Medicine: Reversible Death

• Share

"Sudden death," even from a massive heart attack or in shock on the operating table, is not really sudden. After the heart stops, there may be a few last, shallow breaths. The brain lives on for five or six minutes, and perhaps longer under some conditions. In Moscow last week, at the Fifth International Congress on Biochemistry, Soviet investigators reported new findings about the dying brain, and new means of bringing the "dead" back to life.

A tall, grey-haired woman doctor, Maria Sergeevna Gaievskaya, described methods developed in Dr. Vladimir Aleksandrovich Negovsky's Resuscitation Laboratory in Moscow. The lab is already famous for its success in reviving thousands of suffocation victims, some heart attack victims, and some stillbirths by pumping blood-bank blood into arteries under pressure during the six minutes after "clinical death." Dr. Gaievskaya's findings offer an explanation of that six minutes of grace.

Autopsies after resuscitation has been tried often show that brain cells have been irreparably damaged. It has been assumed that this damage resulted simply from the brain's being starved of oxygen. The Negovsky Laboratory has found that the cause of the damage may have been too much oxygen.

By the Gaievskaya theory, when heart stoppage cuts off the blood supply, the brain can no longer get oxygen to burn sugar for its energy. So it switches to a cruder, less efficient way of breaking down sugar without blood-borne oxygen (anaerobic glycolysis) to extract whatever energy it can. This emergency system will work for about six minutes. If the body is revived during this time, the brain makes a gradual transition, taking half an hour, back to using oxygen.

The critical aspect of this process is to avoid flooding the brain with oxygen. If resuscitation is begun within six minutes, so that oxygenated blood resumes its flow to the brain, the switchover from anaerobic glycolysis will nevertheless be gradual and must not be rushed, said Dr. Gaievskaya. Extra oxygen given too soon, she warned, may damage the brain as surely as the lack of oxygen ultimately does in normal death.

In the hope of extending the period during which revival is possible (that is, the period of glycolysis), perhaps to as long as half an hour, Dr. Gaievskaya is experimenting on dogs by chilling the brain, to 77° F. She then takes as long as 24 hours to let the brain return to normal oxygen use. Dr. Negovsky's method of prompt resuscitation is claimed to have saved thousands of Russians who were "clinically dead"; Dr. Gaievskaya's modifications would extend its scope in both time and numbers.