Application of dexmedetomidine combined with nitroglycerin in the treatment of deliberated hypotension of patients suffered from oral and maxillofacial tumor

JIANG Xigang; BIAN Qingming; XIAO Gang

doi:10.3969/j.issn.1674-4136.2015.03.010

Abstract：Objective To explore the efficacy and safety of controlled hypotension induced by dexmedeto-midine combined with nitroglycerin in patients with oral and maxillofacial tumor. Methods A total of 45 ASA I~Ⅱpatients with oral and maxillofacial tumor undergoing elective oral and maxillofacial surgery were randomly divided into three groups, group D,group N and group DN, with 15 cases in each group. All patients were re-ceived propofol total intravenous anesthesia (TIVA). In group D, patients were received dexmedetomidine 1. 0μg·kg-1 10 mins before anesthesia induction and followed by 0. 4~0. 8 μg·kg-1·h-1 continual infusion during maintenance, patients in group DN were received dexmedetomidine 0. 5μg·kg-1 10 min before induction of an-esthesia and followed by 0. 5 μg·kg-1·h-1 continual infusion during maintenance, nitroglycerin was infused to induce controlled hypotension at the beginning of the operation. In group N, nitroglycerin was administrated from 1. 0 μg·kg-1·h-1 and titrated according to target MAP at the beginning of the operation. The target MAP was maintained between 60 and 70 mmHg during controlled hypotension. The values of MAP、HR、CO、CI、ACI were measured at the time points before induction( T0 ) , before intubation( T1 ) , 1 min after intubation( T2 ) , 15 mins after controlled hypotension( T3 ) , at the time of extubation ( T4 ) . The pump speed of nitroglycerin, the time to target BP, the recovery time and extubation time were also recorded. Results Compared with T0 , sig-nificant decrease in MAP, HR were observed in group D, group DN at T1, T2, T3(P<0. 05 or P<0. 01), MAP, HR in group D and group DN were obviously lower than those of group N at T1 ,T2 , T4 time points( P<0. 05). No significant changes in CO, CI, ACI were seen in all groups (P>0. 05). In group DN, pump speed of nitroglycerin were lower than those of in group N, the time to target BP were also shorter than those of in group N(P<0. 05). but the recovery time and extubation time in group D+N were longer than those of in group N (P<0. 05). Conclusions It is more effective and safe in the treatment of controlled hypotension by u-sing dexmedetomidine plus nitroglycerin in patients with oral and maxillofacial tumor than using dexmedetomi-dine or nitroglycerin alone, with less influence on hemodynamic changes, but it may prolong the recovery time and extubation time.