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The medical team will designate an appropriate head injury assessment location for each venue. The head injury assessment location shall be a quiet location which will remove the athlete from the chaotic competition environment and permit medical personnel to conduct a thorough head injury assessment without outside distractions. Athletes who present with signs and symptoms consistent with a concussion will be entered into the the team’s concussion protocol. Athletes entering into the concussion protocol will receive a Head Injury Warning Sheet with specific guidelines for seeking care when not in the presence of team medical personnel. The Head Injury Warning Sheet will be reviewed with the athlete and also with a family member or designated guardian. Athletes who present with signs and symptoms inconsistent with a concussion will be assumed to have suffered injury resulting in intracranial hemorrhage and will be immediately transported to an appropriate medical facility by EMS.
Distinguishing Intracranial Hemorrhage (IH) from a sports-related SRC (SRC) has long been a challenge for medical teams during sideline management of athletes having suffered head trauma. IH and SRC can present with very similar acute signs and symptoms, but each requires very different acute management. While proper management of both conditions is critical to prevent a catastrophic outcome, failure to identify an acute IH could result in rapid deterioration of the athlete’s health due to life-threatening elevations in intracranial pressure (ICP) 1,2. Elevated ICP has been shown to result in specific sign and symptom patterns that may be useful in helping athletic trainers distinguish IH from SRC. Therefore, this section discusses 1) how IH may result in elevated ICP, 2) specific signs and symptoms that evolve as ICP rises, 3) how serial monitoring of specific signs and symptoms may be useful in identifying rising ICP, and 4) a possible sideline assessment protocol using Sports Medicine Concepts’ Mild Traumatic Brain Injury (MTBi) Differential Diagnosis Trending Report (DDTR). The medical team will use differential diagnosis trending as part of an overall assessment strategy to help determine if an injured athlete should be transported to an appropriate medical facility or be entered into the team’s concussion protocol.
Body’s Response to Rising ICP
The cranial compartment, vertebral canal, and dura form a rigid inelastic container that houses the brain, blood, and cerebral spinal fluid (CSF). ICP is the pressure inside the cranial compartment. Under normal conditions autoregulatory processes maintain pressure within the cranial compartment to within 1 mmHg 3. Rising ICP results from volume changes in the brain, CSF, or blood. In order to maintain ICP, an increase in the volume of one of the cranial constituents must be offset by a compensatory decrease in volume of another. For example, an IH resulting in an increase blood volume within the cranial compartment is compensated for by displacement of CSF into the ventricles and spinal canal, and some elasticity properties of the brain. This compensatory mechanism allows for small increases in cranial volume that do not immediately result in elevated ICP 4,3.
Recognition of Rising ICP
Normal adult ICP is 7-15 mmHg 3. The body’s compensatory mechanism for controlling small increases in cranial compartment volume will accommodate pressures up to 25 mmHg. Therefore, initial increases in ICP may not result in any outward signs and symptoms that can be readily observed during acute sideline management. However, as ICP begins to reach mean arterial pressure (MAP) cerebral perfusion pressure (CPP) falls resulting in decreased blood flow to the brain. As a result of declining CPP the body’s autoregulatory processes increase systemic blood pressure in an attempt to maintain adequate blood flow to the brain. In the case of an IH, an increase in systemic blood pressure (BP) will facilitate bleeding into the cranial compartment, initiating a spiraling ICP-CPP-BP cycle that will ultimately result in elevated ICP that leads to ischemia and brain infarction secondary to inadequate blood flow to the brain 1,2,5.
As ICP exceeds the body’s compensatory mechanism an athlete is likely to begin exhibiting an increase in number and severity of signs and symptoms. Signs and symptoms indicative of rising ICP may include headache, nausea, vomiting without nausea, ocular palsies, altered levels of consciousness, back pain, papilledema, and widened pulse pressure. In children, bradycardia may be particularly suggestive of high ICP 6. Specific signs and symptoms indicating the presence of an IH include bradycardia, hypotension, hypertension, respiratory depression, systemic vasoconstriction, altered mental status or lucid interval, hyperventilation, sluggish dilated pupils, and widened pulse pressure. Early recognition of these signs and symptoms is paramount to ensure that injured athletes receive medical treatment before ICP reaches 40-50 mmHg, at which point catastrophic outcomes secondary to brain infarction and brain death become more likely 7.
