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Last reviewed: 14 Mar 2025
Last updated: 20 Aug 2024

Summary

Definition

History and exam

Key diagnostic factors

  • hypotension
  • tachycardia
  • skin changes
  • oliguria
  • mental state changes
  • presence of risk factors
  • fever
  • chest pain
  • dyspnoea
  • hypoxaemia
  • hypothermia

Other diagnostic factors

  • abdominal pain
  • peripheral oedema
  • raised jugular venous pressure (JVP)
  • muffled or quiet heart sounds
  • arrhythmia
  • petechial rash
  • urticarial rash
  • angio-oedema
  • reduced breath sounds on one side of the chest
  • tracheal deviation
  • distended bladder
  • flaccid paralysis of the limbs

Risk factors

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

Diagnostic investigations

1st investigations to order

  • lactate (from arterial blood gas)
  • venous blood gas (VBG) or arterial blood gas (ABG)
  • glucose
  • full blood count
  • urea and electrolytes
  • coagulation studies
  • C-reactive protein
  • procalcitonin
  • ECG

Investigations to consider

  • chest x-ray
  • urinalysis and urine pregnancy test
  • infection screen
  • point-of-care ultrasound
  • CT chest, abdomen, and pelvis
  • computed tomographic pulmonary angiography (CTPA)
  • x-ray long bones
  • x-ray spine

Treatment algorithm

Contributors

Expert advisers

Alexander Alexiou, MBBS, BSc, DCH, FRCEM, Dip IMC RCSEd

Emergency Medicine Consultant

Barts Health NHS Trust

Physician Response Unit Consultant

London’s Air Ambulance

Royal London Hospital

UK

Disclosures

AA declares that he has no competing interests.

Clovis Rau, MBBS, BSc, FRCEM DipIMC

ST6 Emergency Medicine

Barnet Hospital

Royal Free NHS Foundation Trust

UK

Disclosures

CR declares that he has no competing interests.

Acknowledgements

BMJ Best Practice would like to gratefully acknowledge the previous expert contributor, whose work has been retained in parts of the content:

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

Paul Frost

Reader (clinical)

Centre for Medical Education

School of Medicine

Cardiff University

Honorary Consultant in Intensive Care Medicine

University Hospital of Wales

Cardiff

UK

Disclosures

PF declares that he has no competing interests.

Michael Toolis, MBBS, FCICM, GDipClinUS

Consultant Intensivist

Monash Health

Melbourne

Australia

Disclosures

MT declares that he has no competing interests.

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