Effect of different doses of dexmedetomidine combined with midazolam on awakening endotracheal intubation

Xiao Yan; Zhang Ying; Zhang Jiao

doi:10.3969/j.issn.1672-8157.2025.03.031

Abstract：Objective To evaluate the efficacy and safety of varying doses of dexmedetomidine in conjunction with midazolam in awakening endotracheal intubation guided by fiberoptic bronchoscopy.Methods A total of 70 patients with preoperative assess-ment of difficult airway in the Second People's Hospital of Meishan City from October 2022 to November 2023 were selected and divided into three groups using the randomized numerical table method:the low-dose dexmedetomidine combined with midazolam group(the LD group,n=23),the high-dose dexmedetomidine combined with midazolam group(the HD group,n=24),and the midaz-olam group(the C group,n=23).Midazolam 0.03 mg·kg-1 i.v.was given to the LD and HD groups,and midazolam 0.06 mg·kg-1 i.v.was given to the C group.Dexmedetomidine 0.5 μg·kg-1,0.7 μg·kg-1,and saline were given to the LD,HD and C groups,respectively.The baseline data,haemodynamic indexes,success rate of one-time intubation,intubation time,tolerance score during intubation and incidence of adverse reactions were observed and compared among the groups.Results The HR and MAP of the three groups were respectively(69.43±6.16)times·min-1,(76.74±6.43)mm Hg(1 mm Hg≈ 0.133kPa),(68.92±5.57)times·min-1,(75.24±5.85)mm Hg,(71.61±5.74)times·min-1 and(78.72±6.12)mm Hg at T1,lower than those at T0(t=6.964,4.475,7.326,5.958,5.456,4.053,all P<0.05),and there were no significant differences among the groups(P>0.05).The HR and MAP of the three groups were respec-tively(83.62±5.48)times·min-1,(91.26±6.54)mm Hg,(78.45±5.76)times·min-1,(85.15±6.82)mm),(92.16±6.25)times·min-1 and(97.43±7.07)mm Hg at T2,higher than those at T1(t=8.254,7.593,5.827,5.403,11.614,9.802,all P<0.05).However,the HR and MAP of the HD group were lower than those of the C and LD groups(Fbetween group=32.928,19.077,P<0.05).Repeated measure-ment ANOVA showed that there were significant differences in the time main effect of HR(F=58.327,P<0.001),group main effect(F=9.842,P<0.001)and time×group interaction effect(F=6.954,P=0.002);there were significant differences in the time main effect(F=49.613,P<0.001),group main effect(F=7.215,P=0.001)and interaction effect(F=5.438,P=0.006)of MAP.Post-hoc comparisons results showed that the HR and MAP of the HD group were lower than those of the C group and LD group at T2(P<0.05).There was no significant difference in the success rate of primary tracheal intubation(82.61%(19/23),91.67%(22/24),73.91%(17/23))among the three groups(χ2=2.608,P>0.05).There were significant differences in the intubation time and tolerance score during intubation among the three groups(Fgroup=12.814,10.081,P<0.05).The intubation time was(45.10±9.26)s in the HD group,(53.37±9.84)s in the LD group,shorter than(59.43±10.15)s in the C group,and the intubation time of the HD group was shorter than that of the LD group(t=2.968,P<0.05).The scores of tolerance during intubation of the HD and LD groups were higher than those of the C group(t=3.449,4.152,P<0.05).There was no significant difference in the incidence of adverse reactions among the three groups(χ2=4.096,P>0.05).By between-group comparison,the incidence of adverse reactions was 16.67%in the HD group,lower than 43.48%in the C group(χ2=4.037,P<0.05).There was no significant difference between the LD group and the HD group,the LD group and the C group(χ2=2.207,0.365,P>0.05).Conclusion In fibreoptic bronchoscopy-guided awake tracheal intubation,0.7 μg·kg-1 dexmedetomidine in combination with midazolam provides better haemodynamic stability,improves patient intubation tolerance,shortens intubation time,and reduces the incidence of adverse reactions.