Cerebral Hemorrhage

CONTINUING EDUCATION FROM EMS

     This CE activity is approved by EMS Magazine, an organization accredited by the Continuing Education Coordinating Board for Emergency Medical Services (CECBEMS), for 1.5 CEUs.

To earn your credits, sign up for this RapidCE course online or log in to your account directly at www.rapidce.com. Or, to print and mail a copy, download the test here. The deadline to take this test is June 30, 2009.

OBJECTIVES

• Review the anatomy of the brain
• Discuss intracranial hemorrhage
• Discuss subarachnoid hemorrhage
• Review prehospital treatment of cerebral hemorrhage

     Unit 6 responds to a call where law enforcement report that the patient was involved in an argument that turned into an assault. During the assault, witnesses saw the adult male being hit in the head and face several times with a baseball bat.

     The EMS crew finds a male patient in his mid-30s lying on the ground, unconscious, with snoring respirations. They perform a rapid assessment and note the following: The patient is unconscious with respirations of 10, a labored heart rate of 110 and a strong radial pulse. Assessment of the head reveals obvious deformity to the patient's face, with blood coming from the nose, mouth and ears. The EMS crew recognizes the patient's critical status and prepares for urgent treatment and transport.

     The patient's neck, chest, abdomen, pelvis and extremities do not appear to have been injured. His skin is dry, pale and cool to touch. Reassessment of vital signs reveals snoring respirations of 12, EKG sinus tachycardia at 112, blood pressure of 190/110. The patient's pupils are dilated, unequal and slow to react. Pulse oximetry readings are 80% and the GCS is 6.

     The crew immobilizes the patient and applies high-flow supplemental oxygen. Intravenous access is established and an oral airway is successfully placed. En route to the local trauma center, the patient's ventilations are supported via bag-valve mask. Vital signs remain unchanged.

     Upon arrival at the emergency department, the patient is assessed by the trauma team. The only change noted in his condition is that the respiratory rate is now at 8 and shallow. The ED staff prepares for immediate intubation while performing a rapid trauma assessment. It is later determined that the patient sustained an epidural hematoma, in addition to numerous facial fractures. The prognosis is fair, and he will require numerous surgeries.

INTRODUCTION

     The brain is the focal point of the body and influences all other systems. When the brain functions effectively, a balance, or homeostasis, is achieved. When cerebral activity is impaired, such as in the opening case scenario, the balance is disrupted. A cerebral insult can be profound and may prove to be challenging to assess and manage in the prehospital setting. This article provides an overview of cerebral anatomy, focusing on some of the more common forms of cerebral hemorrhage.

ANATOMY

SKULL & MENINGES

     The skull contains the brain, spinal cord and blood vessels and is covered by skin, fat and periosteum. Just beneath the skull, but above the brain, is a protective lining called the meninges.

     The meninges consists of three layers: dura (outermost), arachnoid (middle) and pia (innermost).^1–5 The dura is relatively thick and fibrous and is tightly attached to the inner side of the skull. A gap between the skull and dura is referred to as the epidural space, which contains meningeal arteries. Hemorrhage in this location is referred to as an epidural hematoma. The arachnoid mater is located beneath the dura and has an appearance similar to a spiderweb. It is not vascular and does not include nerves. The subdural space separates the arachnoid and dura layers and is filled with cerebral spinal fluid (CSF). CSF is produced within the cerebral ventricles, circulates through the ventricular system and exits through small channels located near the brain stem. The pia layer covering the brain consists of small arteries.^1–5

THE BRAIN

     The brain is responsible for voluntary and involuntary body functions (see Figure 1). It consumes about 20% of the oxygen used by the body. The brain has limited capacity to store oxygen and is vulnerable to ischemia. Interruptions in cerebral blood flow can have significant effects. The carotid and vertebral arteries provide the majority of blood flow to the brain. Numerous mechanisms, including carotid sinus pressure, mean arterial pressure and carbon dioxide, support optimal cerebral circulation and function.^1–6

     The brain includes the cerebrum, cerebellum and brain stem. Insult or injury to these components can result in a variety of complications, including altered motor control, abnormal behavior or speech and impaired sensation.^1–6

     The cerebrum controls conscious behavior and voluntary movement. The cerebellum influences skeletal musculature involved with coordination, movement and equilibrium.^1,2 The brain stem includes the midbrain, pons and medulla oblongata and influences cardiac and respiratory functions.^{1, 2} In the opening scenario, the providers suspected potential brain stem involvement due to the patient's decreasing respiratory status.

