When Would You Need Them?

Vasopressors are medications that can increase blood pressure in emergency situations.

For certain conditions, these hormones are injected into a large vein using a central venous catheter (central line) in critical care settings (e.g., emergency departments and intensive care units).

This article delves into how vasopressors work, when they are taken, safety considerations, and more.

When Are Vasopressors Taken?

Typical scenarios in which healthcare providers may administer vasopressors include severe infections (like sepsis) or in critical care settings for conditions like shock.

Sepsis is a life-threatening organ failure that occurs when the body doesn’t respond properly to an infection. It can result from pneumonia or infections of the skin, gastrointestinal tract, or urinary tract.

Sepsis is a significant cause of death in intensive care units (ICUs). Vasopressors are given for sepsis if blood pressure remains low after healthcare providers have administered IV fluids.

Shock is a circulatory problem caused when organs or tissues don’t get enough blood. It’s the main reason people are admitted to the ICU.

There are different types of shock, including the following:

• Vasodilatory shock, which includes septic shock and anaphylactic shock. This is the most common type of shock. It causes the skin to become warm, so it’s also termed “warm shock.” Vasopressors are typically injected after healthcare providers have administered fluids.
• Cardiogenic shock, typically caused by a heart attack. Norepinephrine is the vasopressor most often used in this scenario.
• Hemorrhagic shock, which is caused by massive blood loss. Using vasopressors for this type of shock is controversial and isn’t routinely recommended.

How Do Vasopressors Work?

Vasopressors activate (turning on) receptors in the heart and blood vessels. When these receptors turn on, the body’s “fight or flight response” (the sympathetic nervous system) also activates.

Vasopressors function in the body to constrict (narrow) blood vessels. When blood vessels constrict, blood pressure increases, and more blood is released into the body. The blood then delivers oxygen and other necessary nutrients to vital organs so they can continue to function.

Types of Vasopressors

Some vasopressors (epinephrine, norepinephrine, and dopamine) are made in the body. These are called endogenous catecholamines (hormones made in the body that transmit chemical messages).

Other vasopressors, like phenylephrine, are exogenous catecholamines—they’re not made in the body.

Vasopressors available in the United States include: 

• Norepinephrine (Levophed), the first choice medicine for all types of shock that are associated with very low blood pressure. Norepinephrine doesn’t affect the heart rate like many other vasopressors do.
• Epinephrine (also called adrenaline), typically a second choice after norepinephrine. It is recommended for people with refractory shock, which can happen when the body doesn’t respond to fluids and high doses of epinephrine. It’s also a good choice after heart surgery because it helps heart function.
• Vasopressin, another possible second choice that is sometimes added to epinephrine. It’s also known as antidiuretic hormone (ADH).
• Phenylephrine, commonly used to reverse low blood pressure caused by general anesthesia.
• Dopamine, typically only used for people with low heart rates (bradycardia). It’s not used routinely due to side effects like abnormal heart rhythms.
• Angiotensin II (brand name Giapreza), an option for people with septic shock or those with severely low blood pressure.

Possible Side Effects

Vasopressors are associated with severe side effects, such as heart attacks and blood loss to parts of the body (ischemia). For this reason, they are used only when necessary, usually at low doses and for a short period.

Healthcare providers give these medicines in healthcare settings and will closely monitor you if you receive them. They’ll watch for common side effects such as:

Some potential side effects you might notice include: 

• Changes in heart rate, including increased heart rate (tachycardia) or decreased heart rate (bradycardia).
• Changes in skin color of fingers and toes. Blue or purple discoloration can occur with vasopressor treatment. This is a warning sign that blood flow to the hands and feet is blocked (ischemia). Ischemia is dangerous because it can lead to the death of tissues in these body parts (necrosis). If not addressed quickly, fingers or toes may have to be amputated (cut off). Keep in mind that changes in skin color are typically less pronounced in people with darker skin, so ischemia and necrosis may be harder to spot.
• Changes in temperature of fingers and toes. These can turn colder with vasopressor treatment.
• Breathing problems.

Be sure to inform your healthcare provider immediately if you or someone you are caring for experience any of these side effects while being treated with vasopressors.

Safety Considerations

Several important safety concerns are associated with vasopressor infusions. Here are some key points to keep in mind.

Some people should not use vasopressors. These include people who are allergic to components of these medicines.

Vasopressors can interact with other medications. Some notable interactions include, but are not limited to:

Healthcare providers and pharmacists will make decisions about your hospital treatment plan based on your current medication regimen. If you or a loved one cannot provide them with an up-to-date medicine list, a healthcare provider can typically consult your electronic medical record instead. 

Summary

Vasopressors are medications that are given by injection for medical emergencies like shock and sepsis.

They work by increasing blood pressure and circulating blood throughout the body.

Vasopressors can save lives, but they come with serious safety concerns. Fortunately, when you need vasopressors, healthcare providers will closely monitor you for potentially serious side effects. These include abnormal heart rate or rhythm and circulation problems in your fingers or toes.