What is crib death or the Sudden Infant Death Syndrome
Crib death is the common term used to describe a sudden and unexpected death of an infant, which is originally unexplained. The medical term is Sudden Infant Death Syndrome (SIDS). Some of the cases of a sudden and unexpected death may be explained, such as accidents, quickly developing lethal infections or certain metabolic conditions. Only the cases which were carefully examined and remained unexplained are defined as cases of SIDS.
The definition in the medical literature: a sudden and unexpected death of a healthy infant which remains unexplained even after completion of the post mortem examinations, including a forensic autopsy, a death scene investigation and an examination of the infant’s medical history. This definition creates a diagnosis by exclusion – all possible causes which may explain the death should be denied and only then can the diagnosis be SIDS.
SIDS is the main cause of death between the ages of one month and one year; 99% of the cases occur before the age of six months; in Israel there are approximately 60 cases of a sudden and unexplained death of infants a year; in the western world it is between 0.7 to 1 per 1000 live births; cases of SIDS are most common between the ages of 2-4 months; the death occurs mostly at night and during sleep.
Causes of SIDS
Despite thousands of studies there has not yet been found an explanation or a cause to identify or predict when a baby is at risk. Since babies who died are no different than other babies, physiologically or immunologically, one of the theories is that it maybe due to a defect or several minor defects which are hard to trace and which under specific circumstances and during a specific period of the baby’s life, in which it is more vulnerable, create a cumulative effect causing its death.
- Prone sleeping position – since 1998 parents are instructed to place the baby only on his back while sleeping (side sleeping position increases the risk of SIDS two times more compared to lying on the back). Even though the cause of SIDS has not been found, preventing the positional risk factor (lying on the stomach) has led to a drastic decrease of up to 70% in death rates from SIDS. Despite the drastic decrease in the number of deaths, SIDS is still the main cause of death of infants between the ages of one month and one year.
Researchers are sure that in order for death to occur there has to be an external trigger, or a combination of circumstances, and those are aggravated when the infant is placed on his stomach.
In an anatomical study, Dr. Shatz and her colleagues discovered that when an infant is lying on his back – the head and neck are stretched in a straight line with the back and the airways are fully open. All arguments about the dangers of placing the baby on his back during sleep were refuted by studies: there is no danger of more vomiting, flattening of the bones of the skull or a flawed orthopedic development of the back.
The recommendation is unambiguous: the baby should be placed only on his back!
- After eliminating the prone position as a risk factor (by placing infants on their back when asleep) it was discovered that the main risk factor today is smoking: smoking by the mother during pregnancy, and smoking around the baby after birth. Smoking can be and should be prevented around the baby, and thus the risk of SIDS can be reduced.
Many people ask why not place the baby on his stomach, for it appears that when the baby is placed on his back, there is a greater danger of suffocation from vomiting, and in the past it was customary to place babies on their stomach for fear they might suffocate from vomit. Today, due to extensive research in the western world and mainly in England and Australia, the researchers believe that the prone position is a risk factor for SIDS, but it does not reduce the danger of morbidity or mortality from other causes, including the inhalation of food into the lungs. This conclusion was reached after more than 80% of the babies found dead and who were diagnosed as SIDS cases were found lying on their stomach.
The risk of the prone position, so it was discovered, is 3 to 5 times higher than that of a non-prone position. The researchers who linked between placing an infant on his stomach and SIDS believe that this position might cause a mechanic obstruction of the airways and block the nose and mouth – leading to suffocation. In addition, when the infant is placed on his stomach he exhales carbon dioxide into the sheet, but because of the infant’s position, it does not spread and the infant inhales it back – which might endanger his life. Additional problems which may be caused by the prone position: pressure on the intervertebral artery, and over heating due to the fact that in this position the heat tends to spread less compared to a non-prone position.
Yet, when awake and supervised by an adult, it is recommended to give the baby sufficient tummy time, so he experiences varied positions and develops his motor skills.