A team of medical researchers at the University of Maryland School of Medicine and Hospital here has been awarded a $2.8 million federal grant to search for the cause of sudden infant death syndrome - often called crib death - the inexplicable killer of 10,000 babies each year.

The project will involve sophisticated monitoring in both the hospital and the infants' homes of the feeding habits breathing and heart rates, crying patterns - even the cuddliness - of some 4,000 infants expected to be born at University Hospital over the next five years.

Dr. Alfred Steinschneider, leader of the multi-discipinary research team effort was cautious yesterday in assessing the team's chances for discovering the elusive cause of the syndrome during the five-year study.

"If were really crazy lucky," said Steinschnider, one of the nation's leading authorities on what little is known about sudden infant death "at the end of 5 or 10 years we may know if we're heading in the right direction."

The syndrome is the No. 1 killer of babies older than one month. It can also work psychological havoc on the families it strikes, leaving the parents with lifelong feelings of guit over a death over which they had no control and yet are at a loss to explain.

While there have in the past been numerous studies of the problem, all have been carried out on much smaller scales, with different institutions studying different aspects of the syndrome.

"We are trying to develop a profile" of infants who might be susceptible to sudden death, said Steinschneider, "and the infants we identify as high risk will be sent home with monitors."

The monitors, which parents will be taught to operate, are desgined to record the infants' breathing and heart beat.

The monitoring resembles an alarm clock, explained Steinschneider, the alarm of which is reset by every breath the infant takes. If the infant does not breath for, say, 20 seconds, the alarm sounds, summoning the parents.

"The parents will be taught mouth-to-mouth resuscitation" in case it is needed to revive the infant he said. In most cases, however, all that is called for is a light finger flick on the sole of the foot, he said.

The most common theory now about crib death is that it is caused by apnea - spells during which the infant stops breathing. All persons experience such spells when they sleep, but in most cases they awaken and resume breathing.

Physicians at some major medical centers have, on occasion, provided home monitors for infants judged to be susceptible to syndrome. The Maryland study, however, will hook the monitors up to recording devices to provide permanent research records of the monitoring.

The parents involved in the study, all of whom will be volunteers, will be provided with logs to record information about their baby's eating, sleeping and other activity.

While the infants are in the hospital, their cries will be analyzed by speech pathologists and their various bodily functions will be studied and recorded. The researchers hope this will eventually enable them to determine whether there are certain physical actions or characteristics that mark a baby at risk.

The project will include studies of the infant's metabolism and chemistry. In addition, a small group of mothers will be picked at random for urine studies starting in their 30th week of pregnancy, again with the thought of finding characteristics common to babies who become victims of the syndrome.

The physicians will also save samples of the placentas of all babies born at the hospital during the term of the study. The placentas of those infants who die of the syndrome will then be compared to the placentas of other babies to see if some chemical clue can be found.

At the same time, extensive autopsies and tests will be performed on babies who die of the syndrome to "see if there are subelechemical abnormalities," said Stelnschneider.

The researcher, who has a doctorate in paychology in addition to his doctorate in medicine, said that about 10 to 15 per cent of the 4,000 babies will be sent home with monitoring equipment.

While estimates place the number of infants truly at risk at about 5 to 6 per cent, more will be monitored in the study to make sure all potential victims are included, he said.

Steinschneider said his group originally considered dividing the "high risk" group into two catagories: one that would be monitored and studied while the other would be used as a control.

However, he said, it was decided that it might not be ethically proper, after already having split the hospital's infant population into those to be studied and those to be left out of the project, to ignore a portion of the study population with a known risk of death.

Steinschneider also said that "if a baby (in the general hospital population) is identified as having problems it will be hard not to monitor it," even though it isn't in the study.

In addition to working with the infants, the Maryland team intends to work with the parents of sudden death infant syndronie victims to see what can be done to aid them in coping with their tragedy. There are already some referral systems and aids for such parents, said Steinschneider, "but we need to see if more is needed."