Exam 2 Study Guide - Summary Maternity and Pediatric Nursing PDF

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Chapter 17, 18...

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Exam 2 Study Guide Chapter 17 Cardiovascular System Changes: KNOW REFLEXES AND WHEN THEY GO AWAY SPINA BIFIDA (2 DIMPLES?) GALLANT REFLEX SKIN TO SKIN BENEFITS DEHYDRATED BABY= SUNCK IN FONTANELS ACROCYANOSIS WHEN FEET ARE MORE BLUE THAN HANDS BABY IS COLD HEART RATE: 120-160 SLEEPING BABY: HEART RATE COULD DROP AS LOW AS 100 SKIN TAGS ARE NORMAL BUT SHOULD PROMPT FURTHER INVESIGATION BILIRUBIN: TRAUMA, BLOOD COMPENTS, CONJUGATION IGA, IGG, IGM SKIN: FIRST LINE OF DEFENSE, TEMPERATURE, PREVENTS DEHYDRATION BLACK WOMEN CAN HAVE WHITE BABIES 108 KCAL DAY OPTIMAL DIET FOR NEWBORN

-The umbilical vein carries oxygenated blood from the placenta to the fetus -The ductus venous allows for the majority of the blood to bypass the liver and merge with blood moving through the vena cava bringing it to the heart sooner. The foramen ovale allows the blood from the right atrium to move to the left atrium which bypasses the pulmonary circulation (lungs). -The ductus arterioles connects the pulmonary artery to the aorta which also skips the pulmonary circuit (lungs) -Only a small amount of blood goes to the lungs for perfusion purposes -At birth the newborn circulation and placental oxygen exchange must switch to pulmonary gas exchange (lungs) -The changes must include increased pulmonary blood flow, removal of the placenta, closure of the foramen ovale (the opening between the right and left atrium) and closure of the venous ductus and ductus arterioles -The stresses of birth release catecholamine’s that are critical for the transition into extrauterine life. - The increased levels of epi and norepi stimulate increased cardiac output and contractility; stimulate surfactant release (needed for oxygen and gas exchange) and promotion of lung fluid clearance

Fetal to neonatal Circulation Changes: -Circulation changes as soon as the fetus separates from the placenta -When the cord is clamped is when the first breath is taken and lungs begin to function -Systemic vascular resistance increases and blood return via inferior vena cava decreases -Decrease in pulmonary vascular resistance and increase in pulmonary blood flow -Foreman ovale closes with a decrease in pulmonary vascular resistance decreasing right sided heart pressures. It closes when left atrial pressure increases and right atrium pressure decreases. Normally functionally closes at birth and permantantly closes in several weeks. -The ductus arterioles and venous ductus are no longer needed and turn into ligaments over time. -With closure of the foramen ovale oxygenated blood and deoxygenated blood now become separated -During fetal life the ductus arterioles protected the lungs from circulatory overload by shunting blood right to left into the descending aorta to the rest of the body -Patency of the ductus arterioles is protected by prostaglandins E2 during fetal life -Ductus arterioles functionally close a few hours after birth and its closure depends on increased oxygenation resulting from aeration of the lungs after birth -The venous ductus closes within a few days after birth because it’s shunting of blood is no longer needed with the activation of the liver. The liver now takes over the function of the placenta -The umbilical vessels (1 vein, 2 arteries) begin to constrict and are no longer needed, also becoming ligaments (One aretery is associated with renal and GI abnormalities) Heart Rate: -During first few minutes after birth the infant’s heart rate is between 110-160 but then decreases to an average of 120-130. -The newborn is dependent on the heart rate for maintance of cardiac output and blood pressure. -BP normally plateaus a week after birth -Cardiac defects can be determined through a thorough physical assessment of the newborns cardiovascular system. The nurse should be able to identify any abnormalities because this could lead to early detection and treatment. -A transient functional cardiac murmur may be heard during the neonatal period as a result of cardiovascular changes. -Fluctuations of heart rate and blood pressure mimic baby’s behavioral state. (If baby is agitated the heart rate and blood pressure will be elevated) -Tachycardia may be found as a result of fluid volume loss, cardio respiratory disease, drug withdrawal and hyperthyroidism. -Bradycardia is found with apnea and hypoxia

