Rosen & Barkin's 5-Minute Emergency Medicine Consult (508 page)

• Probably genetic
  
• Family history of panic or anxiety is common
  
• Altered serotonin- and benzodiazepine-receptor function
  

Limbic system, norepinephrine release, other neurotransmitters (e.g., serotonin) implicated, leading to “fight-or-flight” response

• Major life events in the year preceding onset
  
• Family history of panic or anxiety
  
• Childhood shyness or separation anxiety
  
• May develop in the course of predisposing physical illness or cocaine abuse:
  
  • May persist after the illness or substance use has resolved
    
• Twice as common in women
  

DIAGNOSIS

• Multiple systems suggest autonomic arousal
  
• Cardiac:
  
  • Palpitations
    
  • Tachycardia
    
  • Chest pain or discomfort
    
• Respiratory:
  
  • Shortness of breath
    
  • Smothering
    
  • Feeling of choking
    
• Neurologic:
  
  • Tremor
    
  • Dizziness
    
  • Lightheadedness
    
  • Feeling faint
    
  • Numbness
    
  • Tingling
    
  • Sweating
    
  • Chills
    
  • Flushing
    
  • Feelings of unreality or detachment
    
• Gl:
  
  • Nausea
    
  • Cramps
    
  • Abdominal pain
    
• Intense fears:
  
  • Automatic, stereotypic
    
  • Imminent death
    
  • Having a heart attack
    
  • Humiliation
    
  • Loss of control—”going crazy”
    

• Known medical conditions
  
• All medications, including over the counter
  
• Herbal supplements
  
• Recreational drugs/alcohol use
  
• Caffeine consumption
  
• Age at onset
  
• Initiating life events or stressors
  
• Childhood antecedents
  
• Resultant avoidance
  
• Response to previous medication trials
  
• Family history of panic, anxiety
  
• Family history of drugs/alcohol use
  

• Thorough physical and neurologic exam
  
• Guided by particular symptoms
  

Detailed history, appropriate physical exam:

• Guided by presentation and initial findings
  
• May be minimal, depending on presentation
  

• Toxicology screen
  
• Consider tricyclic antidepressant (TCA) level
  
• CBC
  
• Electrolytes, BUN/creatinine, glucose
  
• Thyroid-stimulating hormone
  
• Pulse oximetry or arterial blood gases
  

• ECG for suspected mitral valve prolapse (MVP), to exclude underlying cardiac disease, or to monitor for QRS widening in patients on TCA:
  
  • Age >40 yr
    
  • Cardiac symptoms
    
• Holter monitor:
  
  • If palpitations, near-syncope
    
• Sleep-deprived EEG if seizure suspected
  

• Consider organic causes if:
  
  • Panic presents late in life (>50 yr)
    
  • No childhood antecedents or family history
    
  • No initiating or major life events
    
  • Without avoidance or significant fear
    
  • With a history of poor response to anxiolytic or antidepressant medication
    
• Medications:
  
  • Neuroleptics (akathisia)
    
  • Bronchodilators
    
  • Digitalis
    
  • Anticholinergic agents
    
  • Psychostimulants
    
  • Diet pills
    
  • Herbal supplements
    
• Respiratory:
  
  • Asthma
    
  • Hyperventilation
    
  • Chronic obstructive pulmonary disease
    
  • Pulmonary embolus
    
  • Bacterial pneumonia
    
  • Costochondritis
    
• Cardiovascular:
  
  • Angina
    
  • Myocardial infarction
    
  • Arrhythmia
    
  • Anemia
    
  • MVP
    
• Substances:
  
  • Stimulant abuse
    
  • Withdrawal (alcohol, sedative–hypnotics)
    
  • Antidepressant discontinuation syndrome (with interruption, dose decrease, or discontinuation of SSRI or SNRI)
    
  • Excessive caffeine intake
    
• Endocrine:
  
  • Hyperthyroidism
    
  • Hypoglycemia
    
  • Hypoparathyroidism
    
  • Pheochromocytoma
    
• Other metabolic derangements:
  
  • Hypokalemia
    
  • Hypomagnesemia
    
  • Hypophosphatemia
    
• Neurologic:
  
