What is the severity of surgical risk?

From the Guidelines

Surgical risk severity can be classified into three main categories: low risk (less than 1% cardiac risk), intermediate risk (1% to 5% cardiac risk), and high risk (more than 5% cardiac risk), with the specific risk depending on the type of surgery and patient factors. The classification of surgical risk is crucial in determining the need for further evaluation and management of patients undergoing noncardiac surgery. According to the ACC/AHA guidelines 1, the risk of major cardiac complications, such as myocardial infarction or cardiac arrest, can be estimated using tools like the Revised Cardiac Risk Index (RCRI) or the American College of Surgeons NSQIP Surgical Risk Calculator. These tools take into account various patient-specific factors, including age, sex, body mass index, dyspnea, previous myocardial infarction, and functional status, as well as the type of surgery being performed. Some examples of low-risk surgeries include endoscopic procedures, superficial procedures, and cataract surgery, while intermediate-risk surgeries include carotid endarterectomy, head and neck surgery, and orthopedic surgery 1. High-risk surgeries, such as vascular surgery, are associated with a higher risk of cardiac complications and may require more extensive evaluation and management. The American College of Surgeons NSQIP Surgical Risk Calculator is a useful tool for estimating surgery-specific risk of major cardiac complications and death. It is essential to note that the risk of surgical complications can be minimized by following preoperative instructions, disclosing all medications and supplements, maintaining good nutrition, stopping smoking, and discussing any concerns with the healthcare provider. Understanding these risk factors and using available tools to estimate surgical risk can help healthcare providers make informed decisions and reduce the risk of complications. Key factors to consider when assessing surgical risk include the type of surgery, patient age, overall health status, existing medical conditions, and medication use, as these can all impact the risk of cardiac complications and other adverse outcomes 1.

From the FDA Drug Label

5 WARNINGS AND PRECAUTIONS

1. 3 Seizures Tranexamic acid may cause seizures, including focal and generalized seizures. The most common setting for tranexamic acid-induced seizures has been during cardiovascular surgery (a setting in which tranexamic acid is not FDA-approved and which uses doses of up to 10-fold higher than the recommended human dose and in patients inadvertently given tranexamic acid into the neuraxial system)

The severity of surgical risk is not directly stated in the drug label. However, it can be inferred that cardiovascular surgery may be a high-risk setting for seizures when using tranexamic acid, especially at high doses.

• Key points:
  • Tranexamic acid may cause seizures during surgery
  • Cardiovascular surgery is a setting where seizures have occurred
  • High doses of tranexamic acid may increase the risk of seizures 2

From the Research

Severity of Surgical Risk

The severity of surgical risk can be significant, particularly for patients undergoing major vascular surgery or other high-risk procedures. Several studies have highlighted the importance of preoperative risk stratification to identify patients at increased risk of perioperative complications.

• Patients with comorbidities such as coronary artery disease, heart failure, left-sided valvular heart disease, and significant arrhythmic burden are at higher risk of perioperative major adverse cardiovascular events (MACE) 3.
• The use of beta-blockers, statins, and aspirin has been shown to reduce the risk of perioperative MACE in high-risk patients undergoing major vascular surgery 4.
• Advance care planning (ACP) is also crucial for high-risk patients undergoing elective surgery, as it allows for preparation for potential perioperative complications and improves outcomes 5.

Risk Factors for Postoperative Complications

Several risk factors have been identified as predictors of postoperative complications, including:

• Hypertension, carotid disease, diabetes, and age, which are associated with an increased risk of postoperative stroke 6.
• Preoperative comorbidities and risk factors, which can be used to classify patients into latent risk classes using latent class analysis (LCA) 7.
• The combination of statin and beta-blocker therapy, which has been shown to confer a protective effect for stroke after coronary artery bypass graft (CABG) surgery 6.

Stratification of Surgical Risk

The stratification of surgical risk can be achieved through various methods, including:

• The use of cardiac risk indices, such as the Revised Cardiac Risk Index (RCRI), to predict the risk of perioperative MACE 3, 4.
• LCA, which can be used to classify patients into latent risk classes based on preoperative risk factors 7.
• The identification of high-risk patients who may benefit from ACP and other interventions to reduce the risk of perioperative complications 5.