非体外循环冠脉搭桥术中的血液动力学和氧代谢的变化

目的 观察非体外循环冠脉搭桥术（OPCABG）中的血液动力学及氧代谢参数的变化,并分析其麻醉处理特点。方法 择期行OPCABG手术患者87例。均采用芬太尼、异氟醚、笑气、异丙酚行静吸复合全麻。采用肺动脉漂浮导管和连续心排血量方法测定血液动力学,分别在手术前（T1）、锯胸骨后（T2）、吻合血管桥前（T3）、吻合前降支时（T4）、吻合后降支或右冠状动脉时（T5）、吻合左回旋支或对角支时（T6）、血管吻合完成并恢复心脏自然位置（T7）、闭合胸骨前（T8）及手术结束时（T9）等时间点测定及计算血液动力学参数;分别在上述的T1、T2、T3、吻合开始后1.5h（T4-）、及T9的5个时间点检测动脉、混合静脉血气,并进一步计算氧代谢参数包括氧供8指数（DO2I）、氧耗指数（VO2I）、氧摄取率（ERO2）等。记录术后拔气管导管时间及ICU停留时间。结果 与T1相比,T2与T3的HR、CO、CI、PAWP、MPAP、LVWI、RVWI、RVSWI、DO2I、SO2、PO2均显著增加（P〈0.05或0.01）,而VO2I与ERO2明显降低（P〈0.05或0.01）,但SI、LVSWI和PVRI无显著性改变（P〉0.05）。在吻合靶血管过程中（T4、T5、T6）,CI、SI、MAP、LVWI、LVSWI、RVWI、RVSWI、DO2I、SO2、PO2、VO2I等不同程度地降低（P〈0.05或0.01）,而HR、RAP、MPAP、PAWP和ERO2则显著增高（P〈0.05或0.01）。血管吻合完毕后至术毕（T7、T8、T9）各项参数均逐渐恢复至T1水平或明显改善。术后平均6.5±2.3h拔除气管导管,ICU停留时间为2.6±1.4d。结论 在可靠的血液动力学监测和合理使用血管活性药物情况下,OPCABG病人可安全地渡过吻合靶血管时的循环波动期,恢复机体的氧供需平衡。     

尼卡地平对非心肺转流冠状动脉旁路移植术患者术中血流动力学和氧代谢的影响

目的 探讨尼卡地平对非心肺转流冠状动脉搭桥术(off-pump coronary artery bypass grafting,OPCABG)患者术中血流动力学和氧代谢的影响.方法 选择拟行OPCABG患者79例,年龄51～68岁,ASAⅢ或Ⅳ级,随机分为两组,近端血管吻合前分别持续泵注尼卡地平0.5 μg·kg-1·h-1组(N组,n=41)或硝酸甘油0.5 μg·kg-1·h-1组(G组,n=38).记录麻醉前(T0)和用药后10min(T1)、30min(T2)、60 min(T3)、90 min(T4)时的氧代谢、血流动力学等指标变化情况,包括SvO2、MAP、PaO2、CO、HR和肺血管阻力(PVR)、体循环血管阻力(SVR)、CI、氧摄取率(ERO2)、乳酸(Lac)等.结果 与T0时比较,T3,T4时两组患者氧耗明显降低,Lac浓度明显升高,且N组均明显低于G组(P＜0.05);T3,T4时G组PaO2、氧供明显降低,ERO2明显升高,N组PaO2、氧供明显高于,ERO2明显低于G组(P＜0.05).与T0时比较,两组T1～T3时PAP、T1～T4时PVR和SVR均明显降低,T3,T4时CI明显升高(P＜0.05),且T1～T4时N组PVR和SVR明显低于G组,T4时CI明显高于G组(P＜0.05).两组患者均顺利完成手术,术后均无严重并发症发生.结论 尼卡地平可有效改善OPCABG患者术中氧代谢并维持血流动力学稳定.     

