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20 % . In both groups CH was induced with infusion of 0.01 % NTP at a rate 0.5-6.0 ?g?kg-1?min-1 to maintain MAP at 55-65 mm Hg. MAP, HR, CVP and CO were continuously monitored. Arterial lactate concentration was measured by enzyme assay. Arterial and mixed venous blood gases were analyzed, and oxygen delivery (DO2 ) and consumption (VO2) were calculated before AHH (T0) after AHH was performed (T1), 30 min after CH was induced (T2) and 30 min after termination of CH (T3) in group Ⅰ and in group Ⅱ before CH (T1), 30 min after induction of CH (T2) and 30 rain after termination of CH (T3 ) .ResultsIn group Ⅰ(AHH + CH) compared with the baseline values (T0 ) HR significantly decreased while CVP significantly increased after AHH (T1 ) ; cardiac output (CO) significantly increased after AHH (T1 ) and during CH (T2) while DO2 was significantly decreased after AHH (T1) and CH (T3 ) but arterial lactate concentration was significantly decreased during and after CH (T2, T3). In group Ⅱ (CH alone) compared with the baseline values (T1) HR significantly increased while CVP significantly decreased during and after CH (T2, T3 ) ; there was no significant change in CO and DO2 at T2 and T3 but arterial lactate concentration significantly increased during and after CH (T2, T3). There was significantly less blood loss during operation in group I than in group Ⅱ . ConclusionThere was tissue deoxygenation during and after deliberate hypotension as shown by increased arterial lactate concentration while AHH combined with CH can improve tissue perfusion and oxygenation. AHH can also maintain hemodynamic stability during CH.
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ObjectIve To InvestIgate the balance between cerebral O2 supply and consumptIon and glucose metabolIsm durIng supratentorIal tumor resectIon under total Intravenous anesthesIa (TIVA) wIth propofol. Methods Twenty-four patIents of ASA grade Ⅰ- Ⅱ aged 20-55 undergoIng electIve supratentorIal tumor resectIon were randomly dIvIded Into 2 groups : lIdocaIne group (A, n = 12) and control group (B, n - 12) . After sedatIon wIth Intravenous scopolamIne 0.3 mg, mIdazolam 0.02 mg?kg-1 and droperIdol-fentanyl mIxture 0.03 ml? kg-1 radIal artery was cannulated for Bp monItorIng and blood samplIng and left Internal jugular veIn was cannulated retrogradely and the catheter was advanced cephalad untIl jugular bulb for blood samplIng. In lIdocaIne group anesthesIa was Induced wIth lIdocaIne 1.5 mg?kg1, propofol 2 mg?kg1, droperIdol-Ientanyl mIxture 0.04 ml?kg-1 and pIpecuronIum 0.15 mg ? kg1 and maIntaIned wIth propofol InfusIon at 6-8 mg?kg-1?h-1 and IntermIttent I. v. boluses of fentanyl and pIpecuronIum. LIdocaIne was Infused after InductIon of anesthesIa at 11.7 mg ?kg1? h-1 for 20 mIn then InfusIon was maIntaIned at 2 mg ?kg1? h-1 .In control group lIdocaIne was replaced by normal salIne. The patIents were mechanIcally ventIlated (VT 6-8 ml?kg1 , RR 12-14 bpm) and PETCO2 was maIntaIned at 29-31 mm Hg In both groups. Blood volume and hemodynamIcs were well maIntaIned durIng operatIon. Blood samples were taken from artery (a) and jugular venous bulb (jv) sImultaneously before InductIon of anesthesIa (T0, baselIne), at IntubatIon (T1), whIle tumor was beIng Isolated (T2) and resected (T3) and at the closure of dura (T4 ) , for blood gas analysIs and determInatIon of Hb and glucose and lactate concentratIon. The dIfference In arterIal and jugular bulb O, content ( Ca-jvO2 ) , cerebral O2 extractIon rate (O3ER), glucose extractIon rate ( GER) and lactate productIon rate (LacPR) were calculated. Results The two groups were comparable wIth respect to demographIc data, duratIon of operatIon and the amount of propofol and fentanyl used. SjvO2 was sIgnIfIcantly lower, Ca-jvO2 greater and O2ER hIgher at T1 In group A than In group B. There was no sIgnIfIcant dIfference In GER and LacPR between the two groups. ConclusIon A bolus of lIdocaIne 1.5 mg?kg-1can increase cerebral O2 extraction during induction and intubation but lidocaine infusion at 2 mg?kg-1?h-1 has no significant effect on cerebral O2 supply/demand and glucose metabolism.
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Objective To examine the hemodynamic changes and oxygen metabolism during off-pump coronary artery bypass grafting (OPCABG) .Methods Twenty patients (18 male, 2 female) aged (60?8)yr, weighing (71?9)kg undergoing OPCABG were studied. The patients were premedicated with diazepam 10 mg PO 2h before operation and morphine 10 mg and scopolamine 0.3 mg im 30 min before operation. Anesthesia was induced with midazolam 0.1-0.2 mg?kg-1, fentanyl 5-10 ug?kg-1 and vecuronium 0.12-0.15 mg?kg-1 and maintained with 0.5%-2% isoflurane inhalation, fentanyl 10-20 ug?kg-1 and intermittent iv boluses of vecuronium and in some patients propofol infusion. Radial artery was cannulated. Swan-Ganz catheter was placed via internal jugular vein into pulmonary artery. Hemodynamic parameters including MAP, HR, cardiac index (CI), stroke volume (SV), MPAP, PCWP, SVR, left ventricle stroke work index (LVSWI) and RVSWI; oxygen metabolism including oxygen delivery (DO2) , oxygen consumption (VO2) and oxygen extraction ratio (ERO2); regional cerebral oxygen saturation (rSCO2) and arterial blood lactate level (ABL) were measured and recorded before skin incision (A), when pericardium was incised before operation on the heart (B), during operation on the heart (C), 10 min after operation on the heart (D) and at the end of surgery (E) . Results During surgical manipulation on the heart (C) MAP, SV and CI decreased while CVP and HR increased, but the decrease in CI and SV was not significant. During manipulation on the heart(C) DO2 decreased whereas ERO2 increased, but there was no significant change in VO2. After manipulation on the heart (D) DO2 and ERO2 returned to the pre-manipulation level. Arterial blood lactate concentration increased at E. Conclusion OPCABG can be performed uneventfully under our general anesthetic regimen. During operation while the beating heart is being manipulated MAP tends to decrease while CVP and HR increase. The changes are of short duration and do not result in any serious consequeaces.
