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ALTERED LEVEL OF CONSCIOUSNESS

 

INTRODUCTION

Optimal patient care requires that the EMT-I understand common causes of altered level of consciousness.  The following topics will be discussed during this lesson:

 

·        Common causes of altered level of consciousness

 

·        Pathophysiology of common causes of altered level of consciousness (seizure, stroke, and syncope)

 

·        Assessment of the altered patient

 

·        Field management of the patients that are altered

 

·        Transportation decisions for altered patients

 

LESSON OBJECTIVES

At the end of this lesson the participants will be able to:

 

1.         Identify common causes of alteration in level of consciousness.

 

2.         Discuss the pathophysiology of common causes of altered level of consciousness (seizure, stroke, and syncope).

 

3.         Demonstrate field assessment of the altered patient.

 

4.         Verbalize field management of the altered patient.

 

5.         Discuss transport considerations for the altered patient.

 

SKILLS

Initial Assessment of the Altered Patient

Focused History and Detailed Physical Examination of the Altered Patient

 

KEY VOCABULARY 

The following terms will be used during this lesson:

 

·        A.L.O.C. - an abbreviation for altered level of consciousness

 

·        Aura - a sensation that precedes seizure activity (often a particular odor or vision)

 

·        Consciousness - awareness of self and environment

 

·        Cerebral vascular accident (CVA) - sudden change in neurologic status caused by an interference with blood supply to the brain

 

·        Epilepsy - a condition characterized by abnormal electrical impulses in the brain which result in seizures

 

·        Grand mal seizure - generalized tonic-clonic muscle contractions with a loss of consciousness

 

·        Hemiplegia - paralysis of one side of the body

 

·        Hypertensive encephalopathy - altered mental status caused by hypertension

 

·        Hypoxia - inadequate oxygen to the cells

 

·        Post-ictal - period of the altered level of consciousness following a seizure

 

·        Seizure - a temporary alteration in behavior caused by a massive electrical discharge in the brain

 

·        Status epilepticus - a seizure lasting longer than 10 minutes, repetitive seizures without periods of consciousness, or more than 3 seizures per hour

 

·        Syncope - brief (less than 30 minutes) loss of consciousness caused by inadequate brain perfusion

 

·        Transient ischemic attack (TIA) - temporary inadequate brain perfusion which results in neurological deficits and which completely resolves.

 

·        Vasovagal response - temporary stimulation of the vagus nerve which causes a drop in heart rate and reduction in cardiac output

 

KEY CONCEPTS

The following section provides information and space for taking notes on the key concepts discussed by the instructor.

 

ALTERED LEVEL OF CONSCIOUSNESS - OVERVIEW

Causes of altered level of consciousness

·        Structural:  brain lesions that destroy tissue or occupy space that is normally occupied by the brain

·          Epilepsy

·          Tumors

·          Trauma

·        Cardiovascular:  temporary or permanent interruption to the blood supply to the brain

·          Vasovagal response

·          CVA

·          TIA

·          Hypertensive encephalopathy

·          Shock

·          Dysrhythmias

·        Metabolic:  abnormally high or low levels of circulating metabolites

·          Hypoxia

·          Hypoglycemia

·          Hyperglycemia

·          Renal failure (uremia)

·          Liver failure

·          Infection (sepsis)

·        Environmental:  external factors that cause deterioration of central nervous system function

·          Overdose

·          Toxins

·        Behavioral: abnormal mental status that results from internal factors

·          Psychiatric disorders

 

 

Mnemonic for Causes of Altered Level of Consciousness

A - alcohol, acidosis, anoxia

E - epilepsy, environment

I - insulin (diabetes)

O - overdose

U - uremia (metabolic), underdose

 

T - trauma, toxins, tumors

I - infection (sepsis)

P - psychiatric disorders

S - stroke (CVA)

GOLDEN RULE: 

Altered level of consciousness is characteristic of nervous system dysfunction and warrants thorough examination to rule out all possible causes.
 

 

 

 

 

 

Seizure

Pathophysiology:  massive electrical discharge in the brain causes a temporary alteration in behavior

·        Causes of seizures

            A:        alcohol withdrawal

            E:        epilepsy

            I:         insulin

            O:        overdose

            U:        underdose

 

            T:        trauma

            I:         infection

            P:         psychiatric disorder

            S:         stroke

 

 

Signs and Symptoms of Seizures

Generalized seizures involve the entire cortex of the brain

·        Grand mal seizures

·          May have an aura

·          Loss of consciousness

·          Tonic-clonic movement

·          Incontinence

·          Clenched teeth, tongue biting

·          Post-ictal phase

 

·        Petit mal seizures

·          Loss of consciousness (10-30 seconds)

·          Eye or muscle fluttering

·          May lose muscle tone

 

Partial seizures are confined to a limited portion of the brain, however they may spread and become generalized

 

·        Focal seizures

·          Localized to one area of the body

·          No loss of consciousness

 

·        Psychomotor seizures

·          Characterized by distinctive auras (ie. metallic taste)

·          No loss of consciousness

·          May lose touch with their surroundings for a few moments

·          May have sudden, brief personality change

 

Field management of seizures:

BLS Procedures:

·          If actively seizing do not attempt to stop the seizure or push anything into their mouth to try to prevent them from biting their tongue

·          Do not attempt to control the seizure

·          Protect the seizing patient

·          Maintain their airway

·          High flow O2 by mask

·          Left lateral position

·          Spinal immobilize if trauma or unknown mechanism of injury

·          Assist with ALS procedures

 

ALS procedures

·          Advanced airway prn

·          Venous access

·          Glucometer

·          Monitor

·          Valium for active seizures

·          Dextrose for hypoglycemia

 

 

Syncope

Pathophysiology

·          A temporary interruption in cerebral blood flow results in a brief period of loss of consciousness (less than 30 minutes)

 

Causes of syncope

·          Cardiac dysrhythmias

·          Transient ischemic attacks

·          Vasovagal response

·          Orthostatic syncope (dehydration, medication effect)

·          Fainting (fever, prolonged standing in a warm crowded room, emotional distress)

·          Seizures

 

Signs and symptoms of syncope

·          Brief period of loss of consciousness

·          May be altered or awake, alert, and oriented

·          Possible seizure activity

·          Possible trauma

·          Possible abnormal vital signs (i.e. heart rate and quality)

·          Pale, cool, moist skin

·          Postural hypotension

Field management of syncope    

       BLS procedures

·          Maintain the airway

·          High flow O2 by mask

·          Left lateral if no trauma

·          Spinal immobilization if trauma is present

·          Assist with ALS procedures           

 

 

ALS procedures

·          Advanced airway prn

·          Venous access

·          Fluid challenge if clear lung sounds and signs of shock

·          Glucometer

·          Monitor

·          Valium for active seizures

·          Dextrose for hypoglycemia

·          Dopamine for hypotension if rales or if unresponsive to fluid challenge

·          Atropine for symptomatic bradycardia

·          Adenosine for SVT

·          Lidocaine for ventricular dysrhythmias

·          Cardioversion for poorly perfusing SVT or Ventricular tachycardia

 

 

Stroke

Pathophysiology

·          Injury or death of brain tissue from an interruption in blood flow.  Symptoms depend on the area of the brain affected.  Typically the motor, sensory, or speech centers are affected.

 

 

Causes of stroke

·          Hemorrhage:  rupture of a blood vessel, either intracerebral or subarachnoid.  Characteristically have a sudden onset, often preceded by a severe headache. 

·          Infarction:  occlusion of a cerebral artery by atherosclerosis or embolism

 

Field management of stroke

·        BLS procedures

·          Maintain airway

·          High flow O2 by mask

·          Left lateral position if no signs of trauma

·          Spinal Immobilization if trauma or unknown mechanism of injury

·          Assist with ALS procedures

 

·        ALS procedures

·          Advanced airway prn

·          Venous access

·          Glucometer

·          Monitor

·          Valium if actively seizing

·          Dextrose for hypoglycemia

 

 

INITIAL ASSESSMENT OF ALTERED PATIENTS

 

1).  Assess environment:  (may need to manipulate the environment)

·        Safety of rescuers and environment

  • Environmental factors
    • Patient location (home, street, convalescent, etc.)
    • Weapons (may indicate trauma mechanism)
    • Medications (may offer clues to past medical history)

o       Witnesses (may help to explain circumstances)

o       Empty pill bottles may indicate an overdose

  • Mechanism of injury
  • Number of patients

 

2).  Airway  (determine responsiveness and patency of airway)

  • Initiate spinal precautions if indicated
  • Open the airway using the chin lift/head tilt or jaw thrust maneuver
  • Remove any obstruction
  • BLS Maneuvers until open airway is achieved
  • Patient may be altered or unconscious and unable to protect or maintain their airway
 
 

 

 

 

 

 

 

 

 

 

 

 

 


3).  Breathing:  assess rate, rhythm, and tidal volume

  • If the patient is not breathing, begin rescue breathing using mouth to mouth, mouth to mask, or bag-valve-mask
  • Is the breathing labored or unlabored

·        If labored, place the patient on oxygen

  • Assess the lung sounds during the detailed examination if trauma is not present.
  • Increased respirations and tidal volume- possible metabolic process, early to mid stage shock, head trauma.
  • Decreased respirations and tidal volume- spinal or brainstem injury, stroke, late stage of shock.

 

 

4).  Circulation:    

a).   Palpate for pulse noting: rate/rhythm/quality

            b).  Character of the pulse (weak or strong) is an indicator of the                    pressure and volume within the arteries.

            c).  Heart rate- compensatory mechanism for poor perfusion,          dysrhythmias, fever, and metabolic problems.

 

 

 

5). Skin signs:  assess color, temperature and moisture

  • Pale, cool, moist skin and delayed capillary refill are due to peripheral vasoconstriction
  • If signs of poor perfusion, consider placing patient supine
 
 

 

 

 

 

 

 

6).  Assess neurological status:  assess level of consciousness                

       (Glasgow Coma Score) and neuro deficits

  • Restlessness, agitation, and lethargy may be due to hypoxia and decreased cerebral perfusion.
  • Unconsciousness and coma may be due to prolonged hypoxia, shock, head injury, metabolic disorders, neurological disorders, or other causes.