Myocardial oxygen balance during hemodilution in patients undergoing coronary artery bypass grafting

The myocardial (arterial-coronary sinus) balance of oxygen and lactate was studied before a cardiopulmonary bypass and during the first 5 min of a normothermic bypass in two patient groups undergoing coronary revascularization for multiple coronary artery disease. The hemodilution (HD) group was hemodiluted before the bypass with dextran 70 (15 ml/kg; resulting mean hematocrit 32%) and further at the beginning of the bypass due to nonhemic priming of the oxygenator (mean hematocrit 15%). The control (C) group was not diluted before the bypass, and four units of red blood cells were included in the oxygenator priming (mean hematocrit 27% after the beginning of the bypass). The preoperative dilution produced a decline in the coronary sinus blood oxygen tension and oxygen saturation, but no change in the arterial-coronary sinus lactate balance. After the first 5 min of the bypass, the heart produced lactate in both the HD group and the C group, but the lactate production was more pronounced in the HD group. At the same time, the coronary sinus blood oxygen saturation was lower in the HD group than in the C group. Hypotension frequently accompanied the beginning of the bypass in both groups. It is concluded that the hemodilution to a hematocrit level of 32% in patients undergoing coronary revascularization for multiple stable coronary artery disease produces compensatory changes in myocardial oxygen extraction, but no changes of a generalized ischemia can be demonstrated. The hemodilution to a hematocrit level of 15% produces myocardial ischemia in patients with a normothermic unloaded heart, adding to the effect of hypotension at the beginning of the bypass.     

急性高容量血液稀释联合控制性降压对血液动力学及氧代谢的影响

目的 观察术中急性高容量血液稀释(AHH)联合硝普钠或尼卡地平控制性降压(CH)时血液动力学、氧代谢的变化,评价其可行性。方法 全麻手术病人30例,随机分为两组,每组15例。组Ⅰ AHH联合硝普钠CH;组ⅡAHH联合尼卡地平CH。手术开始后在30 min内输入15 ml·kg-1中分子羟乙基淀粉溶液。同时,以MAP基础值的70％为目标,行CH。分别于麻醉诱导后即AHH联合CH前(基础值,T0)、AHH联合CH后30min(T1)、60min(T2)记录血液动力学指标,同时采集中心静脉血、股动脉血测定血气及动脉血乳酸浓度(LAC),计算氧供(DO2)、氧耗(VO2)和氧摄取率(ERO2)。结果 与T0比较:两组Hb、Hct、MAP、SVR下降,HR增快(P<0.01),VO2、LAC无明显变化(P>0.05);组Ⅰ CO、CI、CVP均无明显变化(P>0.05),组Ⅱ上升(P<0.01);组Ⅰ ScvO2、DO2,显著性降低(P<0.01),组Ⅱ无明显变化(P>0.05);组Ⅰ ERO2增加(P<0.01),组Ⅱ无明显变化(P>0.05)。与组Ⅰ比较,组ⅡT0时各指标差异无显著性(P>0.05),T1、T2时CO、CI、CVP、ScvO2、DO2升高,而HR、SvR、ERO2降低(P<0.01)。结论 急性高容量血液稀释联合硝普钠或尼卡地平CH,能维持机体血液动力学和氧代谢的相对稳定,硝普钠减低容量负荷作用强于尼卡地平,而尼卡地平对机体氧代谢影响更小。     

急性高容血液稀释对老年心脏手术病人脑氧合功能的影响

目的　观察急性高容性血液稀释 (AHHD)对老年心脏手术病人脑氧合功能的影响并探讨其可能的作用机制。方法　 2 4例冠状动脉搭桥术 (CABG)的病人 ,ASAⅠ～Ⅱ级 ,随机分为老年扩容组、未扩容组和中青年扩容组。扩容组诱导时 1小时内经颈内静脉推注 6 %贺斯溶液 1 0ml/kg ,同时静注硝酸甘油 0 5μg·kg- 1 ·min- 1 。分别于术前、诱导后 5分钟、扩容止及主动脉插管时监测血液动力学指标 ,测定动、静脉血乳酸浓度 ,脑血氧饱和度 (SjvO2 ) ,脑血氧分压 (PjO2 )和脑血流速率。结果　 (1 )老年扩容组的PAP较术前显著增高 (P <0 0 5) ,但与其他两组相比无显著差异。 (2 )未扩容组的SjvO2 ,CBF/CMRO2 在主动脉插管时较术前显著降低 (P <0 0 1 ) ,与扩容组相比也显著减少 (P<0 0 5) ;而老年扩容组SjvO2 较术前及另外两组均显著增加 (P <0 0 5) ,CBF/CMRO2 无明显变化。(3)脑血流速率在中青年扩容组病人均显著高于另外两组 (P <0 0 5)。 (4)脑乳酸净生成量 (ADVL)三组间无显著差异 (P >0 0 5)。结论　AHHD对老年手术病人脑氧合功能具有一定的保护作用。     

