Clinical observation of the effects of dexmedetomidine hydrochloride on cadiovascularcardiovascular response to tracheal extubation

Objective To observe the effects of dexmedetomidine hydrochloride on cardiovascular response to tracheal extubation. Methods One hundred ASA Ⅱ or IE patients regardless of sex aged 30 yr ～60 yr with a standard body weight±20% scheduled for gastrointestinal surgery under general anesthesia were randomly divided into 2 groups (n=50):propofol group (group P) and dexmedetomidine hydrochloride group (group D). Patients were transported into the postanesthetic recovery room after surgery. Patients in group P were maintained with propofol with a plasma target concentration at 1 mg/L. Patients in group D were injected loading dose and maintenance dose of dexmedetomidine hydrochloride at the rate of 0.5 μg/kg (10 in infusion) and 0.5 μg·kg-1·h-1, respectively. All infusions were discontinued when patients of both groups restored spontaneous breathing. BP, HR, and cough response were recorded at preoperative period (T0), immediately transportd into postanesthetic recovery room (T1), 10 mins after administration (T2), spontaneous breathing (T3), extubation (T4), 10 mins after extubation (T5). End -tidal anesthetic concentration, spontaneous breathing time, eyes open time given stimulation, extubation time, visual analog score and side effects were recorded. Results SBP, DBP and HR at T4 were respectively (124±15), (79±11),(74±10) mm Hg(l mm Hg=0.133 kPa) in group D. SBP, DBP and HR at T4 were respectively(143±21 ),(87±13),(93±8) mm Hg(P<0.05). SBP, DBP and HR at T5 were respectively (120± 13.5),(75±8),(75±9) mm Hg in group D. DBP and HR were respectively (128±22), (80±12),(83±10) mm Hg (P<0.05). Spontaneous breathing and eyes open time was (4±3),(4±4) min in group D, which were (6±5),(8±5) min in group P (P<0.05). The cough response was 3 case in group D, which was 23 case in group P (P<0.05).VAS score were (3.6±2.0) in group D, which were(5.5±3.l) in group P(P<0.05). Compared with T0, SBP and DBP at T4 were respectively (143±21),(87±13) mm Hg in group P(P<0.05), HR at T4 and T5 were respectively (93±8) beats/min and (83±10) beats/min in group P (P<0.05). Conclusion Dexmedetomidine (DEX) hydrochloride could efficiently prevent the adverse cardiovascular response to tracheal extubation and improve the quality of extubation. Key words: Dexmedetomidine hydrochloride;  Extubation;  Cough;  Adverse cardiovascular response