Apert syndrome was named after the French paediatrician Eugène Apert, who first described the collection of signs in 1906. It is a congenital disease that is a form of acrocephalosyndactyly, and is characterized by malformations of the skull, hands, feet and face.
It is a rare disease with an incidence of around 1 per 160,000 live births. It is an autosomal dominant complaint and affects both females and males equally. Interestingly however the vast majority of cases are due to sporadic mutations, but there is an association with increased paternal age.
It is thought that the affected chromosome is chromosome 10, and there are two main identified gene defects affecting fibroblast growth factor receptor 2 gene. The resultant abnormal receptor prevents apoptosis of cells, and so in the case of those affected by Apert syndrome, digits on both hands and feet may be fused. These fusions can be either cutaneous or bony. Receptors found in the cranium are also affected and thus cause premature fusion of sutures resulting in craniosynotosis.
Apert syndrome is always apparent at birth. This is due to the characteristic hand and foot deformities, although the facial deformity may be less obvious in some cases.
The syndrome is characterized by a number of typical features. Firstly it accounts for 4.5% of all craniosynotosis cases. Premature fusion of suture lines can be of both the skull and the face, and these can be variable in number and sites affected. Where there is fusion of sutures there is reduced bone growth, and this is compensated for in areas where there is no fusion. Thus Apert children tend to have characteristic shaped skulls. Brachycephaly is common, this is where the coronal sutures fuse prematurely resulting in a reduced distance from the front of the skull to the back. Usually both coronal sutures are affected. The severity and rate of progression of the skull will depend on the sutures affected.
Other facial characteristics include mid-face hypoplasia, hypertelorism and choanal stenosis. If growth of the brain surpasses skull development, then this will ultimately lead to an increase in intracranial pressure. Another result of abnormal skull development is that the orbits tend to be shallow resulting in protrusion of the eyes, and sometimes inability of the lids to close. This is known as exorbitism.
Other characteristic features include a multi-digit hand and foot syndactyly, which is bilateral, but not always symmetrical. Children with Apert syndrome are also described to have other associated anomalies. These include cardiac defects, polycystic kidneys and pyloric stenosis, all of which are rare.
The major anaesthetic concerns relate to the airway. Bag mask ventilation can sometimes be difficult due to mid-face hypoplasia. Often these children suffer from obstructive sleep apnoea, and therefore are prone to becoming obstructed on induction and emergence. This is usually easily alleviated by the use of airway adjuncts. Some Apert children may also suffer from central apnoea.
It has been reported that these children suffer a higher incidence of bronchospasm, although this was only detailed in one paper. Children with Apert syndrome have profuse secretions that may cause wheeze and contribute to an increase in airway irritability. There is an association with fusion of the cervical vertebra (C5/6), however this does not compromise intubation.
Another challenge for the anaesthetist is intravenous access. This can be made more difficult when one or more limbs are being operated on. As these children may return to theatre for repeat procedures this issue can become increasingly more problematic. As a result, some anaesthetists feel that for short procedures, e.g. change of dressings or CT scans, intravenous access is not mandatory. In an emergency an intra-osseous needle may be placed, or intramuscular drugs can be used.