General Emergent Management of Patients with Stroke, Including Blood Pressure Management

1. General Emergent Management of Patients with Stroke, Including Blood Pressure Management

2. 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

3. Goals of Acute Supportive Care Assure optimal perfusion and oxygenation • Protect the C-spine • Secure the airway • Support oxygenation and ventilation • Assure appropriate circulation

4. 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

5. 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

6. Past Medical History • Medications: • diuretic, antihypertensive, antithrombotic • Risk Factors: hypertension TIA smoking previous stroke diabetes atrial fibrillation African-American carotid artery disease

7. 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

8. 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

9. Stroke Scales • NIH stroke scale 0-42 0-5 mild/minor in most patients 5-15 moderate 15-20 moderately severe > 20 very severe underestimates volume of infarct in non-dominant (R) hemispheric strokes

10. Diagnostic Testing • Laboratory studies • CBC, differential, platelets • electrolyte profile, glucose (finger stick) • INR, aPTT • Troponin • EKG • CXR

11. 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

12. 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

13. ECT 2 hours 24 hours

14. Other Imaging Modalities • MRI • standard • DWI/PWI • Xenon CT • Perfusion CT • CT Angiography

15. Differential Diagnosis • Deciphered by history, PE, diagnostics • DDx: TIA vascular disorders seizure infections (endocarditis) trauma complex migraine mass lesions metabolic abnormalities

16. Stroke Vital Signs Airway Breathing Circulation C-spine Glucose Temperature

17. 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

18. Oxygenation and Ventilation • Respiratory rate and depth • Signs of fatigue - Paradoxical respirations • Breath sounds - (CHF, pneumonia, COPD) • Supplemental O2 with O2sat > 95% • Support with Basic airway techniques • Ventilatory support as required

19. Basic airway techniques • Foreign body removal • Suction with rigid suction device • Positioning • jaw thrust • chin lift • Nasal airway • Bag valve mask

20. 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.

21. 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

22. Circulation • Goal: maintain cerebral perfusion • Optimize cardiovascular status • Monitor and reevaluate

23. Circulation • Evaluate cardiac history and status • Cardiac output • preload • afterload • contractility • stroke volume

24. 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

25. 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

26. Vascular Access • Two peripheral IVs • Use .9NS or .45 NS unless hypotensive • Use .9NS if hypotensive • Replace blood products as indicated

27. 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

28. Autoregulationof Cerebral Blood Flow

29. 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]B3 • NSA: 220/115

30. Hypertension - Ischemic Stroke • Drugs - short acting, titrate • Labetalol IV: 10-20 mg increments, double dose Q 20 min, max cumulative dose 300mg • Enalapril Oral: 2.5 - 5.0 mg/day, max 40mg/day IV : 0.625-1.25 mg IV Q 6hrs, max 5.0 Q 6 hrs

31. Hypertension -Ischemic Stroke • Nitroglycerine Paste: 1-2 inches to skin IV Drip: 5mcg/min, increase in increments of 5-10mcg every 3-5 min • Nitroprusside IV Drip: 0.3 - 10 mcg/min/kg Continuos BP monitoring check thiocyanate levels • AVOID NIFEDIPINE

32. 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

33. 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

34. 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

35. 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

36. 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

37. 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

38. Seizures • Occur in 5% of acute strokes • Usually generalized tonic-clonic • Possible causes: severe strokes cortical involvement unstable tissue at risk spreading depolarizations hx of seizure disorder

39. 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

40. Primary treatment of AIS • Supportive care • Aspirin • IV thrombolysis • No role for antithrombotics

41. Summary Evaluation • History with time of symptom onset • Physical exam • trauma, NIHSS score • Laboratory evaluation • Non-contrast CT head

42. 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