Overview of Ventriculostomy
Ventriculostomy is a common emergency brain surgery carried out by neurosurgeons around the world. In fact, in the US alone, approximately 20,000 people have this procedure every year.
This procedure was initially created by Claude-Nicholas Le Cat, although it wasn’t perfect and faced criticism from the likes of Robert Whytt and Benjamin Hill due to poor results.
However, the procedure was significantly improved in 1941 by Ingraham and Campbell. They introduced a number of important changes, like a closed system to drain fluid efficiently, a stopcock to prevent too much fluid from being drained, a drip chamber to stop any backflow of cerebrospinal fluid (the fluid that surrounds your brain and spinal cord), and a flexible tube made of silicone that could be inserted beneath the skin.
These important tweaks helped ventriculostomy to become a more accepted and commonly used procedure worldwide. Later on, Franklin Robinson added the ability to monitor ventricular pressure during the procedure. Furthermore, a group called the Brain Trauma Foundation recommended that this surgery be used for severe head injuries. They included this as part of their official guidelines in 1995.
Anatomy and Physiology of Ventriculostomy
Herophilus and Erasistratus were the pioneering scientists who first described the structure of ventricular system within the brain. Following their work, Domenico Felice Antonio Cotugno provided more details about a fluid within these structures, called cerebrospinal fluid (CSF).
The ventricular system, located inside the brain, develops from small cavities in the early stages of brain growth. The four key components of the system are formed from different parts – the cavity within the rhombencephalon (or hindbrain) evolves to form the fourth ventricle, the cavity within the diencephalon (interbrain) forms the third ventricle, and those of the telencephalon (forebrain) become the lateral ventricles. Finally, the small cavity within the mesencephalon (midbrain) develops into the aqueduct that connects the third and fourth ventricles.
Why do People Need Ventriculostomy
Ventriculostomy is a medical procedure, and there are several reasons a doctor might suggest having it. Some of these reasons include:
1. Quick development of noticeable symptoms of too much cerebrospinal fluid (hydrocephalus) – this can be after brain hemorrhaging, strokes, or meningitis. For reference, a brain hemorrhage is when there is sudden bleeding in the brain, and meningitis is an infection that causes inflammation around the brain and spinal cord.
2. Monitoring of intracranial pressure (ICP) – this means checking the pressure inside the skull where the brain is located.
3. As a support to manage issues affecting ventriculoperitoneal shunts that either don’t work properly or are infected. A ventriculoperitoneal shunt is a tube doctors place inside the head that helps fluid drain out of the brain.
4. As an aid to relax the brain during surgery when there is swelling (brain edema) in the brain tissue.
5. Helping to plan therapeutic treatments like thrombolytics or antibiotics for managing vasospasms. Thrombolytics are medications that dissolve blood clots, antibiotics help fight infections, and vasospasms are sudden, involuntary contractions of a blood vessel.
When a Person Should Avoid Ventriculostomy
In certain conditions, a medical procedure known as a ventriculostomy may not be appropriate or safe. For instance:
1. If you are taking blood-thinning medications, also known as anticoagulant drugs, the procedure may not be safe for you, because these drugs could increase the risk of bleeding during the procedure.
2. If you have disorders that affect your blood’s ability to clot properly and prevent bleeding, a ventriculostomy may carry an increased risk.
3. If you have an infection on your scalp, this could interfere with the procedure, as it often involves making a small hole in the skull. An infection at the procedure site could risk spreading deeper into the body.
4. If you have a brain abscess, which is a pocket of pus in the brain due to a bacterial infection, the procedure could potentially cause harm by spreading the infection.
Equipment used for Ventriculostomy
When preparing for a medical procedure, the following items are usually included:
1. Items to get ready before the procedure: Non-sterile gloves, soap, brush, hand towel, razor, and a marker pen. These are used to prepare and mark the area where the monitoring devices will be placed.
2. During the operation: A face mask, sterile gown, and gloves for the healthcare professional performing the procedure, an antiseptic solution to clean the area, a drape to provide a clean working area, a local anesthetic to numb the area, a 5-ml syringe possibly to administer the anesthetic, a surgical blade number 15 or 11 to make any necessary incisions, and an ICP (Intracranial Pressure) monitoring kit. This kit typically includes a drill with a drill bit, a bolt (a device to fasten things together), an ICP sensor to measure pressure inside the skull, and a transducer to help with measurements. After the procedure, a suture material (a thread-like material for closing surgical cuts) and a sterile dressing (clean material used to cover and protect the wound) are used.
Who is needed to perform Ventriculostomy?
Your healthcare team for an upcoming operation includes a select group of medical professionals. Leading your care is a neurosurgeon, a doctor who specializes in surgery of the brain and other parts of the nervous system. There’s also a qualified assistant to assist the neurosurgeon throughout the procedure.
An important member of the team is an attending nurse who cares for your overall wellbeing during the process. Managing any discomfort or pain you may feel during the surgery is the job of an anesthetist, who will administer medications to help you sleep and not feel pain.
Last but not least, a general duty assistant (GDA) helps ensure smooth and coordinated care throughout the procedure. Each member of this team contributes their skills and expertise to give you the best possible care and outcome for your operation.
