Steep Trendelenburg position during robotic sacrocolpopexy and heart rate variability.

OBJECTIVES

The objective of this study was to evaluate heart rate variability and hemodynamic parameters following steep Trendelenburg positioning during robotic sacrocolpopexy.

STUDY DESIGN

For 19 women, median age 57 (range: 45-72), blood pressure and ECG were recorded during surgery. From the ECG signals interbeat intervals were used to assess heart rate variability, analyzed in time and frequency domains using the Fast Fourier transform. The low frequency and high frequency spectral bands were used to assess sympathetic and parasympathetic pathways respectively.

RESULTS

All women underwent robotic supracervical hysterectomy and sacrocolpopexy. A statistically significant decrease in the mean values of the low-frequency and high-frequency spectral bands, representing sympathetic and parasympathetic activity, respectively were demonstrated 5min following Trendelenburg positioning of the patients (from 3.6±1.4 to 2.9±0.8ms(2)/Hz, and from 3.5±1.4 to 2.9±1ms(2)/Hz, P<0.05). These changes correlated with a mean 20% decrease in heart rate, which lasted for 30min, and with a second drop in sympathetic and parasympathetic activity and heart rate, commencing 2h from the start of surgery, and lasting until the end of the operation.

CONCLUSIONS

Steep Tredelenburg positioning during robotic urogynecology surgery results in significant changes in the autonomic nervous system modulation of heart rate variability and in other hemodynamic parameters.