体外膜肺氧合对急性右心衰竭犬血流动力学的影响

Effects of extracorporeal membrane oxygenation on hemodynamics in acute right heart failure in dogs

目的探讨体外膜肺氧合（ECMO）对急性右心衰竭犬血流动力学的影响。方法体重20～25kg健康成年雄性犬10只，按随机数字表法分为急性右心衰竭模型组和ECMO治疗组，每组5只。犬麻醉后行胸廓切开术，于右心房、右心室、肺动脉放置相关测压导管，测量右心房压（RAP）、右心室压（RVP）及肺动脉压（PAP）；于主动脉及肺动脉放置血管超声探头，测量心排血量（c0）及肺动脉流量（QPA），测得结果为基础值。ECMO组建立静脉一动脉体外膜肺氧合（VA—ECMO）转流，分别经股动脉和股静脉建立动、静脉插管，随后连接预充的ECMO装置。两组均逐渐套扎肺动脉以使QPA分别降至基础值的60％、40％和0％，每降至一个程度保持30rain，并测量上述血流动力学指标，观察其变化。结果模型组与ECMO组血流动力学指标基础值比较无明显差异。套扎肺动脉后，模型组CO（L／rain）于QPA降至60％和40％时均较基础值明显下降（1．80±0．19、1．48±0．22比3．24±0．23，均P〈O．05），且显著低于ECMO组（60~QPA：1．80±0．19比3．24±0．35；40％QPA：1．48±0．22比3．20±0．37，均P〈O．05）；ECMO组CO于QPA降至60％、40％和0％时与基础值比较差异无统计学意义（3．24±0．35、3．20±0．37、3．12±0．28比3．44±0．32，均P〉O．05）。模型组PAP、RAP和RVP（均irlmHg，1mmHg=O．133kPa）于QPA降至60％和40％时均较基础值明显增加（PAP：36．2±5．3、39．8±5．4比17．4±2．7；RAP：11．2±2．8、12．8±2．6比4．4±1．7；RVP：25．6±4．9、27．8±4．5比11．6±1．8，均P〈O．05），且显著高于ECM0组（60％QPA：PAP36．2±5-3比23．2±5．2，RAP11．2±2．8比6．2±2．3，RVP25．6±4．9比15．2±3．5；40~QPA：PAP39．8±5．4比24．4±4．8，RAP12_8±2．6比7．0±2．4，RVP27．8±4．5比16．8±4．2，均P〈O．05）；而平均动脉压（MAP，mmHg）较基础值明显下降（81．2±15．8、62．2±14．4比128．6±16．4，均P〈O．05），且显著低于ECMO组（60~QpA：81．2±15．8比128．0±26．5；40％QpA：62．2±14．4比124．6±25．4，均P〈O．05）。ECM0组心率（HR，次／rain）、PAP、RAP和RVP于QPA降至60％、40％和0％时均较基础值略有增加（HR：161．4±14．8、160．6±13．1、157．6±11．9比152．6±14．5：PAP：23．2±5．2、24．4±4．8、25．2±6．2比18．8±3．4；RAP：6．2±2．3、7．0±2．4、7．6±4．2比4．6±1．5；RVP：15．2±3．5、16．8±4．2、16．2±3．3比12．2±2．3），MAP贝0略有下降（128．0±26．5、124．6±25．4、121．2±21．4比135．8±22．2），但差异均无统计学意义（均P〉0．05）。结论VA—ECMO可以有效改善急性右心衰竭犬的心功能，并保持血流动力学稳定。

