During mechanical ventilation of young children, problems may arise due to the additional dead space of the ventilation circuit. This may lead to respiratory acidosis and even hypoxia in the child.

A 3-month-old boy suffered from frequent apnoea. He was mechanically ventilated for this. Shortly after its initiation, he developed severe respiratory acidosis, hypoxemia and circulatory insufficiency. This was due to a large additional dead space caused by the use of equipment components made for adults. After he was switched to a circuit suitable for himself, he recovered rapidly.

As a rule of thumb, an additional dead space of 1.5-2 ml/kg body weight is acceptable in young children. Emergency wards for young children should have specific equipment to mechanically ventilate them, and have a protocol paying explicit attention to the dead space.

Conflict of interest: none declared. Financial support: none declared.