Bioscience in Pregnancy 2 Flashcards
Which valve is most commonly affected by rheumatic fever?
Mitral valve (bicuspid)
What early pregnancy changes may mask or decrease hypertension? What hormone is responsible?
Progestrone.
-reduces vascular resistance
-reduces blood pressure
In which of the following heart conditions are the systemic and pulmonary circulations completely seperate?
Transposition of the great arteries
Which of the following are defects found with tetralogy of fallot?
VSD
pulmonary stenosis
right ventricular hypertrophy
over-riding aorta
Which of the following cardiac conditions involves narrowing of the aorta
coarctation of the aorta
Coronary artery disease involves blockage of… and is the leading cause of ….
coronary artery disease involves blockage of CORONARY ARTERIES and is leading cause of ISCHEMIC HEART DISEASE
Rheumatic fever is caused by a strep A throat infection and usually leads to…
Mitral valve stenosis
Describe how pregnancy is likely to impact on wahine with a structural heart defect, particularly one that has not been treated previously?
Increased workload on the heart throughout pregnancy- requires increased CO to deliver increased blood to the developing structures/fetus.
Pregnancy is likely to exacerbate any existing cardiac condition and will require
referral.
How may hypertension be affected during pregnancy and what are two risks for mum and baby of hypertension during pregnancy?
Hypertension may be hidden in early pregnancy due to decreased vascular resistance- progesterone relaxes the smooth muscle in vessels.
Risks include: IUGR, preterm or still birth, cardiac or renal failure, stroke
What is the most likely cause of a pulmonary embolism?
Deep Vein Thrombosis
Name 4 physiological factors that increase the risk of DVT?
-blood vessel damage
-increased fibrinolysis
-hypercoaguability
-blood stasis
Pregnancy, labour and the puerperium are all significant risk factors for DVT formation. Using your understanding of pregnancy physiology and the pathophysiology of DVT, explain why pregnancy, labour and the puerperium increase the risk of DVT formation.
Blood stasis is more likely to occur during pregnancy due to the relaxation of blood vessels and increased blood volume (this can be exacerbated by increased pressure on the IVC from the gravid uterus).
During pregnancy, labour and the puerperium the woman is in a hypercoaguable state, increasing the risk of clot formation.
Endothelial (blood vessel) damage occurs during labour due to placental separation (and possibly other trauma), stimulation clot formation in the puerperium.
List the risk factors for DVT
- Pregnancy
- Smoking
- operative birth
- Reduced mobility/immobilization
- Relaxation of blood vessels due to progesterone
- Operative birth (c/section)
- Increased clotting factors and decreased clotting time
- Immobility in late pregnancy or after birth
Explain why DVT increases the risk of pulmonary embolism.
Because a DVT may be dislodged to become a free-floating embolus in the blood. This embolus will travel from the deep veins, through larger and larger veins back toward the heart, eventually being pumped into the pulmonary circulation by the right ventricle. It will continue to float through the pulmonary vasculature until it enters a pulmonary artery/arteriole it is too small to fit through, and it becomes lodged, blocking pulmonary blood flow beyond that point.
What is the most common form of anemia during pregnancy?
Describe the pathophysiology of this type of anemia and the potential implication for the woman during pregnancy, labour and the puerperium.
Iron-deficiency anemia.
If there is not enough iron (eg dietary insufficiency) then not enough
hemoglobin made, as each hemoglobin molecule requires four iron atoms. Without enough iron and hemoglobin there is a decreased oxygen carrying capacity of RBCs. Pregnancy enhances iron-deficiency anemia as hemodilution reduces hemoglobin concentration and there are increased iron needs during pregnancy, especially later in pregnancy.
This can lead to maternal tiredness/exhaustion- not enough ATP can be made by body cells. It may also decrease fetal growth/development as not enough o2 available. Women with anemia are at increased risk of hemorrhage during labour/pp- small blood loss can lead to hemodynamic compromise due to the already reduced carrying capacity of blood.
