Nursing 209

N209: Reproductive Health Study Guide • Difficulty with fat digestion due to lack of amylase at birth and during the first few months • Decreased production of lipase and bile acids also limits fat absorption (lipase gradually increases during first few weeks of life) • Breast milk contains lactose and is easily digested • Intestinal peristalsis: Can be influenced by anoxia in utero and can trigger meconium release into amniotic fluid • Immediately after delivery air enters the stomach and reaches the small intestine by 12 hours of age • Bowel sounds are present within 15-30 minutes due to air entry into stomach • Salivary glands are immature at birth; decreased saliva for first three months • Cardiac sphincter (between stomach and esophagus) is immature, making regurgitation common • First meconium passage usually occurs between 8-24 hours; if no meconium is passed by 72 hours, an obstruction should be ruled out • Meconium makeup: Amniotic fluid particles (vernix, skin, hair, and intestinal tract cells) • Transitions from meconium to a thick, greenish-brown to yellow and thinner stool; depends upon breast vs. bottle fed Nephrons are fully functional by 34-36 weeks • Kidneys are not fully functional until after birth • Decreased GFR; unable to remove fluid rapidly with tendency to reabsorb excess sodium • As kidneys mature and enlarge, the GFR increases; reaches adult GFR by age two • Difficulty with urine concentration due to short and narrow kidney tubules; specific gravity is usually 1.002-1.010 o May also cause loss of amino acids and glucose • Majority of newborns will void within 12 hours • If no void by 24 hours, hypovolemia is suspected; also consider obstruction • Urine may contain urate crystals due to inability to remove protein and glucose, and may appear pink-red in color • Require 60-80 ml/kg of fluids first 24-48 hours; after the first few days of life, fluid requirements increase to 100-150 ml/kg

5.14 Urinary Adaptation •

Immature immune system at birth; susceptible to infections

5.15 Immunological Adaptation •

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