From: Differences in heart rate variability may be related to the appearance of postoperative pain in patients undergoing breast cancer surgery
Group A
Group B
p value
HF
41.3 ± 19.8
44.6 ± 14.6
0.621
LF/HF
2.6 ± 2.8
1.5 ± 1.2
0.603
NRS at 2 h admission to PACU
1 ± 0.9
0.5 ± 1
0.292