Renal

Question 1

What are the physiological changes to the renal system in pregnancy?

Answer 1

• Increased kidney volume, weight and size. Bladder capacity doubles by term to 1000mls
• Progesterone = relaxation of bladder trigone
• Maternal and placental hormones increase plasma volume and alter renal function > 50-80% in glomerular filtration rate
• Oestrogen = bladder mucosa becomes hyperplastic + increased blood supply =oedematous = more vulnerable to trauma and infection
• Increased blood flow = 50% increase in glomerular filtration rate

Question 2

What changes are associated with increased GFR and tubular function in pregnancy?

Answer 2

• Increased excretion of solutes although tubular reabsorption increases to prevent the depletion of essential electrolytes
• Decrease tubular glucose reabsorption means glycosuria is a common finding
• Sodium filtration is increase but reabsorption increases also = net retention of sodium
• Increased excretion of water soluble vitamins
• Increased secretion of creatine, uric acid + nitrogen in urine
• Decrease in serum levels of urea, blood urea nitrogen, creatinine + uric acid
• Alteration in renal excretion of drugs

Question 3

What are the altonomic alterations in renal functions in pregnancy?

Answer 3

• Renal dilatation due to progesterone = increase the size of the kidney + ureters leading to a reduction in urinary flow combined with decreased bladder tone = tendency to urinary stasis
• As the uterus enlarges the urinary bladder is displaced + pressure from the uterus obstructs flow of urine
• Change in the angle that the ureters enter bladder = urine reflux
  ^^All of these predispose women to UTIs and pyelonephritis^^

Question 4

What are the mechanical problems in pregnancy + puerperium?

Answer 4

• Frequency
• Incontinence
  . stress following nerve damage to pelvic floor
  . urinary retention with overflow
  . vesicovaginal fistula due to obstructed labour/ instrumental
• Urinary retention
  . bruising/ oedema/ trauma to urethra/ bladder
  . over distension of bladder during labour
  . frequent catheterisation in labour

Question 5

What are Urinary tract infection symptoms?

Answer 5

• Dysuria caused by inflammation from increased WBC
• Offensive smelling urine
• Urinary frequency due to the UTI inflammation causing stretch signals to work improperly and signal wrongly to the brain
• Urgency
• Lower back pain caused by leucocytes in the urine which inflame the lining go the bladder and ureters

Question 6

Diagnosis of UTI

Answer 6

MSU for urine microscopy + culture

Question 7

Treatment of UTI

Answer 7

Prompt treatment with ABs to reduce risk of developing pyelonephritis