Transcript Stroke: Management of Adverse Effects

Stroke:
Management of Adverse Effects
Presented by: F. Covert RN, BSN
Vasodilator Therapy
Review: Blood Pressure
• Blood pressure is the amount of force
(pressure) applied to the artery walls.
• Systolic: The force applied to arterial walls
during ventricular systole.
• Diastolic: The force applied to arterial walls
during ventricular diastole.
Hypertension
• Chronic hypertension aggravates atherosclerosis and
increases vascular resistance (vasoconstriction)
within the brain.
• Positive effects: Increased vascular resistance
protects the brain from the damaging effects of
systemic hypertension.
• Negative effects: Predisposes the brain to cerebral
ischemia by impairing vasodilator responsiveness.
When diastolic BP exceeds 120mmHg, the
ischemic brain is at high risk of hemorrhage.
Acute on Chronic Hypertension
• Acute increases in blood pressure
superimposed on a chronic hypertensive
state.
• Approximately 50% of all patients positive
for an acute ischemic stroke will have a
history of preexisting hypertension.
• On average these individuals will have
higher blood pressures post acute stroke than
those who were previously normotensive.
Blood Pressure Management
• Treatment of hypertension should be done
very cautiously.
• Neurological deterioration has been
associated with precipitous decreases in
blood pressure induced by emergency
antihypertensive treatment.
• When blood pressure drops below the lower limit
of cerebral blood flow auto-regulation it causes
more widespread cerebral hypoperfusion.
Blood Pressure Monitoring
Ischemic Stroke: Post tPA
• Vital Signs:
• Every 15 minutes for 2 hours from start of
tPA then,
• Every 30 minutes for 6 hours then,
• Hourly for the next 16 hours
Temperature is monitored every 4 hours for 24 hours.
Blood Pressure Monitoring
Hemorrhagic Stroke:
Intra-cerebral Bleed
• Vital Signs:
• Hourly for 24 hours then,
• Every 4 hours ongoing
Labetalol (Trandate)
• Potent alpha and beta blocker
• Slows heart rate and decreases
peripheral vascular resistance
• Use cautiously in patients with
constrictive airway diseases
• IVP: Given over 1-2 minutes in
10mg increments, can be
repeated every 10-20 minutes
(max dose 300mg)
• Drip: Give a 10mg bolus,
followed by a drip started at 28mg/min
• Can be administered in
ICU/CCU, ED, PACU, AMB
Surgery, Radiology, Cardiology
Utilized in Ischemic and Hemorrhagic Stroke Standing Orders
Nicardipine (Cardene)
• Calcium channel blocker
• Decreases systemic vascular
resistance and blood
pressure
• Administered as an IV
infusion, started at
5mg/hour and may be
increased by 2.5mg/hour
every 15 minutes (max
15mg/hour)
• Contraindicated for patient’s
with conduction deficits (i.e.
Second/Third degree heart
blocks)
• Can be administered in
ICU/CCU and ED
Utilized in Ischemic and Hemorrhagic Stroke Standing Orders
Nitroprusside (Nipride)
• Potent vasodilator used in
emergent hypertensive
conditions
• Acts directly on venous and
arterial smooth muscle
• Administer as an IV drip
beginning at 0.3mcg/kg/min,
titrate by 0.2mcg/kg/min to
desired MAP (max
10mcg/kg/min)
• Monitor closely for cyanide
toxicity
• Can be administered in
ICU/CCU and ED
Utilized in the Hemorrhagic Stroke Standing Orders, recommended for
consideration in Ischemic Strokes.
Cyanide Toxicity
• Signs and Symptoms: Nausea, vomiting,
diaphoresis, apprehension, headache,
restlessness, muscle twitching, dizziness,
palpitations, retrosternal pain and/or
abdominal pain.
• If this occurs, stop the infusion and
symptoms should resolve within 10 minutes,
if not then effects are from another source.
Enalapril (Vasotec)
• An ACE-inhibitor that prevents
the conversion angiotensin I to II,
preventing vasoconstriction
• Decreases peripheral arterial and
venous resistance
• Administered IVP at 0.6251.25mg every 6 hours as needed
• Contraindicated in patients with
hypersensitivity or allergy to
ACE-inhibitors
• Can be administered in
ICU/CCU, ED, PACU, 2CN,
AMB Surgery, Radiology,
Cardiology
Utilized in the Hemorrhagic Stroke Standing Orders.
Hydralazine (Apresoline)
• Potent vasodilator with
direct vasodilating effects on
the arterioles
• Administered IVP in doses
of 5-20mg every six hours as
needed
• Contraindicated in patient’s
with Rheumatic Heart
disease
• Can be administered in
ICU/CCU, PACU, ED, AMB
Surgery, 2CN, Birthing
Center, Radiology,
Cardiology
Utilized in Hemorrhagic Stroke Standing Orders.
Volume Expansion
Post-Hemorrhagic Stroke
• Patients are at an increased risk for cerebral
vasospasm after spontaneous subarachnoid
hemorrhage
• Medically induced hypertension has proven to
reduce vasospasm post bleed
• Methods:
• Intra-vascular volume expansion: Used to stabilize vessel
walls from spasm/collapse
• Vasopressor support: Vessels are less likely to spasm while
acutely constricted
• Administration of anti-diuretics: Assist in the retention of
fluids to stabilize vessel walls
Cerebral Ischemia
Utilization of intra-vascular volume
expansion and induced hypertension
are effective in reversing ischemic
deficits from vasospasm, provided that
the treatment commences before the
cerebral infarction occurs. If not,
ultimately it can be used to prevent
further ischemic damage to the
cerebrum post infarct.
References
Phillips, S. (2004). Pathophysiology and
management of hypertension in acute
ischemic stroke. Hypertension, 23, 131-136.
Miller, E.L., Murray, L., Richards, L., et al.
(2010). Comprehensive overview of nursing
and interdisciplinary rehabilitation care of the
stroke patient. Stroke, 41, 2402-2448.
I.V. Push Medication Guidelines. Garden City
Hospital department of pharmacy (2010).