Med Surg Exam 1 Flashcards
Antidiuretic hormone (ADH)
Controls how much fluid leaves the body in urine and causes reabsorption of water.
Aldosterone
Reabsorption of water and sodium
Renin
Released when there is a decreased blood flow to the kidneys.
Osmosis
Movement of liquid across membrane. Water moves by osmosis. When there are differences in concentration of fluids, osmotic pressure will move water from lesser concentrated to more greater concentrated until they are equal.
Diffusion
Substances move across the membrane until they are evenly distributed.
Filtration
Movement of water & solutes by pushing force on one side of the membrane. (Pressure)
Isotonic
Equal solute concentration
Hypertonic
Greater concentration (cell shrinks)
Hypotonic
Less concentration (cells swell)
The most accurate measure of fluid gain or loss for any age group
Weight change (1kg = 1 L of fluid)
S/S of dehydration
Thirst
Poor skin turgor
Rapid, weak, thready pulse
Slightly elevated temp
Increased hematocrit
High urine specific gravity with low volume
S/S of overhydration
Weight gain
Slow, bounding pulse
Firm subcutaneous tissues
Crackles in lungs
Lethargy, possible seizures
Decreased serum sodium
Decreased hematocrit from hemodilution
Low urine specific gravity with high volume
Older Adult Care Point on volume deficient
Age-related decline in total body water and decrease thirst sensation and taste. If urinary incontinence is a problem, the person becomes reluctant to drink extra fluids. THIRST IS A LATE SIGN OF DEHYDRATION IN OLDER PATIENTS.
Fluid volume deficient contributes to
Constipation
Orthostatic hypotension with related dizziness and falls
Makes the person more susceptible to infection
Measuring BP & Pulse (orthostatic ir postural hypotension)
A systolic BP drop of 20 accompanied by a pulse rate increase of 10 BPM at 1 min after position change suggests a fluid deficit.
Older patients (rehydration)
Rehydrate cautiously. Any pt who has cardiac problems is at risk for fluid overload from IV infusions. Infuse slow. If IV infusion falls behind DO NOT try to infuse at a faster rate than ordered.
Normal hematocrit values
35-54 mL of RBC per 100mL of whole blood, depending on age and sex. If excess water, less RBC due to dilution by water
Specific gravity ranges
1.010 - 1.025 (urine concentration)
Sodium values
135-145
Potassium Values
3.5 - 5
Calcium Values
9 - 10.5
Magnesium Values
1.5 - 2.5
Phosphate Values
2 - 4.5
Chloride Values
98 - 106
Hyponatremia S/S
CNS & neuromuscular changes, fatigue, lethargy, headache, mental confusion altered LOC, anxiety, coma, anorexia, nausea, vomiting, muscle cramps, seizures, decreased sensation, decreased BP
Hypernatremia S/S
Dry mucosa, taut skin turgor, intense thirst, flushed skin, oliguria, possibly elevated temp., weakness, lethargy, irritability, twitching, seizures, coma, intracranial bleeding, low-grade fever
Hypokalemia S/S
Abdominal pain, paralytic ileus, gaseous distensión of intestines, cardiac dysrhythmias, muscle weakness, decreased reflexes, paralysis, urinary retention, increased urinary pH, lethargy, confusion, ECG changes
Hyperkalemia S/S
Muscle weakness, fatigue, hypotension, nausea, parenthesias, paralysis, cardiac dysrhythmias, ECG changes
Hypocalcemia S/S
Paresthesias, abdominal cramps, weak pulse, decreased BP, seizures, muscle spasm, positive Chvostek sign, positive Trousseau sign, cardiac dysrhythmia, wheezing, dyspnea, difficulty swallowing, colic, cardiac failure, excessive blood transfusions
