The nurse explains to the parents of a 2-day-old newborn that decreased life span of neonatal red blood cells has contributed to which complication?

Choice A reason:

The tonic neck reflex, also called the fencing posture, occurs when a baby's head is turned to one side. The arm and leg on that side stretch out, while the opposite arm and leg bend up at the elbow. This reflex lasts until the baby is about 5 to 7 months old. This reflex matches the description of the question.

Choice B reason:

The Moro reflex, also called the startle reflex, is the baby's reaction to being startled. The cause is often a loud sound, a sudden movement, or even their own cry. As an adult, you may jump or gasp when you are startled. A baby will throw back their head, extend their arms and legs, cry, then pull their arms and legs back in. This reflex does not match the description of the question.

Choice C reason:

The startled reflex is not a distinct reflex in newborns. It is another name for the Moro reflex, which is explained.

Choice A reason:

Basal metabolic rate reduction. This is incorrect because a newborn under a radiant heat warmer will have an increased basal metabolic rate, not a reduced one. The basal metabolic rate is the amount of energy the body uses at rest, and it is influenced by temperature. A warmer environment will stimulate the newborn's metabolism and increase the energy expenditure. • Choice B reason:

Brown fat production. This is incorrect because a newborn under a radiant heat warmer will have less need for brown fat production, not more. Brown fat is a type of fat tissue that generates heat by burning calories. It is found in newborns and helps them maintain their body temperature in cold environments. A warmer environment will reduce the need for brown fat activation. • Choice C reason:

Shivering. This is incorrect because a newborn under a radiant heat warmer will not shiver, but shivering is not the main mechanism of heat production in newborns. Shivering is an involuntary contraction of muscles that generates heat by increasing metabolism. Newborns have limited ability to shiver because of their immature nervous system and low muscle mass. They rely more on brown fat and increased metabolic rate to produce heat. • Choice D reason:

Cold stress. This is correct because a newborn under a radiant heat warmer will prevent cold stress, which is a condition where the newborn's body temperature drops below normal and causes adverse effects. Cold stress can impair oxygen delivery, increase acidosis, decrease blood glucose, and increase the risk of infection and bleeding. A radiant heat warmer provides a neutral thermal environment for the newborn and prevents heat loss by radiation.

: 1 : 2 : 3 : 4.