Depressed Metabolism

It is common medical knowledge that after 5 minutes of cardiac arrest the prospects of successful resuscitation without neurological impairment become progressively bleak. But there is less consensus on the mechanisms of such injury. One strong candidate is what is called the “no-reflow” phenomenon. No-reflow refers to the impairment of perfusion of the brain after [...]

Under ideal circumstances cryonics patients are stabilized immediately after pronouncement of legal death by restoring  blood flow to the brain, lowering temperature, and administering medications. In most cryonics cases, however, there is a delay between pronouncement of legal death and start of cryonics procedures. In some cases there are no stabilization interventions at all. Provided [...]

It has been shown that perfusability of the brain is significantly compromised after long-term (>5 min) ischemic events (the “no reflow” phenomenon). Improving cerebral blood flow after circulatory arrest is one of the fundamental objectives of human cryopreservation stabilization protocol.  To that end, cryonics organizations administer the resuscitation fluid Dextran-40 and the drug Streptokinase to [...]

In “The chemistry of neuroprotection”, the author argues convincingly that there could be great benefit from a systematic and rigorously scientific study of the physical chemistry of putative neuroprotectants vis-à-vis their pharmacological effect. However, the first example used of the earliest thinking in this direction (which comes, not surprisingly via V. A. Negovskii, the father [...]

In a review of the 1998 21st Century Medicine seminars, Cryonics Institute president Ben Best writes:
“The presentations impressed upon me how much witchcraft and how little science has gone into the study of cryoprotectant agents (CPAs). This might be understandable in light of the fact that most cryobiologists are, in fact, biologists. I suspect [...]

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 [...]

Induction of hypothermia can reduce injury to the brain when it is deprived of oxygen. How fast do we need to cool a patient during cardiac arrest or stroke to prevent irreversible injury to the brain?
It is an established fact that induction of hypothermia prior, during, or after circulatory arrest can reduce brain injury. As [...]

The blog Al Fin reports on polyethylene glycol (PEG) as an acute treatment for traumatic brain and spinal cord injury. PEG is hypothesized to confer cytoprotection by sealing damaged cell membranes. As such, PEG would also seem a promising candidate for the treatment of acute neural insults in which progressive cell permeability / damage plays [...]

Neuroprotective agents for stroke continue to fail in clinical trials. One important reason is that the therapeutic window for many of those agents is too narrow to confer benefits to acute stroke victims. It would be desirable to have a potent neuroprotectant agent that has a wide therapeutic window, few side effects, and can be [...]