Blood volume: -The amount of blood the baby has depends on the amount of blood transferred to the infant from the placenta at birth. -Late clamping (after 3 minutes) is better than early clamping (30-40 seconds). Late clamping improves the infants cardiopulmonary adaption, prevents iron deficient anemia without increasing risk of hypervolemia, increases blood pressure, improves oxygen transport, and increases red blood cell flow. -Cord blood “nature’s first stem cell transplant” Blood Components: -Fetus has more red blood cells at birth. They are larger in size and have a greater affinity for oxygen. After birth the RBC count increases and the RBC decreases in size. This is due the RBC now living in an environment where there is much more pulmonary oxygenation. -An infant’s hemoglobin initially declines as a result of a decrease in neonatal red blood cell mass -Leukocytosis (increased white blood cell count) is present after birth due to the trauma of birth. -The newborns platelet aggregation and platelet count are the same as adults -Blood test results of the newborn re dependent of where the blood is drawn from, capillary blood has higher levels of hemoglobin and hematocrit compared to venous blood, placental transfusion (early vs. late cord clamping), gestational age (increased age is associated with increased RBC and hemoglobin) NORMAL NEWBORN BLOOD VALUES Hemoglobin- 16-18 Hematocrit- 46-68% Platelets- 150,000-350,000 RBC 4.5-7.0 (1,000,000) WBC 10-30000 Respiratory System Adaptations: -Lung aeration leads to the establishment of functional residual capacity allowing for gas exchange to begin -The first breath results in the lungs filling increasing pulmonary pressure which pushes the diaphragm down -While the mom is in labor she is breathing rapidly (hypercapnia), hypoxic, and acidodic, all of these help initiate the baby to breath -Inspiration of air and expansion of lungs increase tidal volume -Surfactant prevents alveolar collapse at the end of expiration and loss of lung volume -Normal lung function depends on surfactant which permits a decrease in surface tension at the end of expiration to prevent atelectasis -The newborns chest wall is floppy due to the high cartilage content and poorly developed musculature

-The fetus lives in a fluid filled environment which means the fetus’s body is full of fluid as well. When the baby is birthed vaginally the compression help eliminate most of the fluid and the rest is removed through lymphatics and pulmonary capillaries. C- Section babies are at risk for not removing this fluid effectively and this could result in transient tachypenea and poor oxygenation. Thus needing o2 supplementation for longer. Lungs: For the newborns lungs to be functional the following events must occur ~initiation of respiratory movement ~expansion of the lungs ~establishment of functional residual capacity (ability to retain some air in lungs after expiration) ~Increased pulmonary blood flow ~Redistribution of cardiac output -Initial breathing is probably the result of environment changes (light, sound, temp) and the low oxygen concentrations of the newborns blood Respirations: -Newborn respirations are shallow, irregular, ranging from 30 to 60 rpm with short periods of apnea -RPM depends on the infant’s emotional state (stressed equals increased respiratory rate) -Signs of respiratory distress are: cyanosis, tachypnea, grunting, sternal retractions, and nasal flaring. -Respirations should not be labored and chest expansion should be equal -Periodic breathing is breathing that stops for 5-10 seconds with change in heart rate. Associated with the first few days of life -Apnea periods lasting longer than 15 seconds with cyanosis and changes in heart rate need to be further evaluated Newborn Temperature Regulation: -Babies are dependent on their environment for maintenance of body temperature, much more right after birth -One of the most important elements of the newborn is obtaining a stable body temperature -New born temperature ranges from 97.9-99.7 (36.6- 37.6) -SKIN TO SKIN, highly encouraged after birth and during painful procedures -Thermoregulation is the process of maintaining the balance of heat loss and heat production to maintain its core internal temperature. Heat Loss: -Thin skin with blood vessels close to the surface -Lack of shivering ability to produce heat until 3 months of age -Limited stores of metabolic substrates (glucose, glycogen, fat)

