Clinical Study Of Tracheal Extubation Under The Level Of Sedation With Propofol Target-controlled Infusion Guided By Narcotrend

Objective:Emergence from anaesthesia and tracheal extubation may be associated with increases in arterial pressure, heart rate, RPP, plasma concentrations of catecholamine, intra-abdominal pressure, intraocular pressure, intracranial pressure and development of myocardial ischaemia in susceptible individuals. A bad memory produced during the extubation process will also cause a psychological damage to the patient and reduce patient’satisfaction to anesthesia. We have examined the effect of propofol on the haemodynamic response to emergence from anaesthesia and tracheal extubation under a certain depth of anesthesia (a level, C2-C0) maintained in propofol target-controlled infusion with Narcotrend monitoring in40ASA Ⅰ-Ⅱ female patients undergoing gynecological abdominal surgery, in a randomized, double-blind study. Taking the opportunity to assess the patient’s hemodynamic change, cough reflex, recovery time and whether producing a harmful memory during the endotracheal suction and extubation process.Methods:40patients ASA physical status I-II scheduling for elective gynecological abdominal surgery were randomly divided into two groups: observation group (N group) and control group (C group),20cases in each group. At the end of the operation, the patients in observation group were continued to keep a certain depth of anesthesia with propofol target-controlled infusion (Alaris PK6003pump, AstraZeneca) guided by Narcotrend. The predicted effect compartment concentration of propofol were adjusted to keep the value of Narcotrend Index (NI) in a steady range from65to79(C2-C0) and the control group without propofol. The observation indexes are:SBP, DBP, HR, RPP, NI and cough reflex at6time points before induction, at the end of surgery, endotracheal suction, extubation, extubation after5min and10min and the spontaneous respiration recovery time, recovery time, dwell time of PACU. Besise the adverse memory about extubation were also recorded.Results:(1) The systolic blood pressure, diastolic blood pressure and heart rate pressure product (RPP) at the points of endotracheal suction, extubation and extubation after5min were significantly different (p<0.05). At the same points of endotracheal suction and extubation, the difference of heart rate between the two groups were obviously different (p<0.05).(2) The value of Narcotrend Index (NI) were lower at the point of endotracheal suction, extubation and extubation after5min in observation group compared with control group (p<0.05):71.64±3.81,72.96±3.16,83.21±6.59vs84.24±4.68,86.44±4.07,89.22±3.98, respectively. The value of NI at the point of extubation in the observation group has a good correlation with the patient’s recovery hours, the R value is-0.727. The predicted effect-site concentration (EC) of propofol in the two groups at extubation were2.00±0.35ug/ml and0.46±0.16ug/ml,the95%confidence interval were1.84-2.17ug/ml and0.39-0.54ug/ml, respectively.(3) The spontaneous respiration recovery time and PACU dwell time between the two groups have no statistically significant difference (P>0.05) and the average recovery time in observation group was4.91±1.93min, in control group it was0min.(4) cough reflex at endotracheal suction and extubation was rated as5grades’0-1-2-3-4’. The degree of cough reflex were0(2)/1(9)/2(6)/3(3)/4(0) and0(4)/1(9)/2(5)/3(2)/4(0) in the observation group (N group);0(0)/1(3)/2(8)/3(9)/4(0) and0(0)/1(5)/2(8)/3(7)/4(0)in the controll group(C group). In the observation group (N Group) all patients had no extubation memory. The patients in controll group (C Group) complained of a bad memory both in endotracheal suction and extubation, but there are3cases of patients can not recall the process after extubation10min. There are3patients in observation group complained of an uncomfortable sense in throat24hours after surgery, the number of this situation is5in controll group.Conclusion:(1) Propofol, when given with target-controlled infusion guided by Narcotrend at the end of surgery, attenuated the haemodynamic fluctuation, cough reflex associated with emergence from anaesthesia and tracheal extubation and has played an important role of stabilizing cardiovascular and cerebrovascular system.(2) An adequate level of sedation (NI, C2-C0) which accepted by propofol target-controlled infusion guided by Narcotrend can eliminate the harmful memory related with extubation, alleviate the patients’ psychological damage and improve patients’satisfaction to anesthesia(3) In our study, the predicted effect-site concentration (EC) of propofol to maintain special period of C2-CO in Narcotrend neither affect the patients’spontaneous breathing recovery time, nor to extend the dwell time in PACU.