Prehospital Academy Lesson 18.2
Neurologic Emergencies: Altered Mental Status (EMT)
This lesson continues our neurological series by focusing on altered mental status (AMS), one of the most common and challenging complaints encountered in EMS. AMS describes a patient who isn't thinking clearly, is unable to be aroused or awakened, or exhibits a decreased level of responsiveness. It is a sign of an underlying medical condition or injury and requires a systematic approach to assessment and management to identify and address the cause.
Defining Altered Mental Status
Altered mental status is not a diagnosis itself but rather a symptom indicating a change in a patient's brain function. It can manifest in various ways:
Confusion: Disorientation to person, place, time, or event.
Lethargy: Drowsiness, but easily aroused.
Obtundation: Difficult to arouse, responds slowly or minimally to stimuli.
Stupor: Responds only to vigorous and repeated painful stimuli.
Coma: Unresponsive to all stimuli.
Aside from stroke and seizure, AMS is a prevalent neurological emergency, often signaling a critical underlying issue.
Causes of Altered Mental Status: AEIOU TIPS
The mnemonic AEIOU TIPS is a valuable tool for EMTs to recall common causes of altered mental status:
A - Alcohol: Intoxication or withdrawal.
E - Epilepsy: Seizures (postictal state or status epilepticus).
I - Insulin: Hypoglycemia (low blood sugar) or hyperglycemia (high blood sugar).
O - Overdose: Of drugs (prescribed or illicit) or accidental poisonings.
U - Uremia: Kidney failure.
T - Trauma: Head injuries, internal bleeding.
I - Infection: Sepsis, meningitis, encephalitis.
P - Psychogenic: Psychological conditions (though rule out organic causes first).
S - Stroke: Ischemic or hemorrhagic stroke.
Other less common but significant causes include hypothermia/hyperthermia, hypoxia, and electrolyte imbalances.
Assessment of Altered Mental Status
A systematic assessment is crucial:
Primary Assessment: Always begin with ABCs. A compromised mental status can quickly lead to airway compromise.
Level of Consciousness (LOC) - AVPU Scale:
A - Alert: Patient is awake and oriented.
V - Verbal: Patient responds to verbal stimuli.
P - Pain: Patient responds to painful stimuli.
U - Unresponsive: Patient does not respond to any stimuli.
Orientation: Assess if the patient is oriented to person, place, time, and event. This helps gauge their cognitive function.
Pupil Assessment: Size, equality, and reactivity to light. Unequal or non-reactive pupils can indicate neurological damage.
Glasgow Coma Scale (GCS): A more detailed assessment tool that scores eye opening, verbal response, and motor response. (While basic EMTs may not calculate GCS routinely, understanding its components is beneficial).
Vital Signs: Look for abnormal patterns in respirations, heart rate, and blood pressure.
Blood Glucose Level (BGL): A critical assessment, especially for diabetic patients. Obtain BGL quickly for any AMS patient.
AMPLE History: Ask about Allergies, Medications, Past medical history, Last oral intake, Events leading to the illness/injury. Crucial for identifying the underlying cause.
Management of Altered Mental Status
Management focuses on supportive care and addressing the underlying cause if identifiable:
Airway Management: Maintain a patent airway, especially in unresponsive patients. Consider airway adjuncts (OPA/NPA) or position the patient in the recovery position. Be prepared to suction.
Oxygenation and Ventilation: Administer high-flow oxygen. Assist ventilations with a BVM if breathing is inadequate.
Circulation: Monitor pulse and blood pressure. Treat for shock if indicated.
Glucose Administration: If hypoglycemia is present and the patient is unable to self-administer, administer oral glucose (if patient is conscious and can swallow) or assist with glucagon (AEMT/Paramedic scope).
Seizure Management: Protect the patient from injury, loosen restrictive clothing, and time the seizure.
Stroke Protocol: If stroke is suspected, follow local protocols for rapid identification and transport to a stroke center.
Temperature Regulation: Prevent hypothermia or hyperthermia.
Reassessment: Continuously monitor the patient's mental status and vital signs, and be prepared for changes.
Critical Thinking Questions
You are called to an unresponsive patient. After ensuring a patent airway and adequate breathing, what is your next immediate assessment priority, and why is it crucial for determining the patient's condition?
A patient who is awake but confused has a blood glucose level of 45 mg/dL. What immediate intervention would you perform, and what are the contraindications for this intervention?
Distinguish between a patient who is "lethargic" and one who is in a "stuporous" state according to the AVPU scale. How would your verbal and painful stimuli differ when assessing these two levels of consciousness?
You respond to a patient with an altered mental status who smells strongly of alcohol. Discuss why it is critical NOT to assume alcohol intoxication as the sole cause of AMS without a thorough assessment for other underlying conditions.
A patient with AMS has unequal and sluggishly reactive pupils. What part of the central nervous system does this finding potentially indicate damage to, and how does this affect your overall patient management strategy?