     The brain components complement each other and support the overall goal of homeostasis. When this balance is interrupted, the individual may experience a variety of symptoms. By having a working knowledge of the basic pathology involved in certain cerebral hemorrhages, EMS providers will be better prepared to respond to and manage these cases. Following is an overview of intracranial hemorrhages, including subdural, subarachnoid and epidural hematomas.

CEREBRAL HEMORRHAGES

INTRACRANIAL HEMORRHAGE

     An intracranial hemorrhage (ICH) is the accumulation of blood within the brain. It may be localized or diffuse. Examples of ICH include subarachnoid hemorrhage, subdural hematoma and epidural hematoma. The development of an ICH can lead to cerebral edema and increased intracranial pressure (ICP). If this occurs, compression and displacement of the brain may result in herniation and death.^2,5–7

     ICH occurs in approximately 7% of head trauma cases and accounts for more than 20,000 deaths annually. The incidence of ICH increases with age and doubles with each decade over age 55. While these injuries can often be successfully managed, delays in care have been associated with less than optimal outcomes.^2,5–7

     Nontraumatic ICH most commonly results from hypertensive damage to blood vessel walls (e.g., hypertension, eclampsia, drug abuse), but it may also be due to autoregulatory dysfunction with excessive cerebral blood flow (e.g., reperfusion injury), rupture of an aneurysm or arteriovenous malformation (AVM), altered hemostasis (e.g., thrombolysis, anticoagulation) or venous flow obstruction (e.g., cerebral venous thrombosis).^2,5–7 The risk for aneurismal ICH increases with age, with most cases occurring between ages 40–60. Nontraumatic hemorrhage in children and adolescents is more likely secondary to AVM.⁸

     In the prehospital setting, symptoms associated with ICH range from mild headache to altered mental status, seizures or coma. Progression can occur within minutes of initial onset. Nausea and vomiting may occur, and anisocoria (unequal pupils) is sometimes present. Table I summarizes some of the more common symptoms.^2,5–7

SUBARACHNOID HEMORRHAGE

     A subarachnoid hemorrhage (SAH) involves blood within the subarachnoid space and can have traumatic or nontraumatic causes. SAH is the most common intracranial bleed associated with trauma and often results from sudden movement of the brain across the rugged surface of the interior skull. Hemorrhage in the subarachnoid space can be diffuse, with symptoms that include headache, decreasing mental status and posturing.^2,5,6,9,10

     EMS providers should note that more than 10% of patients with SAHs die prior to arriving at an emergency department. It is therefore essential to carefully assess and monitor any patient who presents with SAH-like symptoms. Examples of SAH symptoms are summarized in Table I.^2,5,9,10

     In the prehospital setting, the classic presentation of a nontraumatic SAH is sudden onset of an unusual headache, which may be followed by syncope, altered mental status or seizure activity. The headache may be the only symptom, and there may be no other obvious findings when the patient is assessed. The onset of headache is frequently associated with activities like exercise or sexual intercourse. The incidence of SAH is reported between 6 and 25 per 100,000 individuals.² The rate tends to increase with age, and there is a genetic predisposition.^2,5,9,10

SUBDURAL HEMORRHAGE

     A subdural hemorrhage (SDH) involves formation of a blood clot (hematoma) below the inner layer of the dura, external to the brain and arachnoid membrane (see Figure 2).^2,4 There are three basic types of SDH: acute, subacute and chronic. ^2,4 Acute SDHs are discovered within 14 days of injury; subacute SDHs are defined as being greater than 14 days old; chronic SDHs are much older and are often discovered incidentally on CT scan in the hospital setting. In any SDH, cerebral insult can occur from direct pressure, increased intracranial pressure or other cerebral events.^1–6

     SDHs are found in approximately 30% of severe head injuries in which a patient has a Glasgow Coma Scale score of 9 or less. Acute SDHs are associated with high morbidity and mortality rates. SDHs are more common in individuals over age 60, partially due to cerebral atrophy and anatomical changes. Bilateral SDHs are more common among infants.^1–6

     Suspect a possible SDH when moderate to severe blunt head trauma is reported. A loss of consciousness following the initial event may also be reported. In contrast to an acute SDH, where signs and symptoms tend to develop quickly, the symptoms associated with chronic SDH may be more challenging to recognize. In addition, the symptoms may be confused with other conditions such as dementia or alcohol intoxication. Chronic SDH symptoms may include an unexplained headache, personality change or hemiparesis/plegia. In the prehospital setting, classic chronic SDH findings may include altered mental status following a remote history of a head injury, such as in the case of an elderly patient or a patient who abuses alcohol and has frequent falls. Examples of SDH symptoms are summarized in Table I.^1–6

