Chapter 24

2. Chapter 24 Physiologic Adaptations of the Newborn

3. Transition to Extrauterine Life • First period of reactivity • Lasts up to 30 minutes after birth • Newborn’s heart rate increases to 160 to 180 beats/min • Decreases after 30 minutes • Decrease in motor activity after period

4. Transition to Extrauterine Life—cont’d • Second period of reactivity • Occurs 4 to 8 hours after birth • Tachycardia, tachypnea occur • Meconium passed • Increased muscle tone, changes in skin color, and mucous production

5. Physiologic Adaptations • Respiratory system • Initiation of breathing • Signs of respiratory distress • Maintaining adequate oxygen supply • Cardiovascular system • Heart rate and sounds • Blood pressure • Blood volume

6. Physiologic Adaptations—cont’d • Hematopoietic system • Red blood cells and hemoglobin • Leukocytes • Platelets • Blood groups

7. Physiologic Adaptations—cont’d • Gastrointestinal system • Digestion • Stools • Meconium • Feeding behaviors

8. Physiologic Adaptations—cont’d • Hepatic system • Iron storage • Carbohydrate metabolism • Jaundice • Coagulation • Immune system

9. Physiologic Adaptations—cont’d • Integumentary system • Caput succedaneum • Cephalhematoma • Subgaleal hematoma • Sweat glands • Desquamation • Mongolian spots • Nevi • Erythema toxicum

10. Physiologic Adaptations—cont’d • Skeletal system • At birth more cartilage then ossified bone • Neuromuscular system • Newborn reflexes • Neurologic assessment

11. Physical Assessment • General appearance • Vital signs • Baseline measurements of physical growth • Weight and length • Head circumference • Neurologic assessment

12. Behavioral Characteristics • Sleep-wake states • Other factors influencing behavior of newborns • Gestational age • Time • Stimuli • Medication

13. Behavioral Characteristics—cont’d • Sensory behaviors • Vision • Hearing • Smell • Taste • Touch

14. Behavioral Characteristics—cont’d • Response to environmental stimuli • Temperament • Habituation • Consolability • Cuddliness • Irritability • Crying

15. Key Points • Term infant’s various anatomic and physiologic systems have reached development and function that permits physical existence apart from mother • Infant has sensory capabilities that indicate state of readiness for social interaction • Appearance of jaundice during first day or persistence of jaundice for more than 7 days indicates a pathologic process

16. Key Points—cont’d • Heat loss in newborn may exceed capacity to produce heat and lead to metabolic and respiratory complications that threaten newborn’s well-being • Assessment of newborn requires data from the prenatal, intrapartal, and postpartal periods • Assessment proceeds systematically so each system is thoroughly evaluated

17. Key Points—cont’d • Some reflex behaviors are important for newborn’s survival • Personalities and behavioral characteristics of infants play major role in the ultimate relationship between infants and parents • Each full-term newborn has predisposed capacity to handle multitude of stimuli in external world