Shock
In a medical emergency, "shock" does not primarily mean the everyday reaction to bad news, but rather a potentially life-threatening condition that can have various causes. Because shock can be fatal, quick action is essential.
Essentially, shock is the body's emergency response. The body tries to maintain the blood supply to vital organs by reducing blood flow to the periphery-that is, the arms and legs. This is achieved by narrowing the blood vessels in the limbs and is known as centralization. This emergency response is very useful when, for example, there is severe blood loss or a large amount of fluid leaks from the blood vessels into the surrounding tissue. However, metabolic reactions may cause more fluid to leak into the tissue or bleeding to occur in other parts of the body, further reducing the volume of circulating blood. Doctors call this the shock spiral. Once underway, it is very difficult to stop and can lead to complete circulatory collapse with multiple organ failure. This is why early recognition and intervention are so important.
How can I recognize shock?
There are general signs of shock such as
- restlessness, nervousness, anxiety
- paleness
- clammy/sweaty
- feeling cold, possibly shivering
- low blood pressure
- fast pulse that is hard to feel
- rapid breathing
- bluish lips
- later: listlessness, fainting
Depending on the type of shock, the symptoms can vary a bit. Below you will find the different types of shock, how to recognize them, and how you can help the affected person. Not all signs are always present!
What to do if someone is in shock?
There are several general measures that apply to shock. We describe specific first aid measures for certain types of shock in the relevant section. Please note the exceptional situations in which the shock position is not appropriate.
- Stay with the person. Talk to them and reassure them.
- If necessary, stop any bleeding.
- Place them in the shock position (lying flat with their legs raised), unless an exceptional situation applies.
- Keep them warm: Cover the person. A blanket (emergency blanket) may also be placed underneath them.
- Call the emergency services or arrange for someone else to do so.
- Keep checking their consciousness and breathing.
Exceptions where the shock position should not be used
- heart disease, difficulty breathing (see cardiogenic shock)
- head injuries
- spinal injuries
- injuries to the chest or abdomen
- fractures of the pelvis or legs
- severe hypothermia
What types of shock are there?
Shock can have different causes and is therefore divided into
- neurogenic shock (vasovagal syncope as a special form)
- cardiogenic shock
- volume-loss shock (hypovolemic shock)
- allergic shock (anaphylactic shock)
- septic shock
- other types of shock
Neurogenic shock (shock affecting the nervous system)
Neurogenic shock is a disturbance of the central regulation of circulatory function. There is an imbalance between the sympathetic and parasympathetic regulation of heart function and vascular muscle. This causes a generalized widening of the blood vessels throughout the body, leading to a relative volume deficit without any actual loss of volume. Neurogenic shock can occur, for example, as a result of a spinal injury or a traumatic brain injury, and poisoning can also be a cause.
How to recognize it?
- The signs of shock listed above are present, but the skin tends to be warm and sweaty.
- In addition, the circumstances of the accident or discovery provide clues to neurogenic shock.
- There are sensory disturbances or a loss of sensation (paralysis) in the arms and/or legs.
- There are visible head or spinal injuries.
What to do?
- Do not put them in the shock position! Do not change the person's position if they are conscious and breathing.
- If you must change the position because the person is unconscious or not breathing, make sure another helper stabilizes the head.
- Call emergency services as quickly as possible.
- Continuously check their level of consciousness and breathing.
Vasovagal syncope (often called fainting or passing out)
A special form classified as a type of neurogenic shock is known as vasovagal syncope. Syncope is the medical term for a brief loss of consciousness or fainting caused by a temporary reduction in the blood supply to the brain. Vasovagal syncope is an exaggerated vagal response that results in a brief loss of consciousness. The blood vessels temporarily dilate, blood pressure drops, and the return of blood to the heart decreases. The person faints. Now lying flat, blood flows back to the heart and the person regains consciousness. This form can occur after standing for a long time, but also as a result of psychological influences such as shock, fear, pain, emotional stress, joy, and similar triggers. Sometimes even the sight of a few drops of blood is enough. Vasovagal syncope is therefore not a disease, but an exaggerated response that causes no lasting harm as long as the person is not injured when they faint. Nevertheless, it should be confirmed that there are no other causes behind the fainting.
How to recognize it?
Fainting is often preceded by dizziness, nausea and paleness - the person may seem absent.
What to do?
If the person is still standing, lay them down immediately and raise their legs (shock position). Put the person in this position even if they are already unconscious, and ensure that they keep breathing.
Cardiogenic shock (shock related to the heart)
Cardiogenic shock is caused by the heart's inability to pump enough blood. The heart can no longer pump sufficient blood into the circulation. Causes can include a heart attack, pulmonary embolism, myocarditis, a severely enlarged heart, or certain types of arrhythmias.
