03.05 Brain Tumors

In this lesson we’re going to talk about brain tumors. Now, brain tumors can originate anywhere in the brain and there are multiple forms, like a glioblastoma or meningioma. For this lesson we’re going to give you the general things you need to know to understand what’s going on in a patient with a brain tumor.


Just like a tumor anywhere else in the body, a brain tumor is an overgrowth of cells that develop into a mass. As I said before brain tumors can be found anywhere in the brain. They can be benign which means they're non-cancerous or they could be malignant which means they're cancerous. Cancerous tumors are either primary or secondary. Primary tumors begin and grow within the brain itself. Secondary tumors originate elsewhere in the body and metastasize to the brain, creating a new mass. Risk factors for brain tumors include genetics and or environment as well as exposure to radiation and previous head injuries. As you can see in the cross-sections of this MRI, brain tumors can take up quite a bit of space both left to right and top to bottom.


So that's where the problem comes in with these tumors. If you remember from the intracranial pressure lesson when we talked about the Monro Kellie hypothesis, any space occupying lesion is going to cause compression on the brain tissue and an increased ICP because the skull is a fixed box and there's nowhere else for it to go. With that increased pressure within the skull, almost all brain tumors will show some common symptoms like headaches, seizures, and altered mental status. The rest of the symptoms are going to be specific to where the tumor is growing. Wherever it grows, that is where it starts to put pressure on that brain tissue locally. So each tumor may present with a different set of symptoms.


Each area of the brain controls a different aspect of neurologic function. If a tumor is in the frontal lobe, putting pressure on that brain tissue, we will see things like motor issues, mood and personality issues, and memory problems. As the tumor gets closer to the temporal lobe, we may see hearing loss or tinnitus as well as some difficulty producing speech because of Broca's area. The parietal lobe controls the majority of our sensory perception, so we will see sensory issues as well as more speech issues, both in producing and understanding speech. In the occipital lobe we will see vision changes as well as difficulty controlling eye movement. And since we know the cerebellum is responsible for balance, we will see patients possibly falling more or having coordination issues as well as some nausea and vomiting. And then finally the brainstem is responsible for the majority of our core functions within the body, so if we have a tumor on the brain stem will see issues with temperature regulation, respirations, and other symptoms related to altered sympathetic nervous system activity. These brain tumors can grow for quite a while before symptoms begin to present. Some of these symptoms like mood changes or forgetfulness or a little bit of hearing loss can actually be written off by patients and family members at times because they're such general symptoms. Sometimes it's not until something severe happens that patients are even brought in to get checked out, and by then the tumor could have grown significantly.


Now the most dangerous complications with brain tumors arise because of the increasing intracranial pressure within the skull due to this growing mass. One of those complications is seizures, so we will put our patients on seizure precautions. We will pad the side rails, give antiepileptic drugs, and possibly keep Ativan at the bedside for safety. Patients also have a risk for herniation, because when you have a mass growing here in your skull it is Shifting and moving and compressing all of this brain tissue, which can cause it to potentially herniate in various directions. The other problem with this growing intracranial pressure within the skull is that often times it puts pressure on the pituitary gland that you see here, and can potentially cause damage. One of the hormones affected is antidiuretic hormone or ADH. With pituitary damage, we lose the secretion of antidiuretic hormone. When that happens we see massive diuresis, the patient will put out liters and liters of extremely dilute urine that's basically just water. This is known as diabetes insipidus. Check out the lesson on diabetes insipidus in the metabolic endocrine course to learn more. Just know that it is something we need to be watching out for.


So when a patient presents with these neuro changes, We will work to rule out other possible causes of the symptoms like infection or stroke. We will typically get a CT scan first, and then an MRI if we see anything that needs to be explored further. If they do find something they will typically also scan the chest, abdomen, and pelvis to look for other tumors that could be the primary source. Then, we’ll get a biopsy of the tumor if possible to confirm. Of course patients with malignant tumors will likely be on chemotherapy and radiation. But all patients will be on antiepileptic drugs like Dilantin and Keppra, they'll be on corticosteroids to decrease inflammation, and antiemetics for any nausea associated with the tumor or with chemotherapy.


The other option we have for brain tumors is to physically open the skull and remove the tumor through a procedure called a craniotomy. You can see here they will cut away a piece of the skull, in order to access the tumor. Now this is not an option for all brain tumors because they aren’t all easily reached from the outside. For patients with non-surgical tumors, they will likely just receive chemotherapy and radiation. After the procedure, patients will likely still be intubated and sedated for airway protection. We will do frequent neuro checks, usually every hour for a while after surgery. Then we’ll do follow-up scans periodically after surgery to check for any bleeding or swelling and to make sure the surgeons didn't miss any part of the tumor.


Priority nursing concepts for a patient with a brain tumor include intracranial regulation, cognition, and possibly end of life and coping. As nurses we’re responsible for closely monitoring their neuro status for any changes and helping to minimize their intracranial pressure. Review the ICP lesson for detailed interventions. Many patients with brain tumors have significant changes in their personality, functional ability, or ability to communicate. This can be a struggle for both the patient and their family. It's also important to note that some brain tumors like glioblastoma have a very high mortality rate. So as nurses we make sure we help patients and their families through these difficult times.


So remember that brain tumors are abnormal growth of cells that will grow and compress brain tissue wherever they are. Because they can be anywhere in the brain, symptoms will vary based on the size of the tumor and where it's growing. Many brain tumors have high mortality rates, and many will leave patients with significant deficits. Possible complications like seizures, diabetes insipidus, and brain herniation can cause anything from speech issues, all the way to brain death. If there's increased ICP or any brainstem involvement, there can be problems with airway and breathing. So we prioritize our ABCs, we put patients on seizure precautions, and we do frequent neuro checks so that we can catch any neuro changes, even if they're subtle.


So those are the most important things you need to know about brain tumors. Of course if you end up working on a neuro or oncology floor, you will learn much more detail. Make sure you check out the care plan attached to this lesson for more detailed nursing interventions and rationales. Now go out and be your best selves today, and as always, happy nursing!