Does intravenous atropine affect stroke volume variation in man?
Zen'ichiro Wajima1, Toshiya Shiga2, Kazuyuki Imanaga3
1Department of Anesthesiology, International University of Health and Welfare Shioya Hospital, Tochigi 329-2145, Japan; Department of Anesthesiology, International University of Health and Welfare Hospital, Tochigi 329-2763, Japan.
Objectives:
Currently there are no reports of the effect of increasing heart rate (HR) induced by intravenous atropine on stroke volume variation (SVV). We hypothesized that increasing HR alters the value of SVV. This prospective study aimed to investigate changes in SVV values by increasing HR induced by intravenous atropine in patients with good cardiac function. We also re-evaluated the effect of intravenous atropine alone on hemodynamics including new hemodynamic parameters such as SVV.
Methods:
Patients were chosen as participants of this study if, 30 minutes after anesthesia induction, HR was below 65 beats/min. Baseline hemodynamic values were recorded, and then the patients received intravenous atropine (0.01 mg/kg; max 0.5 mg). These values were recorded again after intravenous atropine every minute for 5 minutes.
Results:
Ten American Society of Anesthesiologists (ASA) physical status I-II patients aged 37-65 years who were scheduled for elective surgery were included. Intravenous atropine significantly increased HR at the 1-5 minute time points, mean arterial pressure at the 1-4 minute time points, and cardiac output at the 1-3 minute time points compared with baseline values but did not significantly change SVV, stroke volume index, pressure of end-tidal CO2, and systemic vascular resistance.
Conclusion:
Administration of intravenous atropine did not change SVV, and we present this as a novel finding.
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