EPIDURAL HEMATOMA

     An epidural hematoma develops when there is excessive blood between the skull and the dura mater (see Figure 3). Several events occur in an EDH. First, there is a traumatic force, such as blunt trauma to the temporal bone on the skull. In many cases, the skull is fractured, lacerating a blood vessel. The resultant hemorrhage tends to be rapid because it often involves an artery, such as the middle meningeal artery. Venous bleeding involving vessels like meningeal veins or dural venous sinuses is also possible.^2,5,12–14

     Epidural hematoma is reported in as many as 2% of patients with severe head trauma. It is reported that 10%–20% of patients with traumatic coma may have an EDH. Mortality rates are reported to range between 5% and 50%.^2,5,12–14

     Following the initial injury, a majority of patients experience a loss of consciousness, often due to reticular activating system (RAS) disruption. In classic EDH, many patients then regain consciousness, referred to as a lucid interval, followed by a second loss of consciousness.

     While the previous sequence of events tends to be classic for EDH, there are exceptions. For example, after the lucid interval, one-third of patients do not experience a secondary loss of consciousness. Also, of patients who initially lose consciousness immediately following a traumatic event, one-third do not regain consciousness.^2,5,12-15

     Regardless of the nature of the hemorrhage, expansion of an epidural hematoma is possible. As a result of this, the patient may experience additional complications, such as intracranial hypertension and herniation.^2,5,12–14 The patient may develop opposite-side muscle weakness (50%), paralysis and same-side papillary dilation (fewer than 50%). EMS providers must carefully monitor the patient's status to avoid being lulled into a sense of complacency. Patients with an EDH can appear quite normal during the lucid interval, despite having a potentially fatal injury. Additional signs and symptoms are presented in Table I.^2,5,12–15

PREHOSPITAL ASSESSMENT

     Treatment provided in the prehospital setting will be influenced by a variety of factors not limited to the patient's overall condition, medical history, provider discretion, local protocol and proximity to the receiving facility. The first priority is to always ensure that the scene is secure. Once that is done, patient assessment and treatment can begin.

     Start the patient assessment as as you approach the patient. By observing the patient's behavior, you can form an initial impression. For example, does the patient appear to be conscious and coherent, or is he on the floor with sonorous respirations? If the patient is ambulatory, is his gait balanced or does he appear to be having difficulty? If he is speaking, is his speech clear or slurred?^2,5,16,17

     The patient may present with a variety of symptoms, depending on the injury. For example, the initial complaint may be headache, altered mental status, combative behavior, seizure, suspected cerebral vascular accident or head trauma. Intracranial hemorrhage should be considered in these situations. It is crucial to perform a thorough assessment, including obtaining a medical history if possible.^2,5,16,17

     Once physical contact is made with the patient, several components of the assessment can be quickly determined. For example, is the skin warm, pink and dry, or is it cool, pale and moist? Assess for the presence of a radial pulse. What is the quality and rate? When speaking with the patient, does he appear to be alert or does he have an altered level of consciousness?

     When assessing a patient suspected of having a cerebral hemorrhage, providers should perform a rapid neurological assessment. This can be accomplished using the AVPU method: A=patient is alert, V=responsive to verbal stimuli, P=responsive to painful stimuli, U=unresponsive.^2,5,16–18 This can also provide a very valuable baseline assessment of the patient's neurological status to pass on to hospital personnel, as this information can prove very useful in the early treatment and management of these patients.^2,5,16–18

     As part of the physical assessment, determine the patient's baseline Glasgow Coma Scale rating, which is based on eye, verbal and motor responses. Each category has a scale that allows for ranking the patient's best response. The lowest score is 3 (e.g., unconscious and unresponsive); the highest score is 15 (e.g., responsive and following commands). Table II provides details of the GCS. After the patient's baseline GCS has been determined, it should be reassessed throughout the patient's care. Changes in GCS, which may indicate a change in the patient's status, should be reported to the hospital's healthcare team so the information can be incorporated into the overall treatment plan.^2,5,16–18

     Assess the patient's pupils, noting their initial status, as well as any changes. For example, if the pupils were initially equal and round but are now dilated with a deviated gaze, this change is important and should be noted and relayed to the receiving facility.^2,5,16–18

     Obtain an initial set of vital signs as soon as possible and reassess every 5 to 10 minutes during transport. When assessing the heart rate, note the presence of bradycardia, tachycardia and any irregularities or changes. Depending on the nature and location of the cerebral hemorrhage, the patient may present with a variety of heart rates. Because ICP may lead to hypertension, monitor the blood pressure and note any changes. Respirations, including their pattern, should be noted. The presence of certain respiratory patterns, such as Cheyne-Stokes respirations, should raise concern. Cheyne-Stokes respirations are characterized by periods of breathing with fluctuating tidal volumes and periods of apnea.

