Studydroid is shutting down on January 1st, 2019



keywords:
Bookmark and Share



Front Back
Creatinine
  • Normal 0.8-1.2 serum level
  • predictors of Creatinine production
  • Muscle mass
  • age - inversely related
  • sex
Problems with Creatinine
  • Filtered and secreted
  • CrCl is overestimated
  • normal individuals
  • chronic and acute kidney disease - tubular secretion may increase with glomerular damage keeping Cr levels normal
  • severe hepatic disease
  • Metabolisms- increased with chronic renal disease
  • in severely reduced kidney failure 2/3 of cr excretion can occur by extra renal elimination
Factors altering Serum Creatinine
  • Kidney Disease - Increases
  • Reduced Muscle Mass - Decreases
  • Ingestion of cooked mean - increases
  • Trimethoprim/cimetidine - increases, inhibits tubular secretion
  • flucytosine/cephalosporins - increases, interference with assay
  • ketoacidosis - increases, interference with assay
Blood Urea Nitrogen
  • derived from hepatic deamination of AA
  • eliminated by kidneys through glomerular filtration and undergoes reabsorption in proximal tubule
  • dependent on
  • protein catabolism
  • dietary intake
  • liver dx
  • blood in GI tract
  • steroid induced catabolism
  • BUN/SCr ratio normal 10:1, 20:1 indicates prerenal
  • BUN follows reabsorption of water
Urinalysis - Color
  • normal : faint yellow
  • yellow-brown, deep olive green: bilirubin
  • brown to black: old blood, myoglobin
  • smoky: RBC
Urinalysis - turbidity
  • Normal: clear
  • formed substances (crystals, blood cells) make it appear turbid
Urinalysis - pH
  • normal 4.5-7.8 acidic to neutral
  • need freshly voided urine
  • becomes more alkaline with standing
  • more alkaline may indicated presence of UTI - urea splitting bacteria
Urinalysis - specific gravity
  • normal 1.003-1.030
  • measure of concentrating ability
  • close to one
Urinalysis - Na excretion
  • normally kidney reabsorbs 99% of filtered sodium in proximal tubules
  • not being reabsorbed indicates renal damage and diuretics
  • FENa = (UNaxPCr)/(UCrxPNax100)
  • prerenal will be <1% and urine Na <20 mEq/L
  • ATN 0 FENa >2% and urine Na >40 mEq/L
  • no diuretics within 12-24 hours
Urinalysis - protein or albumin
  • normal - none
  • can occur with excessive exercise or expsoure to cold
  • common characteristic of most glomerular dx
  • all pts with chronic kidney dx and thos with risk factors should be tested q12mo
  • proteinuria- albumin + other proteins
  • albuminuria - better indicator of early kidney dx
  • microalbuminuria 30-300mg/24 hr
Dipstick
  • qualitative
  • sensitive but not specific
  • validate within 3 months with quantitative test
  • if + 2 times confirmed
  • Microalbuminuria - red positive
Dipstick false positive
  • fluid balance - dehydration
  • hematuria  - increases protein in urine
  • exercise - increases protein excretion
  • infections- increased protein production from microorganism
  • pharmaceuticals -  alkaline pH may lead to false color on dipstick
Dipstick false negative
  • increased hydration - decreased protein in urine
  • other urine proteins - won't react as strongly as with albumin
Quantitative methods
  • Random urine for albumin-to-creatinine ratio
  • first morning urine for albumin-to-creatinine ratio
  • timed overnight urine for albumin excretion
  • timed 24 hr albumin excretion - gold standard
Urinalaysis - Sediment Bacteria
  • infection
WBC in urine
  • UTI
  • tubulointerstitial nephritis
Epithelial cells
  • normal
Eosinophils
  • pyelonephritis
  • interstitial nephritis
  • inflammation
RBC
  • glomerulonephritis
  • lupus
  • neoplasms
  • damage
Casts
  • RBC - glomerular, renal parenchyma or vascular bed damage
  • WBC - inflammatory process
  • granular - dehydration, ATN, glomerulonephritis, interstitial
  • Tubular - ATN
  • Hyaline - glomerulonephritis, pyelonephritis
