ICH & SAH Flashcards
intracranial hemorrhage
it’s an umbrella term including: subdural hematoma, epidural hematoma, intracerebral hematoma, subarachnoid hemorrhage
what’s the pacing of a subdural hematoma?
slow
what’s the pace of a epidural hematoma?
pretty quick, several hours lucid, the LOC, then goes quickly. the middle meningeal artery, once blood fills the space down you go,
what’s the leading cause of ICH?
trauma
what are the other causes of non-traumatic ICH
HTN, aneurysm, then AV malformation/other
primary causes of ICH?
HTN, cerebral amyloid angiopathy, drugs, coagulopathy
secondary causes of ICH
vascular malformation (AVM), moyamoya, hemorrhagic conversion-ischemic stroke, venous sinus thrombosis, tumor, cerebral vasculitis
what are pathological changes of HTN hemorrhage
micro aneurysms of the perforators (Charcot Bouchard Aneurysms) accelerated atherosclerosis large vessels
where in the brain do HTN bleeds happen
how do you manage ICH?
-blood pressure control -reversal of anti-coagulation -management of ICP -reducing secondary risks - identify etiology
BP control guidelines
how do you achieve hemostasis w/ warfarin
- vitamin K 10 mg IV x 1 2. Kcentra (weight & INR based) 3. FFP
hemostasis w/ antiplatelets
- platelet transfusion 2. dDAVP (clotting promoter)
hemostasis w/ direct thrombin inhibitors (dabigatran etc)
- activated prothrombin complex concentrate or 2. recombinant factor VII
hemostasis w/ novel oral anti-coagulation
activated prothrombin complex concentrate
what is Cushing’s triad
bradycardia, widening pulse pressure, irregular respirations
what is Monroe Kellie hypothesis
it states that the cranial compartment is incompressible and that the volume inside the cranium is fixed. The cranium and its constituents (blood, CSF, and brain tissue) create a state of volume equilibrium, such that any increase in volume of one of the cranial constituents must be compensated by a decrease in volume of another
what is a cerebral arteriorveous malformation (AVM)
aberrant direct connections between the cerebral arterial and venous systems abnormal connection between arteries and veins bypassing capillary system
common presenting symptoms of AVM
intracerebral hemorrhage seizure headache transient focal neurological deficits progressive focal neurologic deficits
physiology of AVM
at least one fistula between arterial and venous circulation
what does AVM look like?
has peppered appearance
how do you grade an AVM?
using the Spetzler Martin AVM scale risk calculation surgery -size: < 3 cm, 3-6 cm, > 6 cm -eloquent area -venous drainage: superficial or deep
treatment for AVM
-usually 2-6 week reset period -reimage vessels to determine true extent of AVM since sometimes you can’t see AVM b/c of blood in the area , so have to have patient come back for re-imaging. options: -surgical treatment -endovascular treatment - embolization -radio surgery (<3 cm) -endovascular treatment + surgery
data recommendations for AVM management
SBP < 160 or MAP 110 Glucose: 180 normothermia treat clinical or electrographic seizure, but don’t prophylax.
where can you have traumatic ICH?
frontal, temporal, occipital - anywhere with bony contact.
what are ICH complications?
- hematoma enlargement - over a few hours, re-bleeding. -HTN after hemorrhage -meaningful if 30% increase in 3 hours 2. cerebral edema (increased ICP) -likely happen over couple of days from swelling/irritation from blood on brain -inflammation and vasogenic edema -mass effect (edema volume may be larger than ICH) 3. intraventricular hemorrhage -next few days -occurs with caudate or thalamic hemorrhage -volume of IVH modifies outcome, can get hydrocephalus.
what is the CTA spot sign?
-should not be confused with the MCA dot sign in the sylvan fissure -it’s a univocal contrast enhancement within the ICH -this area will keep bleeding - predictive of hematoma expansion -suggests the dynamic, active hemorrhage HTN bleeds
what would you use to check on the status of AVM 2-3 weeks after initial imaging?
diagnostic cerebral angiogram
what’s a confirmatory test you can do for subarachnoid bleed?
LP - if it’s a bleed you’ll see blood produces in the tap
definition of aneurysm
localized widening of an artery, wall is weakened and may rupture. it must involve all 3 vascular layers
what is a pseudo aneurysm dilation?
caused by damage to one or more layers of the artery as a result of arterial trauma
where is the most common SAH?
anterior communicating artery
risk factors for aneurysm development
HTN atherosclerotic disease smoking trauma - primarily cause pseudo aneurysm GENETIC -polycystic kidney -ehlers danklos type IV -pseudoxanthoma elasticum -fibromuscular dysplasia -familiam intracranial aneurysm
when do aneurysms become symptomatic?
local compression subarachnoid hemorrhage unruptured aneurysms rarely cause symptoms unless causing local compression
incidence of SAH
-incidence increases with age, most commonly between 40-60, high mortality
what happens to sensitivity of CT as time passes?
it’ becomes less and less sensitivity, at 2 weeks from onset it is only 30% sensitive
on what does sensitivity of CT in detecting SAH depend?
- generation of scanner 2. who is reading the scan 3. amount of blood
what should you think about if you’re getting the scan later re: SAH
do LP in a timely fashion so you know if there is blood in the area.
what are signs of meningeal irritation?
Krening’s sign. or you can push on their eyes, if have meningitis, it will give them bad meningeal pain. seen in about 75% of patients and can take several hours to develop
what is imaging modality for aneurysm, CT?
CT angiogram -uses contrast dye to highlight intra cranial vessels -less sensitive for small aneurysms less than 3 mm -may be done rapidly but care should be used in patients with unknown renal function
what is imaging modality for aneurysm, MRA?
MR angiogram -does not require contrast -can take a long time to acquire high quality images -degraded by movement -can miss aneurysm < 3 mm -MRA highly sensitive & specific for detection of intracranial aneurysms.
conventional angiography?
the ‘gold standard’ -20% of small aneurysms can be missed
