Approach NIH STROKE Scale

Approach  NIH STROKE Scale

The NIH Stroke Scale (NIHSS) ( The National Institutes of Health Stroke Scale) is a tool used by healthcare providers to objectively quantify the impairment caused by a stroke. It composed of 11 items, each of which scores a specific ability between a 0 and 4.

 For each item, a score of 0 typically indicates normal function in that specific ability, while a higher score is indicative of some level of impairment.

NIHSS total score is based on the summation of 4 factors. These factors are left and right motor function and left and right cortical function. The NIHSS assesses each of these specific functions by the stroke scale item listed in the chart below.

Left Cortical	Right Cortical	Right Motor	Left Motor
LOC Questions	Horizontal Eye Movement	Right Arm Motor	Left Arm Motor
LOC Commands	Visual Fields	Right Leg	Left Leg
Language	Extinction and Inattention	Dysarthria
	Sensory

The individual scores from each item are summed in order to calculate a patient's total NIHSS score. The maximum possible score is 42, with the minimum score being a 0. 

Score	Stroke Severity
0	No Stroke Symptoms
0-4	Minor Stroke
5-15	Moderate Stroke
16-20	Moderate to Severe Stroke
21-42	Severe Stroke

NIHSS Scoring System

1a: Level of Consciousness (LOC) 

• 0 = Alert; keenly responsive. 
• 1 = Not alert; but arousable by minor stimulation to obey, answer, or respond. 
• 2 = Not alert; requires repeated stimulation to attend, or is obtunded and requires strong or painful stimulation to make movements (not stereotyped). 
• 3 = Responds only with reflex motor or autonomic effects, or totally unresponsive, flaccid, and areflexic. 

1b: LOC Questions

The patient is asked the month and his/her age

• 0 = Answers both questions correctly. 
• 1 = Answers one question correctly / Endotracheal intubation / Dysarthria. 
• 2 = Answers neither question correctly / Aphasia. 

1b: LOC Commands

The patient is asked to open and close the eyes and then to grip and release the non-paretic hand

• 0 = Performs both tasks correctly. 
• 1 = Performs one task correctly. 
• 2 = Performs neither task correctly. 

2: Best GazeTest horizontal eye movements

• 0 = Normal. 
• 1 = Partial gaze palsy; gaze is abnormal in one or both eyes, but forced deviation or total gaze paresis is not present. 
• 2 = Forced deviation, or total gaze paresis is not overcome by the oculocephalic maneuver

3: VisualVisual field testing by confrontation. 

• 0 = No visual loss. 
• 1 = Partial hemianopia. 
• 2 = Complete hemianopia. 
• 3 = Bilateral hemianopia (blind including cortical blindness)

4: Facial PalsyShow teeth, raise eyebrows, close eyes

• 0 = Normal symmetrical movements. 
• 1 = Minor paralysis (flattened nasolabial fold, asymmetry on smiling). 
• 2 = Partial paralysis (total or near-total paralysis of lower face). 
• 3 = Complete paralysis of one or both sides (absence of facial movement in the upper and lower face)

5: Motor Arm

The limb is placed in the appropriate position: extend the arms (palms down) 90 degrees (if sitting) or 45 degrees (if supine)

5a = left arm; 5b = right arm. 

• 0 = No drift; limb holds 90 (or 45) degrees for full 10 seconds. 
• 1 = Drift; limb holds 90 (or 45) degrees, but drifts down before full 10 seconds; does not hit bed or other support. 
• 2 = Some effort against gravity; limb cannot get to or maintain (if cued) 90 (or 45) degrees, drifts down to bed, but has some effort against gravity. 
• 3 = No effort against gravity; limb falls. 
• 4 = No movement.

UN = Amputation or joint fusion, explain why untestable. 

6: Motor Leg

The limb is placed in the appropriate position: hold the leg at 30 degrees (always tested supine)

6a = left leg; 6b = right leg. 

• 0 = No drift; leg holds 30-degree position for full 5 seconds. 
• 1 = Drift; leg falls by the end of the 5- second period but does not hit the bed. 
• 2 = Some effort against gravity; leg falls to bed by 5 seconds but has some effort against gravity. 
• 3 = No effort against gravity; leg falls to bed immediately. 
• 4 = No movement. 

UN = Amputation or joint fusion, explain why untestable. 

7: Limb AtaxiaThis item is aimed at finding evidence of a unilateral cerebellar lesion. 

Test with eyes open.

• 0 = Absent. 
• 1 = Present in one limb. 
• 2 = Present in two limbs. 

UN = Amputation or joint fusion, explain why untestable. 

8: Sensory

Sensation or grimace to pinprick when tested, or withdrawal from noxious stimulus in the obtunded or aphasic patient. 

• 0 = Normal; no sensory loss. 
• 1 = Mild-to-moderate sensory loss; patient feels pinprick is less sharp or is dull on the affected side; or there is a loss of superficial pain with pinprick, but patient is aware of being touched. 
• 2 = Severe or total sensory loss; patient is not aware of being touched in the face, arm, and leg. 

9: Best Language 

• 0 = No aphasia; normal. 
• 1 = Mild-to-moderate aphasia; some obvious loss of fluency or facility of comprehension, without significant limitation on ideas expressed or form of expression. Reduction of speech and/or comprehension, however, makes conversation about provided materials difficult or impossible. 
• 2 = Severe aphasia; all communication is through fragmentary expression; great need for inference, questioning, and guessing by the listener. Range of information that can be exchanged is limited; listener carries burden of communication. 
• 3 = Mute, global aphasia; no usable speech or auditory comprehension (or patient in coma). 

