Chapter 45- Sensory Functioning

Senses Involved in Sensory Reception:

1. Visual (Vision): Perception of light and objects.
2. Auditory (Hearing): Perception of sound.
3. Olfactory (Smell): Detection of odors.
4. Gustatory (Taste): Recognition of taste sensations.
5. Tactile (Touch): Detection of pressure, temperature, pain, and texture.
6. Stereognosis: The ability to recognize the form and solidity of objects by touch.
7. Kinesthetic and Visceral Senses: Relate to movement and internal body functions (e.g., sense of body position and internal sensations such as hunger or pain).
8. Proprioception: Awareness of body position and movement without visual cues.

Four Conditions to Receive Sensory Data:

1. Stimulus: A trigger that activates sensory receptors.
2. Receptor: A sensory cell or nerve ending that responds to stimuli.
3. Nervous Pathway to the Brain: The transmission of sensory information from receptors to the brain.
4. Functioning Brain: The brain processes and translates sensory input into meaningful perceptions.

Reticular Activating System (RAS):

• Function: Mediates arousal by monitoring and regulating incoming sensory stimuli, either enhancing or inhibiting cortical arousal.
• Optimal State: Sensoristasis, the state of optimal arousal where sensory input is balanced.
• Components: Extends from the hypothalamus to the medulla, responsible for maintaining consciousness and alertness.

States of Awareness:

• Conscious States: Include delirium, dementia, confusion, normal consciousness, somnolence, minimally conscious states, and locked-in syndrome.
• Unconscious States: Include sleep, stupor, coma, and vegetative states.

Sensory Alterations:

1. Sensory Overload: The brain is overwhelmed by excessive sensory stimuli, leading to an inability to process or ignore them.
   • Symptoms: Anxiety, confusion, difficulty focusing.
   • Nursing Care: Focus on reducing excessive stimuli and helping the patient regain control over their environment.
2. Sensory Deprivation: Occurs when there is reduced sensory input or the inability to perceive stimuli. Patients at risk include those in monotonous environments or those with impaired sensory reception.
   • Effects:
     • Perceptual disturbances (hallucinations, altered time perception).
     • Cognitive disturbances (decreased problem-solving, confusion).
     • Emotional disturbances (depression, anxiety).
3. Sensory Deficits: Impaired function of one or more senses (e.g., vision or hearing loss).
4. Sensory Poverty: Lack of meaningful sensory input in a modern environment.

Factors Affecting Sensory Function:

1. Developmental considerations: Age-related changes impact sensory function (e.g., presbyopia, presbycusis).
2. Culture: Cultural norms influence the perception and expression of sensory stimuli.
3. Personality and lifestyle: Personal preferences and habits affect sensory perception.
4. Stress and illness: Stress and illness can alter sensory perception (e.g., numbness in neuropathy).
5. Medications: Certain drugs can impair or enhance sensory function (e.g., ototoxic drugs that damage hearing).

Nursing Process for Sensory Functioning

1. Assessment:

• History: Ask about any sensory changes, such as trouble seeing, hearing, or feeling.
• Physical Exam: Assess the function of the five senses and proprioception.
• Signs of Sensory Deprivation: Include boredom, disorientation, and hallucinations.
• Signs of Sensory Overload: Include restlessness, anxiety, and confusion.

2. Nursing Diagnoses:

• Impaired Sensory Perception: Related to vision, hearing, or other sensory functions.
• Risk for Injury: Due to diminished sensory perception.
• Sensory Overload: Caused by excessive stimuli.

3. Planning:

• Goal: Help the patient live in a safe and stimulating environment while managing sensory deficits. Encourage independence and prevent injury.

4. Interventions:

• Environmental Control: Reduce unnecessary noise and light. Ensure proper lighting for patients with vision problems.
• Communication: Use visual aids or written communication for hearing-impaired patients.
• Safety Measures: Ensure clear pathways and remove tripping hazards for those with sensory impairments.

5. Evaluation:

• Evaluate the effectiveness of interventions by assessing the patient's ability to perform daily activities and their comfort level with sensory challenges.

Improving Sensory Functioning:

• For Visually Impaired Patients:
  • Announce your presence before entering the room.
  • Keep pathways clear and offer assistance with mobility.
  • Describe the environment and sounds.
• For Hearing Impaired Patients:
  • Orient the patient before speaking.
  • Face the patient with proper lighting for lip reading.
  • Reduce background noise and check hearing aids.
• For Patients with Sensory Deprivation:
  • Provide stimuli such as social interaction, music, or tactile objects (e.g., a soft blanket).
• For Patients with Sensory Overload:
  • Reduce environmental stimuli and encourage relaxation techniques.

Communicating with Patients:

1. Confused Patients:

• Maintain frequent face-to-face contact.
• Speak calmly, simply, and directly.
• Reorient the patient to time, place, and person as needed.
• Emphasize strengths and reinforce reality when needed.

2. Unconscious Patients:

• Always assume the patient can hear you.
• Speak in a normal tone of voice.
• Minimize environmental noise and provide calm, reassuring care.

Sensory Health Maintenance:

• Health Screenings: Encourage regular vision and hearing tests, especially in older adults.
• Diet: Ensure adequate intake of vitamins that support sensory health (e.g., vitamin A for vision).
• Injury Prevention: For patients with tactile deficits, ensure they are aware of potential hazards like sharp or hot objects.