How to recognize it?
In addition to the general signs of shock, the cardiogenic shock shows these specific features:
On the one hand, the information provided and the person's behavior may indicate a heart problem. They complain of
- - a feeling of tightness and pressure in the chest
- - pain
- - shortness of breath
- - anxiety
- - a slow pulse, possibly irregular
- - possible distended neck veins
What to do?
- Do not put them in the shock position! Sit them up and position them comfortably.
- Call emergency services as quickly as possible or make sure someone does.
- Shield the person from further agitation - keep them calm and quiet.
- Loosen or remove tight clothing.
- Monitor the person continuously for consciousness and breathing.
- If an AED (defibrillator) is available, have it brought. These devices are made for use by laypeople and are very easy to use. Follow the instructions on the device and the voice prompts.
Hypovolemic shock (volume-loss shock)
Hypovolemic shock is caused by a lack of circulating fluid. This can be due to blood loss, either from severe internal bleeding (for example from a torn blood vessel or organ, gastrointestinal bleeding, or a fracture of the pelvis or thigh, and the like) or external bleeding (heavily bleeding wounds), or by loss of water and electrolytes (vomiting, diarrhea, or dehydration) or plasma loss (burns, pleurisy, peritonitis, etc.).
How to recognize it?
- The general signs of shock apply.
- Visible external injuries with blood or plasma loss are present.
- The place where the person was found or the accident situation may indicate internal injuries.
- There may be a fracture of the pelvis or thigh.
What to do?
- Control bleeding
- Place the person in the shock position unless they have a chest or abdominal injury, spinal injury, pelvic or thigh fracture, head injury, or difficulty breathing
- Keep checking consciousness and breathing regularly
Allergic shock (anaphylactic shock)
Allergic shock is the most severe form of an allergic reaction. It can be caused by many allergens such as insect stings, foods, or medications. Anaphylactic shock is currently described as an acute pathological immune reaction to a chemical trigger that affects the whole body. It is divided into four grades.
How to recognize it?
- Grade 1: generalized hives, itching and/or redness, possibly also dizziness, headache and anxiety
- Grade 2: in addition, a fast heartbeat and drop in blood pressure, often nausea and vomiting as well as mild breathing difficulty
- Grade 3: severe breathing difficulty (similar to an asthma attack), a sharp drop in blood pressure, very fast heartbeat; angioedema (formerly Quincke's edema) may occur, causing swelling mainly around the eyelids, chin, cheeks, lips, tongue or genitals; the hands and feet may also become severely swollen; possible involvement of the airways (especially the glottis) is dangerous and can lead to life-threatening breathing difficulty
- Grade 4: respiratory or circulatory arrest
What to do?
- Stop the possible cause.
- Call emergency services as quickly as possible or make sure someone does.
- Calm and continuously monitor the person; keep the situation quiet.
- Shock position
- Keep them warm
- Continuously check consciousness and breathing.
- If the person vomits, help them as needed (do not force vomiting; assist by holding and preventing inhalation of vomit).
Septic shock
Septic shock can occur as a result of blood poisoning (sepsis) or a similar condition, such as systemic inflammatory response syndrome (SIRS), and requires immediate treatment in an intensive care unit. People whose immune systems are weakened or who have increased exposure to pathogens are particularly at risk. Septic shock is confirmed by laboratory tests.
Because septic shock occurs as a result of an existing blood infection (sepsis) and the patient is usually already under medical care, we omit further details here on "How to recognize?" and "What to do?".
Other types of shock
Other types of shock include, for example, endocrine forms caused by hormone deficiency or excess, toxic shock syndrome (TSS), hyperglycemic shock caused by excessively high blood sugar, and hypoglycemic shock, which involves an insufficient supply of glucose but is not a classic form of shock because there is no imbalance between oxygen supply and demand; instead, it is triggered by an insufficient supply of glucose.
Sources:
This article is from Tensana – the leading app since 2011, helping hundreds of thousands of people monitor their blood pressure every day.
Our content is based on carefully researched, evidence-based data and is continuously updated (as of 02/2026).
Author Sabine Croci is a qualified medical assistant with many years of experience in internal medicine and cardiology practices as well as outpatient care, and has headed the specialist editorial team at Tensana since 2015. Thanks to her extensive additional qualifications as an emergency medical technician, first responder, and in various areas of therapy and emergency care, she provides well-founded, practical, and reliably verified information.
Author Sabine Croci is a qualified medical assistant with many years of experience in internal medicine and cardiology practices as well as outpatient care, and has headed the specialist editorial team at Tensana since 2015. Thanks to her extensive additional qualifications as an emergency medical technician, first responder, and in various areas of therapy and emergency care, she provides well-founded, practical, and reliably verified information.
