What is the most likely psychiatric diagnosis for a patient who developed acute palpitations after a physical fight, with no prior psychiatric history, medical comorbidities, or substance use?

Acute Stress Disorder

The most likely psychiatric diagnosis for a patient who develops acute palpitations immediately after a physical fight is Acute Stress Disorder (ASD), provided the symptoms include anxiety, intense fear, and occur within four weeks of the traumatic event. 1

Diagnostic Criteria and Clinical Features

Acute stress disorder occurs within four weeks of a traumatic event and is characterized by:

• Anxiety and intense fear or helplessness as core features 1
• Dissociative symptoms that may accompany the presentation 1
• Reexperiencing the traumatic event through intrusive thoughts or memories 1
• Avoidance behaviors related to reminders of the trauma 1
• Physical symptoms including palpitations, which represent autonomic arousal in response to the acute stressor 1

The temporal relationship is critical: symptoms must arise within 3 months of the stressor according to DSM-IV criteria, though onset within 1 month is specified in ICD-10. 2 In this case, the immediate onset of palpitations following the fight fits the acute timeframe perfectly.

Distinguishing from Other Diagnoses

Ruling Out Medical Causes First

Before confirming a psychiatric diagnosis, the emergency physician must establish medical stability through focused assessment rather than routine extensive testing:

• Verify normal vital signs (heart rate, blood pressure, temperature, respiratory rate) as abnormalities suggest organic causes requiring workup 3
• Perform targeted history and physical examination focusing on cardiac symptoms, as palpitations could indicate arrhythmia, particularly if they occurred during the physical exertion of fighting 4
• History and physical examination have 94% sensitivity for identifying medical causes and should focus on any medication use, substance use, or pre-existing cardiac conditions 5

Differentiating from Panic Disorder

The key distinction lies in the presence of an identifiable traumatic trigger (the physical fight):

• Panic disorder requires unexpected panic attacks that are not consistently linked to specific situational triggers 4
• In this case, the palpitations are directly temporally related to the traumatic event (the fight), making them expected rather than unexpected 4
• The patient would not meet panic disorder criteria if all attacks are attributed to trauma-related stimuli 4

Differentiating from Adjustment Disorder

While adjustment disorder with anxiety (ADA) also involves stress-related symptoms:

• Adjustment disorder typically involves less severe stressors such as work problems, divorce, or life transitions 6, 2
• A physical fight constitutes a traumatic event rather than a typical life stressor 1
• ADA symptoms are generally less acute and develop over days to weeks, not immediately 2
• The presence of intense fear during a physically threatening situation points more toward acute stress disorder 1

Clinical Assessment Algorithm

Step 1: Establish temporal correlation

• Document the precise timeline: palpitations began during or immediately after the fight 5
• Confirm the patient experienced intense fear or helplessness during the event 1

Step 2: Rule out cardiac causes

• Check vital signs and perform cardiac-focused physical examination 3
• Consider ECG if palpitations persist or patient has cardiac risk factors 4
• Assess for arrhythmia, particularly if palpitations occurred during physical exertion 4

Step 3: Assess for ASD features

• Evaluate for dissociative symptoms (feeling detached, derealization) 1
• Ask about intrusive thoughts or images of the fight 1
• Assess for avoidance of reminders of the event 1
• Document anxiety symptoms and autonomic arousal 1

Step 4: Screen for substance use

• Determine if alcohol or drugs were involved, as intoxication can complicate assessment 4
• Cognitive abilities rather than specific blood alcohol level should guide whether psychiatric assessment can proceed 4

Risk Stratification and Prognosis

Patients with acute stress disorder are at significantly increased risk of developing PTSD, making early identification crucial 1. Additional risk factors that increase PTSD likelihood include:

• Current or family history of anxiety or mood disorders 1
• History of prior trauma, sexual abuse, or physical abuse 1
• Greater symptom severity one to two weeks after the trauma 1
• Engaging in excessive safety behaviors 1

Treatment Approach

Cognitive behavioral therapy is the most effective intervention for reducing symptoms and decreasing future incidence of PTSD 1. Initial management should include:

• Psychological first aid: ensuring safety, providing information about stress reactions, offering practical assistance, and connecting with social support 1
• Avoid Critical Incident Stress Debriefing, as this method may actually impede natural recovery by overwhelming victims 1
• Pharmacotherapy is not routinely recommended for acute stress disorder, as there is insufficient evidence supporting routine drug use 1
• Short-term symptomatic treatment may be beneficial for specific symptoms like insomnia, but not as primary treatment 1

Common Pitfalls to Avoid

• Do not diagnose panic disorder when all panic attacks are clearly triggered by trauma-related stimuli or reminders 4
• Do not overlook cardiac evaluation in patients with palpitations, especially if they occurred during physical exertion 4
• Do not assume psychiatric diagnosis without first ruling out medical causes through focused assessment 5
• Do not prescribe antidepressants routinely, as there is no robust evidence demonstrating benefits in acute stress disorder 6, 1
• Do not use Critical Incident Stress Debriefing, despite its intuitive appeal, as it may worsen outcomes 1