Effect of Aprotinin on Blood Pressure
Aprotinin has minimal direct effects on blood pressure in normotensive individuals but may increase blood pressure in patients with pathological systemic vasodilation such as septic shock or hepatic cirrhosis by reversing vasodilation and increasing systemic vascular resistance.
Mechanism and Effects on Blood Pressure
Aprotinin is a serine protease inhibitor derived from bovine lung tissue that inhibits kallikrein and plasmin, primarily used as an antifibrinolytic agent in cardiac surgery to reduce bleeding 1, 2
In normotensive individuals, aprotinin administration has not been shown to cause significant changes in mean arterial pressure, carotid artery blood flow, or vascular resistance in experimental studies 3
Unlike oral decongestants (such as pseudoephedrine) which can significantly elevate blood pressure through α-adrenergic vasoconstriction, aprotinin does not have direct vasoconstrictive properties in normal physiological states 1, 3
Clinical Scenarios Where Aprotinin May Affect Blood Pressure
In pathological states with systemic vasodilation (such as septic shock or hepatic cirrhosis with ascites), aprotinin can increase systemic vascular resistance and maintain or elevate arterial pressure 4
When given in sepsis, aprotinin has been shown to:
- Maintain arterial pressure and systemic vascular resistance that would otherwise fall
- Block increases in pulmonary artery pressure
- Suppress plasma renin activity 4
In patients with hepatic cirrhosis, aprotinin can:
- Increase systemic vascular resistance in those with low baseline values
- Improve glomerular filtration rate and renal plasma flow
- Suppress plasma renin activity 4
Safety Considerations Related to Blood Pressure
Aprotinin was withdrawn from the European market in 2008 due to safety concerns but was reintroduced in 2012 with narrow licensing indications, specifically for isolated coronary artery bypass graft surgery in high-risk patients 1
While aprotinin does not appear to increase the risk of myocardial infarction or cerebrovascular events, it has been associated with an increased risk of postoperative renal dysfunction [OR 2.03 (1.37-3.01)] 5
Unlike some antifibrinolytic agents like tranexamic acid, which has been extensively studied and found to have no increased risk of thromboembolic complications, the safety profile of aprotinin remains more controversial 1
Clinical Applications
Aprotinin is primarily used in cardiac surgery as an antifibrinolytic agent to minimize bleeding, particularly in high-risk patients 1
In clinical practice, its use often extends beyond its license to include patients likely to bleed during major cardiac surgery such as:
- Acute aortic dissection
- Surgery in patients with infective endocarditis 1
Observational data suggests aprotinin is associated with lower incidence of massive bleeding and reduced mortality in high-risk cardiac surgery, but not in low to moderate-risk patients 1
Monitoring Recommendations
When using aprotinin, particularly in patients with pre-existing hypertension or renal dysfunction, careful monitoring of blood pressure and renal function is warranted 5
Unlike oral decongestants which require blood pressure monitoring in hypertensive patients due to their direct vasoconstrictive effects, aprotinin requires monitoring primarily due to its potential effects on renal function rather than direct blood pressure effects 1, 5