Drop attack

Drop attacks are sudden spontaneous falls while standing or walking, followed by a very swift recovery, within seconds or minutes.

See also: Atonic seizure

Causes

Drop attacks are typically seen in elderly patients, and the most common cause is carotid sinus hypersensitivity, resulting in either short periods of reversible asystole, or in marked drop in blood pressure in response to carotid sinus stimulation.

Other causes include the following:

1. vascular - transient ischemic attack, cerebrovascular accident, dissection, occlusion, hemorrhage
   • intracranial hematoma
   • posterior circulation infarction, emboli, vasospasm
   • bilateral anterior circulation occlusion
   • migraine accompagnee - develop over 1hr with assoc paresthesia, HA
   • basilar artery insuff - older pt with no LOC, transient loss of LE tone
2. epilepsy/paroxysmal
   • neurally mediated syncope - 75% of all causes
   • Atonic seizure
   • Lennox-Gastaut syndrome - atonic, myoclonic, GTC typically in neuro abnormal pt
   • Juvenile Myoclonic Epilepsy - fall with myoclonus
   • cataplexy associated with narcolepsy
   • periodic paralyses
   • complex partial seizure
   • breath holding spells - associate pallor/cyanosis, emotional aspect
   • pure autonomic failure (Riley Day, long standing DM)
   • episodic ataxia
   • Panayiotopoulos syndrome
3. degenerative
   • postural instability with Parkinsons
4. structural
   • chronic odontoid instability
   • spinal cord trauma with transient paraplegia
   • brainstem mass
5. metabolic
   • hypoglycemia, hypocalcemia, Hypomagnesemia
   • toxins, drugs - cocaine, sedatives, antihistamine, TCA
6. cardiac
   • prolonged QT, tachycardia, bradycardia, sick sinus syndrome, arrhythmia, IHSS. AS
   • hypovolemia
7. psychiatric
   • malingering, conversion, panic, anxiety
8. labirynth idropsy: an overflow of endolymph in ear labirynth causes distortions and breaks; see also Ménière's syndrome

Diagnosis

• important if there was an inciting event (NMS, breatholding, postural), any LOC, and presence of postictal pd
• initially get glucose, EKG, pregnancy test, Utox, CT head, lytes
• later consider EEG, echocardiogram, MRI, tilt test