Principals of Neurocritical Care in the Acute Stroke...
Transcript of Principals of Neurocritical Care in the Acute Stroke...
Alexander Y. Zubkov, MD, PhD, FAHA
Clinical Associate Professor of Neurology
Director of Stroke Center
Fairview Southdale Hospital
Minneapolis Clinic of Neurology
Kari Olson, RN, BSN, CNRN
Neuroscience Nurse Clinician
Principals of Neurocritical Care
in the Acute Stroke Patient
DISCLOSURE
Relevant Financial Relationship(s)
• None
Off Label Usage
• None
Objectives
Learning Objectives: Upon completion of this call, participants will be able to:
– Describe Neuro Critical Care management of acute stroke patients.
– Explain advances in neurosurgery for the stroke patient including decompressive hemicraniectomy for malignant cerebral edema
– Describe nursing care guidelines for the pre and post neurosurgical stroke patient
Pressing Issues in Acute Ischemic
Stroke
• Restoring blood flow
• Monitoring for edema and swelling
• Managing risk of bleeding with tPA
• Preventing and minimizing secondary injury
General Care Principles
• Maximize standard medical management– B/P, fever, hyperglycemia, seizure activity
• Neuroprotection
• Improve cerebral blood flow– Induce HTN
– Recanilization with thrombolysis
– Large vessel intra-arterial thombolectomy/lysis
• Prevention of complications
Airway and Mechanical Ventilation
• Management of the airway and mechanical ventilator is different in neurologic critically ill patients.
• Many patients admitted to NICU have normal baseline pulmonary function
• Mode of mechanical ventilation in acutely ill neurologic patient is often limited to intermittent mandatory or assist control modes
• Ventilator dependency is much less common
Airway and Mechanical Ventilation
• Any amount of hypoxia of the injured brain will add a significant damage to the brain.
• Thus, intubation should be preferably performed in the controlled settings, and sometimes it is safest
to perform in the anticipation of the respiratory problems rather than when the respiratory failure
will occur.
Volume Status and Blood Pressure
• Very few patients admitted to NICU are euvolemic and correction of volume status is one the first steps
in the management of critically ill neurological or
neurosurgical patient
• Initial correction of hypovolemia should be done
with crystalloids (normal saline). Glucose containing solutions may precipitate increased lactate
production and secondary brain injury
Volume Status
• 200 mL/hr
• .9% sodium cloride
• Correct insensible loss– GI 250 mL
– Skin 750 mL
– Fever 500 mL/degree C
– Sweating
• Fluid balance 750-1,000 mL/ day excess
• Maintain body weight
• Hematocrit < 55%
• Osmolality <350 mosm/L
• Serum sodium < 150 meq/L
The Importance of Blood Pressure
• Hypertension is a physiological response in stroke
• BP reduction is associated with worse outcome
• BP fluctuations are associated with worse outcome
• BP augmentation may be safe and effective at least in selected cases
Management of Blood pressure
• Current recommendations include cutoff point in treatment of hypertension if systolic pressure is
above 230 mm Hg, or diastolic pressure is above
125 mm Hg, or mean pressure above 130 mm Hg.
• It is reasonable to gradually decrease blood pressure with rapid-acting antihypertensive medications if
mean pressure is getting above 130 mm Hg.
Hypertension: a physiological response to brain
hypoperfusion
• 149 pts monitored for 12 hr after IA thrombolysis
• SBP, DBP and MAP similar before thrombolysis
• 12 hr after thrombolysis, SBP/MAP/DBP lower
in pts with adequate recanalization
• When recanalization failed, BP remained elevatedlonger
Mattle et al. Stroke 2005;36:264-8
Detrimental effect of BP reduction in first 24 hours after stroke onset:
• Prospective assessment of 115 pts evaluated within
24 hr of stroke onset• Mean NIHSS 4.5
• Most common mechanism: cardioembolism (30%)
• Predictors of poor outcome at 3 mo on multivariable
analysis: - Higher NIHSS
(OR 1.55 per 1 point increase in score) - Degree of SBP reduction in first 24 hr
(OR 1.89 per 10% SBP decrease)
Oliveira-Filho et al. Neurology 2003;61:1047-51
The Importance of Blood
Glucose• Hyperglycemia in acute stroke is associated
with:
- Worse functional outcome
- Lower rates of recanalization
- Higher rates of hemorrhagic complications
• Trials of acute intensive glycemic control ongoing
Infections / Fever
• Fever develops in 25-50% of NICU patients.
