Neonatal case conference Flashcards
Gestational Age
number of weeks of pregnancy from last normal menstrual period
AGA
(Appropriate for Gestational Age)-birth weight between the 10th and 90th percentiles for a given gestational age
SGA
(Small for Gestational Age)-birth weight less than 10th percentile for the given gestational age
LGA
> 90th percentile for the given gestational age
LBW
Low Birth Weight Infant)- an infant who weighs less than 2,500 grams
VLBW
(Very Low Birth Weight Infant)- less than 1,500 g
preterm
less than 38 weeks gestation
term
38-42 weeks gestation
post term
more than 42 weeks gestation
infant death
a death occurring any time from birth to but not including 1 year of age
perinatal death
a death occurring between the 28th week of gestation and the 28th day of life
Total Body Water (TBW)
considerations in the newborn
In early fetal development TBW constitutes almost 95 % of total body weight
At birth in the term infant TBW is approximately 75% of the total weight
During the first week of life term infants will typically loss about 10% of their birth weight
After decreased urinary output in the first 24-48 hours a diuresis occurs with loss of extracellular water
In preterm infants the weight loss can be up to 15%
Sodium Balance in the Newborn
Total sodium content determines the volume of ECF. So renal sodium handling is a critical component in maintaining proper volume
Sodium is freely filtered by the glomerulus and almost completely reabsorbed in the tubular system
In term infants, like adults fractional sodium excretion is less than 1%
In preterm infants sodium loss is inversely proportional to gestational age, with infants at 28 weeks gestation having fractional excretion at 5-6%
Parameters Associated with Fluid Management in the Newborn
Urine output-1-3 ml/kg/hr
Hypernatremia- Sodium > 150mmol/L
Hyponatremia-Sodium less than 130mmol/l
Signs of excessive water loss
Excessive wt loss Dry oral mucosa Sunken anterior fontanelle Capillary refill > 3seconds Tachycardia Decreased BP Metabolic acidosis
A 10 day old male infant presents to the ED with lethargy, poor feeding and decreased urine output.
What are your initial thoughts/concerns?
Sepsis Metabolic defect (IEM) Intracranial bleed Hypoxic/ischemic encephalopathy Feeding difficulties/Dehydration Renal malformations Renal vein thrombosis
Definition of ARF in the newborn is based on
a rapid elevation in the concentration in the blood of BUN, creatinine and other cellular waste products resulting from diminished GFR
Cannot define a specific creatinine level to call ARF as measurements immediately after birth reflect the mother’s creatinine as well as the infant
Normal creatinine levels depend on gestational age
Urine output can be used as an indicator of ARF-usually less than 0.5 ml/kg/hour
Prerenal Causes of acute renal failure in the newborn
Sepsis Hypovolemia Hemorrhage Hypoxia/Ischemia Cardiac Failure Hypotension Hyperviscosity
Renal (Intrinsic ) Causes of ARF in the newborn
ATN (ATI)
- Hypoxia-ischemia
- Toxins
Drugs
- Aminoglycosides
- Contrast Agents
ACE inhibitors
Vascular
- Renal vein or artery thrombosis
Congenital parenchymal disease
Maternal drugs
Transient acute renal failure of the newborn
Post Renal Causes (Obstructive) of renal failure in the newborn
Congenital obstruction
- Ureteral
- Urethral
- Bladder
- Pelvic mass
Calculi
Hypernatremic dehydration in the neonatal period
is well described arising from disproportionate deficit of body water relative to body sodium coupled with the extracellular water loss that occurs in this age range
Most common cause is lactation failure
Infants can loose water through the skin at a rapid rate, especially with non bullous ichthyosis
