Pre-Op Testing
Pre-Op Evaluation
The purpose of the preoperative evaluation is to determine if you are healthy enough to undergo an operation.
Numerous organs are involved in the stress response that occurs from surgical procedures, and for this reason, multiple tests are often completed prior to surgery.
It’s important to collect information about the function of your heart, lungs, liver, and kidneys. If not, you may need to have some medical “tuning up” prior to your surgery.
Pre-Op evaluation often includes the following:
- Pre-Op Worksheet
- Anesthesia Evaluation
- Blood Work
- Chest X-Ray
- Urine Testing
- Electrocardiograms
- Prior Medical Conditions
Pre-Op Worksheet
Our Pre-Op Worksheet is provided at the time of your evaluation. This worksheet gives your physician all of the information he or she requires to give you the best care possible. Most of the questions are self-explanatory.
Anesthesia Evaluation
Unless you are scheduled for a minor surgical procedure not requiring anesthesia or sedation, you will be under the care of more than one physician while in surgery.
Anesthesiologists and nurse anesthetists, their partners in anesthesia care, play an essential role in the success of your operation. Many advances in surgical technique have followed advances in anesthesia care; as such, the anesthesia you receive is as important as the procedure you undergo.
Prior to surgery, a professional from your anesthesiologist’s department will assess your medical condition and anesthetic risk. The questions they ask will be largely identical to the ones asked by your surgeon. Although it’s easy to become frustrated when asked the same questions repeatedly, rest assured that the redundancy built into the system is for your own benefit.
Blood Work
Expect to have your blood drawn on more than one occasion while preparing for surgery. Beyond the tests completed to diagnose your condition, you will be given numerous tests to assess the function of your vital organs. Blood will be drawn to determine the number of oxygen-carrying red blood cells (RBCs) and infection-fighting white blood cells (WBCs) you have, as well as the number of platelets.
Unusual values in these numbers may require a postponement of your surgery until it can be determined why you have abnormal results. In most healthy people, these tests comes back normal.
The next test is called a coagulation profile, sometimes referred to as a PT and PTT. This test is designed to determine if your blood clots in the normal fashion. As you can imagine, performing surgery on a patient whose blood doesn’t clot normally can be quite a challenge.
Medications can be administered to temporarily correct abnormal blood clotting; however, if you are scheduled for elective surgery and you have a disorder of coagulation, your surgeon will want to know where the problem lies and to the problem can be corrected prior to your operation.
At a minimum, you will also have blood drawn to determine your kidney (also called renal) function. These tests measure the amount of protein breakdown products circulating in your blood, namely blood urea nitrogen (BUN) and creatinine; again, it is important to have normal kidney function prior to surgery. If your test shows abnormalities in this regard, you will probably be asked to see a nephrologist (kidney doctor) prior to surgery.
Most of this testing will be done prior to your arrival at the hospital, so that the results are available before you enter the operating room. If you are having minor surgery, these tests may not be performed.
When you arrive at Edgewood, expect to have more blood drawn. This is sometimes done in conjunction with the placement of an intravenous (IV) catheter, but sometimes you will require more than one “stick” or needle insertion to accomplish this. The blood drawn on your admission is typically used to perform a type and crossmatch in the event that you require a blood transfusion. These tests can not be done earlier because the blood samples used for this are only good for a few days.
Chest X-Ray
The preoperative chest x-ray (CXR) is not done on all patients, but it is routine for patients over the age of 50 or patients who have a history of smoking/lung disease. If you fall into one of these categories and you have not had a CXR in more than three months, you will probably need to have one prior to surgery. Your surgeon is looking for a number of things, including the presence of an infection, the indication of lung disease, or the presence of a lung mass. Additionally, chest x-rays let physicians look at the size of your heart and whether any fluid is accumulating in your lungs (a condition known as congestive heart failure). Abnormalities on the chest x-ray may mandate a trip to a pulmonologist (lung specialist) or cardiologist (heart specialist) prior to elective surgery.
Smokers or patients with known lung disease need additional testing prior to surgery. If your CXR is abnormal or if you are going to have a lung resection, your surgeon may want you to have pulmonary function tests (PFTs). This series of tests determine how well you move fresh air in and out of your lungs. It also allows your surgeon to tell how well you absorb the oxygen that you inspire.
Patients who have a mass in their lung will need a chest CT (or cat scan), which provides high resolution images that aid your surgeon in determining which procedure to perform. Occasionally, an MRI will also be performed in the preoperative period.
Finally, your doctor may order an arterial blood gas (ABG) prior to surgery. This test requires that a needle be inserted into one of your arteries (usually in your wrist or groin), and determines the amount of oxygen and carbon dioxide in your blood. It also determines the pH (or acidity) of your blood. This information is important in determining whether you are able to withstand an operation, and is also necessary for your postoperative care.
Urine Testing
Along with the blood drawn at your preoperative visit, most physicians also ask that you submit a urine sample. Urine samples are useful for testing a number of things, as many of your body’s metabolites are removed in the urine. A urinalysis (or UA) can indicate your state of nutrition, your level of hydration (or dehydration), the presence of diabetes, or the presence of an infection.
If your UA shows that you have a urinary tract infection (an abnormal amount of bacteria in your urine), your doctor will prescribe antibiotics prior to surgery, because wound infections are more common in patients who have an underlying infection at the time of surgery.
For those going to the hospital to have a fistula or graft placed for dialysis access or a kidney transplant, you will have already had many more extensive tests performed to determine the function of your kidneys.
Electrocardiograms (EKG/ECG)
Obtaining an EKG prior to surgery is an important part of the preoperative work-up.
An EKG can not predict what will happen to your heart in the future, but the EKG can look at the electrical activity generated by your heart. As a result, the pattern of the heart’s electrical activity can tell your doctor if you have ever had a heart attack in the past (which you may not even have known about).
In response to stress, your heart not only beats faster, but it also beats more forcefully. If you have a normal heart, this is no problem, but if your heart has a poor blood supply (as seen in patients with coronary artery disease), this added work can cause serious problems.
An EKG also shows if your heart is in a normal rhythm, how well the conduction system of the heart works, and if any of the chambers of the heart are working too hard (a condition call hypertrophy). An abnormal EKG will usually trigger a series of other tests, including echocardiography and stress testing.