Shock, the medical condition related to adequate blood flow, takes many forms and has different patterns of signs and symptoms depending on which type of shock the patient is experiencing.
There are four main categories of shock: hypovolemic, cardiogenic, distributive, and obstructive.1
Each of the different categories has multiple causes, and each of the causes comes with different signs and symptoms.
The most common symptom to all shock—at least eventually—is low blood pressure.2
As untreated shock gets worse, the blood pressure falls. Eventually, the blood pressure falls too low to maintain life (called hemodynamic instability) and shock becomes fatal.
Depending on the cause, it can take a long time or it can be very quick.
While low blood pressure is the only symptom that is present at the end of every shock category, some categories of shock are much more common than others.
That means their symptoms are also more common. Here are the categories of shock in order of frequency, with their common symptoms.
Not having enough fluid or blood volume (hypovolemia), is the most common type of shock.
It can come from bleeding (also known as hemorrhagic shock) or from some other sort of fluid loss and dehydration.
As the body tries to compensate for the loss of blood or fluid and attempts to keep the blood pressure up, these signs occur:2
- Rapid heart rate (rapid pulse)
- Rapid breathing
- Dilated pupils
- Pale, cool skin
- Sweating (diaphoresis)
As hypovolemic shock gets worse, the patient becomes lethargic, confused, and eventually unconscious.
If external bleeding is the cause, there will be blood. If bleeding into the gastric system is the cause, the patient might vomit blood or have bloody diarrhea.
If it’s hot or the patient has been exerting herself, consider dehydration.
This is the hardest category of shock to understand, but it is very common.
When arteries in the body become flaccid and no longer can constrict properly, the blood pressure is very hard to control and will fall.
The two most common causes for this type of shock are severe allergies (anaphylaxis) and severe infections (sepsis).
Symptoms vary depending on the cause.
Anaphylaxis symptoms include:3
- Swelling, particularly of the face
- Trouble breathing
- Skin redness
- Rapid heart rate
Sepsis symptoms include:4
- Fever (not always)
- Flush, red skin
- Dry mouth
- Poor skin elasticity (turgor), which means if you pinch the skin it stays pinched and returns slowly back to normal, if at all.
Sepsis is often a combination of distributive and hypovolemic shock because these patients are commonly dehydrated.
Neurogenic shock (from a broken spinal cord and often called spinal shock) is a rare cause of distributive shock, but has a very distinct pattern of symptoms:5
- Low blood pressure is an early sign (unlike other forms of shock)
- Normal heart rate (can be elevated, but is the type of shock most likely to have a normal rate)
- A “line” on the body where skin is pale above and flushed red below
Neurogenic shock comes on after some sort of trauma, such as a fall or a car accident.
When the heart has difficulty pumping blood adequately, it is known as cardiogenic shock.
It can occur after a myocardial infarction (heart attack), malfunction of a heart valve, cardiac arrhythmias, infections of the heart, and trauma to the heart.1
Symptoms of cardiogenic shock include:
- Weak and often irregular pulse
- Sometimes a very slow pulse
- Difficulty breathing
- Cough producing frothy sputum, white or sometimes pink in color
- Swelling in the feet and ankles
Cardiogenic shock can be accompanied by the signs and symptoms of a heart attack.
Probably the least common main category of shock (neurogenic is the least common specific type), obstructive shock comes from something pressing on the blood vessels inside the body.
The most common cause of obstructive shock is from a tension pneumothorax (collapsed lung).2
- Low blood pressure can happen quickly, but the body will be trying to compensate (unlike neurogenic shock)
- Rapid pulse
- Unequal breath sounds (if caused by a pneumothorax)
- Trouble breathing
Besides a tension pneumothorax, the other most likely cause of obstructive shock is from cardiac tampenade, a rare condition caused by blood trapped in the sack around the heart, pressing on it and keeping it from adequately pumping blood.
When to Go to the Hospital
Shock is a true medical emergency and should be treated as soon as it can be recognized. If you suspect shock, call 911 or your emergency number immediately and get to the hospital.2
As long as the body is managing to keep the blood pressure up, the medical community considers it compensated shock.
When the blood pressure falls—even in cases when that happens early, such as neurogenic shock or obstructive—the medical community refers to it as decompensated shock.
If decompensated shock is left untreated, it has a high likelihood of becoming fatal.
- Standl T, Annecke T, Cascorbi I, Heller AR, Sabashnikov A, Teske W. The nomenclature, definition and distinction of types of shock. Dtsch Arztebl Int. 2018;115(45):757–768. doi:10.3238/arztebl.2018.0757
- Haseer Koya H, Paul M. Shock. StatPearls.
- American Academy of Allergy Asthma and Immunology. Anaphylaxis.
- Centers for Disease Control and Prevention. What is sepsis?
- Summers RL, Baker SD, Sterling SA, Porter JM, Jones AE. Characterization of the spectrum of hemodynamic profiles in trauma patients with acute neurogenic shock. Journal of Critical Care. 2013;28(4):531.e1-531.e5. doi:10.1016/j.jcrc.2013.02.002
- Cecconi M, De Backer D, Antonelli M, et al. Consensus on circulatory shock and hemodynamic monitoring. Task force of the European Society of Intensive Care Medicine. Intensive Care Medicine. 2014;40(12):1795-1815. doi:10.1007/s00134-014-3525-z.
- Kolte D, Khera S, Aronow WS, et al. Trends in incidence, management, and outcomes of cardiogenic shock complicating ST‐elevation myocardial infarction in the United States. Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease. 2014;3(1):e000590. doi:10.1161/JAHA.113.000590.