NIHSS и Прогноза след Инсулт: Функционален Изход и mRS
Изходният NIHSS е един от най-силните независими предиктори на функционалния изход след остър исхемичен инсулт. Прогностичната му стойност нараства, когато се съчетае с възрастта, локализацията на лезията, реперфузията и динамиката на скора през първите 24 часа. Прогнозата обаче винаги е вероятностна и не бива да се използва като единствена основа за ограничаване на лечението.
NIHSS
National Institute of Health Stroke Scale
No stroke symptoms
0
1. a) Level of Consciousness
Alert; keenly responsive
The investigator must choose a response if a full evaluation is prevented by such obstacles as an endotracheal tube, language barrier, orotracheal trauma/bandages. A 3 is scored only if the patient makes no movement (other than reflexive posturing) in response to noxious stimulation.
1. b) Ask for the current month and his/her age
Both questions correct
The answer must be correct - there is no partial credit for being close. It is important that only the initial answer be graded and that the examiner not "help" the patient with verbal or non-verbal cues.
1. c) Ask to blink eyes and squeeze hands
Performs both tasks correctly
Substitute another one step command if the hands cannot be used. Credit is given if an unequivocal attempt is made but not completed due to weakness. If the patient does not respond to command, the task should be demonstrated to him or her (pantomime), and the result scored (i.e., follow s none, one or two commands). Patients with trauma, amputation, or other physical impediments should be given suitable one-step commands. Only the first attempt is scored.
2. Test horizontal extraocular movements
Normal
If a patient has an isolated peripheral nerve paresis(CN III, IV or VI), score a 1. Gaze is testable in all aphasic patients. Patients with ocular trauma, bandages, pre-existing blindness, or other disorder of visual acuity or fields should be tested with reflexive movements, and a choice made by the investigator. Establishing eye contact and then moving about the patient from side to side will occasionally clarify the presence of a partial gaze palsy.
3. Test visual fields
No visual loss
Visual fields (upper and lower quadrants) are tested by confrontation, using finger counting or visual threat, as appropriate. Patients may be encouraged, but if they look at the side of the moving fingers appropriately, this can be scored as normal. If there is unilateral blindness or enucleation, visual fields in the remaining eye are scored. Score 1 only if a clear-cut asymmetry, including quadrantanopia, is found.
4. Test facial palsy
Normal (symmetrical movements)
Ask – or use pantomime to encourage – the patient to show teeth or raise eyebrows and close eyes. Score symmetry of grimace in response to noxious stimuli in the poorly responsive or non-comprehending patient. If facial trauma/bandages, orotracheal tube, tape or other physical barriers obscure the face, these should be removed to the extent possible.
5. a) Test left arm motor drift
No drift for 10 Seconds
The limb is placed in the appropriate position: extend the arms (palms down) 90 degrees (if sitting) or 45 degrees (if supine). Drift is scored if the arm falls before 10 seconds. The aphasic patient is encouraged using urgency in the voice and pantomime, but not noxious stimulation. Each limb is tested in turn, beginning with the non-paretic arm. Only in the case of amputation or joint fusion at the shoulder, the examiner should record the score as untestable (UN).
5. b) Test right arm motor drift
No drift for 10 Seconds
The limb is placed in the appropriate position: extend the arms (palms down) 90 degrees (if sitting) or 45 degrees (if supine). Drift is scored if the arm falls before 10 seconds. The aphasic patient is encouraged using urgency in the voice and pantomime, but not noxious stimulation. Each limb is tested in turn, beginning with the non-paretic arm. Only in the case of amputation or joint fusion at the shoulder, the examiner should record the score as untestable (UN).
6. a) Test left leg motor drift
No drift for 5 seconds
The limb is placed in the appropriate position: hold the leg at 30 degrees (always tested supine). Drift is scored if the leg falls before 5 seconds. The aphasic patient is encouraged using urgency in the voice and pantomime, but not noxious stimulation. Each limb is tested in turn, beginning with the non-paretic leg. Only in the case of amputation or joint fusion at the hip, the examiner should record the score as untestable (UN), and clearly write the explanation for this choice.
6. b) Test right leg motor drift
No drift for 5 seconds
The limb is placed in the appropriate position: hold the leg at 30 degrees (always tested supine). Drift is scored if the leg falls before 5 seconds. The aphasic patient is encouraged using urgency in the voice and pantomime, but not noxious stimulation. Each limb is tested in turn, beginning with the non-paretic leg. Only in the case of amputation or joint fusion at the hip, the examiner should record the score as untestable (UN), and clearly write the explanation for this choice.
7. Test limb ataxia
No ataxia
This item is aimed at finding evidence of a unilateral cerebellar lesion. Test with eyes open. In case of visual defect, ensure testing is done in intact visual field. The finger-nose-finger and heel-shin tests are performed on both sides, and ataxia is scored only if present out of proportion to weakness. In case of blindness, test by having the patient touch nose from extended arm position.
