Controlled Hypotension With Remifentanil Duringen Doscopic Sinus Surgery

Objective To investigate the effects,Quality of the surgical field and influence to the stress response of Controlled hypotension with remifentanil under anesthesia of isoflurane during endoscopic sinus surgery.Methods 40 patients aged 20～60 undergoing selective endoscopic sinus surgery,ASA gradeⅠ～Ⅱ,were randomly assigned into R and F group.They had not serious disease on heart,lung,liver,kidney and brain.Their blood glucose were normal.They were not received medication for glucocorticoid and apium before.A 22-gauge catheter was inserted into a radial artery for direct determination of arterial blood pressure(SBP,DBP and MAP)and heart rate(HR)which were continuously recorded.They were received anesthesia with isoflurane(0.4 vol%～1vol%)constant inhalation and vecuronium(0.5～1μg·kg^-1·min^-1)constant infusion immediately after conventional induction of anesthesia. Remifentanil(0.3～0.8μg·kg^-1min^-1)constant infusion was used in group R to keep mean arterial pressure between 60 and 80 mmHg.So was sodium nitroprusside(0.5～3μg·kg^-1 min^-1)in group F.The blood pressure,MAP and HR of the two group were recorded at the time before and after induction and stage during Controlled hypotension. Quality of the surgical field were rated every 10 minutes during Controlled hypotension(Rating standard:FrommeⅠ～Ⅴdegree).Blood pressure and heart rate trend of the time points before and every 5 minutes during nasal sinus operation were recorded. Blood glucose and cortisol at the time before induction(T1),before surgery(T2)and 45 minutes to 60minutes from the beginning of the operation during controlled hypotension(T3)were recorded.All data were analyzed with the statistical software of SPSS 11.2.Chi square test were used for numeration data.The measurement data met homoscedasticity presented as (?)±s were tested by t-test and variance analysis,otherwise by rank sum test.α=0.05.The threshold for statistical significance was taken as P＜0.05.Results The SBP,MAP of the two group during Controlled hypotension were lower(P＜0.01),and the HR were lower(R group P＜0.01 but F P＜0.05)compared with those before anesthesia.The SBP,MAP,HR during controlled hypotension of R group were lower than those of F(P＜0.05).Quality of the surgical field rated of R group were significantly better(P＜0.01)during Controlled hypotension compared with F.Blood glucose and cortisol level at each T1,T2 and T3 are not significantly different between the two group with convariance analysis.Blood glucose level at T3 is not significantly different compared with T1 and T2,but cortisol is lower of each group(P＜0.01).The SBP,MAP,HR of group F fluctuated obviously during the sinus operation and have a rising tendency.But it was not the same as those of group R,the HR of group R even have a declining tendency slightly(P＜0.05).It is revealed that the blood pressure and heart rate appear relatively stable of R group than those of F from the trend graph.Conclusions Compared with sodium nitroprusside,controlled hypotension was achieved satisfactorily with remifentanil under anesthesia of isoflurane accompanying with better quality of the surgical field and inhibition to stress response.