brain part 2 Flashcards
within how many hours can IV recombinant tPA be given after a patient exhibits sx of an acute ischemic CVA
within 4.5 hours of sx onset
risk factors for CVA include (6)
HTN (most important)
smoking
DM
HLD
ETOH excessive
elevated homocysteine level
usual first therapy for patients who suffered an ischemic (not hemorrhagic) CVA
PO așa
eligible CVA patients with large vessel occlusion should receive embolectomy within how many hours of sx onset
6
target BP for ischemic CVA patient
under 185/110
fluid, temp, BG anesthetic considerations for CVA patient
fluid supports CO, BP, CPP, and improves BF by decreasing blood viscosity
monitor BG’s, tx high BG with insulin. glucose is converted to lactic acid in severe ischemia and is associated with bad outcomes
-controlled hypothermia can reduce CMRO2
management considerations for cerebral vasospasm following SAH include
reducing HCT to 30
niMOdipine
daily trans cranial doppler exams
triple H therapy (HTN, hemodilution, hypervolemia)
most common cause of subarachnoid bleeding
aneurysm rupture in circle of willis
what increases risk of aneurysm rupture
HTN(?) or an acute reduction in ICP. basically ICP creates a tamponade effect.
surgical options for hemorrhagic CVA
aneurysm clipping or endovascular coiling
-to minimize risk of re bleeding, surgical repair should take place within 24-48h following initial bleed
if you heparinize for the endovascular coil to be placed and the aneurysm ruptures during this time, you should
reverse the heparin, lower map to low/normal range, can give adenosine to help surgeon stop bleeding
intraop BP control for hemorrhagic CVA
also considerations for open repair where surgeon is clamping
SBP should be between 120-150mmHg
-if patient undergoes an open repair, clamp is placed on proximal feeder vessel. this reduces transmural pressure and decreases the risk of aneurysm rupture so you won’t need controlled HoTN but you will need a normal/high BP to perfuse collateral circulation.
too high and no clamp- rupture could occur
too low- auto regulation is impaired and could not be perfusing
when cerebral vasospasms most commonly occur
how to monitor for them
presentation
dx
tx
most commonly occur 4-9 days following SAH
frequent neuro checks and daily transcranial doppler exams
most common presentation is new neurologic deficit or altered LOC
dx: cerebral angiography is gold standard
tx: aimed at maintaining CPP (increase MAP 20-30mmHg above baseline), if vasospasm occurs, triple H therapy (hypervolemia, HTN, hemodilution to 27-32%), nimodipine, balloon angioplasty
a medically refractory vasospasm can be treated with what before balloon angioplasty?
intra arterial vasodilators, CCB’s like verapamil or nicardipine. can also try papaverine and milrinone
define cerebral salt wasting syndrome
patients who suffer SAH are at risk for this
most common cause of hyponatremia in this population. brain releases natriuretic peptide which causes contraction, hyponatremia, and sodium washing by the kidney.
CSW is tx with isotonic crystalloids
distinction between CSW and SIADH
CSW is tx with isotonic crystalloids while SIADH is tx with fluid restriction since its associated with slight hypervolemia
if you have a minor head injury and satisfy these requirements, you do not need a CT
no physical evidence of trauma above the clavicles
no HA
no n/v
no neurologic deficit
no impairment of short term memory
no intoxication
no seizures
age <60y
review GCS and which number is associated with TBI
<8, TBI
ways to reverse wafarin (3)
FFP, prothrombin complex concentrate, recombinant factor 7a
ways to reverse clopidogrel and/or ASA
platelet transfusion,
anesthetic management of TBI, keep CPP
> 70mmHg
two things to specifically avoid in a patent with TBI
prolonged hyperventilation can worsen cerebral ischemia in patents with TBI
steroids can worsen neurologic outcomes
albumin and TBI
linked to poor outcomes
nitrous oxide and TBI
PTX can be lurking, you dont know. just dont touch it with TBI victim
jacksonian march
a partial seizure that progresses to a generalized seizure
tonic phase versus clonic phase
tonic: whole body rigidity. TONE
clonic: repetitive jerking motions
grand mal seizure key points/distinctions
acute tx
surgical tx
generalized tonic/clonic activity
respiratory arrest due to hypoxia an increased O2 consumption due to increased brain activity
acute tx: propofol, diltiazem, thiopental
surgical tx: vagal nerve stimulator or resection of foci
focal cortical sz sx
localized to particular cortical region
can be motor or sensory
usually no LOC