     The presence of Cushing's triad, which is characterized by hypertension, bradycardia and irregular respirations, should be a signal that the patient may be experiencing a cerebral hemorrhage. Ominous vital signs in a patient with a suspected cerebral hemorrhage include hypotension, bradycardia and hypoventilation. If available, apply pulse oximetry and cardiac monitoring and include those findings in the vital signs.^2,5,16–18

     Obtain the patient's medical history whenever possible, which may include interviewing family members or friends. Examples of questions to ask include: What was the patient doing prior to the onset of symptoms? When did the symptoms start? What were the initial symptoms and what is the patient currently experiencing? What is the patient's chief complaint? Has he experienced similar episodes in the past? Has the patient consumed any food or liquids, including medications or alcohol? If the patient is taking medications, what are they? Is the patient compliant with his medications? Have alcohol or drugs been ingested? If so, what type and how long ago? Ask about risk factors. Certain underlying medical conditions, such as hemophilia or alcohol abuse, may have a significant impact on hospital management of these patients.^2,5,16–18

     It is important to document assessment findings. When possible, note the patient's baseline status and update the documentation following each reassessment. The receiving facility should also be provided with relevant assessment findings. When possible, provide reports in a consistent and clear manner.

PREHOSPITAL TREATMENT

     Managing the patient with a suspected cerebral hemorrhage can be challenging. Following is an overview of treatment options to consider. In addition to the treatments mentioned in this discussion, providers are encouraged to consult with their local protocols and medical directors for specific approaches in their systems.^2,5,16–18

     Managing the ABCs should always be a priority. The patient's airway should be managed in accordance with local protocols, ranging from observation to endotracheal intubation. Note that while BLS procedures, such as head-tilt/chin-lift or jaw thrusts, are generally accepted while maintaining immobilization, other procedures may not be advocated in all systems.^2,5

     Prehospital endotracheal intubation, including rapid sequence and nasotracheal intubation in the presence of a suspected cerebral hemorrhage, has been debated extensively in the medical literature. Providers are encouraged to consult with their local protocols regarding their system's policy on intubation. ^2,5,16–18

     Recent literature supports the philosophy that significant extension of scene times to manage the airway is not beneficial and may result in worse outcomes. As in all trauma situations, providers need to be mindful of minimizing scene times and strongly consider performing necessary procedures en route to the hospital.

     The patient's respiratory rate and effort should be assessed and managed as needed. Administer supplemental oxygen to any patient suspected of experiencing a cerebral hemorrhage. Remember that a priority in managing patients with a possible cerebral hemorrhage is to avoid hypoxia or anoxia. When possible, it is recommended that you achieve oxygen saturation greater than 90%. Oxygen liter flow and route of delivery should follow local protocols.^2,5,16–19

     Manually hyperventilating a patient suspected of having a cerebral hemorrhage, including head trauma, is the subject of significant debate.² It has long been taught that hyperventilation will induce hypocapnea, and cerebral vasoconstriction will occur, which may lead to a decrease in cerebral blood flow and reduce ICP. Contemporary research questions the efficacy of this practice,² as hyperventilation can lead to overconstriction of cerebral blood vessels, which may significantly decrease intracranial blood flow and lead to potentially worse outcomes.¹⁶ It is suggested that hyperventilation be reserved for certain clinical findings. For example, suspected cerebral herniation characterized by posturing and a fixed, dilated (blown) pupil may be a key indicator that hyperventilation should be considered. In such cases, adequate lung inflation and preventing hypoventilation (PaCO₂ >35 mmHg) is recommended.^2,16,17 If hyperventilation is pursued, a manual ventilatory rate of 20 is considered hyperventilation for an adult, a rate of 30 for children and 35–40 for infants.¹⁸ In the hospital setting, hyperventilation is likely to be guided by assessments such as ICP measurements and comprehensive neurological assessments.^2,5,16–18

