Application value of dexmedetomidine in anesthesia for elderly patients undergoing radical colon cancer surgery

Table 4 Comparison of bispectral index and regional cerebral oxygen saturation values between the two groups (mean ± SD)

Index	Group	Before anesthesia induction	Immediately after tracheal intubation	30 min after start of surgery	Immediately after extubation	5 min after extubation
rSO2 (%)	A (n = 59)	73.40 ± 4.40	66.18 ± 2.94	67.40 ± 2.86	69.04 ± 3.10	72.26 ± 3.35
	B (n = 58)	74.53 ± 3.78	64.07 ± 3.11	64.67 ± 3.15	66.12 ± 3.76	71.54 ± 3.43
	t	-1.489	3.772	4.910	4.587	1.149
	P value	0.139	0.000	0.000	0.000	0.253
BIS	A (n = 59)	93.78 ± 1.65	48.40 ± 2.44	51.73 ± 2.73	56.20 ± 3.45	89.76 ± 2.80
	B (n = 58)	93.16 ± 1.73	49.23 ± 2.61	52.50 ± 2.87	57.43 ± 3.61	88.72 ± 3.41
	t	1.984	-1.777	-1.487	-1.884	1.804
	P value	0.050	0.078	0.140	0.062	0.074

rSO2: Regional cerebral oxygen saturation; BIS: Bispectral index.