Clinical Observation Of Pre-controlled Hypotension With Sodium Nitroprusside In Nasal Endoscopic Surgery

Purpose:To observe the effect of pre-controlled hypotension in nasal endoscopic surgery with sodium nitroprusside on the hemodynamic changes,the quality of surgical field,the metabolism of lactic and renal function.Methods:Sixty patients(American Society of Anesthesiologists physical status Ⅰand Ⅱ)scheduled for elective endoscopic sinus surgery were enrolled in this study.Man or woman was allowed.The patients were randomly allocated to one of two parallel groups(S group,n=30;D group,n=30).The time of S group to controlled hypotension was after general anesthesia induction and before packing epinephrine.However,the time of D group to controlled hypotension was blood pressure achieve the peak cause by epinephrine or at the beginning of surgical procedures.The target was maintained mean arterial pressure(MAP)range from 50 mmHg to 65 mmHg.The data we have collected include the blood pressure in the process of packing epinephrine,the quality of surgery field of 10 minutes,20 minutes,30minutes,40 minutes after the start of operation.The venous blood samples were taken before operation and 24 hours after operation to determine kidney functions.The arterial blood samples were taken before operation and the time after controlled hypotension to determine blood gas analysis.Results:1.There was no significant difference in the operation time,SSFQ and the bleeding volume between the two groups(P>0.05).2.There were significant difference in the peaked and minimun SBP,DBP,MAP in the process of packing epinephrine between the two groups(P<0.01).The values of fluctuate were not significant between the two groups(P>0.05).The hypertension rate in group D was significantly above group S(P<0.05),the rate of hypotensionwas not significantly different between the two groups(P>0.05).3.Compare with pre-operation,there was no significant changes of lactic acid after controlled hypotension(P>0.05);The lactic acid concentrations were not significant different between the two groups(P>0.05).4.Compare with pre-operation,the Cr concentrations measured 24 hours in postoperation were no significantly increased in group S(P>0.05).Compare with pre-operation,the Cr concentrations measured 24 hours after surgery were significantly increased in group D(P<0.05),though their values were still within normal range.The two groups have no significantly difference.Compare with pre-operation,the BUN concentrations measured 24 hours after surgery were no significantly increased in two groups(P>0.05).There was no significant difference between the two groups(P>0.05).Conclusions:Compare with traditional CH,pre-controlled hypotension by sodium nitroprusside in nasal endoscopic surgery could maintain more stabilized arteral blood pressure and decrease hypertension rate,it also could maintain tissue blood perfusion,the balance of oxygen supply and oxygen consumption.However,it could not decrease the blood loss and improve the quality of operating field.