SUDDEN INFANT DEATH SYNDROME (COT DEATH)

Sudden infant death syndrome (SIDS) is the sudden and unexpected death of an infant younger than one year old , for which a full exmination can give no explanation. SIDS occurs most often during sleep.

The cause of SIDS is still unknown. SIDS is best described by the “three circle model”, which states that it concerns a vulnerable baby who is faced with exogenous stressors during a critical period in his or her development (first year of life) and who, as a result of this, passes away.

The notion of vulnerable baby relates to the underlying cause of SIDS. Studies conducted during the last few years provided several new indications. Various genetic variations (polymorphisms) are said to be found more often in infants who died of SIDS. There are reports of abnormalities in the brainstem, more specifically in the region that controls breathing and arousal. More and more studies indicate that in a life threatening situation the arousal response of these children is not working properly, which explains the absence of an adequate reaction. Finally 5 % of the infants showed abnormalities in the conduction system of the heart, which could explain why they pass away so suddenly. So far there are no tests that indicate which children are at higher risk of SIDS.

By definition SIDS occurs during the first year of life. The first year is characterized by an important phase of brain growth and brain “ripening”. During that same year the fat layer increases, which causes important changes in the body temperature regulation. Furthermore at the same time the autonomic nervous system continues to develop.

The last circle contains the exogenous factors. Epidemiological research has shown that certain factors occur more often in children that died of SIDS. Factors that play an important role are sleeping belly down, smoking, an increased environmental temperature and sleep environment. Prevention campaigns have been organised to alert the public to the danger of these factors. Since the start of these campaigns thefrequencyof SIDS occurrences has significantly decreased in several countries. This evolution was also seen in Flanders once the campaign was started in 1993.

In spite of the big success of these campaigns SIDS remains the most important cause of infant death. Therefore further research into the cause and prediction of SIDS is absolutely essential.

At this moment we can only try to avoid SIDS by strictly applying the prevention measures to all infants as we do not know which children are at higher risk.

Recommended steps:

1.       Put your baby to sleep on his or her back.

Prone sleeping (belly down) increases the risk of SIDS and has to be avoided at all costs. Side sleeping should also be avoided as some infants may roll from the side and end up on their belly. From birth onwards all babies should be put to sleep on their back, which is also the most natural position for a baby.

2.       Smoking.

Smoking during pregnancy increases the risk of SIDS. Smoking after birth (by the mother as well as the father) also leads to a higher risk. There is a direct relation between the number of cigarettes smoked and the risk of SIDS.

3.       Temperature.

Environment temperature also being a risk factor, it is recommanded to keep the room temperature at 20 degrees during the first 8 weeks and at 18 degrees once the baby is two months old. Quilts should be avoided because they increase the body temperature much more than traditional blankets or sleeping bags.

4.       Supervision.

Regular and direct supervision during every sleeping period is the only reliable way to check   on a sleeping child. Epidemiological studies have shown that co-sleeping (parents and child sleeping in the same room but in separate beds) until the age of six months decresases the risk of SIDS.

5.       Bedding.

      A safe bed is a bed that has side wall as well as bottom ventilation. Quilts should be avoided, just as any other material that could lead to suffocation (pillows, teddy bears, soft toys,… ). Further advice on this subject can be obtained from the organisation“ Kind en Gezin”.

6.       Bed-sharing or sleeping together.

      Although this is common practice in several cultures, in the Western world bed-sharing seems to lead to a higher risk of SIDS. This is especially due to the fact that the beds are not safe enough because of frequent use of quilts, pillows and soft mattrasses. A second important factor is the danger of parents being overtired, smokers or sedated by alcohol or drugs. For those reasons sleeping together should be avoided, especially so on other places like armchairs or couches.

7.       Sudden environmental changes.

      In recent years the number of children who died of SID while staying with a day care mum or in a day care center has increased, mainly during the first days of their stay. For that reason it is recommended to prepare an infant gradually for this type of change by making several visits in advance and letting them stay in the new place for short periods.

8.       Medication

      Cough syrups should be avoided because they often contain sedative substances and may cause depression of breathing.

      Other risk factors are dummies and heights (2000 meters or more).

      Polysomnographic screening has no predictive value whatsoever. There is also no evidence of a positive effect of monitoring on the incidence of SIDS. Monitors are only used when infants exhibit immature respiratory and heart rytm patterns and therefore run a higher risk in case of an acute problem.

      Most likely SIDS has several different causes. There is only way way of finding them: further research. At this stage the preventive measure have proven to be the only efficient way of decreasing the number of SID cases.

this information was provide to us by Prof. Naulaerts and Dr. Degomme