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Neonatal Physiology
Tulane Pediatric Surgery
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Topics
Fluids and Electrolytes
Cardiopulmonary
Temperature Regulation
Jaundice
Host Defenses
Surgical Stress Response
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Fluids and Electrolytes
Glucose
Placental
Glycogen Storage
Gluconeogenesis
Hypoglycemia
SGA
Surgical Pts
Hyperglycemia
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Fluids and Electrolytes
Calcium
Placental Diffusion
75% third trimester
Limited Stores
Renal Immaturity
Hypoparathyroidism
Citrate can bind and decrease Ca
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Fluids and Electrolytes
Magnesium
Associated with Calcium
Growth Retardation
Maternal Diabetes
Exchange Transfusions
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Fluids and Electrolytes
Blood Volume
Highest Delivery
Cord Clamping
Polycythemia
Hct>65
Diabetes
Toxemia SGA
Partial Exchange
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Fluids and Electrolytes
Hemolytic Anemia
Maternal Antibodies
Direct Coombs Rh most common
Congenital Infections
SS Dz
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Fluids and Electrolytes
Anemia
Premature Infants
Erythropoeitin
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Fluids and Electrolytes
Hemoglobin
80% Fetal
Erythropoeisis 2-3 months P50 Adult Hgb 27 mmHg
P50 Fetal Hgb 8 mmHg
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Jaundice
Hemolysis
Glucoronyl Transferase
Unconjugated Hyperbilirubinemia
Peaks 3rdDay 6-7mg/dl
Resolves Day 10
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Jaundice
Non Physiologic
Breast Feeding
Hemolytic Disease
Hypothyroid
Pyloric Stenosis
Crigler-Najar
Extravascular Blood
Biliary Atresia
Hepatitis
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Jaundice
Non-Physiologic
Conjugated > 2mg/dl
Rises > 5mg/dl/day
Born Jaundiced
Doesnt Resolve
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Temperature Regulation
Evaporation
Conduction
Convection
Radiation
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Temperature Regulation
Humidified Environments
Incubator
Ventilator Circuits
Radiant Warmers
Dry Heat
Increased insensible losses
Clothes/Blankets
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Temperature Regulation
Hypothermia
Hypoglycemia
Vasoconstriction
Coagulopathy
Emergence from Anesthesia
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Renal Function
Low GFR
Better at 2 weeks
Normal at 1-2 years
Decreased Concentrating Ability
600mOsm
Insensitive to ADH
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Cardiopulmonary
Fetal Circulation
Right to Left Shunts
Foramen Ovale
Ductus Arteriosus
Hypoxemia
Hypercarbia
Acidosis
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Cardiopulmonary
Persistent Fetal Circulation
Sepsis
Meconium Aspiration
Congenital Diaphragmatic Hernia
Idiopathic
Treatment
Ventilation Pharmacology
ECMO
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Cardiopulmonary
Surfactant Deficiency
Premature
Alveolar Stability
Exogenous Administration
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Host Defenses
Cellular Immunity
WBCs
Phagocytosis
Adherence
Killing
Decreased Stores
Poor Stem Cell Production
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Host Defenses
Immunoglobulins
IgG crosses the placenta
Poor Response to Antigen Challenge
IgA and IgM
No type specific Antibodies
Decreased Complement System Function
Increased Mortality with Pyogenic BacterialInfections
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Surgical Stress Response
Initially Poorly Understood
Crude Monitoring
Few Outcome Studies
Myths
Anesthetics Unsafe/Not Approved
Pain
Could Anesthesia Blunt Surgical Stress
Response?
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Surgical Stress Response
Measured Catecholamines, Insulin, Cortisol.
Adult Physiology
Levels Decreased when Anesthesia
Administered
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