What is the purpose of a spinal cord shunt (cerebrospinal fluid shunt)?

From the Guidelines

Spinal cord shunts are not directly recommended for aneurysmal subarachnoid hemorrhage (aSAH) patients, but rather for conditions like syringomyelia or spinal CSF leaks, and the management of aSAH-associated hydrocephalus should be guided by the latest evidence. When considering the management of hydrocephalus in patients with aSAH, the most recent guidelines suggest that permanent cerebrospinal fluid diversion, such as ventricular shunting, is recommended for chronic symptomatic hydrocephalus 1. The decision to implant a shunt should be based on the individual patient's condition, taking into account factors such as the presence of acute or chronic hydrocephalus, the patient's neurological grade, and the risk of shunt dependency 1. Key considerations in the management of aSAH-associated hydrocephalus include:

• The use of cerebrospinal fluid diversion, such as external ventricular drainage (EVD) or lumbar drainage, for acute symptomatic hydrocephalus 1
• The consideration of permanent cerebrospinal fluid diversion for chronic symptomatic hydrocephalus 1
• The identification of predictors of shunt dependency, including poor admission neurological grade, increased age, and the presence of intraventricular hemorrhage 1 The primary goal in managing aSAH-associated hydrocephalus is to improve neurological outcomes, and permanent CSF diversion has been shown to achieve this 1. In terms of specific shunting procedures for conditions like syringomyelia, a syringoperitoneal shunt is commonly used, which involves diverting fluid from the syrinx to the peritoneal cavity [example from general medical knowledge]. However, the provided evidence primarily focuses on the management of aSAH-associated hydrocephalus rather than spinal cord shunts for other conditions. Therefore, when considering spinal cord shunts in the context of aSAH, it is crucial to prioritize the management of hydrocephalus according to the latest guidelines and evidence 1.

From the Research

Spinal Cord Shunt Overview

• A spinal cord shunt is a medical device used to divert cerebrospinal fluid (CSF) from the brain to another part of the body, typically the abdomen, to relieve pressure and prevent damage to the brain and spinal cord.
• The most common type of shunt used is a ventriculoperitoneal (VP) shunt, which is implanted in the ventricles of the brain and drains CSF into the peritoneum 2, 3, 4, 5.

Types of Shunts

• Ventriculoperitoneal (VP) shunts: drain CSF from the ventricles of the brain into the peritoneum 2, 3, 4, 5.
• Lumboperitoneal (LP) shunts: drain CSF from the lumbar cistern into the peritoneum 4.
• Spinal arteriovenous (AV) shunt: a rare condition where there is an abnormal connection between arteries and veins in the spinal cord, which can be treated with endovascular treatment or direct surgery 6.

Complications and Failure Rates

• VP shunts: have a high risk of complications, including infection, obstruction, disconnection, and overdrainage or underdrainage of CSF 2, 3, 5.
• LP shunts: have a lower complication rate compared to VP shunts, with a total complication rate of 12.98% compared to 23.80% for VP shunts 4.
• Shunt revision rates: can be as high as 51.9% for VP shunts, with the majority of revisions occurring within the first 6 months after initial placement 5.

Treatment Outcomes

• VP shunts: can be an effective treatment for hydrocephalus, with a good outcome seen in 63.4% of patients, but with a high risk of complications 3.
• LP shunts: have been shown to be a safe and equally effective choice for treating communicating hydrocephalus, with improved radiological outcomes 4.
• Direct surgery for spinal AV shunt disease: has been shown to have better treatment outcomes compared to endovascular treatment, but with a higher risk of complications 6.