WEEK 9 Flashcards
Vital statistics measured in a newborn are
weight, length, and head and chest circumference
Weight
mature female newborn in the United States is
3.4 kg (7.5 lb);
for a white, mature male newborn, it is
3.5 kg (7.7 lb).
Head Circumference
34 to 35 cm (13.5 to 14 in).
Chest Circumference
2 cm (0.75 to 1 in)
Temperature
99° F (37.2° C)
Pulse
120 to 160 beats per minute (bpm).
Respiration
80 breaths per minute.
30 to 60 breaths per minute
Blood Pressure
approximately 80/46 mm Hg at birth
serves the same purpose as it does in an adult—to protect the eye from any object coming near it by rapid eyelid closure. It may be elicited by shining a strong light such as a flashlight or an otoscope light on an eye.
A sudden movement toward the eye sometimes can elicit it
Blink Reflex
If the cheek is brushed or stroked near the corner of the mouth, a newborn infant will turn the head in that direction.
This reflex serves to help a newborn find food: when a mother holds the child and allows her breast to brush the newborn’s cheek, the reflex makes the baby turn toward the breast.
The reflex disappears at about the sixth week of life. At about this time, newborn eyes focus steadily, so food source can be seen, and the reflex is no longer needed.
Rooting Reflex
When a newborn’s lips are touched, the baby makes a sucking motion.
The reflex helps a newborn find food: when the newborn’s lips touch the mother’s breast or a bottle, the baby sucks and so takes in food.
begins to diminish at about 6 months of age.
It disappears immediately flex disappears at about the sixth week of life.
Sucking Reflex
same as in the adult.
Food that reaches the posterior portion of the tongue is automatically swallowed.
Gag, cough, and sneeze reflexes also are present in newborns to maintain a clear airway in the event that normal swallowing does not keep the pharynx free of obstructing mucus.
Swallowing Reflex
A newborn extrudes any substance that is placed on the anterior portion of the tongue. This protective reflex prevents the swallowing of inedible substances. It disappears at about 4 months of age. Until then, the infant may seem to be spitting out or refusing solid food placed in the mouth.
Extrusion Reflex
Newborns grasp an object placed in their palm by closing their fingers on it. Mature newborns grasp so strongly that they can be raised from a supine position and suspended momentarily from an examiner’s fingers. This reflex disappears at about 6 weeks to 3 months of age. A baby begins to grasp meaningfully at about 3 months of age.
Palmar Grasp Reflex
Newborns who are held in a vertical position with their feet touching a hard surface will take a few quick, alternating steps. This reflex disappears by 3 months of age. By 4 months, babies can bear a good portion of their weight unhindered by this reflex
Step (Walk)-in-Place Reflex.
When an object touches the sole of a newborn’s foot at the base of the toes, the toes grasp in the same manner as do the fingers. This reflex disappears at about 8 to 9 months of age in preparation for walking. However, it may be present during sleep for a longer period.
Plantar Grasp Reflex
When newborns lie on their backs, their heads usually turn to one side or the other.
The arm and the leg on the side toward which the head turns extend, and the opposite arm and leg contract.
If you turn a newborn’s head to the opposite side, he or she will often change the extension and contraction of legs and arms accordingly.
This is also called a boxer or fencing reflex, because the position simulates that of someone preparing to box or fence. It may signify handedness.
The reflex disappears between the second and third months of life.
Tonic Neck Reflex
initiated by startling a newborn with a loud noise or by jarring the bassinet.
The most accurate method of eliciting the reflex is to hold newborns in a supine position and allow their heads to drop backward about 1 inch.
In response to this sudden head movement, they abduct and extend their arms and legs.
Their fingers assume a typical “C” position.
It is strong for the first 8 weeks of life and then fades by the end of the fourth or fifth month, at the same time an infant can roll away from danger.
Moro Reflex
When the sole of the foot is stroked in an inverted “J” curve from the heel upward, a newborn fans the toes (positive Babinski sign)
. This is in contrast to the adult, who flexes the toes. This reaction occurs because nervous system development is immature.
It remains positive (toes fan) until at least 3 months of age, when it is supplanted by the downturning or adult flexion response.
Babinski Reflex
If pressure is applied to the soles of the feet of a newborn lying in a supine position, he or she pushes back against the pressure.
This and the two following reflexes are tests of spinal cord integrity.
Magnet Reflex
If one leg of a newborn lying supine is extended and the sole of that foot is irritated by being rubbed with a sharp object, such as a thumbnail, the infant raises the other leg and extends it, as if trying to push away the hand irritating the first leg.
Crossed Extension Reflex
When newborns lie in a prone position and are touched along the paravertebral area by a probing finger, they flex their trunk and swing their pelvis toward the touch.
Trunk Incurvation Reflex
A newborn who is held in a prone position with a hand underneath, supporting the trunk, should demonstrate some muscle tone.
Babies may not be able to lift their head or arch their back in this position (as they will at 3 months of age), but neither should they sag into an inverted “U” position.
The latter response indicates extremely poor muscle tone, the cause of which should be investigated.
Landau Reflex
leads to jaundice, or yellowing of the skin
This occurs on the second or third day of life in about 50% of all newborns, as a result of a breakdown of fetal red blood cells (physiologic jaundice).
The infant’s skin and the sclera of the eyes appear noticeably yellow.
This happens because the high red blood cell count built up in utero is destroyed, and heme and globin are released.
Hyperbilirubinemia
