- Various intravenous (IV) antihypertensives are commonly administered in the operating room and other acute care settings, but their individual effects on cerebral blood flow (CBF) and neurocognition remain unclear.
- In this systematic review and meta-analysis of 50 studies, the authors evaluated the effects of different IV antihypertensive agents on cerebral blood flow in humans.
- Twenty-five studies focused on normotensive subjects without intracranial pathology, 9 focused on hypertensive subjects, and 16 studies focused on patients with intracranial pathology.
- Numerous IV antihypertensive agents were considered in this analysis, with nicardipine, labetatol, nitroprusside, and nitroglycerine, nicardipine most commonly used in the included studies.
- For most of the IV antihypertensives considered in this analysis (including nicardipine) reductions in MAP of 20% did not result in significant changes in CBF, across a wide array of clinical contexts and patient profiles. Moreover, for most antihypertensives the reduction in MAP did not correlate to any reduction in CBF, indicating that CBF autoregulation largely remains intact with IV antihypertensive administration.
- Importantly, however, the administration of either nitroprusside or nitroglycerine was associated with a reduction in CBF. When administered to awake, normotensive patients without intracranial pathology, these agents produced a mean 17% decrease in MAP resulting in a mean 13% decrease in CBF. The authors conclude that these particular antihypertensives have the potential to impact cerebral perfusion even when used at appropriate and typical clinical doses.
- In their discussion, the authors cite historical data demonstrating that acute neurocognitive changes can occur after a decrease in CBF of 38%. These historical data bolster their contention that nitroprusside and nitroglycerine should be administered with caution while taking into account the clinical context.
Summary of "Impact of intravenous antihypertensive therapy on cerebral blood flow and neurocognition: a systematic review and meta-analysis"
Summary published April 14, 2025