-Limited use of voluntary muscle activity or movement to produce heat -Large body surface area compared to weight -Lack of subQ fat -Little ability to change position (fetal position) -No ability to change clothing or get blankets -Inability to communicate that they are cold -Newborn temperature with amniotic fluid on body can drop 3-6 degrees -Heat can be lost by conduction (3%), convection (34%), evaporation (24%), and radiation (39%) Conduction: heat lost from warm baby to cold mattress, touching baby with cold hands, metal scale. Always use a cloth or blanket to cover a cold surface to prevent heat loss by conduction Convection: Heat lost related to a cold breeze that blows over baby, or air-conditioning. Keep baby out of areas with a breeze. Use blankets to cover baby Blankets, clothing, clothes are considered Isolettes Evaporation: Heat loss when a liquid turns into a vapor. Insensible (from skin, respirations), Sensible (sweating). Can happen when baby is born and covered with amniotic fluid, or bathing. Keep baby dry to prevent heat loss by evaporation Radiation: Heat loss by being close to cooler objects but not in direct contact. Laying baby by a cold window. Newborn will become cold even if wrapped in a warm isolette. Keep cribs and isolettes away from outside walls, cold windows, and air conditioners. Also babies should be transported in radiant warmers when going to procedures. Overheating: Limited isolation and limited sweating ability predisposes the baby for overheating. The primary heat regulator is located in the hypothalamus and central nervous system. The baby’s immature central nervous system makes it difficult to maintain this balance. Isolette is too warm or baby is placed by a hot window may lead to hyperthermia. Over heating increases fluid loss, respiratory rate, and metabolic rate considerably. Thermoregulation: Newborns have a decreased ability to regulate their body temperature producing heat through non-shivering themogenesis. -Thermoregulation is related to the newborns rate of metabolism and o2 consumption. The new born attempts to regulate temperature by increasing metabolic rate and increasing muscular activity through movement, increasing peripheral vasoconstriction and assuming a fetal position to hold in heat and minimize exposed body surface area. -Effects of cold stress in the newborn brown fat metabolism – The newborn first experiences an increase in norepi in response to a cold environment. This then influences the triglycerides to stimulate brown fat metabolism. Neutral Thermal Environment is an environment in which body temperature can be maintained without an increase in metabolic rate or oxygen.

Neutral Thermal Environment promotes growth and stability, conserves energy, and minimizes heat (energy) and water loss. When the environment temperature decreases the baby responds by consuming more oxygen, tachypnea and as a result the metabolic rate increase. Non-shivering Thermogenesis- Brown fat is oxidized in response to cold temperature. Brown fat is a vascular tissue only found in newborns that is able to convert chemical energy into heat when activated by the SNS. It’s produced in the 3rd trimester and disappears in 3 to 5 weeks after birth. Found between he scapulae, axillae, mediastinum (Sternum area), and areas surrounding the kidneys and adrenal glands. Baby gets cold- norepi is released- stimulates brown fat metabolism by breaking down triglycerides- increases heart rate/ cardiac output- increases blood flow through brown fat- blood becomes warmed Cold stress is excessive heat loss that requires a new born to use compensatory mechanisms (nonshiverring thermogenesis, tachypnea) to maintain core temp. Cold stress can be severely damaging to an infant. As temperature drops the new born becomes less active, lethargic, hypotonic and weaker. ALL NEWBORNS ARE AT RISK FOR COLD STRESS. Esp. within first 12 hrs of life Premies are more at risk because they have fewer fat stores that full term babies, poorer vasomotor responses and less insulation to cope with a hypothermic event. Cold stress can lead to: depleted brown fat stores, increased o2 needs, respiratory distress, increased glucose consumption leading to hypoglycemia, metabolic acidosis, jaundice, hypoxia, and decreased surfactant production.

To minimize effects of cold stress: use prewarmed blankets, keep infant transporter/ warmer charged at all times, dry the new born completely, skin to skin, promote early breast feeding to provide fuel for nonshiverring thermogenesis, heated humidified o2, radiant warmers, defer bathing until newborn is stable, avoid temp probe placing in area of brown fat. Hepatic System Functions: Liver is involved in metabolism of carbs, proteins, lipids, trace elements, and vitamins. At birth the liver assumes the role of the placenta. Most enzymatic pathways are present at birth but t don t function until around 3 months of age. Blood coagulation (which is why we give vit K post birth), iron storage (full term babies get a lot of iron from mom before birth), Carb metabolism, conjugation of bilirubin. Glycogen reserves provide energy and may become depleted due to respiratory or cold stress. Iron storage: As red blood cells are damaged during birth their iron is released and stored in the liver until new RBC need to be produced. Newborn iron stores are determined by body hemoglobin content and length of gestation.

