去甲肾上腺素对脓毒性休克心排出量的影响及相关因素分析

The effects of Early Administration of Norepinephrine on Cardiac Preload and Contraction in Septic Shock Patients

目的探讨早期应用去甲肾上腺素对脓毒性休克患者心排出量的影响以及各因素之间的相关性。方法采用前瞻性观察研究的方法,对2012年9月至2012年11月南京大学医学院附属鼓楼医院重症医学科收治的36例脓毒性休克患者,给予或增加去甲肾上腺素静脉泵入维持平均动脉压(MAP)≥65 mm Hg。采用脉搏轮廓连续心排出量监测(PiCCO)法监测患者心率(HR)、MAP、中心静脉压(CVP)、心排指数(CI)、每搏排出量指数(SVI)、外周血管阻力指数(SVRI)、血管外肺水指数(EVLWI)、全心舒张末期容积指数(GEDVI)和心功能指数(CFI)等血流动力学指标。观察应用去甲肾上腺素治疗(给予或增加去甲肾上腺素)前后血流动力学的变化。结果脓毒性休克患者应用去甲肾上腺素治疗后血流动力学监测结果显示:CI和SVI显著增加[(4.08±1.18)比(3.50±1.10)L·min-1·m-2,(35.98±9.93)比(30.45±8.64)mL/m2,均P<0.05],CVP和GEDVI亦显著增加[(8.61±2.91)比(8.17±2.73)mm Hg,(762.22±143.83)比(700.44±137.90)mL/m2,均P<0.05),CFI显著增加[(5.62±2.24)比(5.25±2.29)L/min,P<0.05],MAP和SVRI明显升高[(77.72±8.22)比(60.17±4.26)mm Hg,(1469.33±471.35)比(1289.44±397.30)dyn·s·cm-5·m-2,均P<0.05],HR无明显改变[(114.50±17.98)比(113.94±17.21)次/min,P>0.05]。动脉血乳酸较治疗前显著降低[(3.23±3.92)比(4.46±4.67)mmol/L,P<0.05]。去甲肾上腺素治疗前后GEDVI变化(ΔGEDVI)、CFI变化(ΔCFI)与CI变化百分比(ΔCI%)呈显著正相关(r值分别为0.74和0.92,均P<0.05),而治疗前GEDVI、CFI则与ΔCI%无明显相关性(均P>0.05)。结论脓毒性休克早期应用去甲肾上腺素可以增加患者心排出量,与去甲肾上腺素增加心脏前负荷以及心肌收缩力有关。

Objective To assess the effects of early administration of norepinephrine on cardiac output and relevant factors in septic shock patients. Methods 36 septic shock patients were enrolled from intensive care unit of Nanjing Drum Tower Hospital from September to November 2012. All patients received norepinephrine early to maintainthe mean arterial pressure （MAP） ≥65 mm Hg. The changes of heart rate （HR） , MAP, central venous pressure （ CVP）, cardiac index （ CI）, stroke volume index （ SVI ）, index of systemic vascular resistance （ SVRI）, extravascular lung water index （ EVLEWI）, global end-diastolic volume index （GEDVI）, cardiac function index （CFI） in transpulmonary thermodilution variables associated with the increase of MAP induced by norepinephrine when achieved MAP ≥ 65 mm Hg were monitored. Results Norepinephrine significantly increased CI and SVI（4. 08± 1.18 vs. 3.50 ±1.10 L · min^-1· m^-2 ,35.98 ± 9. 93 vs. 30. 45 ±8. 64 mL/m^2 , both P 〈 0. 05 ）. Norepinephrine also significantly increased CVP and GEDVI（8.61 ±2.91 vs. 8. 17 ±2.73 mm Hg,766. 00 ± 164.27 vs. 700.44 ± 137.90 mL/m^2,both P〈 0. 05 ）, CFI （5.66 ±2. 35 vs. 5.25±2.29 L/min, P 〈0. 05） ,MAP and SVRI（77.72±8.22 vs. 60.17 ± 4. 26 mm Hg, 1469. 33± 471.35 vs. 1289.44 ± 397. 30 dyn · s ·cm^-5 · m^-2,both P 〈 0. 05 ）. No change in HR（ 114. 50 ± 17. 98 vs. 113. 94 ± 17. 21 beats/min, P 〉 0. 05 ） was observed. Arterial blood lactate significantly decreased （3.23 ±3.92 vs. 4. 46 ±4. 67 mmol/L,P 〈0. 05）. There was significant correlation between ΔGEDVI, ΔCFI and ΔCI% （ r values were 0.74 and 0. 92, both P 〈 0. 05 ）. There was no significant correlation between baseline GEDVI, CFI and ΔCI% （ both P 〉 0. 05 ）. Conclusion Early administration of norepinephrine in septic shock patients is able to increase cardiac output which may be ascribed to increased cardiac nreload and cardiac contractilitv.