What is a common cause of intraoperative hypotension and the first-line treatment?

What is a common cause of intraoperative hypotension and the first-line treatment?

• A. Hypertensive crisis due to excessive vasopressors
• B. Anaphylaxis from antibiotic exposure
• C. Hypovolemia from blood loss; treat with intravenous fluids and vasopressors such as phenylephrine or norepinephrine
• D. Myocardial infarction

Answer: (C)

Hypovolemia from blood loss during surgery reduces venous return and cardiac output, making it a common cause of intraoperative hypotension. The first-line response is to restore circulating volume with intravenous fluids to improve preload. If blood pressure remains low after adequate fluid resuscitation, vasopressors such as phenylephrine or norepinephrine are used to increase systemic vascular resistance and raise mean arterial pressure. It’s important to emphasize fluids first because vasopressors without sufficient preload can worsen perfusion. While other factors like anaphylaxis or myocardial ischemia can cause low blood pressure, hypovolemia due to blood loss is the typical, most frequent scenario in the intraoperative setting, and the standard initial approach reflects that.

Hypovolemia from blood loss during surgery reduces venous return and cardiac output, making it a common cause of intraoperative hypotension. The first-line response is to restore circulating volume with intravenous fluids to improve preload. If blood pressure remains low after adequate fluid resuscitation, vasopressors such as phenylephrine or norepinephrine are used to increase systemic vascular resistance and raise mean arterial pressure. It’s important to emphasize fluids first because vasopressors without sufficient preload can worsen perfusion. While other factors like anaphylaxis or myocardial ischemia can cause low blood pressure, hypovolemia due to blood loss is the typical, most frequent scenario in the intraoperative setting, and the standard initial approach reflects that.