Anesthesia Knowledge Test 1 (AKT-1) Practice

Refractory hypotension refers to persistent low blood pressure that does not respond to standard treatments. One potential cause for this condition in preoperative patients is the use of ACE inhibitors. These medications work by inhibiting the angiotensin-converting enzyme, which ultimately reduces the formation of angiotensin II, a potent vasoconstrictor. This effect can lead to vasodilation and decreased blood volume, resulting in hypotension, especially during the perioperative period when fluid shifts and other stressors may already be compromising hemodynamics.

ACE inhibitors can also impair the body's ability to compensate for low blood pressure, particularly in the setting of acute physiological stress or blood volume changes. As a result, patients taking these medications may exhibit refractory hypotension if not properly managed or if they experience significant perioperative fluid loss.

While hypovolemia, severe systemic diseases, or inappropriate medication use can also contribute to hypotension, ACE inhibitors directly affect the physiological mechanisms responsible for blood pressure regulation, making them a notable and specifically influential contributor to refractory hypotension in this context.