Catastrophic outcomes may also result secondary to a mid-line shift of the brain within the cranial compartment. A mid-line shift may result over a period of time as IH results in a growing mass of blood that eventually pushes the brain from mid-line. If the mid-line shift results secondary to an IH, the on-set of signs and symptoms may develop over a period of time, depending on how long it takes for enough blood to collect in the cranial compartment to result in pushing the brain from mid-line. Signs and symptoms of a growing mass effect IH may include pupillary dilatation, abducens palsies, increased systemic blood pressure, bradycardia, irregular respiratory patterns, and a widen pulse pressure. Trauma, itself, may result in a mid-line shift. If the mid-line shift is a direct result of trauma, dire signs and symptoms may present immediately. Regardless of a gradual or immediate on-set, a resulting mid-line shift will ultimately lead to brain herniation or brain stem compression resulting in brain infarction and decrease respiratory drive 8.
An injury resulting in rapid increases in ICP or mid-line shift will present with immediately life-threatening outward signs and symptoms indicating the need for immediate transport. Injury to the brain resulting in more gradual rises in ICP may initially mimic a SRC. However, observation of certain sign and symptom trends could alert athletic trainers to the possibility of elevated ICP secondary to IH, and thus the need for immediate transport. Vital signs trending is an assessment strategy that has been used to observe serial measures of heart rate (HR), respirations (R), blood pressure (BP), and temperature (T) at 10min intervals over a 30 minute period. Vital signs that do not normalize within the 30 minute trending period warrant immediate medical follow-up 9. In the following section the vital signs trending philosophy is modified and used to observe for the development of specific signs and symptoms indicative of rising ICP secondary to IH, and thus, the need for immediate transport of an injured athlete. Specifically, the vital signs trending protocol was changed from 10 minute to 5 minute serial measures of certain signs and symptoms over a 30 minute period of time. This modification is believed to be more sensitive to changes in signs and symptoms. Many of the signs and symptoms that present themselves in the sideline environment that are the result of an IH, rising ICP, or mid-line shift may be readily observed by trending three specific assessment batteries; the Sport Concussion Assessment Tool (SCAT) Symptoms Severity Score 10, the Sports Medicine Concepts’ Cranial Nerve Assessment Survey (See Appendix A), and Cushing’s Triad, which compares heart rate, respiration, and pulse pressure. Therefore, these traditional indicators of SRC and elevated ICP were added to the vital signs trending protocol. A theoretical application of this trending approach is explained in detail below followed by Sports Medicine Concepts’ Mild Traumatic Brain Injury (MTBi) Differential Diagnosis Trending Report that offers a means of more efficiently applying this concept during sideline management. (Evidence Category C)
Symptom Severity Graph
Typical sideline assessment using the SCAT form includes assessment of 22 signs and symptoms for which athletes are instructed to rate their symptom severity at the time of evaluation. Athletes are given a severity score ranging from 0 points, if they are not experiencing the sign or symptom at all, and 6 points, indicating the sign or symptom is severe. The total number of signs and symptoms out of a possible 22 is placed on the ICP Symptom Score Trending Graph (See Figure 1). The symptom severity score is calculated by adding up the severity rating numbers. This number is plotted on the Symptom Severity Trending Graph (See Figure 2). If this process were repeated at 5 minute intervals for a total of 30 minutes, general trends indicating the possibility of rising ICP secondary to IH may become evident. Generally, athletes who may have sustained a head injury resulting in IH may present with an increasing number of signs and symptoms or an increasing symptom severity rating. A rapid rise in symptoms or symptom severity scores during the trending period may be indicative of rising ICP and the need to transport an athlete prior to the completion of the 30 minute trending period, particularly if the signs and symptoms involved include headache, nausea, or vomiting in the absence of nausea. Figures 1 and 2 illustrate a theoretical model of general trends in the number and severity of signs and symptoms that might be indicative rising ICP due to IH.
