Abstract: PURPOSE: To investigate the effect of atropine and different doses of penehyclidine hydrochloride on postoperative cognitive function in elderly patients undergoing oral and maxillofacial surgery. METHODS: One hundred and thirty-four elderly patients undergoing oral and maxillofacial surgery at Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine from December 2017 to July 2018 were included in the study. The patients randomly received atropine 0.5 mg (group A, n=32), penehyclidine hydrochloride 0.01 mg/kg (C1 group, n=34), penehyclidine hydrochloride 0.015 mg/kg (C2 group, n=33), normal saline (NS group, n=35) as preoperative medication. Preoperative anxiety scores, preoperative cognitive function scores, changes in vital signs after drug administration, degree of oral gland secretion, operation time, blood loss, recovery time, postoperative pain assessment, and postoperative cognitive function scores were compared between the four groups using SPSS18.0 software package. RESULTS: The changes of heart rate in group A was significantly higher than that in the other three groups (P<0.05). The number of oral secretions of patients in group A, C1 and C2 was significantly lower than that in the control group (P<0.05). The recovery time of C2 group was significantly longer than that of the other three groups (P<0.05), and the MMSE score was significantly decreased (P<0.05). CONCLUSIONS: Low dose (0.01 mg/kg) of penehyclidine hydrochloride before anesthesia induction does not prolong the recovery time, increase the risk of postoperative cognitive decline. At the same time, 0.01 mg/kg penehyclidine hydrochloride inhibits the secretion of salivary gland, and has little effect on cardiopulmonary system in elderly patients undergoing oral and maxillofacial surgery.

Key words: Oral and maxillofacial surgery, Penehyclidine hydrochloride, Elderly patients, Cognitive function