Do induced hypertension and hypotension affect stroke volume variation in man Journal of Clinical Anesthesia, 05/04/2012

Wajima Z et al. – Stroke volume variation (SVV) does not misinterpret preload dependency assessment of patients receiving medications to increase or to lower blood pressure.

• 31 ASA physical status 1 and 2 patients, aged 39-62years, who were scheduled for elective surgery.
• The authors conducted three studies: a pressor test study, a depressor test study, and an induced hypotensive anesthesia study.
• In the pressor test, patients received a bolus of phenylephrine 0.001mg/kg to increase systolic arterial pressure (SAP) by 30% to 40% compared with baseline.
• In the depressor test, patients received a bolus of nitroglycerine 0.005mg/kg to decrease SAP by 30% to 40% compared with baseline.
• In the induced hypotensive anesthesia test, patients received intravenous (IV) nitroglycerine continuously until mean arterial pressure (MAP) was reduced to 60-70mmHg.
• When arterial pressure reached the target pressure for each study type, SVV and other parameters were recorded.

• Induced hypertension (pressor test) decreased SVV, while induced hypotension (depressor test) and induced hypotensive anesthesia increased SVV.