Another significant sign of IH that may be observed using the Symptom Score and Symptom Severity Trending Graphs is a lucid interval. A lucid interval is a period of time during which an athlete reports improvement in signs and symptoms followed by worsening signs and symptoms, including altered mental status (AMS). Figures 1 and 2 depict potential graphic representations of a lucid interval by illustrating a general trend of improvement followed by worsening severity scores. (Evidence Category C)
Cranial Nerve Assessment Graph
Although there is some overlap in the cranial nerve assessment survey with the SCAT Symptom Evaluation Form, specific assessment of all 12 cranial nerves is warranted because any rise in ICP could have immediate impact on any of the cranial nerves due to their anatomical location at the base of the brain within the cranial compartment. Therefore, assess both motor and sensory function for all 12 cranial nerves using SMC’s Cranial Nerve Assessment Survey provided in Table 1. Calculate the total number of abnormal findings out of a possible 12 and place this number on the Cranial Nerve Trending Graph shown in Figure 3. Repeat this assessment at 5 minute intervals for a total of 30 minutes. A general trend indicating a rise in the number of abnormal findings may indicate the presence of rising ICP due to IH, and the need for immediate transport of the injured athlete. More specifically, rising ICP has been shown to result in ocular palsies, papilledema, pupillary dilatation, and abducens palsies. These specific conditions may present themselves upon assessment of the Optic (II), Oculomotor (III), Trochlear (IV), and Abducens (VI) nerves. (Evidence Category C)
Table 1. SMC’s Cranial Nerve Assessment Survey.
|I||Olfactory||Smell||Have the athlete identify odors w/ each nostril(sports cream, antiseptic, etc)|
|II||Optic||Visual acuity||Have the athlete identify number of fingers|
|Visual field||Approach the athlete’s eyes from the side using your finger or light pen|
|III||Oculomotor||Pupilary reaction||Shine pen light in each eye and note pupilary reaction|
|IV||Trochlear||Eye movements||Have the athlete follow your pen light without moving his/her head|
|V||Trigeminal||Facial sensation||Have the athlete identify areas of face being touched|
|Motor||Have the athlete hold mouth open against resistance|
|VI||Abducens||Motor||Check athlete’s lateral eye movements|
|VII||Facial||Motor||Have the athlete smile, wrinkle forehead, frown, puff cheeks, and wink each eye|
|Sensory||Have the athlete identify familiar tastes (Gatorade)|
|VIII||Acoustic||Hearing||Have athlete identify sounds in both ears (tuning fork)|
|Balance||Check athlete’s balance (Romberg sign)|
|IX||Glossopharyngeal||Swallowing||Have the athlete say “ah” and swallow hard|
|X||Vagus||Gag reflex||Test the gag reflex (tongue depressor)|
|XI||Spinal||Neck strength||Have athlete complete full AROM, shoulder shrugs against resistance|
|XII||Hypoglossal||Tongue movement and strength||Have the athlete stick out his/her tongue and move it around. Apply resistance with tongue depressor.|
Cushing’s Triad is an assessment battery that compares pulse pressure, heart rate, and breathing patterns to indicate the presence of intracranial hemorrhage or edema. Pulse pressure, or the amount of pressure required to create the feeling of a pulse, is the mathematical difference between the systolic and diastolic pressure. For example, normal blood pressure is 120mmHg (systolic) / 80mmHg (diastolic), resulting in an normal healthy pulse pressure of P (systolic) – P (diastolic) = 40 mmHg. The normal resting pulse pressure of a healthy individual, sitting position, is about 60-80 mmHg 11. Pulse pressure, heart rate, and respiration rate will increase with exercise, but have all shown to trend towards normal within 10 minutes following the cessation of exercise. Therefore, an injured athlete presenting with an elevated pulse pressure, heart rate, or respiration rate should be trending towards normal within 10 minutes, and should certainly demonstrate a normal pulse pressure, heart rate, and respiration following a 30 minute trending period. (Evidence Category C)
To assess Cushing’s Triad, use a blood pressure monitor to measure blood pressure and heart rate. Additionally, assess the athlete’s respirations and respiration rate. Calculate pulse pressure and place the pulse pressure, heart rate, and respiration rate values on the Cushing’s Triad Trending Graph shown in Figure 4. Blood pressure of a normal healthy individual should trend toward 120mmHg (systolic) / 80mmHg (diastolic) resulting in a normal pulse pressure of 40-80mmHg. Respiration rates should trend toward 10-12 breaths per minute. A more sensitive measure of effective respiration may be obtained by using a simple finger pulse oximeter to measure blood oxygen saturation (SpO2). Normal range for SpO2 is typically considered from 95%-99%, but may be lower for individuals in high altitude environments 12. A general trend indicating an elevated pulse pressure combined with bradycardia and ineffective respirations might indicate the presence of IH or edema and the need for immediate transport of the injured athlete. Incidentally, a low pulse pressure may also be problematic in and of itself, indicating the presence of shock or significant blood loss. A pulse pressure is considered low if it is less than 25% of the systolic value 11.
