What is the usual mean arterial pressure during cardiopulmonary bypass (CPB) in a patient undergoing heart surgery?

From the Guidelines

During heart surgery with cardiopulmonary bypass, the usual target mean arterial pressure (MAP) should be maintained between 50-80 mmHg, as recommended by the 2024 eacts/eactaic/ebcp guidelines on cardiopulmonary bypass in adult cardiac surgery 1. This pressure range is considered adequate to maintain perfusion to vital organs during bypass. The exact target may be adjusted based on the patient's baseline blood pressure, comorbidities, and specific surgical requirements.

• Key factors to consider when determining the target MAP include:
  • Baseline blood pressure
  • Comorbidities, particularly cerebrovascular disease or chronic hypertension
  • Specific surgical requirements
• The anesthesia team manages MAP through various interventions, including:
  • Adjusting pump flow rates
  • Administering vasopressors, such as phenylephrine, norepinephrine, or vasopressin
  • Administering vasodilators, such as nitroglycerin or sodium nitroprusside, as needed The use of vasopressors to increase the MAP to values above 80 mmHg during CPB is not recommended, according to the guidelines 1.
• Targeting the MAP during CPB within the limits of individualized cerebral autoregulation data, measured under normocapnic conditions before CPB, should be considered whenever the technical and human skills are available, as suggested by the guidelines 1. It is essential to note that the management of MAP during cardiopulmonary bypass requires careful consideration of individual patient factors and close monitoring to ensure optimal perfusion of vital organs.

From the Research

Mean Arterial Pressure During Cardiopulmonary Bypass

• The usual mean arterial pressure during cardiopulmonary bypass is not explicitly stated in the provided studies, but the target ranges can be inferred from the research.
• A study published in 2018 2 compared a higher target (70-80 mmHg) with a lower target (40-50 mmHg) for mean arterial pressure during cardiopulmonary bypass, suggesting that both ranges are used in clinical practice.
• Another study from 2014 3 aimed to maintain mean arterial pressure above 60 mmHg using norepinephrine or phenylephrine, indicating that a minimum threshold of 60 mmHg is considered important.
• A 2022 study 4 defined a higher blood pressure target as a mean arterial pressure of 65 mmHg or greater, and a lower target as less than 65 mmHg, implying that 65 mmHg is a relevant threshold for mean arterial pressure during cardiopulmonary bypass.

Target Ranges for Mean Arterial Pressure

• Higher target range: 65 mmHg or greater 4, 70-80 mmHg 2
• Lower target range: less than 65 mmHg 4, 40-50 mmHg 2
• Minimum threshold: above 60 mmHg 3

Clinical Implications

• The choice of target range for mean arterial pressure during cardiopulmonary bypass may depend on various factors, including patient characteristics and the specific surgical procedure.
• Further research is needed to determine the optimal target range for mean arterial pressure during cardiopulmonary bypass, as the current evidence does not provide a clear consensus 4, 2.