非体外循环冠状动脉搭桥手术的麻醉方法及血液动力学和氧代谢的变化

目的 观察非体外循环冠状动脉搭桥手术的麻醉方法、术中病人血液动力学和氧代谢的变化以及术后病人的早期.非体外循环冠状动脉搭桥手术闰人20例，麻醉用咪唑安定0.1-0.2mg/kg、芬太尼15－30μg/kg及0.5%-2%的吸入麻醉药等，在切皮前、开心包后、心脏操作中、操作完成后10min及术毕观察血液动力学指标及脑氧饱和度，同时采集桡动脉和肺动脉血，测定血气及动脉血乳酸（ABL），计算氧供DO2）、氧耗（VO2）和氧摄取率（ERO2）。术后早期观察术后拔除气管插管、ICU停留及术后住院时间、并发症及死亡等情况。结果 心脏操作中MAP、SV、SI下降，HR、CVP升高，MAP下降以搭回旋支时最明显（P＜0.01），HR升高以搭右冠时最明显（P＜0.01）；心脏操作中DO2降低（P＜0.05），VO2无变化，ERO2升高（P＜0.01）；操作后DO2、ERO2恢复至操作前水平；操作后ABL升高（P＜0.01）。结论 本组麻醉方法使病人完全度过非体外循环搭桥术，在心脏操作期易出现血压、每搏量、心指数下降，伴心率、静脉压升高，但时间短暂无严重后果，氧代谢紊乱及缺氧程度较轻。     

非体外循环冠脉搭桥术中心脏移位对血液动力学的影响

目的 观察非体外循环冠脉搭桥术(OPCABG)中暴露术野时心脏位置改变对心血管功能的影响。方法 冠心病多支病变患者47例,年龄50～82岁,术前左室射血分数为0.55±0.14,择期行OPCABG,平均移植血管桥3.2条。采用漂浮导管方法监测血液动力学,分别在麻醉诱导后循环稳定时(T_1)、搬动心脏前(T_2)、吻合前降支时(T_3)、吻合右冠状动脉或后降支时(T_4)、吻合左旋支或对角支时(T_5)、血管吻合完成、心脏恢复自然位置后(T_6)、及手术结束时(T_7)作参数测定。结果 吻合前降支时(T_3),SI和LVSWI有所降低(P<0.01),但CI和SvO_2保持在基础水平。吻合后降支或右冠状动脉、左旋支或对角支时(T4、T5),CI、SI、LVWI、LVSWI、RVWI和RVSWI等明显降低(P<0.01),其中CI较对照值降低18％,LVWI和RVWI降低均为25％,MAP和SvO_2也显著下降(P<0.05～0.01),而HR、RAP、MPAP、PAWP和PVRI则显著增高(P<0.05～0.01)。心脏恢复自然位置后(T_6),CI、LVWI和RVWI恢复到对照值水平。结论 OPCABG术中由于心脏被搬动及移位,可导致明显的心功能损害和血压下降;麻醉手术期间采取可靠的血液动力学监测和有效的心血管功能支持十分必要。     

