Neurosurgery clinical outcomes

The neurosurgical unit of Great Ormond Street Hospital (GOSH) is the largest paediatric neurosurgery unit in the United Kingdom, and the only paediatric neurosurgery unit in the North Thames area.

The unit performs around 1000 procedures each year, providing neurosurgical input to various highly specialised multidisciplinary teams for the management of conditions such as:

• Hydrocephalus
• Childhood brain and spinal tumours 
• Congenital and acquired craniofacial disorders
• Congenital spinal disorders 
• Epilepsy
• Head injuries 

As GOSH is one of only four supra-regionally funded craniofacial centres and one of the NHSE’s four specialised Children’s Epilepsy Surgery Service (CESS) centres, the neurosurgery unit is responsible for an increasing volume of craniofacial and, in particular, epilepsy cases.

In November 2019, the unit was commissioned as a highly specialised service for foetal myelomeningocoele repair. Myelomeningocele is a type of spina bifida, a condition that happens before birth where the spinal column and spinal cord are not properly formed. Traditionally this is treated by operating on the baby shortly after birth. Recent studies show that for some babies this can be repaired by operating on the baby whilst still in the womb (fetal surgery). A total of 21 of these operations have been carried out by GOSH with University College London Hospitals NHS Foundation Trust (UCLH).

The following table shows the number of neurosurgical operations at GOSH for the past five years.

The GOSH neurosurgical unit has a zero tolerance approach to adverse events including surgical complications. Every such event is reviewed in a weekly meeting attended by all members of the unit, and actions designed to prevent repetition are discussed. Adverse events are defined here as “Any untoward event related to a child’s admission to the neurosurgical unit that had the potential to increase their stay in hospital and/or produce a temporary or permanent worsening of their health.”

It is important to emphasise that while a number of reports use surgical complications as a measure of performance, within the neurosurgical department at GOSH we choose to use the adverse event rate (which may or may not be related to surgical complications) as we feel this better reflects the patient’s experience and provides a more transparent view of our performance. For example, if a child were to develop a chest infection following an operation, this is unlikely to be reported as a surgical complication but we still report it as an adverse event.

Adverse events are graded as follows:

1. No increase in hospital stay* and no neurological injury (threatened or actual)
2. Increase in hospital stay* but no neurological injury (threatened or actual)
3. An event that either threatened or caused neurological injury
4. Death

*Includes readmission and/or extra procedure(s) with general anaesthetic

*procedures undertaken in the department that are not neurosurgical, such as muscle biopsies, have not been included.

Variation is expected from year to year as adverse events vary with the complexity of patients treated. Over time we have seen an increase in the number of complex patients referred to our unit, including several from outside our region. We continue to monitor all our adverse events closely.

*non-primary neurosurgical procedures such as muscle biopsies etc have not been included

† Vascular related includes stereotactic radiosurgery

*non-primary neurosurgical procedures such as muscle biopsies etc have not been included

These percentages of adverse events are within our expected range of results. Some variables include more complex vascular procedures in recent years.

A shunt is a device that diverts accumulated cerebrospinal fluid (CSF) around obstructed pathways and returns it to the bloodstream. It is inserted in a neurosurgical procedure so that the upper end is in a ventricle of the brain and the lower end leads either into the heart (ventriculo-atrial) or into the abdomen (ventriculo-peritoneal). Permanent shunts are intended to stay in place for life. However, sometimes additional operations are required as a result of mechanical failure of the shunt, infection of the CSF, shunt blockage, or other reasons.

We have included all shunt procedures, where the shunt was inserted, revised or internalised. We have included lumbar-peritoneal shunts, valveless shunts and subgaleal shunts, but excluded external ventricular drains (EVDs).

Shunt infections occur when CSF microscopy or culture demonstrate an organism in the CSF, or when there is an abnormally high number of white blood cells in the CSF, in the presence of fever, shunt malfunction or neurological symptoms. Shunt infection requires removal of the shunt and subsequent antimicrobial treatment. The shunt is then re-inserted once the infection has been treated.

The early shunt re-operation rate is defined as the proportion of patients who require a second shunt operation within 30 days of the first operation for any reason.

Numerator: Number of primary (initial) shunt procedures requiring a second shunt procedure within 30 days of the initial procedure, for any reason

Denominator: Number of primary shunt procedure (first or initial procedures only)

Numerator: Number of shunt procedures requiring a second shunt procedure within 30 days of the first procedure, for any reason

Denominator: Total number of shunt procedures

Improvements in shunt infection rates have been contributed to by a robust shunt surgery protocol and regular three-monthly infection audit meetings for the last three years. We are also grateful for the excellent collaboration with a consultant microbiologist with neurosurgical interest.