Post by Admin on Aug 17, 2023 22:00:51 GMT
Shock (circulatory)
en.wikipedia.org/wiki/Shock_%28circulatory%29
Shock is the state of insufficient blood flow to the tissues of the body as a result of problems with the circulatory system.[1][2] Initial symptoms of shock may include weakness, fast heart rate, fast breathing, sweating, anxiety, and increased thirst.[1] This may be followed by confusion, unconsciousness, or cardiac arrest, as complications worsen.[1]
Shock is divided into four main types based on the underlying cause: low volume, cardiogenic, obstructive, and distributive shock.[2] Low volume shock, also known as hypovolemic shock, may be from bleeding, diarrhea, or vomiting.[1] Cardiogenic shock may be due to a heart attack or cardiac contusion.[1] Obstructive shock may be due to cardiac tamponade or a tension pneumothorax.[1] Distributive shock may be due to sepsis, anaphylaxis, injury to the upper spinal cord, or certain overdoses.[1][4]
The diagnosis is generally based on a combination of symptoms, physical examination, and laboratory tests.[2] A decreased pulse pressure (systolic blood pressure minus diastolic blood pressure) or a fast heart rate raises concerns.[1] The heart rate divided by systolic blood pressure, known as the shock index (SI), of greater than 0.8 supports the diagnosis more than low blood pressure or a fast heart rate in isolation.[5][6]
Treatment of shock is based on the likely underlying cause.[2] An open airway and sufficient breathing should be established.[2] Any ongoing bleeding should be stopped, which may require surgery or embolization.[2] Intravenous fluid, such as Ringer's lactate or packed red blood cells, is often given.[2] Efforts to maintain a normal body temperature are also important.[2] Vasopressors may be useful in certain cases.[2] Shock is both common and has a high risk of death.[3] In the United States about 1.2 million people present to the emergency room each year with shock and their risk of death is between 20 and 50%.[3]
Signs and symptoms
The presentation of shock is variable, with some people having only minimal symptoms such as confusion and weakness.[7] While the general signs for all types of shock are low blood pressure, decreased urine output, and confusion, these may not always be present.[7] While a fast heart rate is common, those on β-blockers, those who are athletic, and in 30% of cases of those with shock due to intra abdominal bleeding, heart rate may be normal or slow.[8] Specific subtypes of shock may have additional symptoms.
Dry mucous membrane, reduced skin turgor, prolonged capillary refill time, weak peripheral pulses, and cold extremities can be early signs of shock.[9]
Low volume
Main articles: Hypovolemia and Hypovolemic shock
Hypovolemic shock is the most common type of shock and is caused by insufficient circulating volume.[7] The most common cause of hypovolemic shock is hemorrhage (internal or external); however, vomiting and diarrhea are more common causes in children.[10] Other causes include burns, as well as excess urine loss due to diabetic ketoacidosis and diabetes insipidus.[10]
en.wikipedia.org/wiki/Shock_%28circulatory%29
Shock is the state of insufficient blood flow to the tissues of the body as a result of problems with the circulatory system.[1][2] Initial symptoms of shock may include weakness, fast heart rate, fast breathing, sweating, anxiety, and increased thirst.[1] This may be followed by confusion, unconsciousness, or cardiac arrest, as complications worsen.[1]
Shock is divided into four main types based on the underlying cause: low volume, cardiogenic, obstructive, and distributive shock.[2] Low volume shock, also known as hypovolemic shock, may be from bleeding, diarrhea, or vomiting.[1] Cardiogenic shock may be due to a heart attack or cardiac contusion.[1] Obstructive shock may be due to cardiac tamponade or a tension pneumothorax.[1] Distributive shock may be due to sepsis, anaphylaxis, injury to the upper spinal cord, or certain overdoses.[1][4]
The diagnosis is generally based on a combination of symptoms, physical examination, and laboratory tests.[2] A decreased pulse pressure (systolic blood pressure minus diastolic blood pressure) or a fast heart rate raises concerns.[1] The heart rate divided by systolic blood pressure, known as the shock index (SI), of greater than 0.8 supports the diagnosis more than low blood pressure or a fast heart rate in isolation.[5][6]
Treatment of shock is based on the likely underlying cause.[2] An open airway and sufficient breathing should be established.[2] Any ongoing bleeding should be stopped, which may require surgery or embolization.[2] Intravenous fluid, such as Ringer's lactate or packed red blood cells, is often given.[2] Efforts to maintain a normal body temperature are also important.[2] Vasopressors may be useful in certain cases.[2] Shock is both common and has a high risk of death.[3] In the United States about 1.2 million people present to the emergency room each year with shock and their risk of death is between 20 and 50%.[3]
Signs and symptoms
The presentation of shock is variable, with some people having only minimal symptoms such as confusion and weakness.[7] While the general signs for all types of shock are low blood pressure, decreased urine output, and confusion, these may not always be present.[7] While a fast heart rate is common, those on β-blockers, those who are athletic, and in 30% of cases of those with shock due to intra abdominal bleeding, heart rate may be normal or slow.[8] Specific subtypes of shock may have additional symptoms.
Dry mucous membrane, reduced skin turgor, prolonged capillary refill time, weak peripheral pulses, and cold extremities can be early signs of shock.[9]
Low volume
Main articles: Hypovolemia and Hypovolemic shock
Hypovolemic shock is the most common type of shock and is caused by insufficient circulating volume.[7] The most common cause of hypovolemic shock is hemorrhage (internal or external); however, vomiting and diarrhea are more common causes in children.[10] Other causes include burns, as well as excess urine loss due to diabetic ketoacidosis and diabetes insipidus.[10]