急性高容量血液稀释联合瑞芬太尼控制性降压对颅内动脉瘤术患者血流动力学和脑氧代谢的影响

目的 观察颅内动脉瘤夹闭术患者在急性高容量血液稀释(AHH)联合瑞芬太尼控制性降压(CH)后血流动力学和脑氧代谢的变化,评价其可行性.方法 选择颅内动脉瘤夹闭术患者40例,随机均分为硝酸甘油组(A组)和瑞芬太尼组(B组).手术开始时以15～20 ml·kg-1·h-1的速率输入4％琥珀酰明胶,使Hct稀释为25％～32％.在剪开硬脑膜后行CH,A组泵入硝酸甘油1～5 μg·kg-1 ·min-1;B组泵入瑞芬太尼12～30 μg·kg-1·h-1,使MAP维持在60～65 mm Hg,动脉瘤夹闭后10 min停止CH.记录两组患者AHH前(T0)、AHH后(T1)、降压前(T2)、降压后30 min(T3)、动脉瘤夹闭后5 min(T4)的MAP、HR、Hb和Hct,分别于T2～T4时采集颈内静脉球部血和桡动脉血作血气分析,检测动、静脉血氧饱和度(SaO2、SjvO2)、动、静脉血氧分压(PaO2、PjvO2)、Hb和Hct,计算动脉氧含量(CaO2)、颈内静脉氧含量(CjvO2)、动脉颈内静脉球部血氧差(Da-jvO2)、颈内静脉球部动脉乳酸差(VADL)和脑氧摄取率(CERO2).结果 与T0时比较,T1～T4时两组Hb和Hct均显著降低(P＜0.01).与T2时比较,T3、T4时两组MAP明显降低,A组HR明显增快,B组的HR明显减慢(P＜0.01);T3、T4时B组SjvO2和CjvO2明显高于T2时和A组,Da-jvO2和CERQ明显低于T2时和A组(P＜0.01).结论 AHH联合瑞芬太尼CH用于颅内动脉瘤夹闭术中,不但维持血流动力学的相对稳定,而且明显降低脑氧代谢率,较AHH联合硝酸甘油CH更具优越性.     

Pulmonary metabolism of endothelin 1 during on-pump and beating heart coronary artery bypass operations

BACKGROUND: Coronary artery bypass operations are associated with increased circulating levels of the powerful vasoconstrictor endothelin 1. The pulmonary circulation is an important site for both production and clearance of endothelin 1. Lung endothelial injury resulting from cardiopulmonary bypass could modify pulmonary endothelin 1 metabolism through an increase in production, a reduction in removal, or a combination of both. METHODS: Pulmonary endothelin 1 kinetics were quantified by using the indicator-dilution technique in patients undergoing coronary artery bypass grafting with (n = 11) or without cardiopulmonary bypass (ie, beating heart; n = 10). Mixed venous endothelin 1 levels were also measured in samples from the pulmonary artery, and systemic levels were obtained from the radial artery. RESULTS: Pulmonary artery endothelin 1 levels were similar before and after cardiopulmonary bypass, with means of 1.59 +/- 0.37 pg/mL and 1.33 +/- 0.15 pg/mL (P =.45), respectively. Systemic endothelin 1 levels, however, increased after bypass from 1.64 +/- 0.22 pg/mL to 2.07 +/- 0.16 pg/mL (P =.01). In the beating heart group, endothelin 1 levels before and after the operation were similar in the pulmonary artery (1.25 +/- 0.27 pg/mL and 1.45 +/- 0.31 pg/mL, respectively; P =.38), as well as in the radial artery (1.70 +/- 0.26 pg/mL and 1.73 +/- 0.35 pg/mL, respectively; P =.92). The capacity to clear endothelin 1 from the pulmonary circulation, as computed from the permeability-surface area product for endothelin 1, was not affected by cardiopulmonary bypass before and after the operation (25.19 +/- 2.67 mL/s and 23.12 +/- 4.39 mL/s, respectively; P =.49). It was similar and also unaffected in the beating heart group. CONCLUSION: Coronary artery bypass grafting with cardiopulmonary bypass is associated with an increase in systemic endothelin 1 levels. The mechanism involved is not related to a decreased pulmonary clearance of endothelin 1 from the systemic circulation but rather to an increased endothelin 1 release by the lungs.     

