Shock is commonly diagnosed when signs of hypoperfusion are associated with low or declining blood pressure.
Shock may result from a number of disease processes, including pump failure (cardiogenic), loss of intravascular volume (hypovolemic), failure of vasoregulation (distributive), or obstruction to blood flow (obstructive).
Initial treatment aims to optimize oxygen delivery and reverse hypoperfusion through volume resuscitation, vasoactive agents for refractory hypotension due to vasodilation, management of cardiac dysfunction, and treatment of the underlying cause.
Management of shock is best undertaken in a critical care environment.
Shock is most commonly defined as the life-threatening failure of adequate oxygen delivery to the tissues and may be due to decreased blood perfusion of tissues, inadequate blood oxygen saturation, or increased oxygen demand from the tissues that results in decreased end-organ oxygenation and dysfunction. If left untreated, shock results in sustained multiple organ dysfunction, and damage to vital organs with possible death. Tissue hypoperfusion may be present without systemic hypotension, but at the bedside shock is commonly diagnosed when both are present (arterial hypotension and organ dysfunction).
History and exam
Key diagnostic factors
- altered cognition/agitation
Other diagnostic factors
- prolonged capillary refill time
- muscle weakness
- cool extremities
- evidence of trauma
- petechial rash
- chest pain
- 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
- increasing age
- myocardial infarction
- heart valve disease
- gastrointestinal bleeding
- ruptured abdominal aortic aneurysm
- burns/heat stroke
- gastrointestinal losses: diarrhea and vomiting
- spinal or brainstem injury
- endocrine disease
- pulmonary embolism
- cardiac tamponade
- new medication (anaphylactic shock)
1st investigations to order
- lactate (arterial blood gas)
- blood gases
- BUN and creatinine
- serum electrolytes
- coagulation studies (INR, activated PTT)
- blood glucose
- anion gap
Investigations to consider
- chest x-ray
- focused assessment with sonography for trauma scan
- 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
Samuel J. Stratton, MD, MPH
Fielding School of Public Health
David Geffen School of Medicine at UCLA
Deputy Health Officer
Orange County Health Care Agency
Health Disaster Management/Emergency Medical Services
SJS declares that he has no competing interests.
Dr Samuel J. Stratton wishes to gratefully acknowledge Dr Christoph Pechlaner and Dr Christian Wiedermann, previous contributors to this topic.
CP and CW declare that they have no competing interests.
Patrick Nee, FRCP, FRCS, FCEM
Consultant in Accident & Emergency Medicine
St Helens & Knowsley Hospitals NHS Trust
PN declares that he has no competing interests.
James Brown, MD, MMM
Vice-Chair and Program Director
Wright State University Department of Emergency Medicine
JB declares that he has no competing interests.
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