physiological changes in pregnancy

Question 1

mention the cardiovascular changes in pregnancy

Answer 1

• pregnancy is a high flow low resistance state
• cardiac output increases by 30 to 50%
• stroke volume increases by 30%
• plasma volume increases by 50% going from 2.5 later to 3.75
• early on in pregnancy stroke volume increases first then towards the end heart rate increases
• heart rate increases by 15-25% about 20 bpm
• blood pressure goes down during pregnancy
• blood pressure is inverse to systemic vascular resistance
• arteries have less resistance and take less pressure to pump blood
• systemic vascular resistance decreases by 20%
• systemic vascular resistance leads to a shunt away from other organs and toward important organs such as the kidneys thyroid placenta
• diastolic pressure decreases more than systolic
• central venous pressure which is towards the lungs does not change femoral venous pressure increases due to compression from the gravid uterus venous pressure is also seen in inferior vena cava
• increase is not seen above the pelvis
• murmurs are not uncommon in pregnancy mostly systolic murmurs similar to aortic stenos ejection murmurs around the left sternal border due to increased flow
• diastolic murmur is not normal
• echocardiogram is harmless in pregnancy and should be the first line of investigation
• high cardiac output is a positive sign
• highest in left lateral position and lowest in supine

Question 2

hematological changes in pregnancy

Answer 2

• plasma and RBCs increase
• plasma increases more leading to a decrease in hematocrit ratio this can come off as an anemic reading
• plasma volume increases by 50% and RBCs increase by 20 - 30%
• dilution anemia
• although anemia can still occur during pregnancy
• estrogen mediates white blood cell count
• esr increase due to increase in gamma globulins
• during pregnancy there’s a shift in the immune system
• increase in antibodies leads to a higher esr
• increase in antibodies in pregnancy is due to a shift in cell-mediated immune system to humoral
• humoral mediated immunity can be transferred to the fetus unlike cell-mediated
• factors 7 8 9 10 increase
• pregnancy is a hypercoagulable state
• increase in coagulability is most likely due to venous stasis and endothelial damage from hormones
• coagilability is adaptive to prevent postpartum hemorrhage
• the risk of dvt risk of pathological states of pregnancy
• platelet count unchanged
• RBCs mass increases
• women with an inherited risk of hypercoagulability are at risk of placental vascular thrombosis preeclampsia gestational hypertension fetal complications sga = small for gestational age
• dvt walking is advised or numeric pressure
• iron and folate requirements double
• ida is the most common cause of anemia
• range of hematocrit goes down
• iron studies low ferritin foes up in pregnancy
• ferritin goes up in states of inflammation acute phase reactant
• low ferritin is diagnostic

Question 3

renal changes in pregnancy

Answer 3

• kidneys increases by 100%
• progesterone increases
  urethra diameter
• gfr increases by 50%
• plasma sodium remains unchanged due to increased aldosterone
• plasma bicarb decreases to help with respiratory alkalosis
• blood ph increases
• urine glucose increases may be due to human placental lactose
• risk factors for uti are increased uterus size increased urine glucose and mechanical factors such as compression which leads to urinary stasis
• slight proteinuria in pregnancy
• raas is activated to help with total body sodium it increases but due to an increase in plasma volume ratio remains unchanged

Question 4

endocrine changes in pregnancy

Answer 4

• estrogen increases the main form of estrogen that increase is estriol
• three variations of estrogen estradiol fertile years estrone menopausal years
• estriol is synthesized in the placenta fetal dheas made in fetal adrenal glands placenta enzyme convert it’s to estriol
• progesterone increases initially in early pregnancy it’s from corpus lute after in involutes it comes from the placenta
• pituitary size increases by 100% Sheehan’s syndrome
• adrenal size unchanged by more active cortisol increases by 2 to 3 x level steroid helps to mature fetal lung cortisol levels peak towards the end of pregnancy
• cortisol can cause depression-like symptoms and may contribute to postpartum depression
• thyroid hormone increases thyroid binding increases
• free thyroid remains unchanged
• human placental lactogen
• HCG peaks at 10 weeks
• prolactin gradually increases
• pregnancy is a hyperestrogenic state
• hpl = human chorionic somatommamaotropin
• hpl = stimulates lipolysis
• antagonizes insulin increasing serum blood glucose to give energy to fetus
• pseudo insulin resistance state

Question 5

gi changes in pregnancy

Answer 5

• progesterone and mechanical changes
• gastric motility ges tone and colonic motility decreases
• gastric emptying time increase
• colonic transit time increases
• decrease in ges tone leads to gastro reflux
• HCG high concentration can lead to nausea
• omeprazole PPI is not recommended the use of h2 inhibitors is preferred
• can also use metoclopramide also helps with gastric motility
• antiemetics doxylamine b6 and frequent snacking with severe morning sickness
• hyperemesis gravid arum is associated with a decrease of 5% in body weight more
• anesthesia complication due to stomach technically never being empty in pregnancy

Question 6

dermatological changes in pregnancy

Answer 6

• stria gravid arum due to stretching and increased cortisol levels
• linea nigra
• chloasma
• spider angiomata
• Chadwicks sign
• palmar erythema
• melanocyte-stimulating hormone can cross placenta baby may have lines nigra