高容血液稀释联合控制性降压对腰椎手术病人血液动力学和氧代谢的影响

目的 探讨术前急性高容血液稀释联合术中控制性降压对腰椎手术病人血液动力学和氧代谢的影响。方法 择期行腰椎骨折椎板减压切开复位内固定术病人30例,随机分为二组:术前急性高容血液稀释联合术中控制性降压组(联合组)和单纯控制性降压组(对照组),每组15例。联合组术前输入6％羟乙基淀粉20 ml/kg和乳酸林格氏液20 ml/kg,行急性高容血液稀释;术中微量泵输注硝普钠0.5-6 μg·kg-1·min-1实施控制性降压,平均动脉压(MAP)控制在55-65 mm Hg;对照组术中控制性降压同联合组。观察联合组插管后稀释前即刻(T0)、稀释后降压前即刻(T1)、降压后30 min(T2)和停降压后30 min(T3)时,对照组插管后降压前即刻(T1)、降压后30 min(T2)和停降压后30 min(T3)时心率(HR)、MAP、中心静脉压(CVP)、心输出量(CO)、氧供(DO2)氧耗(VO2)以及动脉血乳酸(LA)的变化。结果 HR:联合组T1低于T0,对照组T2、T3高于T1,T3 低于 T2;联合组 T2、T3低于对照组。MAP:与T0比较,联合组T1、T3升高、T2降低;T2低于T1,T3高于T2;与T1比较,对照组T2降低、T3升高;与对照组比较,联合组T3降低。CVP:联合组T1高于T0,T2低于T1;对照组T2、T3低于T1;与对照组比较,联合组T1、T2升高。CO:联合组T1、T2高于T0,T3低于T2;联合组T1、T2高于对照组。D02:联合组T1、T3     

非体外循环冠脉搭桥术后病人静脉自控镇痛对血液动力学和氧代谢的影响

目的评价病人静脉自控镇痛(PCIA)对不停跳冠脉搭桥术后血液动力学和氧代谢的影响.方法 40例不停跳冠脉搭桥术后病人随机分为PCIA组和肌注镇痛组(IM组),每组20例.PCIA组镇痛药配方为吗啡100 mg、咪唑安定0.03～0.06 mg/kg和胃复安20 mg,用生理盐水稀释至100 ml.手术结束后开始镇痛,背景剂量1 ml/h,PCA量1 ml,锁定时间15 min.IM组病人诉疼痛时,肌肉注射哌替啶50 mg/次,间隔时间不少于6 h.术后进行VAS评分,保留Swan-Ganz导管,以Baxter CCO监测仪监测血液动力学及混合静脉血氧饱和度(SO2),并计算全身氧代谢指标.结果 (1) 术后16、24和40 h ,PCIA组VAS明显低于IM组(P＜0.05).(2) 术后随时间延长,CO和CI均渐增加,两组间差异无显著性.术后24 h和40 h ,PCIA组HR、MAP和SVR均明显低于IM组(P＜0.05).(3) 两组间DO2无差异.而PCIA组的VO2和O2 ER明显低于IM组(P＜0.01),SO2明显高于IM组(P＜0.05).结论病人静脉自控镇痛能为冠脉搭桥术后病人提供有效镇痛,减少血液动力学波动,同时改善全身氧供需平衡.     

老年病人冠脉搭桥术中脑氧代谢与术后精神障碍的关系

目的 观察老年病人体外循环(CPB)冠脉搭桥术(CABG)中脑氧代谢变化与术后精神障碍的关系。方法 年龄≥65岁择期CABG病人30例,取右颈内静脉和桡动脉血进行血气分析,葡萄糖及乳酸测定,并计算脑血流量/脑氧耗比值(CBF/CMRO_2)、脑氧耗/脑糖耗比值(CMRO_2/CMRglu)及乳酸生成量(ADVL);术后用ICU精神错乱评估量表(CAM-ICU)将病人分为精神障碍(POMD)组和无精神障碍(NPMD)组,比较两组术中指标差异。结果 (1)术后7例病人发生POMD,发生率为23.33％;(2)复温期8例病人颈内静脉血氧发生去饱和(颈内静脉血氧饱和度≤50％或颈内静脉血氧分压≤25mmHg),其中POMD组3例(发生率43％),NPMD组5例(发生率22％),两组差异显著(P<0.01);(3)复温期POMD组CBF/CMRO_2显著低于NPMD组(P<0.01);(4)降温期、复温期和停CPB,尤其是复温期,POMD组CMRO_2/CMRglc明显低于NPMD组,P<0.01,而ADVL明显高于后者(P<0.01)。结论老年病人CABG术后精神障碍与CPB期间脑氧代谢失衡有关。     

