Can a clinically dead person be revived several hours later if the body was cooled?

Question

The blog, Seyisanchez, claims that:

According to the latest available statistics, nearly twice as many patients are resuscitated [at Stony Brook University Hospital in New York] every year compared to other U.S. hospitals — the average resuscitation rate at Stony Brook is an astounding 33 percent, which contrasts sharply with the 18 percent average elsewhere. So how does it all work? The techniques [Dr. Sam Parnia] advocates are not cryogenics – freezing the body immediately after death – but cooling it down to best preserve brain cells while keeping up the level of oxygen in the blood. This buys time to fix the underlying problem and restart the heart, he claims.

Also, from here, the Dr. Parnia restates his claim (along with more detailed explanation of the cooling process):

With today's medicine, we can bring people back to life up to one, maybe two hours, sometimes even longer, after their heart stopped beating and they have thus died by circulatory failure.

Is this true?

Answer 1

A 4 years old child broke through the ice of the frozen lake. He was rescued from the water and transported to the hospital by a helicopter. Initial findings:

• no heart rhythm
• nonreacting pupils
• core body temperature 19.8 °C (68 °F) He was in cardiac arrest for 88 minutes and then successfully resuscitated (with some complications - acute respiratory distress syndrome - but recovered fully). Successful resuscitation of a child with severe hypothermia after cardiac arrest of 88 minutes

Whole body cooling for 72 hours was associated with less brain damage in infants who suffered from brain ischemic injury during delivery compared with no cooling. The effect of whole-body cooling on brain metabolism following perinatal hypoxic–ischemic injury

Cerebral hypothermia can safely improve intact survival in term infants with neonatal encephalopathy. Beneficial effects of hypothermia:

• Decrease of basal metabolic rate (~7% for each °C), which means lower oxygen consumption in the cells and therefore prolonged cell survival when the oxygen delivery to the cells is impaired
• Slowed inflammation process Clinical applications of induced hypothermia

From the same source (oxfordjournals.org) from y.2006:

The admission body temperature seems to be a major determinant for long-term mortality after stroke. They concluded that ‘hypothermic therapy in the early stage, in which body temperature is kept low for a longer period after stroke onset, could be a long-lasting neuroprotective measure’. Since then, there have been numerous animal models and some preliminary studies but no conclusive results. The Cochrane review stated that further trials were indicated.

Here's another short story. A woman was clinically dead (no heart rhythm, no breathing). Paramedics used the Arctic Sun technology (they wrapped her in some sort of "cloth" that can be filled with a cold fluid) and thus induced hypothermia. The woman has survived. Practically no technical data (time, woman's age, the underlying disease - supposedly heart arrhythmia...) are provided, though. From Clinical Death to Restored Life