Approach to diagnosis of coma

1. Coma Dr Ashraf Abdou Professor Neuropsychiatry dept. Alexandria Univ

3. Consciousness Is Dependent on: 1) An Intact Ascending Reticular Activating System (central tegmental fasiculus) AROUSAL 2) Intact Cerebral Cortex AWARNESS

6. The ARAS and Essential Neurotransmitters Locus Coeruleus: Epinephrine Raphe Nucleus: Serotonin Basal Nucleus: Acetylcholine

9. States of Altered Consciousness State Description of Patient Lethargy fatigued with minimal difficulty maintaining alertness Vegetative State recover the arousal component of consciousness but not awareness. Stupor unresponsiveness with arousal only vigorous/painful stimulus, return to unresponsiveness with removal of stimulus

13. Common Etiologies of Coma Approximate mortality Drug Overdose 5-10% Metabolic 50% Head Trauma 50% Anoxia 90% Stroke 80% Status Epilepticus 3-30%

17. Supratentorial Mass Lesions Acute epidural hematoma and midline shift

18. Supratentorial Mass Lesions Cerebral Abscess

34. Practical approach YES YES NO NECK RIGIDITY INFECTION or SAH FOCAL NEUROLOGICAL SIGNS METABOLIC INTRACRANIAL LESION NO

35. Quick approach to etiology Infections SAH Neck Rigidity Intracranial lesion Metabolic or toxic Comatose patient YES No YES NO Focal Signs

44. Pupillary Responses in Various Lesions

45. Oculocephalic and Vestibular Responses

46. Abnormal Breathing Patterns Cheyne-Stokes crescendo/decrescendo pattern mixed with apnea bilateral hemisphere dysfunction Central neurogenic hyperventilation rapid deep breathing lesion between midbrain and pons Apneustic breathing prolonged inspiration followed by apnea pontine dysfunction Ataxic breathing irregular pattern medullary dysfunction-close to death Coma with hyperventilation metabolic derangement Coma with hypoventilation drug overdose COPD

47. Guidelines to Determining Brain Death Prerequisites -proximate cause is known and demonstrably irreversible -metabolic derangements corrected to extent possible -no drug intoxication -core temperature greater than 32C Three Cardinal Findings in Brain Death 1) Coma- no cerebral response to noxious stimuli in all extremities 2) Absence of Brainstem Reflexes- no pupillary response, no oculocephalic response, no oculovestibular response, no corneal reflex, jaw reflex, grimace, gag, or cough 3) Apnea- core temp 36.5, SBP >90, no DI, no tidal volume with PCO2>60mm Hg

49. DECEREBRATE DECORTICATE

50. Cheyne Stokes HV neurógena central Respiraciones apneústicas Normal GCS Motor 6 5 4 3 2 1