Effect Of Controlled Hypotension With Sodium Nitroprusside On Bispectral Index

Object:To investigate the effects of controlled hypotension with sodium nitroprusside on Bispectral Index in patients during propofol anesthesia.Methods:Thirty ASAâ… -â…¡patients aged between 22-60 yr and weighing 48-95 kg undergoing selective laparoscopic cholecystectomy,were randomly divide into two groups(n=15). Propofol group(group P) and Sodium nitroprusside group(group S). All the patients anaesthesia were dnduced with propofol 2mg/kg,fentanyl 3ug/kg,atracurium 0.8mg/kg.After tracheal intubation,adjust the dosage of propofol continuous vein input to maintain bispectral index(BIS) with 55-60,stabilized 30 minutes. Depressurization was achieved by continuous infusion of 0.01% sodium nitroprusside to mean arterial pressure(MAP)levels of 40% elementary MAP, stabilized 5 minutes.MAP,HR,BIS,CO,SV and SVR were measured invasively pre-induction(T0),pre- treatment(SNP or saline T1) and after depressurization (40% elementary MAP,T2).Results:After propofol was continuous infused and BIS stablized with55-60 ,the value of the MAP,HR,CO,SV,SVR all decreased (P<0.01). when MAP decreased to 40% elementary value by SNP, Heart rate increased while the blood pressure decling. But CO and SV have no conspicuous change(P>0.05),SVR value decreased significantly(p<0.01), BIS value decreased (P<0.05).Conclusion:Sodium nitroprusside controlled hypotension in 40% elementary MAP will alter the Bispectral index during anaesthesia with propofol. With the decrease of MAP, the value of BIS will decreased . Anaesthetist should pay attention.