From the Guidelines
I would generally avoid giving a beta blocker prior to cardiac surgery to a patient on an intra-aortic balloon pump (IABP). Beta blockers like metoprolol, atenolol, or carvedilol are typically contraindicated in patients requiring mechanical circulatory support from an IABP. This is because patients on IABP already have compromised cardiac function and are dependent on the balloon pump for hemodynamic stability. Beta blockers reduce heart rate, contractility, and blood pressure, which could further compromise cardiac output and potentially lead to hemodynamic collapse in these already vulnerable patients. The IABP works by augmenting diastolic pressure and reducing afterload, requiring a certain level of native cardiac function to be effective.
Key Considerations
- The decision to continue or hold beta blockers in patients on chronic therapy should be made on a case-by-case basis in consultation with the cardiac surgical team and anesthesiologists, carefully weighing the risks of withdrawal against the risks of continued administration 1.
- In some specific situations where tachyarrhythmias are present despite IABP support, very cautious use of short-acting beta blockers like esmolol might be considered under close hemodynamic monitoring, but this would be the exception rather than the rule.
- The 2014 ACC/AHA guideline on perioperative cardiovascular evaluation and management of patients undergoing noncardiac surgery recommends continuing beta blockers in patients who are on beta blockers chronically 1.
- However, the guideline also states that beta-blocker therapy should not be started on the day of surgery, which implies that initiating beta blockers in patients on IABP support may not be beneficial and could potentially be harmful 1.
Clinical Implications
- The use of beta blockers in patients on IABP support requires careful consideration of the potential risks and benefits, and should be individualized based on the patient's specific clinical circumstances.
- The cardiac surgical team and anesthesiologists should work together to determine the best course of action for each patient, taking into account factors such as the patient's underlying cardiac function, the presence of tachyarrhythmias, and the potential risks of beta blocker therapy.
- Close hemodynamic monitoring is essential in patients on IABP support who are receiving beta blockers, in order to quickly identify and respond to any potential adverse effects.
From the FDA Drug Label
Chronically administered beta-blocking therapy should not be routinely withdrawn prior to major surgery; however, the impaired ability of the heart to respond to reflex adrenergic stimuli may augment the risks of general anesthesia and surgical procedures
The patient is on an Intra-Aortic Balloon Pump (IABP), which indicates severe cardiac dysfunction. Administering a beta blocker prior to cardiac surgery in this scenario may increase the risk of cardiac complications.
- The benefits of continuing beta blocker therapy in patients with coronary artery disease undergoing major surgery should be weighed against the potential risks of impaired cardiac response to anesthesia and surgery.
- Given the patient's critical condition, caution is advised when considering the administration of a beta blocker prior to cardiac surgery 2.
From the Research
Administration of Beta Blockers Prior to Cardiac Surgery with IABP
- The use of beta blockers prior to cardiac surgery in patients with an Intra-Aortic Balloon Pump (IABP) is not directly addressed in the provided studies 3, 4, 5, 6, 7.
- However, the studies discuss the use of IABP in high-risk patients undergoing cardiac surgery, including coronary artery bypass grafting (CABG) 4, 5, 6, 7.
- The evidence suggests that preoperative IABP use may have a beneficial effect on mortality and morbidity in specific high-risk patient groups undergoing CABG 5, 6, 7.
- The studies also highlight the importance of careful patient selection and management when using IABP prior to cardiac surgery 3, 4, 6, 7.
Key Findings
- A meta-analysis of 9,212 patients found that preoperative IABP use decreased the risk of morbidity and mortality in high-risk patients undergoing CABG 5.
- Another study found that preoperative IABP use was associated with a significant reduction in hospital mortality and 30-day mortality compared to no preoperative IABP 7.
- However, the evidence is not robust enough to extend the use of IABP to truly elective, high-risk patients, and further research is needed to define which patient groups may benefit from preoperative IABP use 6, 7.