OB EXAM 1 MATERIAL

• Adaptation to Extrauterine Life o Cardiovascular: NB must initiate respirations & sustain extrauterine oxygenation  When born, infant forced to take in oxygen thru lungs.  Shunts close & vessels clot off & regress o Respiratory: First breath also in response to temperature & pressure changes, light & noise.  1st breath requires great pressure; 40-70 cm H2O. Small amt of fluid present in lungs.  1/3 rd of this fluid forced out by pressure of vaginal birth; rest absorbed by lung tissue. C/S infants may need more suctioning & oxygen therapy. o Renal: Renal function does not fully mature until > 1st yr. 1st void occurs within 1st 24 hrs.  No urine for 36 hrs. needs further eval. for obstruction or absent kidneys.  1st voiding may be o Gastrointestinal: GI tract sterile @ birth; bacteria enters GI tract thru mouth within 24 life. Bacteria needed for prod. Vit.K  Infant: limited ability to digest fats & starches  Meconium passed 1st 24-48 hrs. of life  By 2nd - 3rd day, transitional stool passed • Thermogenesis o Brown fat : helps conserve body heat; produces heat.  Found in upper chest, back of neck, around abdomen.  Is deposited in 2nd trimester; Helps regulate body temp>delivery.  Radiant warmer - helps regulates body temp. by conserving heat.  Newborns can produce sufficient heat in optimal thermal  Environment if warm enough.  Rapid heat loss occurs in suboptimal environment [cooler].  Infants do not shiver; can go into cold stress quickly.  Uses up extra glucose & oxygen to thermoregulate.  Leads to: • metabolic acidosis; respiratory distress • Hypoglycemia; Jaundice; decreased surfactant production o Infants Lose heat in 4 ways:  Convection  Evaporation  Conduction  Radiation o IMMUNOLOGIC:  Newborn still prone to infection, handwashing important!  IgG: Infant born with passive immunity from mom. Fetus makes own starting @ 20 wks  IgM too large to cross; makes own after delivery.  IgA do not cross placenta. Produced by infant > birth @ 6-12 wks. Found in breast milk. • Care of newborn in delivery room o Adequate breathing pattern established o Mouth suctioned 1st o Nurse wraps infant in warm blanket & places under radiant warmer