Developed by D. Ann Currie, RN, MSN

Physiological Responses of the Newborn to Birth Respiratory Adaptations: Mechanical changes Chemical changes Thermal changes Sensory changes

Fetal and Neonatal Circulation

Normal Term Newborn Cord Blood

Neutral Thermal Environmental Temperatures

Physiologic Adaptations to Extrauterine Life

Newborn Urinalysis Values

Cardiovascular Adaptations Decreased pulmonary vascular resistance and increased blood flow Increased systemic pressure and closure of ductus venosus Increased left atrium and decreased right atrium pressure Closure of foramen ovale Reversal of blood flow through ductus arteriosus and increased PO2 Closure of ductus arteriosus

Transitional circulation: conversion from fetal to neonatal circulation.

Fetal-neonatal circulation. A, Pattern of blood flow and oxygenation in fetal circulation. B, Pattern of blood flow and oxygenation in transitional circulation of the newborn. C, Pattern of blood flow and oxygenation in neonatal circulation.

Fetal Laboratory Value Changes Decreased erythropoietin production Rise of hemoglobin concentration Physiologic anemia of infancy Leukocytosis Decreased percentage of neutrophils

Thermogenesis in the Newborn Large body surface area compared to mass Types of heat loss Convection Radiation Evaporation Conduction

Convection

Radiation

Evaporation

Conduction

Types of Bilirubin Unconjugated bilirubin Conjugated bilirubin Total bilirubin

Conjugation and Excretion of Bilirubin Bilirubin is transported in blood via albumin Bilirubin is transferred into the hepatocytes Attachment of unconjugated bilirubin to glucuronic acid Excreted into bile ducts, then into the common duct and duodenum Bacteria transform it into urobilinogen and stercobilinogen Bilirubin is excreted in urine and stool

Jaundice

Physiologic Jaundice Accelerated destruction of fetal RBCs Increased amounts of bilirubin delivered to liver Inadequate hepatic circulation Impaired conjugation of bilirubin Defective uptake of bilirubin from the plasma Defective conjugation of the bilirubin

Physiologic Jaundice (continued) Increased bilirubin reabsorption Defect in bilirubin excretion Increased reabsorption of bilirubin from the intestine

Liver Adaptations Iron content stored in liver Low carbohydrate reserves Main source of energy is glucose Liver begins to conjugate bilirubin Lack of intestinal flora results in low levels of vitamin K

GI Adaptations Sufficient enzymes except for amylase Digests and absorbs fats less efficiently Salivary glands are immature Stomach has capacity of mL Cardiac sphincter is immature

Fluid and Electrolyte Balance Less able to concentrate urine Limited tubular reabsorption of water Limited excretion of solutes Limited dilutional capabilities

Immunologic Responses in the Newborn IgG – passive acquired immunity via placenta IgM – usually not passively transferred Elevated levels may indicate fetal antigenic activity in utero IgA – passive acquired immunity via colostrum

Periods of Reactivity First period of reactivity Sleep phase Second period of reactivity

Mother and baby gaze at each other. This quiet alert state is the optimal state for interaction

Behavioral and Sensory Capabilities Habituation Orientation Auditory Olfactory Tasting and Sucking Tactile

End of Part 1