One of the most common side effects of a surgical procedure is infection. In order to lower the number of infections that occur after surgery, it is important for physicians to know how medications used during surgery affect the way the body fights infection. Often, when anesthesiologists are helping people go to sleep before surgery they give people medications known as "volatile anesthetics". Volatile anesthetics are medications that can change from a liquid or solid to a gas very easily. Some studies suggest that these types of medications may change the way white blood cells work in the body. Changing the way white blood cells work could possibly increase the person's risk of infection after their surgery or weaken their body's ability to fight infections. The goal of this research study is to learn about how volatile anesthesia medications change the way white blood cells work in people having anesthesia for cardiac procedures. To do this, investigators will examine the function of while blood cells in the laboratory based setting.

Inclusion Criteria:

• Male and female patients
• greater than or equal to 12 months of age
• scheduled for a cardiac catheterization, cardiac surgery, or cardiac MRI

Exclusion Criteria:

• known underlying hematological disorder
• known oncological disorder
• patients who do not require preoperative laboratory testing

Male and female patients greater than or equal to 12 months of age, who present for a cardiac catheterization, cardiac surgery, or cardiac MRI at Boston Children's Hospital.