10: Dysarthria 

• 0 = Normal. 
• 1 = Mild-to-moderate dysarthria; patient slurs at least some words and, at worst, can be understood with some difficulty. 
• 2 = Severe dysarthria; patient’s speech is so slurred as to be unintelligible in the absence of or out of proportion to any dysphasia, or is mute/anarthric. 

UN = Intubated or other physical barrier, explain why untestable. 

11: Extinction and Inattention(formerly called Neglect) 

• 0 = No abnormality. 
• 1 = Visual, tactile, auditory, spatial, or personal inattention, or extinction to bilateral simultaneous stimulation in one of the sensory modalities. 
• 2 = Profound hemi-inattention or extinction to more than one modality; does not recognize own hand or orients to only one side of space.

Indication for trombolysis

All patients presented a NIH stroke scale-score (NIHSS) of 5–22 . These patients were divided into three groups according to clinical severity: NIHSS: 5–10 (mild-moderate stroke), 11–15 (moderate-severe stroke), >15 (severe stroke) 

• Consider for acute ischaemic CVA within 3 hours of onset after exclusion of haemorrhage
• Most appropriately used in a stroke center or as part of a randomised controlled trial
• Used up to 4.5 hours in some centers based on ECASS-III

Dose and mode of action 

0.9mg/kg alteplase (r-TPA) (maximum 90mg) over 60 minutes (10% given as a bolus). Alteplase selectively binds to fibrin and converts plasminogen -> plasmin -> degradation of fibrin matrix

Absolute Contraindications to Thrombolysis

• Uncertainty about time of stroke onset (e.g. patients awakening from sleep).
• Coma or severe obtundation with fixed eye deviation and complete hemiplegia.
• Hypertension: systolic blood pressure ≥ 185mmHg; or diastolic blood pressure >110mmHg on repeated measures prior to study. (if reversed, patient can be treated)
• Clinical presentation suggestive of subarachnoid haemorrhage even if the CT scan is normal.
• Presumed septic embolus.
• Patient having received a heparin medication within the last 48 hours and has an elevated Activated Prothrombin Time (APTT) or has a known hereditary or acquired haemorrhagic diathesis
• INR >1.7
• Known advanced liver disease, advanced right heart failure, or anticoagulation, and INR > 1.5 (no need to wait for INR result in the absence of the former three conditions).
• Known platelet count <100,000 uL.
• Serum glucose is < 2.8 mmol/l or >22.0 mmol/l.

Relative Contraindications to Thrombolysis

• Severe neurological impairment with NIHSS score >22.
• Age >80 years.
• CT evidence of extensive middle cerebral artery (MCA) territory infarction (sulcal effacement or blurring of grey-white junction in greater than 1/3 of MCA territory).
• Stroke or serious head trauma within the past three months where the risks of bleeding are considered to outweigh the benefits of therapy.
• Major surgery within the last 14 days (consider intra-arterial thrombolysis).
• Patient has a known history of intracranial haemorrhage, subarachnoid haemorrhage, known intracranial arteriovenous malformation or previously known intracranial neoplasm
• Suspected recent (within 30 days) myocardial infarction.
• Recent (within 30 days) biopsy of a parenchymal organ or surgery that, in the opinion of the responsible clinician, would increase the risk of unmanageable (e.g. uncontrolled by local pressure) bleeding.
• Recent (within 30 days) trauma with internal injuries or ulcerative wounds.
• Gastrointestinal or urinary tract haemorrhage within the last 30 days or any active or recent haemorrhage that, in the opinion of the responsible clinician, would increase the risk of unmanageable (e.g. by local pressure) bleeding.
• Arterial puncture at non-compressible site within the last 7 days.
• Concomitant serious, advanced or terminal illness or any other condition that, in the opinion of the responsible clinician would pose an unacceptable risk.
• Minor or Rapidly improving deficit.
• Seizure: If the presenting neurological deficit is deemed due to a seizure.
• Pregnancy is not an absolute contraindication. Consider intra-arterial thrombolysis.

STOP the rt-PA infusion if: 

•  Anaphylaxis 
•  BP systolic <100 mmHg 
•  BP systolic rises to >180/105 mmHg sustained after 5 minutes, or associated with neurological deterioration of any sort 
•  Major systemic bleeding 
•  Neurological deterioration of 2 points on GCS

Post STROKE Thrombolysis Care General management 

•  Pulse oximetry - maintain O2 saturations above 95%. 
•  Maintain normal temperature. Paracetamol if temp > 370 C. 
•  Blood Glucose: Maintain blood glucose < 10 mmol/l using IV insulin if necessary. 
•  DVT prophylaxis –ideally with automates spontaneous compression devices. 
•  Mobilise in first 24 hours if tolerated 
•  Risks and benefits of all invasive procedures should be carefully considered.. 
•  No urinary catheters for at least 1 hour after infusion ended if possible. 
•  Falls Risk Assessment & Prevention measures. 
•  No aspirin, clopidogrel, dipyridamole or anticoagulant (heparin, warfarin, NOAC’s) for 24 hours. 
•  Hydration / Nutrition 

A non-contrast CT brain should be performed 24-36 hours post thrombolysis for all patients. If no bleeding, Aspirin can be started. 

Discussion ( Life In Fast Lane Blog )

• Despite incorporation into clinical guidelines and widespread adoption by the neurological community, the evidence for stroke thrombolysis is weak
• there is a preponderance of negative studies and the few positive studies have methodological laws, are subject to bias and in turn make subsequent meta-analysis unreliable
• continued use of stroke thrombolysis outside the setting of RCTs is a cause for concern and should be considered an experimental therapy, but future studies seem unlikely now
• other strategies involving clot retrieval or imaging to identify patients those suitable for treatment may hold more promise that crude time-based clinical approaches as it is likely that some patients do benefit from thrombolysis