The correlation between the Trendelenburg position and the stroke volume variation / 대한마취과학회지

ABSTRACT

BACKGROUND: The stroke volume variation (SVV), based on lung-heart interaction during mechanical ventilation, is a useful dynamic parameter for fluid responsiveness. However, it is affected by many factors. The aim of this study was to evaluate the effects of SVV on Trendelenburg (T) and reverse Trendelenburg (RT) position and to further elaborate on the patterns of the SVV with position. METHODS: Forty-two patients undergoing elective surgery were enrolled in this study. Fifteen minutes after standardized induction of anesthesia with propofol, fentanyl, and rocuronium with volume controlled ventilation (tidal volume of 8 ml/kg of ideal body weight, inspiration expiration ratio of 1 2, and respiratory rate of 10-13 breaths/min), the patients underwent posture changes as follows supine, T position at slopes of operating table of -5degrees, -10degrees, and -15degrees, and RT position at slopes of operating table of 5degrees, 10degrees, and 15degrees. At each point, SVV, cardiac output (CO), peak airway pressure (PAP), mean blood pressure, and heart rate (HR) were recorded. RESULTS: The SVV was significant decreased with decreased slopes of operating table in T position, and increased with increased slopes of operating table in RT position (P = 0.000). Schematically, it was increased by 1% when the slope of operating table was increased by 5degrees. But, the CO and PAP were significant increased with decreased slopes of operating table in T position, and decreased with increased slopes of operating table in RT position (P = 0.045, 0.027). CONCLUSIONS: SVV is subjected to the posture, and we should take these findings into account on reading SVV for fluid therapy.