If mom had a good amount of iron during the pregnancy then the infant should have iron stores that could last up to 6 months. Carb Metabolism: Glucose is important for brain metabolism Newborns are no longer able to use the maternal glucose supply. They must learnt o regulate their blood glucose and adjust to an intermittent feeding schedule. Hypoglycemia is one of the most frequent problems encountered in a newborn and maintaining glucose homeostasis is an important physiologic event during the fetal to new born transition. Glucose is the major source of energy for a newborn after birth. The liver releases glucose from it glycogen stores for the first 24 hours. Encourage early breast or bottle feeding is an important intervention to help stabilize the infant’s glucose levels. Bilirubin Conjugation: In utero the placenta took care of eliminating excess bilirubin in the blood. Bilirubin circulates in plasma and is taken up by the liver cells which are then changed into water soluble pigment excreted in the bile. This conjugated form of bilirubin is excreted from liver cells as a constituent of bile.* The source of billirubin in the newborn is the destruction of erythrocytes RBC’s. This is normal after birth because fewer RBC are needed to maintain extrauterine life. -The RBC die (approx 80 days) the heme in their hemoglobin is converted to bilirubin. Billirubin is released in an unconjugated form called indirect billirubin which is fat soluble Enzymes, proteins, and different cells in the reticularendothelial system and liver process the uncongujated bilirubin into conjugated bilirubin or direct bilirubin. Direct bilirubin in water soluble and enters the GI tract via bile and is eventually excreted through feces. The kidneys also excrete some of the billirubin as well. Newborns produce bilirubin at approx 6-8 mg/kg/day (almost twice the production of adults) Billirubin production normally declines to adult levels by 10-14 days after birth The Newborn liver is immature and cannot conjugate bilirubin as quickly as needed. Jaundice is the result of the livers inability to break down and excrete bilirubin in the blood stream Billirubin is toxic and needs to be excreted Blood test to determine billirubin levels are test that measure bilirubin in the serum Total Bilirubin: Combination of Conjugated and Uncongugated bilirubin. Unconjugated bilirubin that deposits itself in the mucous membranes gives the infant a yellow appearance called jaundice also known as Icterus

Jaundice occurs in more than 50% of all newborns Elevated levels of billirubin can cause billirubin encephalothopy a form of devastating permanent rain damage. Risk factors include: Fetal-maternal blood group incompatibility, prematurity, asphyxia at birth, insufficient intake of milk during breast feeding, drugs diazepam, oxytocin, sulfa drugs or erythromycin, chloramphenicol, maternal gestational diabetes, infrequent feedings, male gender, trauma during birth resulting in cephalhematoma, cutaneous bruising from birth trauma, polycytothemia, genetics, TORCH (toxoplasmosis, other viruses, rubella, cytomegavirus, herpes), ethnicity (native American or Asian) Causes can be classified into 3 groups: Bilirubin overproduction, Decreased bilirubin conjugation, impaired bilirubin excretion. Gastrointestinal System Adaptations: Full term baby has the capacity to swallow, digest, metabolize, and absorb food taken in soon after birth. The Ph of the infant’s stomach mimics the amniotic fluid (mildly acidic) The sterile gut changes rapidly depending on what the diet of the child is (breast, bottle) Bowel sounds are heard after birth but may be hypoactive during the first day Mucosal Barrier: Babies go from a sterile environment to instant colonization of microorganisms Colonizatation of the gut is dependent on what the child eats Colonization occurs in the first 24 hours and is important for the production of Vit K After birth baby will be colonized by mom’s flora Human breast milk provides a passive mechanism to protect the newborn against the dangers of deficient intestinal defense system. It contains antibodies viable leukocytes, and many other substances that can interfere with bacterial colonization and prevent harmful penetration. Stomach and digestion: The physiologic capacity of the newborn stomach is less than it anatomical capacity. After the first 4 days they level out. First 24 hours the infant’s stomach will not stretch, it takes 1-2 days For bottle fed infants small frequent feedings tend to set up a healthy eating pattern from the start Breast fed babies self regulate how much they consume Small frequent meals are best. Coaxing the baby to eat more results in overfeeding. May lead to obesity later in life The cardiac sphincter, pharnoesophageal, and nervous control of the stomach are immature and uncoordinated peristalsis leads to frequent regurgitation. Burping may minimize regurgitation

Newborns can digest simple carbs and protein. However they limited ability to digest complex carbs and fats because amylase and lipase are low at birth. Newborns excrete fair amounts of lipids resulting in fatty stools Newborns lose 5-10% body weight in first week. Water shifts from intracellular spaces to extracellular space and have insensible water loss To gain weight a term new born must eat 108 kcal/kg/day to 6 months of age. Bowel Elimination: Meconium is the first stool passed, composed of amniotic fluid, shed mucosal cells, intestinal secretions, and blood. IT is greenish black and passed 12 to 24 hours after birth. First meconium is semi sterile which changes rapidly with ingestion of bacterium After feedings a transitional stool develops (greenish yellow to yellowish brown thinner in consistency) and then to the milk stool Breastfed- light mustard/gold, seedy, stringy to pasty consistency, sour smelling Bottle fed- tan-yellow/ yellow green color, loose, pasty, sometimes firmer (depends on the formula) Newborns that are fed early pass stools sooner, helps reduce bilirubin build up Renal system changes: A full complement of one million nephrons ...