• 52% percent of fevers were explained by infectious
etiology with most predominant pulmonary pathology.
• Non-infectious etiologies of fever may occur and include reaction to blood products, deep vein
thrombosis, drug fever, postsurgical local tissue injury, pulmonary embolism and central fever with
its extreme autonomic storms (episodes of profuse
sweating, tachycardia, tachypnea, bronchial hypersecretion).
The Importance of Body
Temperature• Fever after acute stroke is associated with
worse functional outcome
• Preliminary evidence suggests that aggressive control of hyperthermia (and perhaps
induced hypothermia in cases of massive brain infarction) may be beneficial
• Rigorous, larger interventional trials needed
Nutrition
• The main goal of nutrition should be to preserve muscle mass, and to provide adequate fluids, minerals and fats
• It is prudent to consider postpyloric feeding in patient with neurological catastrophies, because gastric atony increases the risk of aspiration.
• Enteral feeding should be preferably done by continuous infusion with a volumetric pump.
Seizures
• Acute injury to the cortical structures can
elicit seizures.
• Seizures may be focal or generalized, single or continuous
• Tonic–clonic status epilepticus is commonly
defined as repetitive seizures without full recovery between the episodes, usually with
seizure intervals of 5 to 10 minutes
Seizures
• Nonconvulsive status epilepticus is much difficult to diagnose and likely is less common.
• Clinical hallmarks are decrease in the level of consciousness or fluctuation in responsiveness.
• Patient may have fluttering of the eyelids or eye deviation as only signs of nonconvulsive status epilepticus.
Seizure Assessment
• Continuous clinical assessment
• Continuous vEEG monitorin
– 20 minute EEG will demonstrate 15% of
seizures
– 60 minute EEG – 50%
– 24 hours monitoring – close to 90%
Seizure Management
• Benzodiazepins– Ativan 4 mg IV push
• Antiepileptic medications– Dilantin may be toxic for the acutely injured brain
– Depakote may cause severe platelet dysfunction and bleeding
– Keppra seems to avoid significant side effects and used widely in NICU
Seizure Management
• Failure of lorazepam and fosphenytoin in adequate doses to control seizures indicates transition to refractory status epilepticus.
• At this point either increasing doses of barbiturates or midazolam should be used for treatment.
• Propofol is another alternative but high dosis are needed. Propofol infusion syndrome – sudden cardiovascular collapse with metabolic acidosis-is a serious complication that limits the routine use of this otherwise very effective medication.
Anticoagulation• Neurological patients has a higher incidence of DVT due to
lack of mobility in the affected limbs, associated with neurological injury.
• Clinically apparent DVT was reported in 1.7% to 5% of patients with ischemic stroke
• Subclinical DVT occurred in 28 to 73%, mostly in the paralyzed extremity
• 5% of the patient with ICH died of pulmonary embolism (PE) within the first 30 days.
Anticoagulation
• Only mechanical methods (intermittent pneumatic compression with or without elastic stockings) should the standard of care.
• The use of unfractionated heparin was left on the discretion of the practitioner
• One study in TBI patients demonstrated no increase risk of hemorrhage in patients treated with unfractionated heparin within 72 hours
Large Hemispheric Stroke Issues
• High risk for deterioration in first 24-72
hours
– Neurologic causes: edema, hemorrhagic
transformation, restroke
– Systemic causes: fever, infection, hypotension,
hypoxia, hypercarbia
Malignant MCA Syndrome
• Malignant brain edema
– Mortality up to 80%
– Starts days 1-3
– Peaks days 3-5
– Subsides by 2 weeks
Who is at Risk for Developing
Malignant MCA Syndrome?Clinical Picture:
• hemispheric syndrome with hemiparesis, hemianesthesia
• eye deviation
• those requiring early intubation for airway protection
• global asphasia
• somnolence
Radiographic Picture• CT findings in 1st 6 hours
• Large early hypodensity• Loss of gray/white matter
distinction
• Hyperdense MCA sign
• CT findings at 24 hours• Mass effect
Intracranial pressure
Monro-Kelly doctrine
ICP depends on the
volumes of blood,
cerebrospinal fluid and brain to be in the balance.
Intracranial pressure
• CSF shift from ventricular or subarachnoid space into spinal compartment.
• Reduction of intracranial blood volume achieved by collapsing of veins and dural sinuses and by changes in the diameter of cerebral vessels.
