Idu M M, Heintjes R J, Scholten E W, Balm R, de Mol B A J M, Legemate D A
Department of Vascular Surgery, Academic Medical Center, Amsterdam, The Netherlands.
Eur J Vasc Endovasc Surg. 2004 Feb;27(2):138-44. doi: 10.1016/j.ejvs.2003.11.009.
Left-heart bypass (LHB) and selective organ perfusion (SOP) are used during thoracoabdominal aortic surgery to prevent ischemic damage to the kidneys and visceral organs after supraceliac aortic crossclamping. We studied the hypothesis, in a porcine model, that despite LHB and maximal SOP, visceral and renal ischemia still occurred during surgery.
Eleven pigs (54-70 kg) were coupled to a non-pulsatile LHB with inflow and outflow at the lower thoracic and distal infrarenal aorta, respectively. After supracoeliac and infrarenal aortic crossclamping, SOP was started using perfusion catheters. The proximal and distal mean aortic blood pressures were kept above 70 and 50 mmHg, respectively, while the mean blood pressure within the SOP system was above 60 mmHg. The visceral and renal tissue oxygenation was measured by intermittent blood gas analysis, from the portal and both renal veins. The jejunal mucosal oxygenation was measured by tonometric measurement of the luminal pCO2.
Measured median blood blood flow through the LHB and the SOP system were 800 and 1140 ml/min, respectively. Median blood flow prior to, and during LHB and SOP through the celiac artery, superior mesenteric artery, and left renal artery were 300 and 240, 762 and 295, and 235 and 235 ml/min, respectively. During 3 h of LHB and SOP no significant changes in the renal tissue oxygenation were noted compared with the physiological situation prior to supracoeliac aortic crossclamping and cannulation. However, in the visceral vascular bed median mixed venous oxygen saturation dropped from 79 to 63% (p<0.001), and median oxygen extraction ratio increased from 26 to 41% (p<0.001). Median tonometric measured intraluminal jejunal pCO2 increased from 9.9 to 12.15 kPa (p>0.05). During 3 h of LHB and SOP no hemolysis was detected, as there was no rise in serum LDH.
LHB and SOP preserves renal but not visceral tissue oxygenation during supraceliac aortic crossclamping and does not induce hemolysis.
胸腹主动脉手术期间采用左心转流（LHB）和选择性器官灌注（SOP）来预防腹腔干上方主动脉交叉钳夹后肾脏和内脏器官的缺血性损伤。我们在猪模型中研究了以下假设：尽管采用了LHB和最大程度的SOP，但手术期间仍会发生内脏和肾脏缺血。
11头猪（体重54 - 70千克）连接至非搏动性LHB，分别在胸下部和肾下主动脉远端进行流入和流出。在腹腔干上方和肾下主动脉交叉钳夹后，使用灌注导管开始SOP。近端和远端平均主动脉血压分别维持在70 mmHg和50 mmHg以上，而SOP系统内的平均血压维持在60 mmHg以上。通过间歇性血气分析，从门静脉和双侧肾静脉测量内脏和肾脏组织氧合。通过对肠腔内pCO2进行张力测定来测量空肠黏膜氧合。
经测量，通过LHB和SOP系统的中位血流量分别为800和1140毫升/分钟。在LHB和SOP之前以及期间，通过腹腔干动脉、肠系膜上动脉和左肾动脉的中位血流量分别为300和240、762和295、235和235毫升/分钟。在LHB和SOP的3小时期间，与腹腔干上方主动脉交叉钳夹和插管前的生理状态相比，未观察到肾脏组织氧合有显著变化。然而，在内脏血管床，中位混合静脉血氧饱和度从79%降至63%（p<0.001），中位氧摄取率从26%增至41%（p<0.001）。中位张力测定的肠腔内空肠pCO2从9.9 kPa增至12.15 kPa（p>0.05）。在LHB和SOP的3小时期间未检测到溶血，因为血清乳酸脱氢酶没有升高。
在腹腔干上方主动脉交叉钳夹期间，LHB和SOP可维持肾脏组织氧合，但不能维持内脏组织氧合，且不会诱导溶血。