Preparing for Ventriculostomy
Before any medical procedure, it’s really important that patients and their close family members fully understand what the procedure involves, what it’s for, and what the risks might be. To make sure that everyone is on board with what’s about to happen, we also need written consent from the patient.
Keeping everything clean and sterile is a key way to stop infections from happening. This is why we often give preventive antibiotics right at the start of the procedure.
In order to keep procedure-related complications as low as possible, the medical team uses very careful and precise techniques. It’s also important for the patient to be in a relaxed state, usually achieved through sedation, ensuring normal breathing and keeping them comfortable. Local anesthetic is used at the specific site where the procedure is to be performed.
How is Ventriculostomy performed
For certain medical procedures, a device may need to be inserted into your brain. This can be done through a process which involves creating a small hole in the skull. The location where this hole is made is chosen carefully, based on various points in and around your head. These include points like Keen’s point, Kocher’s point, Dandy’s point, Frazier’s point, Paine’s point and Tubbs’ point. Each of those points are located at specific distances from different identifiable parts of the head. For instance, Kocher’s point is a spot on the head that is 1 to 2 cm in front of the coronal suture in the mid pupillary line.
In this procedure, the doctor often follows a guideline to ensure that the device is inserted at the correct angle. This means, the device should be inserted straight in relative to the skull surface. However, due to the curved shape of the skull, this might vary a bit especially in the coronal plane, which is a vertical plane dividing the body into front and back sections.
The ideal placement of the device into the brain through these holes has a success rate of around 86%. In just about 3.1% cases, the device was found to be not working as it should, requiring it to be replaced or repositioned.
For an even higher success rate, various medical technologies like ultrasound, endoscope and neuronavigation, could be used. Just like GPS navigation which guides you on the road, neuronavigation is like a GPS for brain which helps guide the doctor to the precise location in the brain.
Doctors also have a grading system to evaluate how well the device has been placed in the brain. It goes from Grade 1 (the best possible placement) to Grade 3 (placements that may potentially cause some harm to the specific brain areas).
Possible Complications of Ventriculostomy
There are several complications that might occur after a certain type of procedure where a tube is placed in the brain (an external ventricular drain or EVD) to measure pressure or drain fluid. These complications can include bleeding in the brain (10% of cases), infection of the drainage tract (20% of cases), and technical failures, such as not properly placing the tube (5% of cases). Using blood thinners within 96 hours of putting in the EVD can increase the risk of bleeding after the procedure.
Incorrectly placing the EVD can also lead to blockage of the tube. On average, correct placement occurs in nearly 68.58% of the cases. The cost of the EVD procedure is roughly $200, with additional costs for special equipment. Common issues include the tube being blocked by things like air and blood, which leads to inaccurate measurements of brain pressure. Other issues can include injury to blood vessels, a buildup of air in the brain, and accidental breaking or pulling of the tube.
Leaking cerebrospinal fluid (fluid around the brain and spinal cord), frequent sampling of this fluid, longer duration of tube insertion, and frequently changing the tube can all increase the risk of infection. To reduce this risk, it’s crucial to apply best practices for taking care of the EVD. For instance, it’s suggested to remove the tube as fast as possible, typically within 24 hours, when it’s no longer needed. Moreover, coated tubes, which have been treated with antibiotics, may reduce the risk of infection by around 20%.
It’s also noted that the outcome doesn’t really depend on whether the EVD is placed in the operating room or at the patient’s bedside, or on the experience of the surgeon. Whether the EVD is placed in the front or back of the head doesn’t seem to alter the risk of infection, either. New technologies, like augmented reality, can help place the EVD more accurately and improve the learning process for surgeons.
What Else Should I Know About Ventriculostomy?
Ventricular catheters are a tool doctors use to measure the pressure inside your brain, or intracranial pressure (ICP). This method is reliable, accurate, and cost-effective. An additional advantage is that it allows for the drainage of cerebrospinal fluid (CSF), the fluid that surrounds and protects your brain and spinal cord. This same catheter can also deliver medication directly to your brain, like antibiotics or clot-dissolving drugs.
One major benefit of this device is that it lets doctors remove some CSF if your brain pressure gets too high (around or above 20 mm Hg for 5 minutes or more). However, this comes with a downside: it’s not possible to both monitor the pressure and drain the fluid at the same time. The exact amount of CSF removed should be carefully adjusted based on the targeted pressure level (usually around 10 mm Hg) or guided by visual controls. Constant vigilance is vital to avoid any complications due to excessive fluid drainage.
The catheter can be removed once your brain pressure has been stable for at least two to three days. During this time, doctors will closely monitor your neurological function, such as movement skills, and adjust the catheter accordingly. The removal is a delicate process and needs to be performed with extreme care to prevent complications.
Even after removal, doctors will take thorough safety measures, such as clean procedures to prevent infection. Doctors will also lower the head end of the bed to reduce the risk of air accumulating inside your head (a condition called pneumocephalus). If your fever persists with symptoms of meningitis, they might send the tip of the catheter for lab analysis. After the closing of the wound, medical staff will closely monitor you for signs of worsening condition for at least 24 hours. They’ll also make preparations in case another catheter needs to be placed urgently.