• If the limits of compensatory mechanisms are exceeded, minimal increase in the intracranial volume will lead to precipitous rise of ICP.
Intracranial Pressure
• Intracranial pressure monitoring is an integral part of NICU.
• The indications for placement of ICP monitors include GCS < 8, severe traumatic brain injury, massive cerebral edema from infarction
Intracranial Pressure Management
• Head position should be neutral to reduce
any possible compression of jugular veins.
• Head elevation of 30º is considered standard
• Patients should be made comfortable, avoid pain, bladder distention, and agitation,
because all of them might increase ICP.
Intracranial Pressure Management
• Hyperventilation
– Aggressive hyperventilation might decrease cerebral blood flow to the levels approaching
ischemia.
– Hyperventilation should only be used as a bridge
measure while other means of ICP control are
instituted
Intracranial Pressure Management
• Osmotic diuresis – mainstay of the therapy
– Mannitol is not only facilitates movement of extracellular
water, but also might be increasing CSF absorption
• The effect is apparent within 15 minutes and failure to respond
to mannitol is usually a bad prognostic sign
• 100 grams IV over 30 minutes
• 50 grams IV q6h with osmolality monitoring.
– Hypertonic Saline
• 3% NaCl - continuous infusion
• 7.5% NaCl - mostly used in trauma centers
• 23.4% saline
• Sixty-eight patients met criteria for TTH and received 23.4% saline, and there were a total of 76 TTH events in these patients.
• The 23.4% saline was administered as a bolus of 30 mL in 65 events (85.5%) and 60 mL in 11 events (14.5%).
Neurology, Mar 2008; 70: 1023 - 1029
Hypertonic Saline Effect
• Clinical reversal of TTH occurred in 57/76 events (75.0%).
• Median (IQR) GCS increased from 4(3-5) at the time of
herniation to 6(4-7) (p<0.01) 1 hour and 7(5-9) 24 hours
following TTH (p<0.001).
Neurology, Mar 2008; 70: 1023 - 1029
Intracranial Pressure Management
• Hypothermia
– Need to continue the study of safety and effectiveness in the Neuro ICU.
– Guidelines needed for best practice temperature thresholds and rates of rewarming.
Decompressive Hemicraniectomy
• Allows for the expansion of edematous tissue outside the cranial vault
• Decreases mortality and disability
• Issues:– Patient Selection
– Timing of surgery
– Dominant vs. non-dominant hemisphere strokes
Outcome at 1 year by treatment group
for all three studies combined
Lancet Neurology, 8( 7); 603-604, 2009
Subarachnoid hemorrhage
• Hydration with normal saline should be started immediately and patient should receive at least 2-3L of fluids in the first 24 hours.
• Attention should be paid to possible neurogenic pulmonary edema and fluid management should be adjusted accordingly.
• Cardiac stunning might occur in the poor grade SAH and might contribute to pulmonary edema
• Management of hypertension depends on the
stage of the treatment.
• In the patients with unsecured aneurysm we tend to keep mean arterial pressure below 100
mm Hg.
• In patients who underwent aneurysmal repair, mean blood pressure should be liberalized up
to 130 mm Hg.
Subarachnoid hemorrhage
Subarachnoid hemorrhage
• Nutrition usually delays to the second day. Nausea and vomiting are common on the first day, in addition to gastroparesis in more
severely impaired patients
• Deep vein thrombosis prophylaxis should utilize mechanical means only.
• Gastric ulcer prophylaxis is important in all
patients due to high incidence of stress ulcers.
Subarachnoid hemorrhage
• Stool softeners should be used in all patients to prevent straining, which may lead to rerupture of the aneurysm.
• Indwelling catheters should be used to close monitoring in outputs due to potential of the development of SIADH.
• Headache may be relieved by acetaminophen with codeine or tramadol.
• Vomiting should be aggressively treated.
Subarachnoid hemorrhage
• Deterioration in patients with SAH can be
delayed and related to rebleeding, hydrocephalus, vasospasm, or enlargement of
frontal or temporal intraparenchymal hematoma.
Intracerebral hemorrhage
• Hemorrhages have a potential of enlargement in about a third of the patients and management should be directed towards supportive measures.
• Very aggressive decrease of blood pressure may precipitate ischemia
• Comatose patients could benefit from the monitoring in intracranial pressure.
