Why a blood test before and after your surgery is crucial

Blood tests are taken before surgery to examine your health condition, and determine signs of infection or the functioning of a specific organ. To make sure that you are ready for the test, certain checkups and tests are taken for surgeries such as before a colonoscopy procedure (a test to examine your colon and large intestine), chemotherapy process (radiation therapy for cancer) or laparoscopic appendectomy (a surgical process to remove your appendix).

You may be asked repetitive questions by doctors of the surgery team before the surgery. This is done to get as much information as possible before they perform surgery on you. The questions may be specific to the type of surgery that is to be performed on you. You need to remain patient throughout the process and answer all their queries correctly.

Common blood tests carried out before and after a general surgery include the following:

1. The Complete Blood Count Test (CBC):

It is a common test performed before and after a surgery. By measuring the count of each type of blood cells present in your blood, the doctor determines if your blood is normal. It also reveals any presence of infections, conditions of dehydration or anemia, or the need for a transfusion after your surgery etc. CBC is especially important before a chemotherapy process since chemotherapy drugs can hamper the production process of your RBCs (red blood cells), WBC (white blood cells) and platelets.

2. Blood Chemistry Tests:

​​​​​​​Blood chemistry tests are perfoparmed before a general surgery to examine if you suffer from any other health conditions. This test is also known as a Chem 7 test because the test looks for 7 different substances found in your blood. Chem 7 test is routinely performed after a surgery takes place.

3. Liver enzyme and function blood tests:

​​​​​​​It is a common test performed before a surgery to check whether your liver is functioning properly or is affected by a disease or infection. A liver biopsy may be required if the result of your tests indicate signs of complications. In some cases, these tests may be performed routinely if you take medications that are known to affect your liver. Liver tests are of the following two types-
Aspartate Phosphatase test (AST) - This is a test used to detect a chronic liver problem or other liver injuries you may be suffering from.
Alanine Aminotransferase Test (ALT) - This test is used to detect long-term injuries in your liver. High levels may indicate conditions of hepatitis from causes like drugs you take, toxins present in your liver, excess alcohol consumption or the presence of a virus in your liver.

4. Coagulation Study:

​​​​​​​Before a general surgery, your doctor may test your blood to find out how fast your blood clots. A group of tests are carried out to determine your coagulation rate. Some surgeries may require slow coagulation of blood, and in such cases, medication may be provided to slow down your clotting process. These tests include-

• PT (Prothrombin Time) - The test is performed before surgery to determine whether you are likely to experience clotting or bleeding problems during or after the surgery.
• PTT (Partial Thromboplastin Time) - This test is performed to check whether blood-thinning therapy (heparin) is effective. It is also used to check if you suffer from a clotting disorder.
• INR (International Normalized Ratio) - This test is taken to ensure that the PT value is the same for one laboratory as it is in another one that you have taken.

For further knowledge about tests and checkups to be performed before or after any other surgery, you may consult a doctor.

He may also help you to make an assessment of the expenses of the tests and choose the best ones for you.