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Objective To evaluate the hemodynamic changes and oxygen metabolism during whole body hyperthermia (WBH) therapy in patients with malignant tumor. Methods Twenty ASA Ⅰ - Ⅱ patients with advanced cancer aged 22-58 yr were enrolled in the study. The patients were premedicated with midazolam 0.05 mg ?kg-1 and scopolamine 0.3 mg im. Anesthesia was induced with intravenous droperidol 5 mg, fentanyl 100 ?g, propofol 2 mg?kg-1 and vecuronium 0.15 mg?kg-1 . The patients were mechanically ventilated after tracheal intubation (FiO2 = 100%, RR=10-12bpm, VT = 8-12 ml?kg-1 ) and fentanyl (2?g?kg-1 ? h-1 ), 1%-1.5% isoflurane inhalation and intermittent iv boluses of vecuronium and midazolam. Swan-ganz catheter was placed in the pulmonary artery for hemodynamic monitoring. Radial artery was cannulated for direct BP monitoring and arterial blood gas analysis. ECG and PaO2 were continuously monitored. Body temperature probes were placed in esophagus, rectum, naso-pharynx and body surface. Body temperature was warmed to 41.8t and maintained for 2 h. Stroke volume(SV), cardiac output(CO), mean pulmonary artery pressure (MPAP), vascular resistance index (SVRI), pulmonary vascular resistance index (PVRI), oxygen delivery (DO2), oxygen consumption (VO2) and oxygen extraction rate (O2ER) were calculated before warming (T0), at 39℃ ,40℃ ,41℃ , 41.8℃,41.8 ℃(1 h), 41.8℃(2 h) and when T0 was decreased to 40℃ and 38.5t (T1-8) .Results HR, CI, SI, CVP, MPAP and PCWP significantly increased with increasing body temperature, while MAP, PVRI and SVRI significantly decreased. DO2 and VO2 increased by 35% and 18% at 39℃ , 55% and 23% at 40℃ , 70% and 28% at 41℃ and by 88% and 31% at41.8℃.During WBH O2ER, PvO2 P(a-v)CO2 and pH (a-v) were maintained within normal range. At 41. 8℃ (2h) pH was lower than the normal range, at the end of WBH, hemodynamic and O2 metabolism parameters gradually returned to baseline levels. Conclusion The balance between oxygen delivery and oxygen consumption can be well maintained during WBH therapy under general anesthesia.
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0.05). But the CaO2-CjO2 and jugular vein Glu level at D in group I were significantly lower than those at D in group C. In group C CaO2-CjO2 and jugular vein glutamate level at D were significantly higher than those at B (P
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Objective To investigate the effects of acute hypervolemic hemodilution (AHH) on cerebral O2 supply/consumption and energy metabolism in patients undergoing elective surgery under general anesthesia combined with continuous epidural block. Methods Fourteen ASA Ⅰ or Ⅱ patients of both sexes (9 male, 5 female) aged 44-62 yrs weighing 55-70 kg undergoing elective surgery under general anesthesia combined with epidural block were enrolled in this study. Lactated Ringer's solution 6-8 ml?kg-1 was infused before anesthesia. After correct placement of epidural catheter was confirmed radial artery was cannulated for BP monitoring and blood sampling. BP, EGG, SpO2 and PET CO2 were continuously monitored during anesthesia. General anesthesia was induced with fentanyl, midazolam, propofol and rocuronium and maintained with iaoflurane and intermittent i. v. boluses of vecuronium. The patients were intubated and mechanically ventilated. PET CO2 was maintained at 30-35 mm Hg. Epidural block was produced by a mixture of 1.33 % lidocaine + 0.167 % dicaine. Right internal jugular vein was retrogradely cannulated and advanced cephalad until jugular bulb for blood sampling. AHH was conducted by infusing 6% HES 20 ml?kg-1 at 50 ml?min-1 after induction of general anesthesia. Blood samples were taken from artery (a) and jugular venous bulb (jv) simultaneously before AHH (T0) at 15 min (T1) and 120 min (T2) after AHH was accomplished for blood gas analysis and determination of Hb, glucose and lactate concentrations. Cerebral O2 extraction rate (CERO2), glucose extraction rate (CMRglu) , arterial-jugular bulb venous O2 content difference (D a-jvO2) and arterial-jugular bulb venous lactate difference (VADL) were calculated. Results At the end of AHH Hct and Hb decreased by 20% as compared to the baseline values before AHH. S jvO2 was significantly higher, D a-jvO2 smaller and CERO2 lower at T1 than at T0. There were no significant differences in BP, HR, CMRglu and VADL at all time points. Conclusion AHH can increase cerebral O2 supply and has no significant effect on cerebral glucose metabolism during operation performed under general anesthesia combined with epidural block.