Depressed Metabolism

One of the most neglected aspects of cryonics is that its procedures, and the research to support them, can have important practical applications in mainstream fields such as organ preservation and emergency medicine. Contrary to popular opinion, cryonics does not just involve an optimistic extrapolation of existing science but can set the standard for these [...]

An important objective during stabilization of cryonics patients is restoring circulation of blood to the brain. In ideal cases, this can be achieved by aggressive mechanical cardiopulmonary support, hemodilution ,and administration of vasoactive medications. In not-so-ideal cases, one or more of these interventions are omitted or delayed. This raises the question if low flow perfusion [...]

It is difficult to match concerns about reperfusion injury during cardiopulmonary resuscitation (CPR) with specific proposals for alternative interventions. After all, no matter how harmful the effects of oxygenation may be, not restoring circulation in a patient in cardiac arrest is hardly a credible option. One alternative would be to restore circulation but withhold oxygen [...]

One concern about prolonged cardiopulmonary support in cryonics is that its decreasing effectiveness may not be able to meet cerebral oxygen demand, and may even become detrimental. Some investigators have  observed that severely reduced flow (cerebral blood flow less than 10% of control) to the brain may actually be more harmful than no flow at all.  Explanations [...]

As discussed in a previous post, perfusion of the brain following long-term (>5 min) ischemia has been shown to be significantly compromised, particularly in subcortical regions. An interesting recent article by Ristagno, et. al in Resuscitation (May 2008) has added new data to the equation, using some of the most advanced technologies available for measuring [...]

Conventional CPR typically generates around one-third to one-fourth of normal cardiac output, which is not sufficient to meet cerebral energy demands. In cryonics patients, cardiac output may be further compromised because many patients are atherosclerotic and/or have gone through a prolonged period of shock / multiple organ failure prior to pronouncement of legal death. However, [...]

The best non-invasive indicator of cardiac output and oxygenation during cardiopulmonary support (CPS) is end tidal carbon dioxide (ETCO2). ETCO2 is the partial pressure of carbon dioxide (CO2) at the end of an exhaled breath. Until recently, cryonics standby kits were equipped with disposable colorimetric ETCO2 detectors. Some limitations of the disposable ETCO2 detectors [...]

Stabilization in cryonics requires immediate administration of vasoactive medications to maintain blood pressure, thereby assisting and enabling adequate perfusion during cardiopulmonary support. Traditionally, vasopressors such as epinephrine have been administered intravenously, requiring skilled technicians to establish an IV line as quickly as possible. Unfortunately, even the best technicians often encounter difficulties in obtaining an IV [...]

The Autopulse presents an alternative to the (high impulse) active compression-decompression devices that cryonics organizations currently employ to provide cardiopulmonary support (CPS) during stabilization. The Autopulse uses batteries instead of compressed oxygen and is easy to set up and operate. Disadvantages include its cost, limited patient size range, and the modifications that cryonics organizations [...]