/I:
Pheochromocytoma, CHF, Asthma, Heart Block

Hydralazine:
Dosing: 5 mg IV, repeat 5-10 mg q 20 min
Goal DBP<110

Nicardipine
5 mg / hr IV infusion and titrate by 2.5-5 mg / hr (max 15 mg / hr)

6. REVERAL OF COAGULOPATHY

Warfarin with elevated INR:
Octaplex (PCC) 80mL (2000 U)

time intravenous infusion
If bleeding persists after giving a weight-based or fixed dose or if the INR does not meet the goal (eg, INR <1.6) within 30 minutes of the infusion, an additional 500 units as a one-time intravenous infusion may be considered.

10 mg Vit K IV, hold Warfarin

repeat INR.

Goal INR < 1.4

Plt goal > 100 k

DDVAP if uremic

Rivaroxaban / Apixaban / Edoxaban: Octaplex (PCC) 80mL (2000 U)
+/- 10 mg Vit K IV if elevated INR

Heparin:
Protamine Sulfate (time dependent dosing)
Heparin: 1 mg protamine/100 units heparin
Maximum dose is 50 mg.
Protamine dose requirement decreases as heparin is metabolized.
Low-molecular-weight heparins:
Last dose given within 8 hours: 1 mg protamine/1 mg of low-molecular-weight heparins
Second dose of 0.5 mg protamine/1 mg of low-molecular-weight heparins if bleeding continues
If last dose given between 8-12 hours prior: 0.5 mg protamine/1 mg of low-molecular-weight heparins
If >12 hours, a dose of protamine may not be required

Dabigatran:
idarucizumab 5 g IV
fXa: andexamet, TXA

Thrombocytopenia: platelet transfusion

7. PREVENTION OF VASOSPASM
   Nimodipine 60 mg PO q 4 h x 21 days
8. SEIZURE PPX
   Keppra: 20 mg / kg IV loading dose at a rate of 5-15 min), max 2000 mg IV load

THEN

1000 mg PO bid for 7 days

9. ICP MANAGEMENT
   Elevate head of bed to 30 degrees
   Mannitol 0.5-1 g/kg intravenous
   20 g / 100 ml
   3% hypertonic saline 100 mL intravenous
   Intubate, sedate, +/- paralyze
   Drain excessive CSF with intraventriculoperitoneal shunt
10. NEUROVITALS
    Monitor q 1-4 hrs

Question 2

DOCUMENTATION

Answer 2

1. CLINICAL FEATURES
   Thunderclap Headache (83%)
   Onset w/ exertion
   Loss of Consciousness
   Neck pain or stiffness (24-35%)
   Nausea / Vomting (77%)

Hypertension

Ask about previous headache

Risk Factors:
PCKD
FHx Aneurysmal SAH
Connective Tissue Disorder (EDS)
HTN
Tobacco
EtOH
Sympathomimetic Drugs

2. OTTAWA SUBARACHOID HEMORRHAG RULE: FEATURES THAT INCREASE THE LIKELIHOOD OF SAH
   Use in an alert, adult with non traumatic headache peaking within an hour

Age >= 40
Neck Pain or Stiffness
Witnessed LOC
Onset with exertion
Pain peaked immediately (within seconds)
Limited neck flexion on exam

3. PHYSICAL EXAM
   Vital Signs
   GCS
   Nuchal Rigidity
   Neurological Exam
   Trauma Survey
4. TIME OF CT READ

Factors that contribute to ruling out SAH with 100% Sensitivity:
Negative CT
Normal Opening Pressure
Negative LP

4. LUMBAR PUNCTURE
   Positive Finding:
   Xanthochromia
   Elevated Opening Pressure

Normal Opening Pressure: 50 - 200 mmH20

5. TIME OF NEUROSURGICAL CONSULTATION

Question 3

KEY POINTS

Answer 3

97% of patients report a sudden, severe headache.

11%-25% thunderclap headache are SAH

Headaches are lateral in in 30% of patients

Ottawa SAH Rule:
Sensitivity 100%
Specificity 7.6-15.3%
Externally validated

NON CONTRAST CT HEAD
98.7% Sensitive if the following elements are met for CT to be an exclusion test at <6 hours from ictus
Patient Characteristics:
Isolated thunderclap headache
No seizures, loss of consciousness, or neck pain
Hematocrit >30%
Accurate time of onset
Normal neurologic exam and no meningismus

Test characteristics:
Indication listed as “rule out aneurysmal subarachnoid hemorrhage or thunderclap headache”
Third-generation CT scanner or newer
Image is technically adequate (no motion artifact)
Thin cuts ≤5mm through base of brain
Hematocrit >30%
Attending level radiologist who routinely reports on head CT images

non-contrast head CT is still the initial test of choice and has a sensitivity of ~85% if > 6 hrs