Shock occurs when your blood pressure falls to a very low level. As your blood pressure falls, your brain and other organs don't get enough blood or oxygen to function, and they begin to fail. Shock can arise from any of a number of causes. It is a life-threatening medical emergency and must be treated early to avoid serious complications and even death.

Common signs and symptoms of shock include the following:

• Low blood pressure
• Altered mental state, including reduced alertness and awareness, confusion, and sleepiness
• Cold, moist skin. Hands and feet may be blue or pale
• Weak or rapid pulse
• Rapid breathing and hyperventilation
• Decreased urine output
• In septic shock (from overwhelming blood infection) -- shaking chills, rapid temperature increase, warm, flushed skin, and rapid pulse
• In shock related to heart problems -- lung congestion, rapid pulse, heart murmur, enlarged neck veins

Shock can have several causes. Doctors classify shock according to four categories:

Loss of fluid in the bloodstream (hypovolemic shock) -- occurs after heavy bleeding from an injury or a condition such as bleeding ulcers. Hypovolemic shock can also occur if your body loses too much fluids other than blood (such as losing water after severe diarrhea or vomiting, or losing plasma after serious burns).

Blood vessels become too dilated (distributive shock) -- If the blood vessels expand too much, they are not able to keep blood circulating to all organs. Septic shock, which occurs when bacteria invade the bloodstream, and anaphylactic shock, which is a severe allergic reaction, are examples.

Heart problems (cardiogenic shock) -- In this case, the heart doesn't pump enough blood through the body. It can be caused by a heart attack, abnormal heart rhythm, or damage to the heart from heart disease.

The following conditions and characteristics increase the risk for shock:

• Serious injury and trauma
• Heart conditions such as heart disease or heart attack
• Surgery
• Bacterial infection that has spread to the blood
• Bleeding
• Losing large volume of fluids from severe diarrhea or vomiting
• Excessive alcohol use
• Severe anemia
• Weakened immune system
• Allergic reaction to a drug, food, or environmental exposure
• Drug overdose
• Pregnancy

Shock is an emergency and requires immediate conventional treatment. Your health care provider will diagnose shock based on your symptoms and any information about underlying disease or recent injury. Your health care provider will check blood pressure, assess mental status (memory, orientation, and alertness), measure urine output, and order blood tests to check heart, lung, and kidney function and search for evidence of sepsis (blood infection). Imaging and other procedures -- such as x-ray, electrocardiography (ECG), echocardiography -- may be performed to check the heart.

Prevention

If you have heart disease or another condition that makes you susceptible to shock, you should make sure you are treated for that condition. If you have severe allergies, avoid substances that may trigger anaphylactic shock and carry self-injectable epinephrine to treat anaphylaxis.

Treatment Plan

The main goals of treatment are to maintain blood pressure and to make sure the person's vital organs get enough blood and oxygen. First aid for shock includes having the person lie on their back, raising their legs to help blood return to the heart, stopping any bleeding, covering them with a coat or blanket to ensure warmth, and performing cardiopulmonary resuscitation (CPR), if needed. Emergency medical staff will administer oxygen and, in the case of hypovolemic and septic shock, intravenous fluids.

Drug Therapies

The following medications may be used to treat shock:

• Drugs that increase pressure in the arteries and help the heart pump more blood, such as dopamine, dobutamine, and norepinephrine
• Medications to either dilate or constrict blood vessels (depending on the cause of shock)
• Antibiotics for septic shock, to combat wide-ranging infection
• Thrombolytic therapy (drugs that dissolve clots as they form) may be considered in the case of heart attack or pulmonary embolism

Complementary and Alternative Therapies

Shock is always life-threatening and requires emergency conventional medical care. Some complementary and alternative therapies, however, may be used along with conventional treatment, after a person's condition stabilizes to help prevent shock. For instance, certain nutrients may help protect against the harmful effects of shock and improve the outcome of conventional treatment.

Nutrition and Supplements

Oxidative stress (damage to cells caused by the body's normal use of oxygen) may play a role in shock. Several studies have suggested treatment with antioxidants that help rid the body of free radicals (harmful byproducts of the oxidative process) may protect against some types of shock. However, most of these have been animal studies. It is not known whether or not these supplements will also benefit humans.

• L-carnitine, a substance which occurs naturally in the body's cells, may be helpful in treating cardiogenic, septic, and hypovolemic shock. A study of 115 patients with septic, cardiac, or traumatic shock showed that acetyl-L-carnitine helped return heart rate and blood pressure to normal and boosted oxygen delivery throughout the body.
• Coenzyme Q10, an antioxidant, may be beneficial in treating hypovolemic and septic shock. One study of hemorrhagic (bleeding-related) shock in animals showed that coenzyme Q10 helped protect lung function and improve blood flow. A study on animals with septic shock showed that coenzyme Q10 improved heart function, blood flow, and blood pressure. Another suggested that pretreatment with coenzyme Q10 improved lung function of the animals who later developed septic shock.
• Glutamine added to parenteral nutrition (nutrients given through the veins, or IV) may protect the intestines and prevent complications from septic shock.
• Omega-3 fatty acids -- Animal studies show that omega-3 essential fatty acids, found in fish oil, may fight inflammation and may protect against septic shock.
• Vitamins B₃ -- Animal studies have suggested that nicotinamide (a form of vitamin B₃) may help protect against bacteria that cause septic shock.
• Vitamin B₁₂ -- Animal studies suggest that taking hydroxocobalamin (a form of vitamin B₁₂₎ may improve blood pressure.

Herbs

As noted, shock always requires emergency conventional medical treatment and should never be treated with herbs alone. Some herbs that support the immune system may be beneficial in treating septic shock, along with conventional medications. Talk to your doctor before taking any herbs to treat or prevent shock.

An Ayurvedic formula containing the following herbs helped reduce bacteria levels in the blood of rats infected with Escherichia coli (an infection that can spread to the bloodstream, potentially causing septic shock):

• Ashwagandha (Withania somnifera)
• Indian gooseberry (Phyllanthus emblica)
• Sweet basil (Ocimum sanctum)
• Tamarisk ( Tinospora cordifolia)

Several newly developed herbal remedies based on traditional Chinese medicine were evaluated for use in 183 people with septic shock. Injections of the following herbs appeared to increase blood circulation as well as lower the death rate significantly in the treatment group:

• Kangjue tongmai
• Yiqi huiyang
• Yiqi jiuyin

Two herbs that have been used traditionally to treat shock are aconite (Aconitum napellus), a highly toxic herb that should only be used with a doctor's supervision, and ginseng (Panax ginseng).

Homeopathy

Scientific studies of homeopathic remedies for the treatment of shock specifically have not been conducted. The remedy Aconite, however, is often used by homeopathic doctors for emergency conditions. In homeopathic remedies, aconite is highly diluted, and only a trace amount of the herb is present, so it is not toxic in a homeopathic formulation.

If someone suffering from shock receives immediate treatment, the prognosis is good. Immediate treatment for anaphylactic shock, for example, usually results in complete recovery. But any case of shock is life-threatening, regardless of its cause, particularly in the elderly. Shock often causes organ damage (including the kidneys, brain, and liver), cardiac arrest, and respiratory failure.

If you are suffering from shock, you will likely be admitted to intensive care. Following treatment, your health care provider will carefully monitor your condition, including temperature, blood pressure, cardiac function, urine flow, and blood chemistry.

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