Last reviewed: February 2018
Last updated: November  2017



History and exam

Key diagnostic factors

  • altered cognition/agitation
  • hypotension

Other diagnostic factors

  • tachypnea
  • chest pain
  • tachycardia
  • slow capillary refill
  • cyanosis
  • cool extremities
  • oliguria
  • evidence of trauma
  • petechial rash
  • abdominal pain
  • jugular venous distention (JVD)
  • peripheral edema
  • absent breath sounds on one side of chest
  • tracheal deviation
  • hiss of air with cannula decompression
  • quiet heart sounds
  • flaccid paralysis of lower limbs
  • cardiac murmur
  • distended bladder
  • facial and tongue swelling
  • urticarial rash
  • fever
  • 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/heatstroke
  • gastrointestinal losses: diarrhea and vomiting
  • pancreatitis
  • sepsis
  • anaphylaxis/poisoning
  • spinal or brainstem injury
  • endocrine disease
  • pulmonary embolism
  • new medication (anaphylaxis)

Diagnostic investigations

1st investigations to order

  • lactate (arterial blood gas)
  • pH (arterial blood gas)
  • partial pressure of oxygen (arterial blood gas)
  • base deficit (arterial blood gas)
  • CBC
  • BUN and creatinine
  • blood glucose
  • serum electrolytes with calculated anion gap
  • C-reactive protein (CRP)
  • procalcitonin (PCT)
  • ECG
  • hiss of air test: decompression of a tension pneumothorax with a cannula
Full details

Investigations to consider

  • chest x-ray
  • focused abdominal sonography exam in trauma (FAST) scan
  • echocardiography
  • ultrasound of thorax
  • ultrasound of abdomen
  • CT thorax, abdomen, and pelvis
  • central venous pressure and venous oxygen saturations
  • urine pregnancy test
  • pelvic ultrasound
Full details

Treatment algorithm



Authors VIEW ALL

Samuel J. Stratton


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



SJS declares that he has no competing interests.

Dr Samuel J. Stratton would like to gratefully acknowledge Dr Christoph Pechlaner and Dr Christian Wiedermann, previous contributors to this monograph. CP and CW declare that they have no competing interests.

Peer reviewers VIEW ALL

Consultant in Accident & Emergency Medicine

St Helens & Knowsley Hospitals NHS Trust

Whiston Hospital




PN declares that he has no competing interests.

Vice-Chair and Program Director

Wright State University Department of Emergency Medicine




JB declares that he has no competing interests.

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