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General Emergent Management of Patients with Stroke, Including
Blood Pressure Management
Objectives
• Review initial evaluation of the patient with an AIS– history, physical exam, diagnostics,
imaging
• Discuss acute supportive care– stroke vital signs: ABCC’s, hypertension,
glucose, temperature, seizure management
• Understand that emergent management requires simultaneous evaluation and intervention
Goals of Acute Supportive Care
Assure optimal perfusion and oxygenation
• Protect the C-spine• Secure the airway• Support oxygenation and
ventilation• Assure appropriate circulation
The History
• Age - approximately 65 yr• Sudden onset focal neurologic
deficit• Specific vascular territory• Seizure at onset of Sx: 5%• Headache at onset: 10-30%• Fall or trauma at onset
Time of Symptom Onset
• Most difficult portion of the history• Start when patient “was last seen
normal”• Work forward in time (TV guide)• Patients that awake with symptoms -
onset = time of sleep• Confirm with family, friends, care taker• EMS - bring family along in ambulance
Past Medical History
• Medications:– diuretic, antihypertensive, antithrombotic
• Risk Factors:hypertension TIAsmoking previous strokediabetes atrial fibrillation African-American carotid artery disease
Physical Exam
• Vital signs are vital, – but occasionally
inaccurate
• C-Spine tenderness, pain
• BP in both arms, symmetry of pulses
• Signs of trauma, associated injuries
• Neurologic deficit - characteristic vascular distribution
Stroke Scales
• Severity– NIH stroke scale 0-42, 0 = normal
valid, reproducible, assists in patient selection, facilitates communication
• Functional Scales– m-Rankin 0-5, 0 = normal – Barthel index 100, 100 = normal– Glasgow outcome 0-5, 5= normal
• in NINDS t-PA stroke trial, 0 = normal
Stroke Scales
• NIH stroke scale 0-420-5 mild/minor in most patients5-15 moderate15-20 moderately severe> 20 very severeunderestimates volume of infarct in
non-dominant (R) hemispheric strokes
Diagnostic Testing
• Laboratory studies– CBC, differential, platelets– electrolyte profile, glucose (finger
stick)– INR, aPTT– Troponin
• EKG• CXR
Non-contrast CT of the Head• Initial imaging study of choice• Readily available• Very sensitive for blood in the acute
phase– blood - 50-85 Hounsfield Units– bone- 120 (70-200) Hounsfield Units
• Not sensitive for acute ischemic stroke– nearly 100% sensitive by 7 days
• Posterior fossa structures - bone artifact
Non-contrast CT of the Head
• May shows early signs of ischemia in the 1st 3 hours– loss of gray/white matter distinction– hypodensity– mass effect, edema – hyperdense middle cerebral artery sign
• Re-evaluate the time of symptom onset, if early signs of ischemia are present
ECT
2 hours
24 hours
Other Imaging Modalities
• MRI– standard– DWI/PWI
• Xenon CT• Perfusion CT• CT Angiography
Differential Diagnosis
• Deciphered by history, PE, diagnostics
• DDx:TIA vascular disordersseizure infections
(endocarditis)trauma complex migrainemass lesions metabolic
abnormalities
Stroke Vital Signs
AirwayBreathingCirculation
C-spineGlucose
Temperature
Airway ManagementUpper airway patency
• Maintain C-Spine precautions• Asses level of consciousness • Inspect for loose dentures, foreign
bodies• Suction secretions • Assess gag reflex, tongue control
Oxygenation and Ventilation
• Respiratory rate and depth• Signs of fatigue - Paradoxical
respirations• Breath sounds - (CHF, pneumonia,
COPD)• Supplemental O2 with O2 sat > 95%• Support with Basic airway techniques• Ventilatory support as required
Basic airway techniques
• Foreign body removal
• Suction with rigid suction device
• Positioning– jaw thrust– chin lift
• Nasal airway• Bag valve mask
Advanced Airway Management
• Rapid sequence intubation, orotracheal– sedation and paralysis prevent increase in
ICP
• Most common indications– inability to maintain airway– depressed level of consciousness– need for hyperventilation to manage ICP
• Treat the underlying cause of respiratory distress: CHF, MI, etc.
