经食管多普勒超声监护系统在烧伤治疗中的应用

The use of transesophageal echo-Doppler device in the management of burns

目的 探讨大面积烧伤休克期应用经食管多普勒超声监护系统监测血流动力学指标变化并指导液体复苏的可行性。方法 （1）致家犬50％TBSA Ⅲ度烧伤，分别于伤前及伤后各时相点测量以下指标：Swan-Ganz漂浮导管热稀释法测定心排血量（CO）；经食管多普勒超声监护系统测定心率、主动脉血流量（ABF）、每搏输出量、左心室射血时间（LVET）、左心室峰值流速（PV）、左心室血流最大加速度（ACC）和外周血管阻力（TSVR）。（2）选择10例大面积烧伤患者，采用经食管多普勒超声监护系统于伤后24h内测定上述各项血流动力学指标。结果烧伤犬在无治疗情况下，CO与ABF均持续下降，二者间呈显著正相关（r=0．90，P〈0．01）；伤后心肌收缩力指标ACC、PV和心室前负荷指标LVET持续下降，后负荷指标TSVR则明显增加。接受治疗的临床患者，表现出自身的血流动力学指标变化规律，由早期的“低排高阻型”转变为伤后24h的“高排低阻型”。结论 经食管多普勒超声监护系统用于大面积烧伤后血流动力学监测，具有无创、连续、快速、同步的特点，能提供“全景式”的血流动力学数据及变化趋势，达到优化输液管理的目的。

Objective To investigate the validity of transesophageal echo-Doppler technique for hemodynamic monitoring of patients with extensive burns during shock stage to provide guidance for fluid resuscitation. Methods Mongrel dogs were inflicted with 50% TBSA full-thickness burns. Cardiac output （CO） were determined by Swan-Ganz catheter, and other hemodynamic indices by transesophageal echo-Doppler device, including aortic blood flow （ABF）, stroke volume （SVa）, left ventricle ejection time （LVET） , peak velocity （PV）, max acceleration （max ACC）, total systemic vascular resistance （TSVR） were collected before and after burns. Hemodynamic indices of ten patients with extensive burns were collected by transesophageal echo-Doppler device with in 24 hours after the injury. Results Both CO and ABF showed continuous decrease after burns, and there was positive correlation between them （ r = 0.90, P 〈 0. 01 ）. The myocardiac contractibility （ACC,PV） and the preload of the left ventricle （LVET） were also decreased continuously after burns,but the postburn afterload （TSVR） were obviously increased. For the patients with conventional therapy, the hemodynamic state of low cardiac output and high peripheral resistance during early period was converted to high cardiac output and low peripheral resistance 24 hours after injury. Conclusion Transesophageal echo-Doppler technique is useful in monitoring hemodynamic in patients with extensive burn, and it is non-invasive, real-time,synchronized and rapid, and it can provide complete profile of hemodynamic data.