Coma Flashcards
1
Q
Delirium definition
A
fluctuating confusion, inattention, misperceptions (illusions or hallucinations).
2
Q
Stupor definition
A
a sleep-like state from which the patient can be aroused only by vigorous stimuli.
3
Q
Coma definition
A
a sleep-like state where the patient is unresponsive to external stimuli, and there are no sleep-wake cycles. Usually lasts no more than 4 weeks. GCS 8 or less.
4
Q
Glasgow Coma Scale
A
- Motor
- 1 = no response
- 2 = extension (decerebrate)
- 3 = flexion (decort)
- 4 = normal flexion/withdrawal
- 5 = localizes pain
- 6 = obeys command
- Verbalization
- 1 = no response
- 2 = incomprehensible sounds
- 3 = innapropriate words
- 4 = confused
- 5 = oriented
- Eye opening
- 1 = no eye opening
- 2 = opens to pain
- 3 = opens to voice
- 4 = spontaneous eye opening
5
Q
Types of abnormal postures
A
- Decorticate (flexion) – upper extremity flexion with lower extremity extension (suggests lesion at hemispheres)
- Decerebrate (extension)– upper extremity extension with lower extremity extension (suggests lesion at upper brainstem)
- Prognosis of decerebrate is worse than decorticate
6
Q
“Determination of Death”
A
- Pt. has sustained irreversible cessation of circulatory and respiratory functions; or
- Pt. has sustained irreversible cessation of all functions of the entire brain, including the brainstem.
7
Q
Criteria of brain death
A
- unresponsiveness
- deep coma; GCS = 3
- absent motor responses during application of painful stimulus
- spinal reflexes may be present
- seizures or flex/extend posturing are not
- brainstem reflexes are absent
- pupils, corneals, oculocephalic, oculovestibular, cough, gag, respirations
- apnea test is positive
- specific vitals
- core body temp 32.2 C (90 F)
- no toxic explanation for low neuro state
- adequate BP & pulse (SBP 90, P>50)
8
Q
Corneal reflex test
A
- Touch cornea with tissue ==> (normal) blink response
- Tests CNs V and VII
- @ brain death: no blink response in either ey
9
Q
Cold Caloric Test
A
- “oculovestibular reflex”
- Test: Flush each external auditory canal with 20 ml ice water x 2 and observe
- normal response: eyes turn toward theipsilateral ear, with horizontal nystagmus to the contralateral ear.
- Tests CNs VIII, III, IV and VI
- @ brain death: no eye movements
10
Q
Cough reflex test
A
- Test: Suction the trachea at the carina.
- normal response: cough
- Tests CN X
- @ brain death: no cough response
11
Q
Gag reflex test
A
- Test: touch the oropharynx with Q-tip ==> (normal) gag
- Tests CNs IX and X
- @ brain death: no movement of the oral structures.
12
Q
Situations in which organ donation occurs
A
- Donation after Brain Death
- Donation after Cardiac Death
- **patient must be declared dead prior to organ harvesting
13
Q
Characteristics of consciousness
A
- product of biological events occurring within brainstem and thalamus
- derives from the activation of the intralaminar nuclei of the thalamus by the reticular activating system which project from the reticular formation of the brainstem
14
Q
Apnea test procedure
A
- Deliver 100% O2 for 10 minutes.
- pCO2 is around 40 mmHg on ABG.
- Maintain adequate blood pressure (~90) and pulse (>50).
- Determine if pt has tripped the vent recently.
- Disconnect vent from ET tube and begin timing
- Deliver O2 at 6L/min by t-piece, thus oxygen is being delivered.
- Observe and feel for respiratory effort (if breathing is observed, stop test and reconnect ventilator)
- After 8 minutes, draw blood gas and reconnect ventillator.
- **If no respiratory effort was observed and pCO2 is more than 20 mmHg higher than baseline, the apnea test is positive, consistent with brain death.
15
Q
Confirmatory tests for brain death
A
- Cerebral angiogram → 4 vessel, in brain death no flow above neck.
- EEG → flat line almost, not entirely flat b/c of artifacts from vent and moving patient
- Evoked responses → BAER, VER, Somatosensory ER
- Radionucleotide scan → cerebral blood flow
- CT angiogram → contrast media and CT immediately. Most conclusive.
- Transcranial doppler blood flow study → Last choice. Difficult.