     If intubation is performed, use capnometry or capnography if available. In an intubated patient, capnometry measures the end-tidal partial pressure of carbon dioxide (PetCO₂) with each exhalation. Capnometry of 35–45 mmHg is consistent with tracheal placement of the endotracheal tube and adequate ventilation. Capnography provides a waveform measurement of carbon dioxide. Both capnometry and capnography can be used to guide ventilation rates and prevent unintentional hyperventilation that would be detrimental to the head- injured patient. Consult local protocols regarding the application and use of end-tidal CO₂ monitoring.^2,20

     Establish intravenous access, which can serve as a route for medication or fluid administration, depending on the situation and the patient's overall condition. In the setting of a possible cerebral hemorrhage, avoid hypotension, as it can negatively influence the patient's outcome.^2,21 There are numerous discussions regarding the use and amount of intravenous fluids when a cerebral hemorrhage may exist. Fluid options range from hypertonic solutions to boluses of normal saline. As a general rule, intravenous access should be obtained and fluid infusion kept to a minimum in patients at risk for ICH, unless otherwise indicated, such as in multi-system trauma with hypotension. Providers should be familiar with local protocols regarding fluid selection and quantity to be administered.^{2,5,16–18,21}

     Similar to other scenarios, administration of medications will depend on a number of factors. For example, if hypoglycemia is present, administer dextrose. Seizure activity may be treated with anti-convulsant medications, particularly benzodiazepines. If an increased ICP is suspected, it may be an indication for mannitol or barbiturates where available. Consider lidocaine when endotracheal intubation is to be performed in the setting of increased ICP.^2,5,16–18

     Patient positioning in the presence of a suspected cerebral hemorrhage may have few options aside from supine, especially if trauma is suspected. In some systems, it may be acceptable to elevate the patient's head 30° in an effort to assist with reducing ICP; however, this may not be possible in the prehospital setting. If it is determined that an immobilized patient's head should be elevated, consider placing a blanket roll (or other like object) under the head of the longboard.^2,5,19

     EMS providers are encouraged to maintain the patient's body temperature and avoid letting the patient shiver or become overheated. In trauma settings, when clothing is removed and IV fluids administered, hypothermia can be induced. While ongoing research is looking closely at the potential benefit of hypothermia in the head-injured or stroke patient, intentionally inducing hypothermia in the prehospital setting is not an agreed-upon standard and should be avoided.^2,5,16–18

     The use of restraints, physical or chemical, may be indicated in a scenario involving a potential cerebral hemorrhage. In these situations, restraints may be used to help minimize patient movement or to assist efforts to protect the patient from additional injury. If restraints are used, clearly document the methods of restraint selected and the reason restraint was necessary. Frequent reassessment of the patient's overall status is critical.^2,5,16–18

     The presence of multi-system trauma can complicate management of the patient with a suspected cerebral hemorrhage. Providers will need to address the cerebral events in addition to other injuries. In these cases, aggressive fluid resuscitation may be needed in addition to ensuring that the patient's ABCs are secured. Oxygen administration will be essential to helping avoid hypoxia. The use of additional medications, whether related to chemical paralysis or as an adjunct in managing ICP, will be guided by a variety of factors, including the patient's overall condition and proximity to the receiving facility.^2,5,16–19

     Regardless of the assessment or treatment provided, complications are possible. Examples include elevated ICP, brain stem herniation, cerebral edema, new or recurrent hemorrhages, infection and seizures. While it may not be possible to identify the exact nature of the cerebral event in the prehospital setting, it is important to document any patient findings. These may assist with long-term management of the patient, aid in determining prognosis and developing long-term plans, and may help to reduce the occurrence of complications.^2,5,17

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     19. Hartl R, Gerber L, Iacono L, et al. Direct transport reduces mortality from brain Injury. The Journal of Trauma: Injury, Infection, and Critical Care, 2006.

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     Paul Murphy, MA, MSHA, EMT-P, has clinical and administrative experience in healthcare organizations.

     Chris Colwell, MD, is medical director for the Denver Paramedic Division and Denver Fire Department, as well as an attending physician in the emergency department at Denver Health Medical Center.

     Gilbert Pineda, MD, FACEP, is medical director for the Aurora Fire Department and Rural Metro Ambulance (Aurora, CO), as well as an attending physician in the emergency department at The Medical Center of Aurora and Denver Health Medical Center.

     Tamara Bryan, BS, EMT-P, has more than a decade of healthcare experience, including clinical and project management roles.