Different Concentration Of Sevofluarne Combined With Remifentanil Anaesthesia For Laparoscopic Cholecystectomy

Objective: The objective of this study is to determine the properconcentration of sevoflurane when combined with remifentanilanaesthesia for laparoscopic cholecystectomy. On the premise of ensuringthe quality of anaesthesia, our aim is to obtain a faster recovery time.Method:100patients, ASA I^II, aged30⁶0years old, arescheduled for the laparoscopic cholecystectomy. Patients wererandomized to the1.0MAC group（n=50） or1.5MAC group（n=50）. In theoperating room, standard monitoring was established, including BP, HR,SpO₂, P_ETCO₂and BIS. Patients with oxygen mask breathing （6L/min）were performed. Midazolam0.02⁰.04mg·kg^-1, sulfentanyl0.3⁰.6μg·kg-1, propoful1.5².0mg·kg^-1, cis-atracurium0.15mg·kg^-1areadopted for anesthesia induction. After anesthesia was induced,endotracheal intubation was completed and the patient’s lungs wereventilated by a Ventilator. Prime setting: breathing rate （f）=12times·min-1,VT=8.0mL·kg-1, O12flow=6.0L·min-. According to end-tidal carbondioxide pressure (P_ETCO₂), f and VT were adjusted. The1.0MAC or1.5MAC end-tidal concentration were achieved by ventilation with aninitial inspired sevoflurane concentration of8.0%until the requiredconcentration were recorded on the analyzer. Then O2flow was adjustedto2.0L·min^-1. Following the intubation, the remifentanil infusion wasstarted at a rate of12.0μg·kg^-1·h^-1. Flurbiprofen axetil1.0mg·kg^-1wasfollowed by the removal of the gall bladder. Sevoflurane werediscontinued immediately following the retreating of laparoscopic Trocar from the enterocoelia. Then O2flow was adjusted to6.0L·min^-1.After the intubation of the patients, BP, HR, SpO₂, P_ETCO₂and BISwere monitored continuously by Philips MP40Multifunctional vital signsmonitor. During the anaesthesia, the value of MAP and HR were recordedat the time before induction（T1）, immediately after intubation（T2）,sevoflurane percentage end-tidal equals MAC value（T3）, immediatelyafter pneumoperitoneum（T4）,10min after pneumoperitoneum（T5）,immediately after extubation（T6）,5min after extubation（T7）. Somatic-,autonomic-and haemodynamic responses were recorded to assess thequality of anaesthesia. In case of these responses, a treatment algorithmwas followed as described in Table3.1.Following discontinuation, the recovery times （time to spontaneousrespiration, opening eyes, extubation, modified Aldrete score≥9,discharge） were recorded. Appearance of nausea and vomiting, dysphoriawere recorded.Result:1. During the maintaince of sevoflurance, the MAP, HR, BIS weremaintained in a proper fields. The incidence of hypotension wassignificantly greater in the1.5MAC group （p＜0.05）.2. Significantly faster recovery times （time up to spontaneousrespiration, opening eyes, extubation, modified Aldrete score≥9,discharge） were found in the1.0MAC（p＜0.05）.3. No significant differences were found between the two groups inthe frequency of nausea and vomiting, dysphoria.Conclusion:1.0MAC sevoflurane provided a better quality of anaesthesia and a faster recovery times for laparoscopic cholecystectomy compared with1.5MAC sevoflurane，which would contribute to accelerating the clinicalturnaround time.