Intracranial Hemorrhage: Subdural Hematoma and Subarachnoid Hemorrhage

00:01 Now let's talk about the clinical presentation, evaluation, and management of subdural hematomas. A subdural hematoma is a collection of blood below the inner layer of the dura but external to the brain and the arachnoid membrane. Subdural hematoma is the most common type of traumatic intracranial lesion and we typically see this result from falls, motor vehicle accidents, or some other type of trauma. Patients present with new onset of focal neurologic deficit with or without headache, often with headache, and symptoms tend to progress over time with deficits that worsen overtime after the trauma. We don't tend to see that lucid interval that we talked about with epidural hematomas, we see progressive decline in neurologic function. This can progress to impaired consciousness, loss of consciousness or coma in severe cases, patients may develop signs of increased intracranial pressure with nausea, vomiting, or headache and we can also see focal neurologic deficits early after that trauma. An evaluation of those focal neurologic deficits is critical. Patients who have stability of their neurologic deficit maybe managed conservatively but progressive neurologic deficit even minor or minimal deficits are indications for surgical intervention. So let's talk about the evaluation of subdural hematoma like all hemorrhages in the brain, non-contrast head CT is how we're going to evaluate these patients so you can see a non-contrast head CT of a typical subdural hemorrhage in this patient. They appear as crescent-shaped lesions that expand beyond the brain. This is a mass on the outside of the brain that is above the brain's surface. You can see the typical appearance of a hyperdense crescent-shaped lesion consistent with a subdural hematoma in this patient. Smaller subdurals can be managed without surgery but surgery may be needed for some of these patients. Subdural hematoma greater than 1 cm at the thickest point, generally require rapid surgical treatment either with drainage through a bolt or open craniotomy to evacuate that blood. Large craniotomy may be required to remove a thick blood clot and reach the side of bleeding and cauterize that area. Cerebral contusions may also be seen in patients who have suffered traumatic subdural hemorrhages and may or may not be removed at the time of surgery. Now let's talk about subarachnoid may not be removed at the time of surgery. Now let's talk about subarachnoid hemorrhage, and this is not only an intracranial hemorrhage, but it is a hemorrhagic stroke. Subarachnoid hemorrhages are considered within types of stroke, a hemorrhagic stroke. Subarachnoid hemorrhages present with rapid onset of life-threatening stroke symptoms caused by bleeding into the space surrounding the brain, that subarachnoid space. Subarachnoid hemorrhages may be caused by ruptured aneurysms, arteriovenous malformations, or trauma. And we consider each of those in patients presenting with a subarachnoid hemorrhage. 1/3 of patients will survive with good recovery, 1/3 will survive with disability, and 1/3 will die. And so we see 3 buckets of the typical clinical course with these patients and the goal was early intervention, early diagnosis, and early management to result in more favorable outcomes. What are the symptoms that we see in patients presenting with subarachnoid hemorrhage? Well patients typically present with sudden, severe headache and we call that a thunderclap headache. Patients describe the worst headache of their life and that really is defined by the speed of onset. Patients with sudden, severe or worst headache of their life beginning within seconds or is concerned for a thunderclap headache and should be worked up for subarachnoid hemorrhage. The headache can be more intense at the base of the skull. Patients typically describe this is the worst headache they have ever experienced and it begins suddenly, rapid onset within seconds, and may also be associated with symptoms of increased intracranial pressure. Headache, nausea, vomiting, photo or phonophobia resulting from irritation of the meninges as a result of blood in the subarachnoid space. What about the evaluation? We evaluate subarachnoid hemorrhage like any other hemorrhage in the brain with a non-contrast head CT, and here we see the typical findings of blood hyperdense signal within the subarachnoid space and you can see it lining up those spaces between the Circle of Willis expanding out into the ACA territory and the MCA territories along those blood vessels, which is typical of a subarachnoid hemorrhage. We often follow that with a CTA, CT angiography, to evaluate for an intracranial aneurysm which should be considered in any patient presenting with subarachnoid hemorrhage regardless of what a trauma was a part of their clinical presentation. And then whether about the treatment? When we manage aneurysms if that's the cause of subarachnoid hemorrhage with coiling or clipping and occasionally stenting of those aneurysms. We also need to manage secondary complications as a result of having blood in the subarachnoid space, the blood vessels of the brain, the arteries travel in that subarachnoid space. Blood is an irritant and can result in vasospasm and that's managed with triple H therapy, increasing blood pressure, increasing volume, and vaso or veno arterio dilating. Nimodipine is a medication used for vasodilation. We consider induced hypertension raising blood pressure to drive those blood vessels open as well as hypervolemia and hemodilution through increased in vigorous IV fluids. Now let's talk about the 4th type of hemorrhage. intraparenchymal