LOSS OF CONSCIOUSNESS • If concern for syncope: EKG to assess for cardiogenic cause • If concern for seizure: EEG and MRI (or CT) to assess for epileptogenic lesion and likelihood of recurrence Consciousness = alertness (appearing awake) + awareness Syncope Seizure (meaningful interaction with the environment) Preceding Lightheadedness, tunnel Aura LOC is attributed to damage of the ascending reticular activating symptoms vision, nausea system (RAS): brainstem reticular nuclei → projections to bilateral Tonic phase Absent Present thalami → projections to bilateral cortices Clonic Can be present Present phase TRANSIENT LOSS OF CONSCIOUSNESS (LOC) Return to Rapid Gradual, +post-ictal baseline confusion Differential diagnosis: syncope, seizure, psychogenic spell *Psychogenic spells are complex, involuntary, and variable in presentation – they usually cannot be diagnosed with a single Key features of the history: episode! • Onset: “What is the last thing you remember before the event?” NON-TRANSIENT LOC o Context/triggers of LOC episode o Preceding symptoms Differential diagnosis: • Duration of LOC • Drugs, drugs, drugs: polypharmacy, drugs of abuse, • Abnormal tonic-clonic movements withdrawal o Tonic phase (bilateral stiffness, ictal cry, eyes open, • VITAMIN C (vascular, infectious, traumatic, autoimmune, jaw clamping) more specific for seizure metabolic, idiopathic/iatrogenic, neoplastic, congenital) o Clonic jerking can be seen in both syncope and seizure • Offset: “What is the first thing you remember after waking Altered states of consciousness: up?” Clouding Minimally reduced wakefulness or awareness o Pace of return to baseline Delirium Fluctuating alertness and awareness o Decreased arousability, confusion, and noisy Obtundation Mild/moderate reduction in alertness and awareness stertorous breathing are more specific for a seizure Stupor Unresponsiveness arousable to vigorous stimulation Coma Unresponsiveness without arousability Examination: • Neurologic examination is frequently normal! Key features of the history (obtained from surrogates): • Findings that suggest tonic-clonic seizure: persistent focal • Time course (i.e., sudden versus gradual) neurologic deficit, vertebral compression fracture (mid-back • Preceding signs/symptoms that may suggest localization tenderness), lateral tongue biting, posterior shoulder • Medication reconciliation dislocation, petechiae of the face/chest/sclera Examination of the unconscious patient: Workup: • Glasgow Coma Scale scoring • Assess for common causes of provoked seizures (e.g., o Eye opening: spontaneous (4); to speech (3); to pain hypoglycemia, electrolyte abnormalities, drug (2); no response (1) intoxication/withdrawal) o Verbal response: oriented (5); confused (4); inappropriate words (3); incomprehensible sounds (2); no response (1) o Motor response: follows commands (6); localizes to pain (5); withdrawal (4); flexor (3); extensor (2); no response (1) • Brainstem reflexes o Pupillary light reflex: Afferent = CN II, Efferent = CN III o Oculocephalic reflex: Afferent = CN VIII, Efferent = CN III, VI o Gag reflex: Afferent = CN IX, Efferent = CN X .