Monitoring of oxygenation
• Pulse oximetry– indicator of oxygenation not
ventilation– falsely high in CO poisoning– falsely low in PVOD, hypotension,
peripheral vasoconstriction• ABG
– pCO2 allows eval of ventilation– obtain from compressible site
• Supernormal oxygenation– not of proven benefit
Circulation
• Goal: maintain cerebral perfusion• Optimize cardiovascular status• Monitor and reevaluate
Circulation
• Evaluate cardiac history and status
• Cardiac output– preload– afterload– contractility– stroke volume
Circulation
• Monitor vital signs Q 15 min in acute phase– pulse (palpate in all 4 extremities)– heart rate– rhythm – blood pressure (both arms)– central venous pressure
ECG
• Cardiac Arrhythmia: 5% -30%
• Acute MI: 1%-2%• ECG abnormalities
– more common with hemorrhagic infarct
– T-Wave inversions– nonspecific ST and T-wave
changes
Vascular Access
• Two peripheral IVs• Use .9NS or .45 NS
unless hypotensive• Use .9NS if hypotensive• Replace blood products
as indicated
Autoregulation
• The ability of the vasculature in the brain to maintain a constant blood flow across a wide range of blood pressures
• Autoregulation - impaired or lost in the area of the infarction
• Ischemic tissues are perfusion dependant
• Autoregulation is shifted to higher pressure patients with a history of HTN
0
20
40
60
80
100
0 50 100
150
200
250
MAP mm Hg
CB
F
ml/
100m
g/m
in Ischemic
Normotensive
Hypertensive
Autoregulationof Cerebral Blood Flow
Hypertension Ischemic Stroke
• Loss of autoregulation• Treat judiciously if at all• Treatment guidelines - not
receiving rt-PA– AHA: MAP > 130 or Sys BP > 220
• MAP= [(2x DP)+SP]3
– NSA: 220/115
Hypertension - Ischemic Stroke
• Drugs - short acting, titrate • Labetalol
IV: 10-20 mg increments, double dose Q 20 min, max cumulative dose 300mg
• EnalaprilOral: 2.5 - 5.0 mg/day, max 40mg/dayIV : 0.625-1.25 mg IV Q 6hrs, max 5.0
Q 6 hrs
Hypertension -Ischemic Stroke
• NitroglycerinePaste: 1-2 inches to skinIV Drip: 5mcg/min, increase in
increments of 5-10mcg every 3-5 min • Nitroprusside
IV Drip: 0.3 - 10 mcg/min/kgContinuos BP monitoringcheck thiocyanate levels
• AVOID NIFEDIPINE
Hypertension Intracerebral Hemorrhage
• Treat aggressively• Elevate head of bed• Use labetalol, nitroglycerine,
nitroprusside or lasix• AVOID NIFEDIPINE• Keep systolic < 160 mm Hg diastolic < 100 mm Hg
Hypotension
• More detrimental than hypertension• Seek cause and treat aggressively• CVP monitoring may be necessary• Use .9 NS first to ensure adequate
preload• Then add vasopressors if needed
Hypertension: rt-PA Candidate
• Exclude for persistent BP > 185/110
• Check BP q 15 min• May not aggressively lower BP to
meet entry criteria• Use Labetolol or Nitropaste• Avoid Nifedipine
Glucose
• Worse outcome after stroke:– diabetics– acute hyperglycemia at time of infarct
• Mechanism uncertain– increase in lactate in area of ischemia– gene induction, – increased number of spreading
depolarizations
• Insulin is a neuroprotective
Glucose
• Avoid any IV fluids with D5– instruct prehospital personnel not to
give D50 as part of the “coma cocktail” to acute stroke patients
• Check a finger stick ASAP – treat only if low (< 50)
• Use insulin to establish euglycemia
Temperature
• Fever worsens outcome:– for every 1°C rise in temp, risk of poor
outcome doubles (Reith, Lancet 1996)
• Greatest effect in the first 24 hours• Brain temp is generally higher than core• Treat aggressively with acetaminophen,
ibuprofen, or both• Search for underlying cause• Hypothermia currently under
investigation
Seizures
• Occur in 5% of acute strokes• Usually generalized tonic-clonic• Possible causes:
severe strokescortical involvement unstable tissue at riskspreading depolarizationshx of seizure disorder
Seizures• Protect patient from injury during ictus• Maintain airway• Benzodiazepines:
– lorazepam (1-2 mg IV)– diazepam (5-10 mg IV)
• Phenytoin: – 18 mg/kg loading dose, at 25-50 mg/min
infusion with cardiac monitor
• No need for prophylaxis
Primary treatment of AIS
• Supportive care• Aspirin• IV thrombolysis• No role for antithrombotics
Summary
Evaluation• History with time of symptom
onset• Physical exam
– trauma, NIHSS score
• Laboratory evaluation• Non-contrast CT head
Summary
Supportive Care• Secure airway; basic and advanced
methods• Protect C-spine• Assure oxygenation and ventilation• Maximize perfusion, IV fluids• Blood pressures (both arms), treat carefully• Normalize the temperature and glucose • Treat seizure if occurs• Reevaluate