• Intracranial pressure should remain below 20 mm Hg and cerebral perfusion pressure must remain in the range of 60 to 80 mm Hg to provide adequate cerebral blood flow
AAICH
• Anticoagulation-associated intracerebral
hemorrhages should be immediately reversed with fresh frozen plasma and vitamin K.
• Factor VIIa - works within 10 minutes
– It is short lived factor.
– Treatment should be followed by administration
of FFP and Vitamin K
– INR should be monitored for at least 72 hours
Time is Brain
• For every minute’s delay, the brain loses:– 1.9 million neurons;
– 14 billion synapses;
– 7.5 miles of myelinated fibers.
• If a stroke runs its full course – an estimated 10 hours on average – the brain loses:– 1.2 billion neurons;
– 8.3 trillion synapses;
– 4,470 miles of myelinated fibers.
Stroke 2006;37:263-266
Nursing management of Acute Stroke
• Airway management/ventilator management
• Assessment and evaluation of neurologic status to detect patient deterioration
• Blood pressure management
• General supportive care and prevention of complications associated with:– Dysphagia, HTN, hyperglycemia, dehydration, malnourishment,
fever, cerebral edema, infection, and DVT, immobility, falls, skin care, bowel and bladder dysfunction.
Nursing Management of Acute Stroke
• Coordination of interdisciplinary team and
plan of care
• Support and counsel for patient & family
Intensive Nursing Management
• Monitor for bleeding complications after tPA
– ICH-Hemorrhagic transformation
– retroperitoneal bleed, genitourinary and
gastrointestinal hemorrhages
– Patients over age of 80 with higher NIHSS score
at greater risk of ICH
Intensive Nursing Management
• Management of suspected ICH after tPA
– Notify physician, possible neurosurgery consult
– Stop tPA infusion
– Prepare for stat brain imaging, lab, type and cross
– Prepare to administer platelets, cryoprecipitate, FFP
– Increase frequency of nursing assessment
Intensive Nursing Management
Cerebral Edema after stroke
Usually peaks 3-5 days after stroke
Can be an issue in first 24 hours in cerebellar infarct and younger stroke patients
If not detected and treated can lead to increased intracranial pressure, brain herniation and
death
Recognizing Increased ICP
• Early signs:
– Decreased LOC
– Deterioration in motor
function
– Headache
– Changes in vital signs
• Late signs
– Pupillary abnormalities
– Changes in respiratory
pattern
– Changes in ABG’s
Nursing Care of the Decompressive
Hemicraniectomy Patient
• Airway management adequate O2 saturation
• Preventing increased ICP and providing supportive care.
• Hourly vitals/neuros including ICP, CPP, CVP.
• Maintaining BP to ensure adequate CPP• Seizure precautions
• Antibiotic prophylaxis
Nursing Care of the Decompressive
Hemicraniectomy Patient
• Place a sign on bed to alerting care providers which side of the skull is missing the bone flap
• Do not turn patients onto side of missing flap
• Monitor hemicraniectomy site for changes in
appearance- bulging, inflammation, CSF leakage
• Fit with head gear to protect surgical site when up
Decompressive Hemicraniectomy
• Bone flap stored in a Bone Bank or sewn into
a pouch in patient’s abdomen.
• Bone replaced at around 3 months from the time of the infarction.
Team Work
• Key to the care of the NICU patient
• Stabilization
• Prevention of complications
• Monitoring neuro status
• Family support and education
Resources
• Adams, H. et al (2007). Guidelines for the Early Management of Adults with Acute Ischemic Stroke. Stroke 38, 1655-1711.
• Ropper, A.H., Gress, D.R., Diringer, M.N., Green, D.M. , Mayer, S.A. , Bleck,
T.P. Neurological and Neurosurgical Intensive Care. Fourth edition. Lippincott Williams & Wilkins.2004. Philadelphia, PA
• Summers, et al. (2009) Comprehensive Overview of Nursing and Interdisciplinary
Care of the Acute Ischemic Stroke Patient. Stroke 40, 2911-2944.
• Tazbir, J., Marthaler, M.T., Moredich, C., Keresztes, P. Decompressive Hemicraniectomy with Duraplasty: A treatment for Large-Volume Ischemic
Stroke. Journal of Neuroscience Nursing. August 2005. 37(4).
• Wojner Alexandrof, A. W., Hyperacute Ischemic Stroke Management:Reperfusion and Evolving Therapies. Critical Care Nurse Clinician
North America. 21(2009) 451-470.