  • Complex partial or limbic seizures (fear, physical symptoms, perceptual distortions)
    
  • Transient ischemic attack
    
  • Labyrinthitis
    
  • Benign positional vertigo
    
• Psychiatric:
  
  • Obsessive-compulsive disorder
    
  • Post-traumatic stress disorder
    
  • Specific phobia or social phobia
    
  • Somatoform disorder
    
  • Factitious disorder
    
  • Acute grief
    
• Domestic violence
  

Tachycardia

TREATMENT

• If diagnosis is supported by previous events, history and workup:
  
  • Reassurance and diversion
    
  • Does not require emergent care
    
• If 1st episode, treat and transport as appropriate to presentation
  

• Be calm and reassuring.
  
• Most panic attacks resolve within 20–30 min without any treatment.
  
• Fear may trigger another panic attack.
  

• Patient education, new cognitions:
  
  • Normal response to abnormal alarm
    
  • Physiologic explanations for symptoms
    
• High-potency benzodiazepines (
  drugs of choice):
  
  • Clonazepam:
    
    • Slow for emergency use
      
    • Long-acting without rapid onset/offset phenomena
      
    • Best choice in this class for maintenance therapy of recurrent panic attacks
      
  • Alprazolam:
    
    • Rapid onset
      
    • Rebound anxiety occurs due to short duration and rapid offset.
      
    • May lead to escalating doses with continued use
      
  • Lorazepam:
    
    • Quick onset
      
    • Advantage of sublingual (SL) use
      
    • Longer effect and less abrupt offset than alprazolam
      
• Avoid low-potency benzodiazepines:
  
  • Diazepam
    
  • Chlordiazepoxide
    
• Treat recurrent panic attacks and panic disorder with selective serotonin reuptake inhibitors (SSRIs) (or TCAs), with or without clonazepam:
  
  • Will not work immediately
    
  • Do not need to be started emergently, especially if there is no clear, established access to follow-up management
    
• There are a few small studies on the efficacy of atypical antipsychotics (e.g., olanzapine, risperidone) for treatment-resistant panic disorder. However, data to support this use is limited.
  
• Discharge therapy:
  
  • Several clonazepam tablets in case of repeated attacks
    

• Clonazepam: 0.5 mg PO in the ED; 0.25–0.5 mg PO BID for initial outpatient therapy
  
• SSRI:
  
  • To be started as an outpatient
    
  • May require higher doses and longer time to therapeutic response for panic than for depression
    

• Lorazepam: 1 mg PO or SL
  
• TCA:
  
  • To be started as an outpatient
    

• Limit use of benzodiazepines.
  
• Risk/benefit discussion about the relative safety of SSRIs and less anticholinergic TCAs (e.g., nortriptyline, desipramine)
  
• Physiologic and autonomic effects of pregnancy and postpartum period may trigger attacks in predisposed women.
  

FOLLOW-UP

• As medically indicated to rule out organic cause
  
• Meets criteria for psychiatric admission (suicidal, homicidal)
  

Most panic attacks do not require inpatient level of care.

• Managed care mental health carve-outs
  
• Psychopharmacologic and cognitive behavioral therapy evaluation for repeated attacks, or interepisode fear or avoidance
  
• Stigma
  
• Primary care follow-up may be an acceptable alternative to specialty, mental health/psychiatry referral.
  

• Appointment with primary care physician or referral to mental health specialty treatment
  
• Avoid precipitants, e.g., caffeine, stimulants, alcohol.
  

• Panic is “contagious.” Try not to be infected by the patient’s sense of urgency to stop the symptoms; they will resolve spontaneously.
  
• Be calm so as not to add to the patient’s alarm, but diligent, so patient feels attended to and reassured.
  
• Cognitive–behavioral therapy (CBT) can start in the ED with brief explanation of the physiologic cause of symptoms.
  
• Be cautious not to start adolescents and young adults on a lifetime course of benzodiazepines; CBT (±SSRI therapy) is associated with good outcomes and fewer deleterious side effects.
  
• Avoid the use of alprazolam, especially for ongoing treatment.