Dalton J M, Gore D C, Makhoul R G, Fisher M R, DeMaria E J
Department of Surgery, Medical College of Virginia, Richmond 23298-0475.
Crit Care Med. 1995 Mar;23(3):491-7. doi: 10.1097/00003246-199503000-00013.
To quantitate duplex Doppler measurements of splanchnic perfusion to determine if these measurements are reproducible in euvolemic humans and if such measurements are sensitive to mild degrees of systemic hypovolemia.
Prospective, nonrandomized, controlled trial.
Clinical research center.
Seven fasting, healthy male and female volunteers, ranging in age from 25 to 37 yrs and weighing 60 to 90 kg.
Pulse, blood pressure, hematocrit, and duplex Doppler measurements of the peak systolic velocity and time averaged velocity of the subdiaphragmatic aorta, celiac artery, and superior mesenteric artery were obtained at four time points. Time points I and II were on separate days before hemorrhage and consisted of routine blood donation of 450 mL. Time point III was immediately after blood donation. Time point IV was 24 hrs after donation. Estimated blood flow was calculated from time averaged velocity (estimated blood flow = 60[vessel cross-sectional area][time averaged velocity]).
Vital signs and hematocrit remained without significant change at all time points. Peak systolic velocity, time averaged velocity, and estimated blood flow were also unchanged between measurements at time points I and II. However, after a mean reduction of 9.1% of total blood volume, duplex ultrasound detected significant decreases of 14.5% in celiac artery and superior mesenteric artery peak systolic velocity, as well as 15.1%, 17.3%, and 20.2% decreases in aorta, celiac artery and superior mesenteric artery time averaged velocity and estimated blood flow, respectively (all values p < .05 vs. baseline, Duncan's multiple range test). All measured variables returned to baseline 24 hrs after hemorrhage.
Noninvasive duplex Doppler measurements of splanchnic peak systolic velocity, time averaged velocity, and estimated blood flow are reproducible and sensitive to small changes in intravascular volume. These data suggest a potential clinical role for duplex imaging in the treatment of critically ill patients to guide therapy to optimize splanchnic perfusion.
对内脏灌注进行双功多普勒测量定量，以确定这些测量在血容量正常的人体中是否可重复，以及此类测量对轻度全身性血容量不足是否敏感。
前瞻性、非随机、对照试验。
临床研究中心。
7名空腹健康男性和女性志愿者，年龄在25至37岁之间，体重60至90千克。
在四个时间点获取脉搏、血压、血细胞比容，以及膈下主动脉、腹腔动脉和肠系膜上动脉的收缩期峰值速度和时间平均速度的双功多普勒测量值。时间点I和II在出血前的不同日期，包括常规捐献450毫升血液。时间点III在献血后立即进行。时间点IV在献血后24小时。根据时间平均速度计算估计血流量（估计血流量 = 60[血管横截面积][时间平均速度]）。
所有时间点的生命体征和血细胞比容均无显著变化。时间点I和II测量之间的收缩期峰值速度、时间平均速度和估计血流量也未改变。然而，在平均减少9.1%的总血容量后，双功超声检测到腹腔动脉和肠系膜上动脉收缩期峰值速度显著降低14.5%，以及主动脉、腹腔动脉和肠系膜上动脉的时间平均速度和估计血流量分别降低15.1%、17.3%和20.2%（所有值与基线相比p <.05，邓肯多重极差检验）。所有测量变量在出血后24小时恢复至基线水平。
对内脏收缩期峰值速度、时间平均速度和估计血流量进行无创双功多普勒测量是可重复的，并且对血管内容量的微小变化敏感。这些数据表明双功成像在危重病患者治疗中指导优化内脏灌注治疗方面具有潜在的临床作用。