8. Test sensation
Normal (no sensory loss)
Sensation or grimace to pinprick when tested, or withdrawal from noxious stimulus in the obtunded or aphasic patient. Only sensory loss attributed to stroke is scored as abnormal and the examiner should test as many body areas (arms [not hands], legs, trunk, face) as needed to accurately check for hemisensory loss.
9. Test language
No aphasia; normal
If visual loss interferes with the tests, ask the patient to identify objects placed in the hand, repeat, and produce speech. The intubated patient should be asked to write. The examiner must choose a score for the patient with stupor or limited cooperation, but global aphasia answer should be used only if the patient is mute and follows no one-step commands.
10. Test dysarthria
Normal
If patient is thought to be normal, an adequate sample of speech must be obtained by asking patient to read or repeat words. If the patient has severe aphasia, the clarity of articulation of spontaneous speech can be rated. Only if the patient is intubated or has other physical barriers to producing speech, the examiner should record the score as untestable. Do not tell the patient why he or she is being tested.
11. Test extinction and inattention
No abnormality
Sufficient information to identify neglect may be obtained during the prior testing. If the patient has a severe visual loss preventing visual double simultaneous stimulation, and the cutaneous stimuli are normal, the score is normal. If the patient has aphasia but does appear to attend to both sides, the score is normal. The presence of visual spatial neglect or anosagnosia may also be taken as evidence of abnormality. Since the abnormality is scored only if present, the item is never untestable.
Изходен NIHSS и Функционален Изход
В анализа на проучването TOAST (Adams et al., 1999) изходният NIHSS силно предсказва изхода на 7-ия ден и на 3-тия месец:
- Всяка допълнителна точка намалява вероятността за отличен изход — с около 24 % на 7-ия ден и с около 17 % на 3-тия месец
- NIHSS ≤ 6 се свързва с висока вероятност за добро възстановяване
- NIHSS ≥ 16 се свързва с висока вероятност за смърт или тежка инвалидизация
- Прогностичната стойност на един и същ скор зависи от подтипа на инсулта (напр. лакунарен срещу кардиоемболичен)
Модифицирана Скала на Ранкин (mRS)
Функционалният изход в проучванията се измерва най-често с mRS на 90-ия ден:
| mRS | Описание |
|---|---|
| 0 | Без симптоми |
| 1 | Без значима инвалидизация въпреки симптомите |
| 2 | Лека инвалидизация, самостоятелен в ежедневието |
| 3 | Умерена инвалидизация, нуждае се от известна помощ, ходи самостоятелно |
| 4 | Умерено тежка инвалидизация, не може да ходи без помощ |
| 5 | Тежка инвалидизация, прикован на легло, нуждае се от постоянни грижи |
| 6 | Смърт |
„Добър изход" обикновено се определя като mRS 0–2 (функционална независимост), а „отличен изход" — като mRS 0–1.
NIHSS на 24 Часа
NIHSS, измерен 24 часа след началото на лечението, отразява ефекта на реперфузията и ранните усложнения. В анализи на проучвания с тромболиза и тромбектомия той предсказва 90-дневния изход по-добре от изходния скор. Бързото подобрение (напр. с ≥ 8 точки или до 0–1) се разглежда като маркер за успешна реперфузия.
NIHSS и Риск от Кръвоизлив
По-високият изходен NIHSS е свързан с по-голям риск от симптоматичен вътречерепен кръвоизлив след тромболиза, тъй като отразява по-обширна исхемия. Въпреки това абсолютната полза от реперфузията при тежките инсулти е значима, поради което висок NIHSS сам по себе си не е противопоказание за лечение.
Фактори, Които Модифицират Прогнозата
- Възраст — по-високата възраст влошава изхода при един и същ NIHSS
- Локализация — десностранните лезии може да получат по-нисък NIHSS при сходен обем на инфаркта; задноямковите инсулти са подценени
- Реперфузия — постигната реканализация значително подобрява изхода
- Предшестващ функционален статус (mRS преди инсулта)
- Обем на инфаркта на образната диагностика
Често Задавани Въпроси
Може ли пациент с NIHSS 20 да се възстанови добре? Да. Особено при бърза и успешна реперфузия пациенти с тежък изходен дефицит могат да постигнат функционална независимост. Затова високият NIHSS не бива да води до терапевтичен нихилизъм.
Какъв NIHSS при изписване се свързва с добра прогноза? Ниският NIHSS при изписване е свързан с по-добър дългосрочен изход, но функционалната независимост се оценява по-точно с mRS и Barthel индекс.
Защо да не прогнозираме само по изходния NIHSS? Изходният скор не отчита отговора на лечението, усложненията и рехабилитационния потенциал. Серийните оценки и NIHSS на 24 часа са по-информативни.
Източници
- Adams HP Jr, et al. Baseline NIH Stroke Scale score strongly predicts outcome after stroke: a report of the Trial of Org 10172 in Acute Stroke Treatment (TOAST). Neurology. 1999;53(1):126–131.
- Brott T, et al. Measurements of acute cerebral infarction: a clinical examination scale. Stroke. 1989;20(7):864–870.
- van Swieten JC, et al. Interobserver agreement for the assessment of handicap in stroke patients. Stroke. 1988;19(5):604–607.
