Congenital + Genetic disorder, Electrolytes Imbalance Flashcards
Define Congenital Abnormality
• Any defect(s) present at birth/in utero d/t development errors during gestations
Define Teratogen
Any factor or agent which is present in environment of embryo/fetus that causes or can cause a birth defect
Note: A Few Examples
- Thalidomide-> limb defects (given for morning sickness)
- Alcohol – fetal alcohol syndrome
- A negative teratogens (something not there leading to defect) i.e. malnourishment
- Cigarette smoke and infections
- Rubella virus
Discuss Organogenesis and the critical period
Period of dev (generally 15-60 post conception) during which organs form. Different organs dev at different times over that period (FIG 7-12) This specific time is known as critical period for that organ.
4 Types of Genetic Abnormalities
o Monogenic (single gene) - see normal gene fx and defect
o Mitochondrial genes
o Complex trait (multifactorial)
o Chromosomal (problem in # or structure)
Types of Monogenic Disorders
Autosomal dominant
o 50% chance of inheriting, need just one defective gene
Autosomal recessive
o 25% chance of inherit disease, 50% carrying, 25% not effected, one is unaffected need both parents to have gene. Draw the boxes.
X linked recessive
o Males do not have 2nd x to provide normal trait, females do, males more likely to inherit diseases
Describe Mitochondrial Disorders
- 37 mito genes. Code for enzymes in the Respiratory chain
- Maternal inheritance
- Often mnfsts in neuro or muscular system as these two organ systems require highest amounts of energy
(may result in poor growth)
(MIt DNA in Male is in tail of spermatozoa )
Describe Complex Trait Disorders
- Polygenic (more then 1 gene)
* Genes and environment interact. i.e. a potential defective gene + enviro factor (smoking) = disease
Chromosomal Disorders- Types Numerical Abn
Euploidy= Complete sets of chromosomes
Aneuploidy- Numerical abn (extra chromosome in pair or one missing)
• Extra Chr in a pair= trisomy
• Missing Chr in a pair= monosomy
• Named by Chr # (Ex. Down syndrome is trisomy 21)
Notes
• 23rd chromosomes should be either xx or xy.
• Klinefelters’s syndrome- Male as xxy (1 in 500)
o See Fg 7-11
• Turner ‘s syndrome- Female (one x) X0 (1 in 3000)
o See fig. 7-10
Chromosomal Disorders- Structural Defect Types (Fig 7-7)
- Inversion- section of chromosome flips vertically taking up a different position
- Translocation- moved segment from one chromosome to the other
- Deletion – Section of one chromosome missing
Name the 3 basic fluid compartments in the bodies
Intracellular, Interstitial, vascular (highest volume)
Causes and Manifestations of Dehydration (AKA Volume deficit)
Causes-
Inadequate fluid intake
Excessive Gastro fluid losses (vomiting DIarrhea)
Excessive renal loss (diuretic therapy, hyperglycemia)
Excessive skin loss (fever, sweating)
Excessive 3rd space loss (edema, ascites, burns)
Manfst- Acute weight loss increase in Antidiuretic hormone Increased serum osmolality (increase Hct, BUN) Decreased vascular volume Decreased extracellular fluid volume Impaired temp. regulation
Define Edema and Discuss Causes
Edema is build up of fluid in interstitial space (from vascular space)
• Can be life threatening (i.e lung or brain fluid build up)
• Causes (31-1)
o High capillary HP (too much fluid out, not enough in)
o Low colloid OP (proteins balance decreases pull into vessels)
o Excessive capillary permeability
o Obstructed lymph flow
NOTE: These causes all relate to issues of transcapillary exchange
o 3rd spacing
• fluid accum in transcellular space
• not easily exchangebale
Discuss the basics of Transcapillary Exchange
- Hydrostatic pressure is push pressure (pushing against capillary wall)
- Osmotic pressure is pull pressure (from proteins/ electrolytes in blood)
- Both capillary and interstitial have HP and OP
- Normal circumstance- push from vessel is higher in arterial end, center net pressure is zero, Venous end – pressure is such that fluid moves back into vessel
- There is some fluid loss (not all fluid is reabsorbed) picked up by lymphatic system
Acid Base Imbalance- Why so Critical?
Describe pH (Values + Measures)
Blood pH is critical since proteins fx in a narrow range and are very sensitive to pH changes
Blood neutral is 7.4 (as measured persistently by ABG)
o If pH drops below 7.35 (Acidosis)
o If pH goes above 7.45 (Alkalosis)
Describe the Carbonic acid Bicarbonate buffer
The Equation
C02 + H20 h2c03 H+ + HCO3-
Left side lungs (expelling acidic C02, Right side kidney excreting acidic H+ and secreting basic HCO3 into blood )
o Concentration of reactant and products will determine direction
Allows compensation through lungs and kidneys to control pH
Respiratory imbalances
• CO2 elimination problems
• Impaired ventilation-> increase pC02 -> lowers pH (resp acidosis)
• Excess elimination of C02 -> decrease pCO2 -> increase pH (resp alkalosis)
Metabolic imbalance- fixed acids
• too much acid H+ in blood (Acidosis), too much base HCO3 in blood (alkalosis)
• too little acid being reabsord H+(alkalosis), too little base HCO3 to blood (acidosis)
NOTES:
Lungs are fast at changing pH, kidneys slower
o IF it involves carbonic acid (only volatile acid) it will be respiratory in nature
o IF it involves any fixed acid (hydrochloric acid or lactic acid) it is a metabolic
TX- oral or IV solution to normalize pH, but must deal with underlying issue
