Cerebral perfusion

Aortic arch surgery necessitates interrupted brain perfusion and carries a risk of brain injury. Various brain protective techniques have been advocated to reduce risk including hypothermic arrest and retrograde or selective antegrade perfusion. Knowledge of the pathophysiologic consequences of deep hypothermia, may aid the surgeon in deciding when to initiate circulatory arrest and for how long. Retrograde cerebral perfusion use was advocated to prolong safe arrest durations but may not improve outcomes. Selective antegrade cerebral perfusion appears to have become the preferred method of brain protection. However, the delivery conditions and optimal perfusate constitution require further study.     

肝脏体外灌流中直接灌流与间接灌流效果的比较研究

目的在体外肝脏灌流（ECLP）实施技术研究中，对直接灌流和间接灌流孰优孰劣一直存在争议。本实验拟就临床应用对这两种方法进行评价。方法实验动物供体均为普通健康长白猪，体重在20～30kg，雌雄不拘。一组受体是普通健康长白猪，标准与供体相同；另一组受体是普通健康狗，体重在20～30kg，雌雄不拘。随机分为2组，直接灌流受体为肝衰猪，间接灌流受体为肝衰狗：A组（直接灌流组，n=5）体外肝脏与受体间直接进行血液交换；B组（间接灌流组，72-4）体外肝脏用猪血液进行ECLP循环，受体血液自循环，两个循环间的血液通过中空纤维管进行物质交换。A、B两组进行ECLP灌流时间均为4h，肝衰时间为8h，8h后处死。观察体外肝脏和受体一般情况，体外肝脏的胆汁生成量、耗氧率等，受体的血氨、肝脏酶谱和血凝情况等指标。结果A、B两组在体外肝脏的胆汁生成量、耗氧率和受体方面均没有明显的差异（P〉0．05）。结论虽然直接灌注和间接灌注两者在体外肝脏的存活和灌注效果方面没有明显的差异，但考虑到间接灌注在异种灌注中具有伦理学压力较小的诸多优点，而临床应用又以异种灌注为主，故临床应用时仍推荐应用间接灌注。     

CAPS--coronary-assisted perfusion system

For the past 35 years the use of the extracorporeal bypass circuit has been a mainstay for coronary artery bypass grafting (CABG) in cardiac surgery arena. Since John Gibbon's early design, evolution of the pump has expanded rapidly with new techniques and engineering. The cardiopulmonary bypass (CPB) circuit has allowed cardiovascular surgeons to perform complete revascularization in a motionless and bloodless field. Presently, there is a new focus on CABGs because of new engineering designs of retractors and stabilizers, robotic techniques, and the monetary issues of cost and length of stay. Surgeons at our hospital perform 70% of CABG procedures off pump. We have developed a coronary-assisted perfusion system called CAPS. This is a simple shunt system that uses existing pump hardware to deliver arterial blood to the myocardium after the completion of the distal anastomosis. Flow is regulated by monitoring a pressure-sensing display either at systemic or suprasystemic pressure. Temperature of the blood is maintained with a Vanguard BCD heat exchanger (COBE Cardiovascular Inc., Arvada, CO) with a built-in temperature probe port. This system is capable of delivering optional agents for coronary vasodilatation, myocardial resuscitation, and performance through a connection to any standard medication infusion pump. The advantages of this system are that it is safe, requires no additional perfusion hardware, cost effective, easy to setup, has a low and rapid prime, has both inflow and outflow pressure monitoring sites, has heat a exchanger with temperature monitor, and has a drug additive port for pharmacologic infusion.     

Monitoring tissue perfusion

Canadian Journal of Anesthesia/Journal canadien d'anesthésie - Despite these drawbacks, blood lactate concentrations can provide a valuable guide to tissue hypoxia and levels &;gt; 1.5...     

运用CT灌注成像监测介入断流术后肝脏血流灌注的变化

目的运用CT灌注成像评价肝硬化门静脉高压症患者介入断流术后肝脏血流灌注的变化。方法收集2001年6月至2006年5月间23例肝硬化门静脉高压症患者,其中15例行部分脾栓塞术、8例行部分脾栓塞术联合胃冠状静脉栓塞术;术前后采用东芝Xpress型螺旋CT行单层肝脏动态增强扫描,同时测定主动脉、门静脉和肝脏感兴趣区的CT值,取增强的CT值绘制时间密度曲线。去卷积法计算肝脏各灌注参数。结果部分脾栓塞术后肝脏门静脉灌注量有所减少,但肝动脉灌注量增加,总肝灌注量与术前差异无统计学意义（t＝-0．677,P〉0．05）,肝动脉灌注指数从12．5％升至32．5％。部分脾栓塞术联合胃冠状静脉栓塞术术前肝脏门静脉灌注量为0．862ml·min^-1·ml^-1,术后为0．722ml·min^-1·m^-1,两者差异无统计学意义（t=-0．281,P〉0．05）,肝动脉灌注量、总肝灌注量分别由术前的0．128、0．990ml·min^-1·ml^-1。增加至术后的0．290、1．021ml·min^-1·ml^-1。结论螺旋CT灌注成像能客观反映肝硬化门静脉高压症患者部分脾栓塞术、胃冠状静脉栓塞术术后肝血流动力学的变化。     

Acute perfusion changes after spontaneous SAH: a perfusion CT study

Background  

Perfusion computed tomography (CT) is a rapid technique that allows the measurement of acute disturbances in local and global cerebral blood flow in patients suffering stroke and spontaneous subarachnoid haemorrhage (SAH). The purpose of this study was to establish the relationship between different measures of brain perfusion made on dynamic-contrast CT reconstructions performed as soon as SAH has been diagnosed and the severity of the bleeding determined by the clinical grade, the extent of the bleeding and the outcome of the patients.     

Distributed perfusion educational model: a shift in perfusion economic realities

In recent years, a steady decline in the number of perfusion education programs in the United States has been noted. At the same time, there has been a parallel decline in the number of students graduated from perfusion educational programs in the United States. Also, as noted by several authors, there has been an increase in demand for perfusion graduates. The decline in programs and graduates has also been noted in anesthesia and surgical residency programs. The shift is caused by a combination of economic and clinical factors. First, decreased reimbursement has led to reallocation of hospital resources. Second, the original enthusiasm for beating heart coronary artery bypass surgery was grossly overestimated and has led to further reallocation of hospital resources and denigration of cardiopulmonary bypass. This paper describes two models of perfusion education programs: serial perfusion education model (SPEM) and the distributed perfusion education model (DPEM). Arguments are presented that the SPEM has some serious limitations and challenges for long-term economic survival. The authors feel the DPEM along with dependence on tuition funding can survive the current clinical and economic conditions and allow the profession to adapt to changes in scope of practice.     

Artificial perfusion in impotence

The physiology of normal erection is contrasted to that induced by artificial perfusion. The diagnostic value of the procedure is limited. Perfusion may be useful in monitoring the effect of drugs instilled into the penis or in choice of procedure.