During which phase of hypovolemic shock is there likely to be a high HR and RR, but low BP and pulse?
Phase III (decompensation)
Compensatory mechanisms which would normally follow haemorrhage or dehydration include: (2)
Decreased urine output,
increased activity of the sympathetic nervous system
Why might some wahine with asthma experience an improvement in their condition during pregnancy?
Due to the smooth muscle relaxing (progesterone) that cause bronchodilation
Describe the pathophysiology that occurs in response to an asthmatic trigger.
An asthmatic trigger stimulates bronchoconstriction and inflammation and swelling of the lining of the airway with increased mucosal production. These lead to increased airway resistance, making ventilation difficult and resulting in a decrease in oxygenation and a ventilation-perfusion mismatch. If not treated, this can lead to hypoxia of body tissues and respiratory acidosis.
Coeliac disease is an inflammatory condition of the mucosa of the small intestine that is induced by:
Gluten containing foods
Cystic Fibrosis results in thickened body secretions due to:
abnormalities in chloride channels in cell membranes
Secretion of which ion is affected in cystic fibrosis?
Chloride (Cl-)
Morbidity with cystic fibrosis mostly occurs due to the effects on which body system?
Respiratory system is associated with the greatest morbidity in CF.
what are the chances of a neonate of a wahine with cf being a carrier or developing cf?
All children of a woman with CF with be a carrier (if it is an autosomal
recessive trait) and there is a 50% chance of each child developing CF if the father is also a carrier (and 100% chance if the father also has CF)
ˆWhy is conception advised during a period of remission for women with either ulcerative colitis or Crohn’s disease?
Because conception during active infection is associated with a greater likelihood of continued active disease during pregnancy which is associated with increased risk of miscarriage, IUGR, preterm birth.
For each of the pregnancy hormones listed below, describe how they increase the likelihood of gallstone formation during pregnancy;
Estrogen
Progesterone
Estrogens- increase cholesterol production and cholesterol saturation in bile Progesterone- relaxes the gallbladder and biliary duct system, reducing the bile flow
and increasing bile stasis.
Gallstones form when there is increased concentration of bile wit cholesterol, thus
both estrogens and progesterone increase the likelihood of bile concentration in the gallbladder.
What activities are likely to enhance the pain associated with symphis pubis dysfunction (SPD)?
-walking
Taking the stairs
Moving from sitting to standing position Standing on one leg
Rolling over in a bed
Getting in/out of a car
What are common symptoms to PID, endometriosis and PCOS?
Hypermenorrhea (heavy menstrual bleeding) Infertility
Painful intercourse
Abnormal hair growth
Hursutism is…
male pattern hair growth associated with polycystic ovarian syndrome.
Why does PID increase the risk of ectopic pregnancy?
With repeated inflammation of the upper reproductive tract, the formation of significant scar tissue and adhesions reduce fallopian tube motility (eg. Peristalsis and cilia sweeping action) and may even partially or completely block the fallopian tubes, reducing or preventing movement of the fertilized ovum into the uterus prior to implantation
What reproductive disorders can lead to infertility?
-PID
-Endometriosis
-PCOS
What impact are skin conditions likely to have for pregnant women, labour and postpartum period?
May decrease the comfort/quality of life
-Increased ‘flares’ of the condition due to increased blood flow to the skin during pregnancy
-Increases the likelihood of interventions during labour
-Reduces the risk of infections in the postpartum period
What is pubis symphysis dysfunction and what advice might you give a woman who develops this during pregnancy?
Excessive relaxation of the ligaments of the pubic symphysis causing pain that is exacerbated by weight bearing activities.
Possible advice; avoid activities that exacerbate the pain, avoid abducting the legs as much as possible, use support when moving from sitting to standing position, refer to physiotherapy, recommend use of a trochanteric belt, if none of these work, mild analgesics for pain relief
Myasthenia Gravis:
Is an autoimmune disease that destroys Ach receptors in skeletal muscle