Hypercalcemia
Anorexia, nausea, abdominal pain, constipation, muscle weakness, oliguria, confusion, renal calculi, pathological fractures, dysrhythmias, cardiac arrest
Hypomagnesemia S/S
Insomnia, hyperactive reflexes, leg/foot cramps, twitching, tremors, seizures, cardiac dysrhythmias, positive Chvostek & Trousseau sign, vertigo, hypocalcemia, hypokalemia
Hypermagnesemia S/S
Hypotension, sweating and flushing, nausea and vomiting, muscle weakness, paralysis, respiratory depression, cardiac dysrhythmias
Hypophosphatemia S/S
Confusion, seizures, numbness, weakness, possible coma, chronic state: rickets and osteomalacia
Hyperphosphatemia
Anorexia, nausea, vomiting
Foods high in sodium
Buttermilk
Casserole & pasta mixes
Catsup
Cheese (all kinds)
Frozen vegetables with sauces
Prepared mustard
Softened water
Tomato or vegetable juice
Foods high in potassium
Baked potato with skin
Orange juice
Pinto beans
Spinach
Tomatoes
Winter squash
Raisins, seedless
Normal pH
7.35 - 7.45
Respiratory acidosis
Slow, shallow respirations
Respiratory congestion or obstruction
pH <7.35
PaCO2 >45
Metabolic acidosis
Shock (poor circulation)
Diabetic ketoacidosis
Renal failure
Diarrhea
pH <7.35
HCO3 <22
Respiratory alkalosis
Hyperventilation
pH >7.45
PaCO2 <33
Metabolic alkalosis
Vomiting
Excessive antacid intake
Hypokalemia
pH >7.45
HCO3 >26
Dextrose in Water
5%
Isotonic
10%
Hypertonic
Saline
0.45%
Hypotonic
0.9%
Isotonic
Multiple Electrolyte Solutions
Ringer solution
Isotonic
Lactated Ringer
Isotonic
Control of fluid is balanced by
Hormones and thirst mechanism
The kidney is a major factor in the
Regulation of fluid and electrolyte balance in the body
Edema can be treated with
Diuretic medications, low sodium diet, elastic stockings and compression devices
TPN is used when
A patient cannot obtain adequate nutrition by other means
PaCO2 normal ranges
(Partial pressure of carbon dioxide)
35 - 45
HCO3
(Bicarb)
22 - 28
3 mechanisms that balance pH
- Buffer systems
- Respiratory system
- Renal system
Respiratory acidosis
pH <7.35
PaCO2 >45
Causes:
Airway obstruction, pneumonia, asthma, chest injuries, pulmonary edema, COPD, opiate use that depresses the RR
Metabolic Acidosis
pH <7.35
HCO3 <22
Causes: diarrhea, renal failure, diabetic ketoacidosis, hyperkalemia, sepsis
Respiratory Alkalosis
pH >7.45
PaCO2 <35
Causes: anxiety, high fever, overdose of aspirin
Metabolic Acidosis
pH >7.45
HCO3 >26
Causes: vomiting, GI suction, hypokalemia, excessive use of antacids with bicarbonate
Glucose range
70-110
Creatinine normal values
0.5-1.2
Blood Urea Nitrogen (BUN)
10-20
pH urine
4.6 - 8
WBC in urine
0-4
The kidneys
- Regulate the electrolytes
- Eliminate metabolic wastes
- Regulate fluid volume
- Assist in acid base balance
- Regulate BP
- Metabolize vitamin D
Age-related changes (urinary)
- Kidney function degrades (GFR)
- Secretion of renin, aldosterone, vit D decrease
- Bladder muscles weaken, may lead to residual urine & incontinence
- Decrease ability to concentrate urine
Examples of potentially nephrotoxic substances
Antiinfectives
ACE inhibitors (captopril)
Antineoplastic agents (cisplatinmethotrexate)
Immunosuppressants (cyclosporine)
NSAIDs (salicylates, ibuprofen)
Other drugs (acetaminophen, furosemide)
IV contrast media
Heavy metals (lithium, gold salts, lead)
Environmental (pesticides, snake venom)
Recreational drugs (cocaine, heroin)
Dysuria
Pain or discomfort during urination. (Burning)
Usually caused by inflammation in either the bladder or the urethra.