非体外循环冠状动脉旁路移植术后早期血流动力学和心肌损伤的观察

目的观察非体外循环冠状动脉旁路移植术（OPCAB）后早期血流动力学变化及心肌损伤。方法选择20例择期OPCAB患者,连续监测血流动力学变化,并记录麻醉诱导后10min（T0）、血运重建后30min（T1）、2h（T2）、6h（T3）、12h（T4）、24h（T5）的血流动力学参数,同时测定血浆肌酸激酶同功酶（CK-MB）、心肌肌钙蛋白1（cTnI）和N端B型脑钠肽（NT—proBNP）浓度。吻合血管前和血运重建后30min分别取右心房心肌组织透射电镜观察超微结构的变化。结果围术期SBP和DBP无明显变化,但血运重建后HR增快（P〈0．01）、CVP、肺动脉楔压（PCWP）、平均肺动脉压（MPAP）和心指数（cI）升高（P〈0．01）,而体循环阻力（SVR）、体循环阻力指数（SVRI）、每搏数（SV）、每搏指数（SVI）和左室每搏功指数（LVSWI）降低,右室每搏功指数（RVSWI）仅在血运重建后2h降低（P〈0．01）。CK-MB和cTnI从血运重建后持续升高（P〈0．05）,尤以血运重建后24h为明显。NT-proBNP在血运重建后12h内无显著变化,但在血运重建后24h显著升高（P〈0．01）。透射电镜下见血运重建后肌丝结构较术前模糊,线粒体有变形,结构不清晰,嵴模糊。结论OPCAB血运重建后早期存在心肌损伤和左右心功能下降,以左心为著。     

Effects of a bolus injection of adenosine triphosphate on atrioventricular conduction and hemodynamics in patients undergoing coronary artery bypass grafting

OBJECTIVE: To investigate the effects of adenosine triphosphate (ATP) on atrioventricular (A-V) conduction and hemodynamics in patients undergoing coronary artery surgery. DESIGN: A prospective study. SETTING: University teaching hospital. PARTICIPANTS: Patients scheduled for elective coronary artery bypass graft surgery. INTERVENTIONS: Anesthesia was induced with the same dose of intravenous fentanyl (300 microg) and midazolam (10 mg) for each patient. After the baseline measurement, a bolus dose of 10 mg of ATP (0.19+/-0.03 mg/kg, mean +/- SD) was rapidly injected through a central venous catheter. Right ventricular pacing was conducted at a rate of 40 beats/min during the development of complete A-V block. MEASUREMENTS AND MAIN RESULTS: ATP induced an A-V block in 10 of 12 patients (2:1 block in two patients and complete A-V block in eight patients). The onset of the A-V block was rapid (17.1+/-3.4 seconds) and the duration was short (12.1+/-7.0 seconds). Radial arterial pressure (AP) decreased with the appearance of the A-V block (p < 0.01). Heart rate (HR) returned to the baseline value quickly after the restoration of the A-V block, but recovery of radial AP was delayed. HR increased 1 minute after the ATP injection (p < 0.01). Both HR and radial AP returned to the baseline values 2 minutes after the ATP injection. ST segments on both leads II and V5 of electrocardiograms decreased more than 0.10 mV 1 minute after the ATP injection in one patient. CONCLUSION: A bolus injection of 10 mg of ATP successfully induced a transient A-V block in 83% of the 12 patients. The countermeasures, including ventricular pacing, are indispensable to cope with the subsequent hypotension that may lead to myocardial ischemia, especially in patients with ischemic heart disease.     

Effect of coexisting Paget's disease on coronary artery bypass operations

Paget's disease of the sternum is rare. In patients with sternal Paget's disease, sternotomy, and harvesting of internal mammary arteries may reveal problems because of a thickened sternum and substernal adhesions. Saphenous vein graft or other arterial grafts may be used. Especially in younger patients who received saphenous vein graft, a repeat revascularization operation, because of earlier saphenous vein graft degeneration, may be needed in subsequent years. During the repeat operation, opening and reclosing the chest will still be a major problem. In appropriate patients, an operation through a thoracotomy or noninvasive balloon and/or stent techniques may be good choices.     

