An adult has just been brought in by ambulance after a motor vehicle accident. When assessing the client, the nurse would expect which of the following manifestation could have resulted from sympathetic nervous system stimulation?

1. A

   A rapid pulse and increased respiratory rate

2. B

   Decreased physiological functioning

3. C

   Rigid posture and altered focus

4. D

   Increased awareness and attention

Appeared in: OSSSC Nursing Officer-2023

Explanation

• In response to acute trauma, the sympathetic nervous system (SNS) initiates the 'fight or flight' response.
• This response involves the release of catecholamines like epinephrine and norepinephrine.
• These hormones act on the heart to increase its rate (tachycardia) and on the lungs to increase the respiratory rate (tachypnea).
• The primary goal of these changes is to enhance oxygen delivery to vital organs and muscles, preparing the body for immediate action or to cope with injury.

Why Other Options Were Wrong

• Option B: This is the opposite of the SNS response. The SNS increases physiological functioning to prepare for 'fight or flight'.
• Option C: While muscle tension can cause a rigid posture, and focus can be altered, these are not the primary, life-sustaining physiological responses that a nurse prioritizes in an initial trauma assessment.
• Option D: Although increased awareness is an effect of SNS stimulation (e.g., pupil dilation, heightened senses), the most critical and measurable manifestations for a nurse to assess in a trauma patient are the vital sign changes related to circulation and breathing.

Related Visual

Clinical Relevance

• Nursing practice connection: Safe nursing care depends on performing Sympathetic Nervous System (SNS) Response in Trauma in the correct sequence, documenting the action clearly, and monitoring for the expected response.
• In any trauma or emergency setting, a nurse's first action is to assess Airway, Breathing, and Circulation (ABCs). A rapid pulse and increased respiratory rate are direct measures of B and C, indicating the body is under significant stress and trying to compensate.
• Monitoring these vital signs over time is crucial. A persistently high heart rate can indicate ongoing blood loss or shock, while a sudden drop could signal decompensation.
• What if? If the patient in the MVA presented with a slow pulse (bradycardia) and low blood pressure, the nurse should suspect a different type of shock, such as neurogenic shock (often from spinal cord injury), which involves a loss of sympathetic tone, rather than the expected hypovolemic or cardiogenic shock with a classic SNS response.

How to Approach the Question

• First, identify the key elements in the question: 'motor vehicle accident' implies acute trauma and stress, and 'sympathetic nervous system stimulation' is the specific physiological process.
• Recall the function of the sympathetic nervous system (SNS). The mnemonic 'fight or flight' is useful. Think about what your body does when it's scared or stressed.
• Evaluate each option based on the 'fight or flight' model:
• Does your heart beat faster? Yes. Do you breathe faster? Yes. This makes option A a strong candidate.
• Does your body slow down? No, it speeds up. This eliminates option B.
• While you might tense up (rigid posture), are the changes to your heart and lungs more fundamental to survival? Yes. This makes option A a better answer than C.

Concept Tested & Keywords

• Concept Tested: Sympathetic Nervous System (SNS) Response in Trauma
• Stem keywords: motor vehicle accident, sympathetic nervous system stimulation, assessment, manifestation
• Lead-in keywords: expect
• Clinical cues: The context of a 'motor vehicle accident' signals an acute, high-stress trauma event, which is a classic trigger for the 'fight or flight' response.

Question ID

QK3D8WU9PBaAM7mZEqqh56

Copy ID

Reference Book

E6 Nursing Fundamentals Taylor p. 1032-1034

E6 Physiology Guyton 4SAE Part 2A p. 17-19

E6 Nursing Brunner Adult Health 3SA Vol 2 Part 2 p. 89-91