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Objective To evaluate the feasibility of using stroke volume variation (SVV) as the left ventricular preload to draw the cardiac function curve.Methods Twenty-seven patients of both sexes,aged 18-64 yr,with body mass index of 18-30 kg/m2,of American Society of Anesthesiologists physical status Ⅱ (New York Heart Association Ⅱ),with abnormal cardiac function,scheduled for elective offpany coronary artery byp grafting,were enrolled in this study.Twenty-five patients,aged 18-64 yr,with body mass index of 18-30 kg/m2,of American Society of Anesthesiologists physical status Ⅰ (New York Heart Association Ⅰ),with normal cardiac function,scheduled for elective non-cardiac surgery,were also enrolled in this study.SVV and SV were monitored by using a FloTrac/VigileoTM system.The patients were in the supine position from the end of anesthesia induction to the beginning of surgery.After the hemodynamics was kept stable for 5 min,SVV and SV were recorded.6％ hydroxyethyl starch 130/0.4 500 ml was intravenously infused over 20 min.SVV and SV were recorded after volume expansion.Spearman rank-order correlation was used to analyze the relationship between SVV and SV.The quadratic regression analysis was used to draw the SVV-SV curve,and the SVV-SV curve was compared with the Frank-Starling curve.Results Compared with the value before volume expansion,SVV and HR were significantly decreased,and SV was increased after volume expansion in the patients with normal cardiac function,and SVV was decreased after volume expansion in the patients with abnormal cardiac function (P＜0.01).SVV was negatively correlated with SV in the patients with normal cardiac function,and r=-0.467 (P＜0.05).SVV was negatively correlated with SV in the patients with abnormal cardiac function,and r=-0.378 (P＜0.05).The mirror symmetry was found between the SVV-SV curve in the patients with normal cardiac function and the normal Frank-Starling curve,and the general trend was close.The symmetry was not detected between the SVV-SV curve in the patients with abnormal cardiac function and the Frank-Starling curve in the patients with decreased myocardial contractility,and the general trend was not close.Conclusion For the patients with normal cardiac function,SVV can be used as the left ventricular preload to draw the cardiac function curve.
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Objective To evaluate the effects of lidocaine in combination with sevoflurane on myocardial protection in patients undergoing off-pump coronary artery bypass grafting (OPCABG).Methods One hundred ASA physical status Ⅱ or Ⅲ and NYHA class Ⅰ or Ⅱ patients of both sexes,aged 45-70 yr,weighing 63-82 kg,scheduled for elective OPCABG,were randomly assigned into 4 groups (n=25 each):control group (group C),lidocaine group (group L),sevoflurane group (group S),sevoflurane combined with lidocaine group (group SL).Tracheal intubation was performed after induction of anesthesia.Anesthesia was maintained with iv infusion of propofol and intermittent iv boluses of sufentanil and pipecuronium.Bispectral index value was maintained at 45-55.Lidocaine 1.5 mg/kg was injected after intubation,followed by infusion at 2 mg/min until the end of surgery in L and SL groups.Sevoflurane was inhaled with end-tidal concentration of 2.2％-2.5％ starting from the end of intubation until the end of operation in S and SL groups.Before induction of anesthesia,at skin incision,immediately after transsection of internal mammary artery,after completion of anastomosis of the proximal aortovein and distal coronary artery,at the end of operation and at 24 h during operation,venous blood samples were obtained to detect the levels of plasma creatine kinase (CK),creatine kinase isoenzyme-MB (CK-MB) and cardiac troponin Ⅰ (cTnI).Lidocaine-related side effects such as arrhythmia,bradycardia or cardiac arrest were recorded during operation and within 24 h after operation.Results Compared with group C,the plasma CK,CK-MB and cTnI levels were decreased in the S,L and SL groups.The plasma CK-MB and cTnI levels were significantly lower in SL group than in L group.The plasma CK,CK-MB and cTnI levels were significantly lower in SL group than in S group.In L and SL groups,no patient developed lidocainerelated side effects.Conclusion Lidocaine 1.5 mg/kg injected intravenously after intubation,followed by infusion at 2 mg/min in combination with sevoflurane end-tidal concentration about 2.2％ ～2.5％ provides myocardial protection in patients undergoing OPCABG,the efficacy is stronger than that of either alone.
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Objective To evaluate the blood-saving effect of combination of hemocoagulase artox for injection and tranexamic acid (TXA) in patients undergoing off-pump coronary artery bypass grafting (OPCABG).Methods Eighty ASA Ⅱ patients (NYHA Ⅰ or Ⅱ),aged 50-70 yr,weighing 50-100 kg,scheduled for elective OPCABG,were randomly divided into 4 groups (n =20 each):control group (group C),hemocoagulase atrox for injection group (group H,n =20),TXA group (group T) and hemocoagulase atrox for injection + ·TXA group (group HT).Hemocoagulase atrox 0.04 U/kg (the highest dose 4 U) was injected at 20 min before skin incision,and additional hemocoagulase atrox 2 U was given every 2 h starting from 15 min after administration of protamine until the end of operation in group H.TXA 20 mg/kg was injected intravenously at skin incision,followed by a continuous infusion of TXA at 10 mg· kg-1 · h-1 until the end of operation in group T.Hemocoagulase atrox and TXA were given as the method described in groups H and T.Venous blood samples were taken from the central vein before operation,at the end of operation,and 24 h after operation to determine the plasma D-Dimer concentration.The amount of blood loss,allogeneic red blood cells and plasma infused during operation,volume of drainage during 0-6 and 6-24 h after operation,total volume of drainage and volume of allogeneic blood transfused during operation were recorded.The deep vein thrombosis was recorded.Results Compared with group C,the amount of blood loss during operation was significantly decreased in groups T and HT,and the allogeneic red blood cells and plasma infused during operation,and volume of drainage during 0-6 and 6-24 h after operation,and total volume of drainage were significantly decreased in groups H,T and HT (P ＜ 0.05).Compared with groups H and T,the allogeneic red blood cells and plasma infused during operation,and volume of drainage during 0-6 and 6-24 h after operation,and total volume of drainage were significantly decreased in group HT (P ＜ 0.05).No deep vein thrombosis was observed in the 4 groups.Conclusion The combination of hemocoagulase artox for injection and TXA provides better blood-saving effect than either alone for the patients undergoing OPCABG without increasing the risk for thrombosis.