Перевод "Cryoprotective Perfusion"

Cryoprotective Perfusion

Cryoprotective perfusion poses difficult and costly problems to solve. However, some potential time and money saving short-cuts do exist and will be discussed later. The first thing to consider is what is required. A CPA system capable of loading a patient with concentrations of cryoprotectant needed to allow for vitrification (CNV) must incorporate many of the functional and safety features of a standard extracorporeal circuit. It must have pumps to deliver flow and recover perfusate leaking from wounds and return it to the circuit (or in the case of isolated cephalon perfusion, to recover the venous effluent in its entirety and return it to the recirculating reservoir). In the past these pumps have not been automated and data collection has been manual. This has lead to delayed understanding of important phenomenon such as the mechanism of increasing burr hole leakage during whole body perfusions. It also is a potential source of error and injury to patients. Pumps in the CPA circuit should be automated and, even if under manual control, should feed data directly to a computer for conversion to real time graphic data.

Typical computerized data acquisition and control set-up (above).

All physiologic and circuit pressures must have real-time data acquisition and display as well as alarm features with color separation of each critical temperature displayed. This is important not only for physiological pressures such as arterial, central venous, and intracranial pressure, but also for filter back-pressures which have been allowed to reach dangerous levels (in excess of 30 psi) routinely in the past.

Similarly, CPA and recirculating reservoir volumes must be continuously monitored and alarmed to prevent pumping the recirculating reservoir dry and thus pumping air to the patient, as well as to prevent inadvertent loss of perfusate if there is a leak in the circuit, or a critical clamp has been inappropriately applied (or not applied) when and where it should have been. Again, this data should be continuously acquired, and alarms should be audible and distinctive (insofar as this is technically feasible) for each critical parameter being monitored.