Renal And Urinary System Flashcards
What is the glomerular filtration rate
Volum of filtrate formed by both kidneys aeach minte
How does GFR change
Increase by 40-50%
What causes GFR to change
Progesterone Andrea in cause vasodilation increasing blood flow to the glomerulus
Increased GFR deuces levels of creating urea and uric acid in the bloood
It’s needed to handle the increases preduction of uric acid by the placenta and fetus
What happens to the blood pressure
Decreases
What happens if the systolic bloood pressure fall below 80
Auto regulation fails which impairs kidneys ability to filter
MAY not be reversible
What happens if blood pressure increases
Hypertension can be cause of renal disease
Disrupts renal function if renal blood vessel damage causes ischeamia - lack of o2
Reduced blood flow stimulate the RAA raising the blood pressure further
what changes in reabsorption
Blood volume increase and blood vessel dilate
Increasing progesterone ncreases GFR and reduces vascular resistance \increasing relaxin causes vasodilation and increase ADH
Increase hCG responsible for increased levels of ADH and increased levels of thirst = increased blood volume and decreased plasma sodium levels
What is polydipsia
Excessive thirst
What is polyuria
Excessive urination > 3 litres a day
Although pregnant women usually wee more often its rarely polyuria
What is proteinuria
Urinary protein excretion bigger 300mg/24 hours
Proteinuriain more detail
Usually large protein molecules acannot pass through the filtration system in the glomerular capsule
In preganancy there is an increased GFR increased permeability and impaired reabsorption i thetubule. So th protein through filtration system and is not re absorbed into the the blood
What does proteinuria suggest
Pre eclampsia. In the presence of raised blood pressure or renal disease
What is hematuria
If read blood cells are present in urine the filtration in the kidneys may be impaired as these larger cells have made their way through the semi permeable membrane .
Potential cause - inflammation of glomerulus
Glycosuri
Usually 100% of glucose is reabsorbe in the tubule. In pregnancy, glucose reabsorption is less effective and may exceed the reabsorption capacity
This may result in glycosuria
More than one high level of glycosuria refer for gestational diabetes
What is ketonuria
Presence of ketones in the urine
Suggests that fat is being metabolised rather than carbohydrates
May be associated with vomiting in preganancy or labour
May be also present in women with diabetes
What happen to the ureters
Gravid uterus compresses them which reduces urine flow from the kidneys to the bladder
Hat is mild hydronephrosis
Swelling of the kidneys due o a build up of urine
Common in 43-100% of pedant women
Most common at 28/40
Resulting from compression of uretesr and effects of progesterone on reduction of tone of hte ureters
Increased urinary stasis
Pyelonephritis
40% increase risk of pyelonephritis
An acre bacterial infection of the renal pelvis and calcyes causing small absences bacteria usually reaches the kidney by travelling up the urinary tract
The condition is usually accompanied by fever malaise and loin pain.
Infection o any part f the urinary tract (UTI) may spread upwards causing acute pyelonephritis - routine screening for asymptomatic bacteriura at booking appointment by sending off a mid stream urine sample for micro culture and sensitivity
What happens to the urinary bladder
In pregnancy the capacity of the bladder increases under the influence of the progesterone
In ealry pregnancy the growing uterus compromises bladder capacity. Women may report increase frequency of mictuition - urination
Enablement of the presenting part may reduce bladder capacity nd displace the bladder into the abdominal cavity during labour
Important to empty bladder regularly at least 4 hourly to avoid damage o the bladder and ureters
What is cystitis
Inflammation of the bladder
What is cystitis due to
Upwardspread of commensal bacteria of the bowel from the perineam via the urethra
Trauma following healthcare infection - eg radiotherapy insertion of urinary catheter
What are the effects of cystitis inflammation
Odeoma and small haemorrhages of the muscle hitch may be accompanied by th haematuria
The sensory nerve endings in the bladder wall become hypersensitive and ae stimulated even when the bladder contains only small Lou of urine leading to frequency of micturition and dysuria. Urine may be cloudy and have an unpleasant smell
Lower abdominal. Pain ofte accompanies cystitis
I untreated upwardspread may cause acute pyelonephritis or sepsis
Why might incontinence occur
Over disention of the bladder in labour, injury to pelvic floor during birth or weakening of the pelvic floor during pregnancy and birth . Unprepared second degree perineal injuries are associated with a higher incidence of incontinence during the menopause
Women should be educated on pelvic floor exercises
What is anuria
Absence of urine
Suggestive of renal impairment +/- abnormal fluid balance
Obliguria
Urine output less than 400ml per day.
Suggestive of renal impairement +/- abnormal fluid balance.
May be result of medications such as oxytocin which temporarily reduce urine output
Dysuria
Not normal
Pain on passing urine - burning suggestive of UTI or cystitis
Pain may be due to birth trauma
Nocturia
Passing urine in night
Common in pregnancy
Associated with increased glomerular filtration rate and sodium excretion in pregnancy. In 3rd rimester ma be due tto reduced functional capacity of the bladder
How to collect mid stream urine sample steps
- Ask woman to wash hands
- Aks woman to clean external genitalia if possible
- Provides with sterile pot
- Explain the procedure
- Ask the woman to begin urinating
- One she has passed a small amount of urine catch pat of the mid stream o the urine in the pot
- Once we has the sample continue to wee until bladder empty
- Label sample with patient info and send for micro culture and sensitivity
Hoe to perform urinalysis
- Wash and dry hands
- Insert reagent strip into urine and remove
- Tap th strip on the pot to remove excess urine
- Old strip next to the colour chart and exults in good light
- Dispose of urine
- Wash hands
- Discuss the findings and act accordingly
How to calculate fluid balance
- Add all fluids together entering the body - oral fluids iv fuids
- Subtract all fluids leaving the body - urine vomit blood
- Resulting figures is fluid balance
