If you’re a fan of medical dramas, you’ve probably heard at least one TV doctor pronounce “She’s in shock!” If you’re not someone with a medical background or firsthand experience, this sounds like saying the character is surprised or is experiencing some other serious emotional response to a major situation.
In a medical context, shock isn’t just surprise. It’s a specific diagnosis, often associated with low blood pressure (hypotension, to give it its proper name) and an overly fast heart rate along with symptoms like an altered mental state. That means you don’t just wait for the patient to calm down again. You have to treat the underlying cause.
Shock can actually be divided into four main types, with similar but not identical symptoms. The most common is hypovolemic shock. This is most often caused by major blood loss (a hemorrhage), such as when someone’s been shot or stabbed, but it can also be associated with vomiting, diarrhea, burns and serious diabetic incidents.
It’s not surprising that losing a lot of blood all at once affects your blood pressure, but it’s not as simple as regular hypotension. Your diastolic pressure (the second number in a blood pressure measurement) will actually go up first, before systolic (the first number) goes down. You treat hypovolemic shock by replacing the blood or other lost fluids. If you don’t, it can be fatal.
Cardiogenic shock is commonly linked to low blood pressure. It’s the result of the heart not working properly, such as during a heart attack or when suffering from heart disease. Other symptoms include cold legs and arms and shortness of breath. The different possible causes mean different treatments may be necessary.
You may also experience low blood pressure with obstructive shock, when the blood vessels around the heart are blocked in a physical way. It may involve what’s known as a pulmonary embolism or other complicated-sounding conditions like tension pneumothorax or cardiac tamponade. It can appear similar to cardiogenic shock, but you need to remove the blockage instead of fixing the heart.
The fourth kind is distributive shock. Low blood pressure is the main symptom because this kind of shock involves the blood vessels being dilated. It has further subtypes known as septic shock (caused by infection), anaphylactic shock (caused by allergies) and neurogenic shock (caused by spinal injuries). All types of shock are dangerous.