A Clinical Study Of Different Dosage Dexmedetomidine Combined With Etomidate-Lipuro During Painless Colonoscopy

Background:With the development of modern medicine, the improvement of living conditions, the strengthening of healthcare, more and more patients would like to preceed a colonoscopy examination. The implementation of electronic colonoscopy examination under anesthesia, not only can eliminate patient anxiety, tension, fear, and improve the accuracy of electronic colonoscopy examination, but also can improve the toerance of patients, improve the patient’s subjective symptom, and decrease the difficulty of endoscopic operation. We wish that patients are safe, feel comfortable and satisfied during endoscopic operation, and wake up quickly without discomfort after examination. Propofol is a common drug used in painless colonoscopy, but propofol can cause a transient inhibition of respiration, combined with opioid drugs can aggravate respiratory inhibition and delayed recovery, and results in the hemodynamic instability, the agitation and delirium in the period of recovery. Although the incidence of severe cardiopulmonary complications in endoscopic examination is low, respiratory depression is one of the main causes of death in colonoscopy. Respiratory depression is the biggest concern in painless colonoscopy.Etomidate is clinical commonly used intravenous anesthetics with fast acting, no respiratory and circulatory depression etc and also used in painless endoscopy, but it is easy to cause the injection pain, myoclonus and complications such as nausea and vomiting in the inducible period. The use of etomidate-lipuro reduces the injection pain and the incidence of nausea and vomiting of etomidate, but the incidence of myoclonus is still high. Although there are many studies reported a single bolus and continuous infusion etomidate-lipuro injection is safe and feasible, and through the combine other drugs to reduce the myoclonus of etomidate-lipuro, such as midazolam, but the overall effect is not ideal. Dexmedetomidine is a new type of alpha2adrenoceptor agonist with sedative, analgesic and anti-sympathetic nerve function, which can reduce the amount of sedation and analgesic drugs, reduce the rate of cardiovascular adverse events, and no respiratory depression, as well as to get an unique physiological sleep state. Studies have shown that dexmedetomidine can reduce the incidence of etomidate myoclonus. However,it has been never reported that the clinical study of different dosage dexmedetomidine combined with etomidate-lipuro during painless colonoscopy.Objective:To investigate the effect and safety of pretreatment of different dose of dexmedetomidine in colonoscopic patients anesthetized with etomidate-lipuro. Methods:Eighty patients scheduled for painless colonoscopy were divided into four groups by random digit table.0.9%sodium chloride solution (control group),0.6μg/kg,1.0μg/kg and1.4μg/kg dexmedetomidine were given intravenously, respectively, before application of etomidate-lipuro. The dosage of etomidate-lipuro, hemodynamic parameters, recovery time, discharge time, the incidence of myoclonus, postoperative complications, and doctors’and patients’ satisfaction were assessed in all patients.Results:The induction doses and total doses of etomidate of the three dexmedetomidine groups were significantly less than those of the control group (P<0.05). There were no significant differences in the duration of colonoscopy and recovery time between four groups (P>0.05). The discharge time of dexmedetomidine0.6μg/kg and1.0μg/kg groups was significantly shorter than that of dexmedetomidine1.4μg/kg group and control group (P<0.05). There were no significant differences in MAP, HR and SpO2at To between four groups (P>0.05). MAP at T1-T5in control group, and dexmedetomidine0.6μg/kg and1.0μg/kg groups were significantly lower than those in dexmedetomidine1.4μg/kg group (P<0.05). HR at Ti, T2, T4and T5in dexmedetomidine0.6μg/kg and1.0μg/kg groups were significantly lower than those in the control group (P<0.05). SPO2at Ti and T2in control group, and dexmedetomidine0.6μg/kg and1.0μg/kg groups were significantly higher than those in dexmedetomidine1.4μg/kg group (P<0.05). The incidence of myoclonus, nausea and vomiting of the three dexmedetomidine groups were significantly lower than those of the control group (P<0.05). No significant differences were observed in the incidence of injection pain and dream between four groups (P>0.05).Doctors’ satisfaction of the three dexmedetomidine groups was significantly higher than that of the control group(P<0.05). Patients’ satisfaction of dexmedetomidine0.6μg/kg and1.0μg/kg groups was significantly higher than that of dexmedetomidine1.4μg/kg group and control group (P<0.05).Conclusion:A single dose of0.6μg/kg or1.0μg/kg dexmedetomidine pretreatment combined with etomidate-lipuro for anesthesia are effective and safe during painless colonoscopy.