Objective To investigate the effects of extracorporeal membrane oxygenation （ECMO） on the hemodynamics in dogs with acute fight heart failure. Methods Ten healthy adult male dogs （weighted 20-25 kg） were randomly divided into two groups： acute right heart failure group （n=-5 ） and ECMO group （n = 5 ）. Under anesthesia, dogs were underwent thoracotomy, then the catheters were placed in the right atrium, right ventricle, and pulmonary artery, for measuring the relevant pressures, including fight arterial pressure （RAP）, right ventrieular pressure （RVP）, and pulmonary artery pressure （PAP）. The vascular ultrasound probe were placed on the aorta and pulmonary artery for measuring the cardiac output （ CO ） and pulmonary artery flow rate （ QPA ）. Then, a baseline measurement was acquired. The femoral artery and femoral vein were eannulated and used for the venoarterial extracorporeal membrane oxygenation （VA-ECMO）, and then connected to extracorporeal circuit, which was initially primed. The pulmonary artery was progressively ligated to decrease blood flow until QPA was 60%, 40%, and 0% of baseline in both groups. The above flow conditions were respectively maintained for 30 minutes, after which hemodynamic data were collected. Results The baseline hemodynamic measurements were not different between acute right heart failure group and ECMOgroup. After ligating the pulmonary artery, compared with baseline, CO （L/min） decreased significantly at 60% and 40% QPA in acute right heart failure group （1.80 ±0.19, 1.48 ±0.22 vs. 3.24 ±0.23, both P〈0.05）, and significantly lower than that of ECMO group （60%QPA： 1.80 ± 0.19 vs. 3.24 ± 0.35; 40%QPA： 1.48 ± 0.22 vs. 3.20 ± 0.37, both P〈0.05 ）. CO was not significantly different from baseline in ECMO group at 60%, 40% and 0% QPA （3.24 ± 0.35, 3.20 ± 0.37, 3.12 ± 0.28 vs. 3.44 ± 0.32, all P〉0.05 ）. PAP, RAP and RVP （all mm Hg, 1 mm Hg= 0.133 kPa） were significantly elevated in acute right heart failure group at 60% and 40% QPA compared with baseline （PAP： 36.2±5.3, 39.8± 5.4 vs. 17.4±2.7; RAP： 11.2±2.8, 12.8±2.6 vs. 4.4± 1.7; RVP： 25.6_±4.9, 27.8±4.5 vs. 11.6± 1.8, all P〈0.05 ）, and significantly higher than those of ECMO group （60%QPA ： PAP 36.2 ± 5.3 vs. 23.2 ± 5.2, RAP 11.2 ± 2.8 vs. 6.2± 2.3, RVP 25.6 ± 4.9 vs. 15.2 ± 3.5 ; 40%QPA ： PAP 39.8 ± 5.4 vs. 24.4 ± 4.8, RAP 12.8 ± 2.6 vs. 7.0 ± 2.4, RVP 27.8 ± 4.5 vs. 16.8± 4.2, all P〈0.05）, whereas mean artery pressure （MAP, mm Hg） was significantly lowered compared with that of baseline （81.2 _± 15.8, 62.2± 14.4 vs. 128.6 ± 16.4, both P〈0.05）, and it was lower than that of ECMO group （60%QPA： 81.2 - 15.8 vs. 128.0 ± 26.5; 40%QPA： 62.2 ± 14.4 vs. 124.6 ± 25.4, both P〈0.05）. At 60%, 40% and 0% QPA in ECMO group, whereas heart rate （HR, beats/min）, PAP, RAP and RVP were slightly increased compared with those of baseline （HR： 161.4 ± 14.8, 160.6 - 13.1, 157.6 - 11.9 vs. 152.6± 14.5; PAP： 23.2±5.2, 24.4±4.8, 25.2± 6.2 vs. 18.8±3.4; RAP： 6.2±2.3, 7.0±2.4, 7.6±4.2 vs. 4.6± 1.5; RVP： 15.2 ± 3.5, 16.8 ± 4.2, 16.2 ± 3.3 vs. 12.2 ± 2.3）, but MAP was slightly decreased （ 128.0 ± 26.5, 124.6 ± 25.4, 121.2 ±21.4 vs. 135.8 ±22.2）, however, all differences were not statistically significant （all P〉0.05）. Conclusion These findings demonstrate that VA-ECMO could be helpful in improving cardiac function, and maintaining stability of hemodynamics in dogs with acute right heart failure.