SMC MTBi Differential Diagnosis Trending Report (DDTR)
The intent of the prior discussion was to graphically demonstrate how sign and symptom trends indicative of rising ICP secondary to IH may present. The DDTR is intended to offer athletic trainers an easier mechanism for applying this concept during on-field assessment of a potentially head injured athlete.
In the absence of immediate life-threatening signs and symptoms, begin recording information on the DDTR 10 minutes post-injury and continue to do so at 5 minute intervals. Clinical signs and symptoms that fail to normalize following the 30min trending period or that worsen significantly during any interval during the trending period may be indicative of rising ICP pressure secondary to IH or cerebral swelling.
Total Number of SCAT Symptoms and Symptom Severity Score
Using the SCAT Symptom Evaluation chart calculate the total number of SRC-like symptoms and the corresponding Symptom Severity Score. A significant increase in the number of SRC-like symptoms or the symptom severity score may be indicate the need to transport the athlete to the nearest Level 1 trauma center.
Altered Mental Status
Assess the athlete for any variations in level of consciousness or the presence of a lucid interval. Use “N” to indicate normal or “AB” to indicate abnormal findings.
Using the Sports Medicine Concepts, Inc., Cranial Nerve Assessment Survey record the number of abnormal clinical findings (out of a possible 12). An increase in the number of abnormal clinical findings during any interval or remaining abnormal findings following the 30 minute trending period may be indicative of the need to transport the athlete from the field to the nearest Level 1 trauma center.
Heart Rate, Blood Pressure, and Pulse-Pressure
Use an appropriate heart rate / blood pressure monitor to record the athlete’s heart rate, blood pressure, and pulse pressure (Systolic-Diastolic) readings. Persistent heart elevation above 100bpm, hypotension, hypertension, and pulse-pressures above 100 could be indicative of rising intra-cranial pressure, and the need to transport the athlete by EMS to the nearest Level 1 trauma center.
Blood Oxygen Saturation
Using a pulse-oximeter take serial measures of the athlete’s blood oxygen levels. Abnormal blood oxygen levels may be indicative of the need to transport the athlete by EMS to the nearest Level 1 trauma center.
Table 2. SMC’s MTBi Differential Diagnosis Trending Report (DDTR)
|MTBi Signs and Symptoms||Time: Status Post-Injury|
|10min S/P||15min S/P||20min S/P||25min S/P||30min S/P|
|Total number of SCAT symptoms|
|SCAT Symptom severity score|
Assessing pulse pressure, heart rate, respirations, abnormal cranial nerve finding, and signs and symptoms of SRC at 5 minutes intervals for a period of 30 minutes may provide medical personnel with a mechanism for sideline identification of head injuries that are more likely to involve rising ICP due to IH, and therefore, the need to immediately transport the injured athlete to an appropriate medical facility. It is important to note that vital signs trending as a sideline assessment tool is not without significant limitations. The presence of any of the signs and symptom patterns discussed in this section may suggest an increased potential for IH, but their absence does not rule out the possibility that an IH exists. Additionally, the trending graph results presented here represent only one example of sign and symptom patterns that result in a graphic form that may indicate the presence of an IH. Other trending patterns may produce other graphic forms also indicative of an IH. Therefore, medical personnel will consider this sideline evaluation protocol only as part of a comprehensive head injury management plan that includes a multi-disciplined emergency action plan. Annual EAP rehearsal will include discussions on the validity and reliability of the ICP Trending Graphs and the SMC DDTR as predictors of hematoma resulting from head trauma in sports.