OBJECTIVE: To probe into the protective effects of dexmedetomidine combined with sufentanil on cerebral oxygen metabolism and liver function in elderly patients during recovery from general anesthesia. METHODS: A total of 90 patients undergoing surgery in the hospital from Jan. 2020 to Jan. 2021 were selected as the research objects. The patients were divided into the group A（n=30）

group B（n=30） and group C（n=30） according to the random number table method. Patients in group A were treated with dexmedetomidine combined with sufentanil by continuous pumping to maintain anesthesia

the group B were given sufentanil alone

and the group C received 0.9% sodium chloride injection. The incidence of agitation and visual analogue scale（VAS） at different time points were compared among three groups. The heart rate（HR） and mean arterial pressure（MAP） levels before and after surgery were recorded; the cerebral oxygen metabolism [suturation jugular venous blood（SjvO

2

）

cerebral oxygen extraction rate（CERO

2

）] was recorded before anesthesia induction（T

0

）

at the end of surgery（T

3

） and after surgery of 24 h（T

4

）. The levels of alanine aminotransferase（ALT） and aspartate aminotransferase（AST） at T

0

skin incision（T

1

）

5 min after tracheal intubation（T

2

）

T

3

and T

4

were detected in three groups. RESULTS: The MAP and HR levels of three groups before surgery

after surgery of 1 h and 2 h increased first and then decreased. There were significant differences in levels of MAP and HR among three groups after surgery of 1 h and 2 h（P

<

0.05）. The incidences of agitation in group A

B and C were respectively 3.33%（1 case）

6.67%（2 cases）and 26.67%（8 cases）

the difference was statistically significant（P

<

0.05）. There were statistically significant differences in VAS scores within three groups before surgery

after surgery of 1 h and 2 h（P

<

0.05）

which decreased first and then increased. There were significant differences in VAS scores among three groups after surgery of 1 h and 2 h（P

<

0.05）. There were statistically significant differences in SjvO

2

and CERO

2

among three groups at T

3

and T

4

（P

<

0.05）. From T

1

to T

4

there were significant differences in levels of ALT and AST among three groups（P

<

0.05）. CONCLUSIONS: Dexmedetomidine combined with sufentanil can reduce the cardiovascular stress and restlessness response of elderly patients during recovery from general anesthesia

and alleviate the pain of patients to a certain extent

improve the cerebral oxygen metabolism

alleviate the brain injury level

effectively inhibit the liver injury and protect the residual liver function of patients.