Flashcards in Week 8.1 - Maternal problems in Pregnancy Deck (37)
Describe the cardiovascular changes which occur in pregnancy
-Blood Volume increases (upto 50%) therefore CO, SV and HR all increase
What happens to BP during pregnancy?
-Decreases in T1/T2 normal in T3 (systolic never increases)
What effects will pregnancy have on preload and afterload and why?
-Preload will increase as CO is increased, increased vol of blood returning to heart
-Afterload should decrease if BP decreases as TPR will decrease
Why is hypotension experiences in T1 and T2?
-Progesterone causes relaxation of smooth muscle in BVs therefore decreasin TPR
What could be a potentially dangerous cause of hypotension in T3?
-Aortocaval compression by enlarged uterus reducing venous return to the heart
Name one possible outcome of the bvs not vasodilating during pregnancy
-Pre-eclapsia -> uncontrolled hypertension with endothelial dysfunction
What changes occur in the urinary system during pregnancy?
-Glomerular filtration rate increases thus renal plasma flow increases and functional renal reserve decreases
What causes the increase in GFR during pregnancy?
What happens to creatinine clearance during pregnancy? Why?
-Because GFR has increased
What happens to urea excretion during pregnancy? Why?
-Because GFR increases
\Why is it important to know the normal for pregnancy range of creatinine and urea?
-May look like they are in the normal range when they are in fact high for pregnancy as more urea and creatinine should be excreted, therefore there may be a problem with the kidneys
What is the range of creatinine clearance during pregnancy?
What is the approximate value of urea during pregnancy?
Why is it significant that bicarbonate decreases during pregnancy?
-Reduced buffering capacity of the kidney
What is a potential problem which progesterone can place on the urinary system?
-Increasing GFR so much that hydroureter develops
Name a common cause of urianry stasis during pregnancy?
-Obstruction of ureter by gravid uterus
Why are UTIs concering during pregnancy?
-Possible to develop to pyelonephritis and cause pre-term labour
Name the anatomical changes which occur within the respiratory system during pregnancy
-AP and transverse diameters of the thorax increase
Name the physiological changes which occur in the respiratory system during pregnancy
-Physiological hyperventilation due to increased CO2 production and increased respiratory drive effect of progesterone
How is physiological hyperventilation of pregnancy compensated for?
-Increased bicarb excretion to compensate for the respiratory alkalosis
What are the changes in the capacities of the lungs during pregnancy?
-Reduced functional residual capacity but total lung capacity remains unchanged
-Increased TV with RR unchanged
What happens to O2 consumption during pregnancy?
-Increases by 20%
Why is vital capacity unchanged during pregnancy?
-VC = TV+IRV+ERV
although TV increases ERV volume decreases so VC remains unchanged
What happens to carboydrate metabolism during pregnancy?
-Increased peripheral resistance to insulin by hPL and the body switched to gluconeogenesis and alternative fuels to spare glucose for fetus
-Decreased fasting blood glucose
-Increased post-prandial blood glucose
List some risk factors for gestational diabetes
What is gestational diabetes?
-Increased blood glucose during T3 due to improper insulin response which doesnt persist post partrum
What is the outcome on the fetus of poor control of gestational diabeted?
-Macrosomic fetus, still birth, congenital defects
What happens to lipid metabolism during pregnancy?
-Increased lipolysis for T2
-Increased plasma free fatty acids on fasting to spare glucose for fetus
Why is pregnancy associated with a risk of ketoacidosis?
-If there is inappropriate lipolysis excess FA can get converted to ketones
What happens to thyroid metabolism in pregnancy?
-Thyroid binding globulin, T3 and T4 increase so free T4 in normal range
-Decreased TSH due to the effects of hCG
Describe the anatomical changes to the GI tract during pregnancy
-Alterations in the disposition of the viscera eg appendix moves to RUQ as uterus enlarges
Describe the physiological changes which occur in the GI tract during pregnancy
-Smooth muscle relaxation by progesterone -> delayed emptying -> constipation
-Biliary tract stasis
-Increased risk of pancreatitis
Describe the haematological changes which occur during pregnancy
-Prothrombotic state with increased fibrin deposition at implatation site and increased fibrinogen and clotting factors in blood.
-Reduced fibrinolysis and changes in vascular flow due to venodilation
Why cant you give warfarin in thromboembolic disease of pregnancy?
-Warfarin can cross the placenta and is teratogenic
What causes anaemia during pregnancy?
-Plasma volume increases more than red cell mass -> physiological anaemia
-Can also be due to Fe or folate deficiencies
Describe changes in the immune system during pregnancy
-Non-specific suppression of the local immune responses at the materno-fetal interface