Renal biopsy
Purpose: to diagnose the cause of kidney disease, to detect cancer
Procedure: local anesthesia is given, needle is inserted into kidney using ultrasound (10 min procedure)
Preparation: NPO for 6-8hrs, blood tests done prior
Postoperative care: must lie on back for 6-24hrs, expect blood in urine for first 24 hrs. Drink 3000mL to flush urinary system
Home instructions: avoid strenuous activity, report bright red bleeding, dysuria
Urinalysis
To detect bacteria, blood, casts, and other abnormalities of the urine.
Blood urea nitrogen (BUN)
To evaluate kidney function and hydration status.
High levels can indicate poor kidney function, dehydration or increased breakdown of body protein)
Lower levels are found in severe liver damage, excessive hydration, and protein deficiency.
Serum creatinine
To evaluate kidney function.
Creatinine is a waste product, excreted by the kidneys.
BUN/creatinine ratio
To help distinguish between renal causes and normal causes of abnormal values.
Levels of BUN in the blood are 10-20x higher than creatinine. BUN levels change due to multiple conditions. Creatinine stays relatively constant.
Kidneys, ureters, bladder (KUB)
To visualize the urinary structures or radiopaque stones.
Single radiographic view of the lower abdomen done without contrast medium.
Intravenous pyelogram (IVP)
To visualize the kidneys, ureters, bladder. To detect obstructions related to stones or tumors. Rarely used; CT and ultrasound more common.
An iodine-based contrast is given via IV injection, then radiographs are taken at timed intervals, showing the flow of the contrast through renal system
Cystogram
Can be done with contrast as a voiding cystogram. Can be done with radioactive material — radionuclide cystogram also called a bladder scan.
To visualize the contour of the bladder.
Radiographs are taken before and after sodium iodine is instilled into the bladder through urethral catheter. Or a radionuclide is instilled into the bladder through the catheter, and scanning is done
Renal angiography
To assess renal arterial system function and identify areas of obstruction to blood flow.
Under local anesthesia, a catheter is threaded through the femoral artery and up the aorta to the renal artery, and a contrast agent is injected. Angiography is preformed to detect complications in a transplanted kidney, to evaluate mass, or to check the extent of kidney trauma.
Cystoscopy
To examine the interior of the bladder.
Under short-acting or local anesthesia, a cystoscope is passed up the urethra into the bladder. The scope can be guided into a ureter to extract a stone or to biopsy lesions in the bladder. Sedation may be needed.
Urethral pressure study
To determine urethral pressure needed to maintain urinary continence.
A small catheter with pressure sensing capabilities ie inserted into the bladder. As the pt voids, the varying pressures of the smooth muscle of the urethra are recorded.
Renal biopsy
To obtain tissue specimen to determine causes of renal disease, to check for malignancy, or to evaluate extent of transplant rejection.
Pt is placed in prone position with pillow under abdomen. A local anesthesia is given. CT or ultrasound is used to identify the position for biopsy needle insertion into the lower lobe of the kidney. The pt must hold breath while needle is inserted and withdrawn. A tissue sample is extracted and sent to the lab.
Hematuria definition
Blood in urine
Cystitis
Inflammation of the bladder
Anuria definition
Absence of urine.
Pts with chronic renal failure who are on dialysis.
Oliguria definiton
Diminished or abnormally decreased flow of urine.
May result from dehydration, renal failure, or obstruction. Urine output less than 400mL/day
Polyuria definition
Abnormally high and dilute urine output.
The result of excessive solutes and increased excretion of water. Possible causes include hypercalcemia, diabetes insipidus, uncontrolled diabetes mellitus, increased fluid intake
Nocturia definition
Urination that occurs during the night
May be related to decrease ability of the aging kidney to concentrate urine.
