Midwife board exam- Newborn Questions and Answers 100% Pass

Midwife board exam- Newborn Questions and Answers 100% Pass Factors that initiate respiration - Biochemical- relative hypoxia at the end of labor Physical stimuli- cold, gravity, pain, light noise Rocoil from pressure on thorax while passing through vagina Sustained respiration depends on coordinated response of the following - CNS resp center Aortic and carotid chemoreceptors Thoracic mechanoreceptors Diaphragm and respiratory muscles Initial breathing serves the following purposes - Assits in conversion of fetal to extrauterine circulation clears lungs of fluids establish lung volume and expand alveoli Characteristics of normal newborn respiration - 30-60 breath per min irregular and fluctuating pattern diaphragmatic and abdominal breathing obligate nose breathing absence of nasal flaring, grunting and retractions Page 2/37 ©EmilyCharlene 2024. All Rights Reserved. When does change to from fetal to extrauterine circulation occur? - from clamming the umbilical cord throughout first weeks of life. Characterisstic of fetal circulation - low-pressure system, including placenta (low resistance circuit) Minimal circulation to lungs; bypassed via foramen oval and ductus ateriousus foramen ovale favors circulation of most oxygen rich blood to the brain Transition from Fetal to neonatal circulation - Increases systematic resistance d/t. loss of placental circuit increased pressure in LEFT ATRIUM causes functional closure of the foramen ovale Intail respiration opens pulmonary vasculature, favoring circulation to the lungs increased oxygenation of ciculating blood causes construction and functional closure of the ductus arteriosus Absence of placental circulation closes ductus venous mechanisms of neonatal heat loss - convection conduction evaporation radiation Page 3/37 ©EmilyCharlene 2024. All Rights Reserved. 3 ways a neonate creates heat - shivering (inefficient) Muscle activity (limited benefit) Thermogenesis by metabolism of brown adipose tissue 1) BAT stores are decreased in PTM and IUGR infants 2) hypoglycemia reduces efficiency of BAT metabolism Consequences of cold stress - Increased oxygen consumption, leading to relative hypoxia and acidosis metabolism of BAT and release of fatty acids decreases pH increased use of glucose, depletion of glycogen stores and hypoglycemia Worsening hypoglycemia and acidosis may result in respiratory distress Cold stress management - skin to skin with mothers chest with blanket over both prewarm blankets and resuscitation area dry newborn immediately and replace wet blankets regulate room temp and minimize exposure to air convection postpone newborn bath for at least 2 hours keep newborn warm and wrapped Glycogen stores - predominately in the liver accumulated in third trimester Risk factors for neonatal hypoglycemia - infants of DM mothers SGA or LGA Preterm or Postterm Page 4/37 ©EmilyCharlene 2024. All Rights Reserved. Intrapartum -perinatal acidemia, beta-agonit tocolysis, IV glucose administration Maternal substance abuse Glucose regulation in the healthy neonate - Normal physiologic decrease in blood glucoses appears to be essential to stimulate physiologic processes promoting glucose production 1) lowest at 1-1.5 - 5 hours after birth 2) stabilizes 3-4 hours after birth 3) IF SYMPTOMATIC and 40 mg/dL, IV glucoses is recommended 4) if there are NO symptoms, ideally infant should feed within one hour of birth and glucose should be screened 30 min after feeding by 4-24 hours blood glucose levels should remain over 45 mg/dL Indications for IV dextrose - Symptomatic infants 40 mg/ dL or those with serum glucose less than 25 mg/dL regardless of symptoms Asymptomatic infants with persistent serum glucose below 45 mg/dL Mean glucose levels from 4-72 hours - 60-70 mg/dL Sources and mechanisms of glucose maintenance - Intake of human milk or formula glycogenolysis (use of glycogen stores0 Gluconeogensis (Production of glucose from free fatty acids), glycerol and amino acids S/S of hypoglycemia - Weak cry, jitteriness, cyanosis, apnea, lethargy, poor feeding Hemoglobin F - predominant hemoglobin present at birth High affinity of O2 Page 5/37 ©EmilyCharlene 2024. All Rights Reserved. Gradually eliminated in 1st month of life Cord clamping - Evidence for infant (particularly in PTM) with delayed clamping (till pulsation stops, mean of approximately 2 min) vs immediate cord clamping neutral position on maternal abdomen is preferable below introits - theoretically can cause placental transfusion and polycythemia Normal Newborn Hbg level - 13.7-20 g/dL mean at 2 months is 12.0 Normal Newborn hematocrit - 43-63% Normal Newborn RBC count - 4.2-5.8 million /mm