Effect of dexmedotomidine infusion in obstructive sleep apnea hypopnea syndrome patients undergoing nasal intubation

Objective Dexmedotomidine is characterized with effects of sedation,analgesia,amnesia and lack of respiratory depression.So it should be suitable for obstructive sleep apnea hypopnea syndrome(OSAHS)patients undergoing nasal intubation.Methods Seventy ASA physical statusⅡor Ⅲ OSAHS male patients with anticipant difficult airways who were undergoing elective surgery were enrolled and randomly allocated into two groups;the Dex group(group D,n=36)that received dexmedetomidine 0.6 μg/kg infusion for 10 minutes and the Control group(group C,n=34)that received normal saline infusion for 10 minutes.Anesthesia was induced with sufficient superficial anesthesia and pethidine 50 mg and dropreridol 1 mg injected through vein in both groups.During the intubation,all patients maintained a spontaneous respiratory pattern.An ID=7 mm tracheal tube was passed nasally over the fiberscope and its position checked using the fiberscope.Fibreoptic intubation was started when a dexmedetomidine infusion or normal saline infusion provided a sedation in which patients appear to be sleepy but,if stimulated(shout or tap),were easily roused,cooperative,and communicative.Systolic blood pressure(SP),heart rate(HR),heart rate and systolic blood pressure product(RPP),pulse oxygen saturation(SpO2)and adverse effects were recorded at baseline(T0),the time after infusion DEX or saline infusion(T1),1 min after tracheal intubation(T2),and 3 min after tracheal intubation(T3).The patients were mechanically ventilated after nasal intubation.Results A total of 70 patients were enrolled into the study.There were no differences between the baseline data of the two groups(P0.05).All patients underwent successful nasal fibreoptic intubation.(1)Changes of HR.In group D,the HR was significantly decreased at T1,T3 compared with T0(P0.01).HR was significantly increased at T2 compared with T0 in group C(P0.01).HR were much lower in any-point-in-time of group D than those of in group C except at baseline(T0)(P0.01).(2)Changes of SP.SP in group D during tracheal intubation were more stable than those in group C(P0.01).ANOVA indicated that no significant changes were observed at T1,T2,T3 compared with T0 in group D(P0.05).SP was significantly increased at T2 compared to T0 in group C(P0.01).SP was significantly increased at T2,T3 in group C than those of in group D(P0.01).(3)Changes of RPP.RPP were much lower at T1,T3 than that of at T0,while RPP were higher at T2 than that of at T0(P0.01)in group D.RPP were significantly higher at T2 than that of at T0 in group C(P0.01).RPP were significantly decreased at T2,T3 in group D than those of in group C(P0.01).(4)SpO2:there was no significantly difference between the two groups at any-point-in-time(P0.05).Conclusions Dexmedetomidine infusion before anesthetic induction could effectively blunt the cardiovascular response to nasal intubation in patients with OSAHS.