丙泊酚对血液稀释时组织氧代谢的影响

目的　观察丙泊酚对急性等容血液稀释 (ANH)时组织氧代谢的影响。方法　择期手术病人 2 4例 ,随机分为三组 ,每组 8例 :A组为ANH组 ,P4组为ANH +丙泊酚 4mg组 ,P8组为ANH +丙泊酚 8mg组 ,三组病人ANH后Hct降至 2 7 1 %。漂浮导管放置完成后稳定 2 0min(T1 ) ,P4和P8组给予丙泊酚负荷剂量 2mg/kg后 ,分别给与丙泊酚维持剂量 (P4组 :4mg·kg-1 ·h-1 ;P8组 :8mg·kg-1 ·h-1 )。稳定 1 0min后 (T2 ) ,开始进行血液稀释。同时于T1 、T2 、T3 (血液稀释完成后1 5min)分别监测血液动力学指标和混合静脉血氧饱和度 (S vO2 ) ,血乳酸值 (T1 、T3 )。结果　三组病人ANH后均可见心排血量 (CO) ,每搏量 (SV)升高非常显著 ,外周血管阻力 (SVR)和动脉血氧含量(CaO2 )下降非常显著 ,氧供给 ( DO2 )、S vO2 及血乳酸改变不明显 ;P4和P8组SVR下降显著 ,MAP下降非常显著 ,组间比较无差异。结论　本实验剂量范围内 ,丙泊酚与ANH合用时 ,组织氧代谢水平未受明显影响     

Efficacy of off-pump coronary artery bypass grafting in patients requiring noncardiac operations]

Off-pump coronary artery bypass grafting was performed for patients with concomitant disease requiring noncardiac operations. Eight patients underwent CABG prior to or at the same time of noncardiac operation: lung cancer (2), gastric cancer (2), arteriosclerotic occlusive disease (2), abdominal aortic aneurysm (1), aorto-iliac occlusive disease (1). Of these, there were 6 patients who underwent off-pump CABG. Two patients underwent conventional CABG with extracorporeal circulation. Off-pump CABG was performed through a median sternotomy and small left thoracotomy. One patient received quadruple grafts, and another one received double, and 4 received single grafting. Simultaneous noncardiac operations were carried out in 3 patients (Y-grafting, femoro-femoral bypass, mediastinal lymphnode biopsy). The other 3 patients underwent subsequent operations (axillo-femoro-popliteal bypass, aorto-femoral bypass, subtotal gastrectomy). However, of the 2 patients with conventional CABG, 1 died of multiple metastasis after lobectomy of lung cancer that might have been affected by the extra-corporeal circulation. Off-pump CABG is efficient in patients with concomitant disease requiring noncardiac operations.     

Effects of cardiopulmonary bypass on sufentanil pharmacokinetics in patients undergoing coronary artery bypass surgery

BACKGROUND: Complete pharmacokinetic modeling, including assessment of the effect of cardiopulmonary bypass (CPB) on sufentanil disposition, has not been reported. The aims of this investigation were to define a model that accurately predicted sufentanil concentrations during and after cardiac surgery and to determine if CPB had a clinically significant impact on sufentanil pharmacokinetics. METHODS: Population pharmacokinetic modeling was applied to data from 21 patients undergoing coronary artery bypass grafting. The predictive ability of models was assessed by calculating bias, accuracy, and measured:predicted concentration ratios versus time. A simple three-compartment model, without covariates, was initially compared with models having weight or gender as covariates and was subsequently used as the foundation for multiple CPB-adjusted models (allowing step-changes of parameters at the start or end of CPB). The primary criterion for choosing more complex models was a significant improvement in log-likelihood; secondary criteria were significant improvement in bias or accuracy. RESULTS: Neither covariate (weight or gender) models improved bias or accuracy compared with the simple three-compartment model. A final CPB-adjusted model with V2 and Cl3 changing at the start of CPB and V1, Cl2, and Cl3 changing at the end of CPB had significantly greater log-likelihood values when compared with the simple three-compartment model and with less elaborate CPB-adjusted models. However, bias and accuracy for this final model were not significantly different from the simple three-compartment model. CONCLUSIONS: When sufentanil is infused at a constant rate, with initiation of CPB, a pharmacokinetic model adjusted for CPB predicts that the sufentanil concentration will decrease approximately 17% and that it will begin to return to the prebypass concentration 12 min after initiation of CPB. At the end of CPB, this model also predicts a brief spike of the sufentanil concentration. These predictions reflect changes in the measured sufentanil concentrations. However, compared with a simple, three-compartment model, incorporating step-changes of pharmacokinetic parameters at the start or end of cardiopulmonary bypass (or both) did not significantly improve overall perioperative prediction of measured sufentanil concentrations. This suggests that CPB has clinically insignificant effects on sufentanil kinetics in adults.