Surgical risk is a form of evaluation of the clinical condition and health conditions of the person who will undergo surgery, so that risks of complications are identified throughout the period before, during and after surgery.
It is calculated through the clinical evaluation of the doctor and the request for some tests, but to facilitate, there are also some protocols that better guide the medical reasoning, such as ASA, Lee and ACP, for example.
Any doctor can do this evaluation, but usually it is done by the general practitioner, cardiologist or anesthesiologist. In this way, it is possible that some particular care is taken for each person before the procedure, such as requesting more appropriate tests or performing treatments to reduce the risk.
How is the preoperative evaluation performed
The medical evaluation done before surgery is very important to better define what type of surgery each person can or can not do, and to determine if the risks are greater than the benefits. The evaluation involves:
1. Performing the clinical examination
The clinical examination is done with the collection of data of the person as medicines in use, symptoms, diseases that have, besides the physical evaluation, such as ausculta cardiac and pulmonary.
From the clinical evaluation, it is possible to obtain the first form of risk classification, created by the American Society of Anesthesiologists, known as ASA:
- ASA 1 : healthy person, without systemic diseases, infections or fever;
- ASA 2 : person with mild systemic disease, such as controlled high blood pressure, controlled diabetes, obesity, age above 80 years;
- ASA 3 : person with severe but not disabling systemic disease, such as compensated heart failure, infarction for more than 6 months, angina pectoris, arrhythmia, cirrhosis, diabetes or decompensated hypertension;
- ASA 4 : person with life-threatening disabling systemic disease, such as severe heart failure, infarct for less than 6 months, insufficiency of the lungs, liver and kidneys;
- ASA 5 : dying person, not expected to survive for more than 24 hours, such as after an accident;
- ASA 6 : person with brain death detected, who will undergo surgery for organ donation.
The higher the number of ASA classification, the greater the risk of mortality and complications from surgery, and it should be carefully assessed which type of surgery may be worthwhile and beneficial to the person.
2. Evaluation of the type of surgery
Understanding the type of surgical procedure that will be done is also very important, because the more complex and time-consuming the surgery, the greater the risks that the person can suffer and the care one should have.
Thus, types of surgery can be classified, according to risk of cardiac complications, such as:
| Low risk | Intermediate Risk | High Risk |
Endoscopic procedures, such as endoscopy, colonoscopy; Superficial surgeries such as skin, breast, eyes. |
Surgery of the thorax, abdomen or prostate; Head or neck surgery; Orthopedic surgeries, such as after fracture; Correction of abdominal aortic aneurysms or removal of carotid thrombi. | Large emergency surgeries. Surgeries of large blood vessels, such as the aorta or carotid, for example. |
3. Evaluation of cardiac risk
There are some algorithms that measure in a more practical way the risk of complications and death in non-cardiac surgery, when investigating the clinical situation of the person and some tests.
Examples of algorithms used are Goldman 's Cardiac Risk Index, Lee's Revised Cardiac Risk Index, and the American College of Cardiology (ACP) Algorithm, for example. To calculate the risk, they consider some of the person's data, such as:
- Age, which is at higher risk than 70 years;
- History of myocardial infarction;
- History of chest pain or angina;
- Presence of arrhythmia or vessel narrowing;
- Low oxygenation of blood;
- Presence of diabetes;
- Presence of heart failure;
- Presence of lung edema;
- Type of surgery.
From the data obtained, it is possible to determine the surgical risk. So if it is low, it is possible to release the surgery, if the surgical risk is medium to high, the doctor can make guidelines, adjust the type of surgery or request more tests that help to better evaluate the surgical risk of the person.
4. Conduct of necessary exams
Preoperative examinations should be done with the aim of investigating any changes, if there is suspicion, that can lead to a surgical complication. Therefore, the same tests should not be requested for all people, since there is no evidence that this helps reduce complications. For example, in people without symptoms, with low surgical risk and who will undergo a low risk surgery, it is not necessary to perform tests.
However, some of the most commonly requested and recommended tests are:
- Hemogram : people who undergo an intermediate or high risk surgery, with a history of anemia, with current suspicion or with diseases that can cause changes in blood cells;
- Coagulation tests : people using anticoagulants, liver insufficiency, history of bleeding diseases, intermediate or high risk surgeries;
- Dosage of creatinine : patients with kidney disease, diabetes, high blood pressure, liver disease, heart failure;
- Chest x-ray : people with diseases such as emphysema, heart disease, age greater than 60 years, people with high cardiac risk, multiple diseases or who will undergo surgery of the chest or abdomen;
- Electrocardiogram : people with suspected cardiovascular disease, history of chest pain and diabetics.
Generally, these tests have a validity of 12 months, with no need for repetition in this period, however, in some cases, the doctor may find it necessary to repeat before. In addition, some doctors may also consider it important to request these tests even for people without suspected changes.
Other tests, such as an exercise test, echocardiogram, or holter, for example, may be ordered for some more complex types of surgery or for people with suspected heart disease.
5. Performing preoperative adjustments
After the tests and exams are done, the doctor can schedule the surgery, if everything is okay, or you can make recommendations so that the risk of surgery complications is minimized.
In that way, he may recommend doing more specific tests, adjusting the dose or introducing medication, assessing the need for correction of heart function through cardiac surgery, for example, guiding some physical activity, losing weight or stopping smoking, among others.
