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Last reviewed: 15 Mar 2025
Last updated: 25 Feb 2025

Summary

Definition

History and exam

Key diagnostic factors

  • altered cognition/agitation
  • hypotension

Other diagnostic factors

  • tachypnea
  • tachycardia
  • prolonged capillary refill time
  • oliguria
  • muscle weakness
  • cyanosis
  • cool extremities
  • evidence of trauma
  • petechial rash
  • chest pain
  • fever
  • abdominal pain
  • jugular venous distention
  • peripheral edema
  • absent breath sounds on one side of chest
  • tracheal deviation
  • quiet heart sounds
  • flaccid paralysis of lower limbs
  • cardiac murmur
  • distended bladder
  • facial and tongue swelling
  • urticarial rash
  • pelvic pain/vaginal bleeding in woman of childbearing age

Risk factors

  • increasing age
  • comorbidities
  • myocardial infarction
  • cardiomyopathy
  • heart valve disease
  • arrhythmias
  • trauma
  • gastrointestinal bleeding
  • ruptured abdominal aortic aneurysm
  • burns/heat stroke
  • gastrointestinal losses: diarrhea and vomiting
  • pancreatitis
  • sepsis
  • anaphylaxis/poisoning
  • spinal or brainstem injury
  • endocrine disease
  • pulmonary embolism
  • cardiac tamponade
  • new medication (anaphylactic shock)

Diagnostic tests

1st tests to order

  • lactate (arterial blood gas)
  • blood gases
  • CBC
  • BUN and creatinine
  • serum electrolytes
  • coagulation studies (INR, activated PTT)
  • blood glucose
  • anion gap
  • CRP
  • ECG

Tests to consider

  • chest x-ray
  • focused assessment with sonography for trauma scan
  • echocardiography
  • procalcitonin
  • end tidal carbon-dioxide (capnography)
  • ultrasound of thorax
  • ultrasound of abdomen
  • CT thorax, abdomen, and pelvis
  • computed tomographic pulmonary angiography
  • urinalysis and urine pregnancy test
  • pelvic ultrasound
  • x-ray long bones
  • x-ray spine

Treatment algorithm

Contributors

Expert advisers

Samuel J. Stratton, MD, MPH

Professor

Fielding School of Public Health

David Geffen School of Medicine at UCLA

Los Angeles

Deputy Health Officer

Orange County Health Care Agency

Health Disaster Management/Emergency Medical Services

Santa Ana

CA

Disclosures

SJS declares that he has no competing interests.

Peer reviewers

Patrick Nee, FRCP, FRCS, FCEM

Consultant in Accident & Emergency Medicine

St Helens & Knowsley Hospitals NHS Trust

Whiston Hospital

Prescot

UK

Disclosures

PN declares that he has no competing interests.

James Brown, MD, MMM

Vice-Chair and Program Director

Wright State University Department of Emergency Medicine

Dayton

OH

Disclosures

JB declares that he has no competing interests.

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