The sudden extension and spreading of a newborn's arms and legs due to a sudden jerk is called-

Raj. CHO - 2023

Pediatric Nursing

Easy

Appeared in: Raj. CHO - 2023

Explanation

The Moro reflex, or startle reflex, is an involuntary motor response that develops in utero.
It is triggered by a sudden stimulus, such as a loud noise or the sensation of falling.
The characteristic response involves three distinct components: spreading out the arms (abduction), pulling the arms in (adduction), and usually crying.
This reflex is a normal part of infant development and is routinely checked by healthcare providers after birth.
Its presence indicates a healthy and intact central nervous system.

Option A: The Babinski reflex involves the foot's response to stimulation, not the entire body's response to a jerk.
Option C: The Grasp reflex is the involuntary curling of fingers or toes around an object that touches the palm or sole.
Option D: The Gag reflex is a protective reflex to prevent choking, triggered by stimulation of the posterior pharynx. It does not involve limb movement.

Visual 1: Video - A short clip demonstrating a healthcare provider eliciting the Moro reflex in a newborn by gently allowing the head to drop back slightly. This helps visualize the two phases of the reflex: arm extension and flexion.
Visual 2: Diagram - A simple illustration comparing the Moro reflex, Babinski reflex, and Grasp reflex, showing the different stimuli and corresponding infant responses for each.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Identification of newborn primitive reflexes based on stimulus and response as background academic context rather than a clinical decision trigger.
Assessing primitive reflexes like the Moro reflex is a fundamental part of the newborn neurological examination. It provides a quick, non-invasive way to evaluate the integrity of the central nervous system.
An absent, weak, or asymmetrical Moro reflex is a significant red flag. It requires immediate further investigation to rule out conditions like birth trauma (e.g., brachial plexus injury, fractured clavicle), brain damage, or severe neurological disorders.
What if? If a newborn displays a Moro reflex on the right side but not the left, the nurse should suspect a left-sided injury, such as a fractured clavicle or damage to the brachial plexus nerves, and should immobilize the arm and report the finding to the pediatrician for imaging and consultation.

How to Approach the Question

First, read the question carefully to identify the key actions: 'sudden extension and spreading of a newborn's arms and legs' and the trigger: 'a sudden jerk'.
Next, recall the common primitive reflexes tested in newborns.
Evaluate each option against the description in the stem.
Babinski reflex is related to the foot. Eliminate this option.
Moro reflex is the 'startle' reflex, which matches the description of a response to a sudden jerk involving arm and leg extension. This is a strong candidate.
Grasp reflex involves the hands or feet closing around an object. This does not match. Eliminate this option.

Concept Tested & Keywords

Concept Tested: Identification of newborn primitive reflexes based on stimulus and response.
Stem keywords: newborn, sudden extension, spreading of arms and legs, sudden jerk
Lead-in keywords: is called
Negative lead-in flag: false

QpDEeaC1JGGC8PtRRtB967