Transcript Document
Week 8
seminar
Urinary System Disorders and
Calculating ‘Desired-Doses’
(chapter-28 and chapter-9)
The Urinary System
Made up of Organs which form & excrete urine
(see Fig.28-1 on pg 585)
(2)
Kidneys
(2)
Ureters
Bladder
Urethra
Common symptoms of Urinary
System Disorders
Anorexia, Nausea, Vomiting
Fatigue, Lethargy, Malaise
Dysuria, urgency, frequency, hematuria
Pain in lower-back (kidney area), flank (sides)
Fever, disorientation
Common Side-effects of Rx’s for
Urinary System Disorders
Drying of secretions
Drowsiness, dizziness, sedation
Rash, hives, ‘urticaria’
GI effects (nausea, vomiting, diarrhea)
Headache
Discoloration of urine (see Table 28-1, p.585)
UrinarySystem DRUG therapy
See Chart @ top of page-584 in Textbook
Diuretics – modify kidney function
Electrolytes/Fluids (“replacement therapy”)
(see Table 28-2 on page-586) … examples …
Sodium
Potassium
Calcium
Magnesium
… more detail, next slide
Electrolyte imbalance effects
Electrolyte
level
symptoms
SODIUM
high
Edema, thirst, high temp, flushing
low
Stomach-cramps, vomiting, diarrhea
high
Abdominal-distension, diarrhea
low
Paralysis, weakness, muscle function
high
Anorexia, nausea, coma, weakness
low
Muscle-cramp/twitching, numbness/tingling
of fingers, toes, lips
high
Flushing, sweating, low temp, cardiac
depression
low
Abnormal heart rhythms, neurotoxicity
POTASSIUM
CALCIUM
MAGNESIUM
Urinary Tract Infections (UTI)
Most common bacterial infection in the U.S.
10 – 20% of females have a UTI during
lifetime
E.Coli causes ~90% of all cultured UTI’s
Upper UTI (kidneys/ureters) - symptoms
include> *lower-back/flank pain *fever
*headache *nausea/vomiting
Lower UTI (bladder/urethra) - symptoms
include> *frequency *urgency *dysuria
*hematuria *oliguria *incontinence
Some causes of UTI’s
Anything that results in urine being ‘held’ in the
bladder (more common in females …sorry ladies!)
If you gotta go … you BETTER go!
Dietary factors – certain foods (see Box 28-1 p587)
Enlarged Prostate (males) – constricts the
urethra, causing urine to be ‘retained’ in the
bladder
Female ‘Plumbing’ – due to the short length of
urethra, and the proximity of the urethra, vagina,
and the anus
UTI - Drug Therapy
Anti-Bacterials (sulfa-drugs, trimethoprim)
kill bacteria, in the urine and systemically
Anti-septics (Macrobid, methenamine)
antibiotic activity ONLY in the urine !
Analgesics (Pyridium, AZO-standard otc)
by topical and local anesthesia on the lining of
the urinary-tract
--- Study --- Table 28-3 on page 589
UTI – RX patient ed
Sulfonamides (sulfa-drugs) – take on
empty-stomach with a full glass of water
Drink plenty of water throughout the day
(eight to ten 8-oz glasses if on a sulfa-drug)
If taking sulfa-drug, avoid prolonged
exposure to sunlight, unless using a good
sunscreen !
Complete entire course of UTI drug
treatment … even if symptoms improve !!!
More UTI-drug patient ed
Pyridium (phenazopyridine) – changes urine
color to orange-red color! May stain clothing
Cranberry juice, Vit-C, prunes make urine
more acidic, making antiseptics more effective
Carbonated drinks, citrus fruits make urine less
acidic, making antiseptics less effective !
FEVER after starting the drugs may be a sign of
a drug-reaction, not a UTI-symptom
small, spastic-like bladder (‘tiny-tank’)
that empties automatically when filled
to a certain point
Tofranil (imipramine) – anti-depressant
DDAVP (desmopressin) – an anti-diuretic
that actually increases the reabsorption
of water -----available as a Nasal-spray,
or tablet
Time for
Calculating Doses
(oral, nonparenteral)
the main 3 calculation methods
--- Ratio-and-Proportion
method
--- Formula-Method
--- Dimensional-analysis
Choose the ONE method that you’re most
comfortable with … and stick with it !
Why go with ONE method ?
…you will become very familiar
with your ‘chosen’ method
… this will reduce the chance of
medication errors that may occur
from switching between calculation
methods !
Basic Rules for confident calculating
(see Box 9-1 on p.166 … dosage-forms)
Always check UNIT’s (numerator/denominator)
Always work the problem ON PAPER, even the
math seems EASY
Check and RE-CHECK all Decimals, Fractions
LOOK at the RESULT! …does it look reasonable,
does it make sense?
Take ONE LAST LOOK to make sure you
calculated dose in the correct units
Box 9-1(p.166) Dosage-forms
Know which types of dosage-forms can be
divided, halved, altered
Scored tablets – okay to break
Oral – syrups and liquids – okay to alter
Timed-release (sustained, delayed) – DO NOT
BREAK or ALTER THESE ! … this can significantly
change the rate of the drug’s dissolution
(dissolving) and its absorption
“labeling” the parts of the
problem
“DA” = dose-available, what is ‘on-hand’
“DO” = dose-ordered, what you ‘want’
“DF” = dosage-form, of the ‘on-hand’
“DG” = dose-given, this is the unknown-amount
of the on-hand drug that we are calculating …
this is the ‘X’ that we are solving for.
Ratio-and-Proportion
Units must match … numerator/denominator
Ratio examples: 60-minutes/1-hour
Proportion examples: 60min/1hr = 120min/2hr
Let’s try one!: how many minutes in 2.5 hours ?
a) we are looking for
b) we know that
x minutes/2.5 hours
60min/hr (60min = 1hr, written as fraction)
… see next slide … )
(
Ratio-and-Proportion
Let’s try one!: how many minutes in 2.5 hours ?
1st: we are looking for
x minutes/2.5 hours
2nd: we know that 60min/hr …(60min = 1hr, written as
fraction) so set-up the problem as xmin/2.5hr = 60min/hr
3rd: now we cross-multiply x-min x 1-hr = 2.5hr x 60min
4th: ‘hr’s cancel, leaving: x = (2.5)(60min) = 180 minutes …
our final answer, which makes sense! 2-1/2 hours is 60min +
60min + 30min = 180 minutes.
Formula - method
“DA” = dose-available, what is ‘on-hand’
“DO” = dose-ordered, what you ‘want’
“DF” = dosage-form, of the ‘on-hand’
“DG” = dose-given, this is the unknown-amount
of the on-hand drug that we are calculating
Always check that the strengths of the drug-
ordered (DO) and the drug-available (DA) are in
the same-unit-of-measure!
Formula-method cont.
Look at page-171
Example #3, then Example #4
Ask yourself … (also, page-171)
--what the Dr. ordered (DO)?
--what strength is available (DA)?
--what is the unit of measure (DF)?
--how much do we need to give (DG)?
REMEMBER ! … 1-grain = 60-mg (gr i = 60 mg)
Dimensional - analysis
Look at page-173 of Textbook
Once learned, this is a very good system
Try a few examples in your Textbook
May be the ‘one for you’ !
QUESTIONS
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