Dismiss Modal

Diagnosis

Tests Done Before Surgery

Choose a preferred language

Many surgeons order routine lab tests before you are admitted to the hospital or before certain outpatient procedures. The tests help find possible problems that might complicate surgery if not found and treated early. Some of the most common tests done before surgery include:

  • Chest X-rays. X-rays can help diagnose causes of shortness of breath, chest pain, cough, and certain fevers. They can also help diagnose heart and lung problems.

  • Electrocardiogram (ECG). This test records the electrical activity of the heart. It shows abnormal rhythms (arrhythmias); finds heart muscle damage; and helps find the cause of chest pain, fluttering heartbeats (palpitations), and heart murmurs.

  • Urinalysis. This test can help diagnose kidney and bladder infections and diabetes. Certain types of urinalyses can also find illegal drugs in the body.

  • White blood count. This test can help diagnose certain fevers and infections. It can also find out if you're using medicines that affect white blood counts.

  • Pregnancy testing. This test can help find out if you're pregnant. Pregnancy changes the way surgical patients are managed. So knowing this information helps keep you and your baby safe.

You may also need one or more of these blood tests before surgery:

  • Glucose. This test measures your blood sugar levels.

  • Electrolytes. This test measures the amount of potassium, sodium, and other electrolytes in your blood. These chemicals help regulate heart rhythms and other body functions.

  • Renal function studies. This test measures blood urea nitrogen (BUN) and creatinine to see how well the kidneys are functioning.

  • Complete blood count (CBC). This test checks for a low number of red blood cells (anemia), a low platelet count, and infection.

  • Coagulation studies (PT/PTT). These tests find out how well your blood clots.

Talk with your health care provider if you have questions or concerns about any of the tests you're taking.

Featured in

© 2000-2025 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.

Find a doctor that's right for you.

From routine check-ups to groundbreaking treatments and beyond, Crestner Health is here to help you live your healthiest life.

Search our doctors
Related Articles
Read article
Surgery
Post-Surgery Checklist

After surgery, there are steps you can take to help with your recovery. You may have been an inpatient (staying in the hospital overnight) or an outpatient (going home the day of surgery). While in the hospital, it is important to follow directions from your surgeon, nurse, and other health care providers.

Read article
Surgery
Checklist for Surgery/Consent Forms/Insurance Information

The decision to have surgery is an important one. Here is a checklist to help you prepare. You'll need to arrange a time for any preoperative lab tests and for an interview with the anesthesiologist. Check with your health plan regarding costs and coverage of the surgery.

Read article
Surgery
Wound Check After Surgery, No Complication

If your wound was sewn closed, you shouldn't have to change the dressing more than twice a day in the first few days. Follow these home care instructions after your wound check.

Read article
Surgery
Surgery for Appendicitis

A helpful guide to understanding surgery for appendicitis.