Interventional radiology clinical outcomes

This page gives on overview of the Interventional Radiology Service and how it measures the results of one of its procedures, the central venous catheter insertion, at Great Ormond Street Hospital (GOSH).

Overview of the service

The Interventional Radiology Service at GOSH offers a comprehensive range of interventional radiology procedures for children from newborns to 18 years of age as part of the diagnosis and treatment of a range of conditions.

Interventional radiology refers to a range of techniques which rely on the use and guidance of radiological images such as X-ray and ultrasound to precisely target therapy for the patient.

Interventional radiology is usually performed using needles and narrow tubes called catheters rather than by making large incisions into the body as in traditional surgery. This approach has many benefits including minimising the pain for the patient, the risk of infection, hospital stay and recovery time. These procedures are used to both diagnose and treat patients.

The Interventional Radiology Service does not usually admit patients directly under their care; instead they see and treat patients on behalf of other teams in the hospital who refer their patients to us for specific procedures.  

Currently the Interventional Radiology Service performs around 3,100 procedures per year. The procedures include:

• central venous access

• biopsy

• oesophageal dilatation

• airway intervention

• feeding tube insertion

• joint injections

• angiography, angioplasty and embolisation

• sclerotherapy

• percutaneous urinary tract stone removal

• thrombolysis

The proportion of procedures undertaken is as follows:

• 48 per cent for venous access
• 13 per cent for biopsy
• 9 per cent for airway
• 8 per cent for arterial
• 7 per cent for vascular malformations
• 3 per cent for miscellaneous
• 2 per cent for other venous procedures

GOSH is the only hospital in the UK that employs full-time paediatric interventional radiologists.

The following section provides information on the interventional radiology procedure results for central venous access.

Central venous access procedures

With this procedure, the interventional radiologist aims to safely and effectively insert a thin catheter into a vein so that fluid, nutrition or medication can enter the patient’s bloodstream and blood tests can be taken without needing to use a needle.

Almost every service in the hospital refers to the Interventional Radiology Service for this procedure. The most common reasons for central venous access are chemotherapy, intravenous feeding, haemodialysis and prolonged antibiotic treatment.

Central venous access involves making two incisions, one to tunnel the catheter under the skin and the second at the site where the catheter is inserted into the vein. X-ray and ultrasound are used to perform the procedure.

The procedure is carried out in a dedicated interventional radiology suite. The insertion procedure will require some type of sedation or anaesthesia in most children.

Some patients come into the hospital for the procedure and in most cases they can go home the same day. The procedures takes 40 to 60 minutes, including anaesthetic time.

How do we measure the results of central venous access procedures?

The interventional radiology team reviews the insertion of every child that undergoes central venous access to see if the procedure was successful.

A successful insertion is defined as a visit to the interventional radiology suite where it was possible to make the central venous access insertion, even if it was not at the first attempt.

This means that a patient with a successful insertion leaves the suite with a catheter inserted.

If the procedure is not successful the team will try again at another time and potentially try an alternative vein for access. Evidence suggests that the most common cause to the procedure not working the first time is because the child is already critically ill and trying again is likely to be successful when the child is in better health.

Central venous access catheter insertion success rates

The interventional radiology team are successfully inserting central venous access catheters 99.8 per cent of the time over the last nineteen months.

As there are currently no defined success rate standards for children, the interventional team use adult success rate standards from the Society of Interventional Radiology to compare their performance.

These standards suggest that where success rates fall below 95 per cent there is a need to review procedures to determine causes and to implement changes if necessary.

This guidance also states that success rates should be lower in children than adults. The interventional radiology team are therefore consistently successful in inserting central venous access catheters and report success rates that are higher than international standards.

The following table shows the monthly number of procedures and number that were successful with the corresponding success rate:

The interventional team also monitor if there has been any complications for the patient after the catheter has been inserted. During this time period the patients that have undergone catheter insertion through central venous access have had no complications.

About the information

This information reviewed all patients that underwent central venous catheter lines since August 2010 until February 2012 and will be reviewed again in January 2013.

Glossary

Central venous access catheter success rate – a visit to the interventional radiology suite during which it was possible to make the central venous access insertion, even if it was not at the first attempt.