the r-r intervals of an electrocardiogram , the coefficient variation of r-r intervals ( cv-rr ) , and the power spectrum of heart rate fluctuation were studied just before surgical operations in a group of 10 patients who underwent high thoracic epidural anesthesia ( tea ) , and before anesthesia in a control group of 10 patients who were scheduled for general anesthesia without tea .
C0002903
anesthesia
C0002915
general anesthesia