  • crystals - usually not significant (inflammation, infection, metabolic) post renal
Urinalysis Glucose
  • normally absent
  • present if exceed max threshold for glucose reabsorption >180 mg/dL
Urinalysis Ketones
  • Acetoacetate and acetone
  • present in diabetic ketoacidosis
  • during fasting or starvation
Urinalysis Nitrites
  • formed by urinary bacteria - gram neg E. coli
  • possible UTI
Uninalysis Leukocyte esterase
  • released from lysed granulocytes in urine
  • possible UTI
Which of the following indicate UTI
  • Leukocyte esterase
  • positive nitrite
  • alkaline pH
Imaging Studies
  • Renal angiography
  • ultrasound
  • iv urogram (IVU) or iv pyelogram (IVP)
  • computerized tomography (CT)
  • magnetic resonanace imaginig (MRI)
Renal Angiography
  • uses contrast for assessment of renovascular dx
  • like an xray
  • visualization of kidney
  • see blockage or tumor
Ultrasonography
  • echogenicity of kidney compared with adjacent organ
  • tumor
  • obstruction
  • is there something solid there
IVU
  • inject contrast material into a vein in the arm
  • series of x-rays are taken at timed intervals
  • evaluate the condition of the kidneys, ureters and bladder
  • catheterization of kidneys
  • how is blood flow into and out of kidneys
CT
  • 3d reconstruction of tissues
  • flow
  • obstruction
  • malignancy
  • contrast sometimes used
Magnetic Resonance Imagning
  • uses magnet to apply radiofrequency pulses allows tissue image
  • contrast sometimes given
  • obstruction
  • malignancy
  • renovascular lesions
  • MOST SPECIFIC
  • most expensive
Biopsy
  • facilitates diagnosis when less invasive studies are unsuccessful
  • specific for glomerularnephritis
  • last line
Chem 7
Na/Cl/BUN (20)
K/bicarb (22-26)/SrCr    Glucose
Medication adjustment for renal failure
  • Metformin - D/C when SrCr >1.4 for females or 1.5 for males
  • sitagliptin - adjust
  • IBU - D/C, use APAP
  • metoclopramide - adjust to 5mg
Acute Kidney Injury
  • increase in SCr of more than 50% in a pt with previously normal renal function
  • increase of 1mg/dL with preexisting renal dx
  • increase of >0.5mg/dL with baseline SCr of <3mg/dL
Acute Renal Failure Mortality
  • Liver Dx
  • hypoalbuminemia
  • mechanical ventilation
  • heart failure
  • advanced age
  • contrast
Risk/Severity Non-oliguria
  • Risk - aburpt decrease >25% of GFR or SCr x 1.5 sustained
  • Injury - adjust cr or GFR decrease >50% SCr x 2
  • Failure - adjust cr or GFR >75% SCr x 3 or SCr <4 when acute increase >0.5
  • Loss - irreversible AKI or persistent AKI > 4 weeks
  • ESRD > 3 mo
Risk/Severity oliguria
  • decreased UO relative to fluid input
  • risk - <0.5 mg/kg/hr x 6 hr
  • injury - UO <05.mg/kg/hr x 12 hr
  • failure - uo <0.5 mg/kg/hr x 12 hr, anuria x 12 hr
  • loss - irreversible AKI or persistent AKI > 4 weeks
  • ESRD > 3 months
Classification
  • Community acquired - before hospitalization, most due to blood flow
  • hospital acquired - general ward usually drug related, ICU more prevalant and severe
Baseline Risks
  • advanced age
  • DM
  • chronic kidney insufficiency
  • HF
  • liver dx
  • genetic variation
  • hypoalbuminemia
  • arterial vascular dx
acute clinical condition risk factors
  • sepsis
  • hypotension/shock
  • volume depletion
  • rhabdo
  • cardiac/vascular surgery
  • non-renal transplants
  • mechanical ventilation
Nephrotoxic agent risk factors
  • contrast
  • antimicrobial (gent)
  • chemotherapy
  • NSAIDs
  • antiviral medications
pre-renal
  • volume depletion
  • hemorrhage
  • volume depletion
  • relative decrease blood volume- CHF, Cirrhosis
  • artery stenosis
  • hemodynamic form- medications
  • surgery - anesthesia, reduced MAP
Intrinsic Renal Failure
  • Vascular - vasculitis, malignant HTN
  • Glomerulonephritis - postinfectious, glomerulonephritis, immune mediated
  • interstitial nephritis- drug induced, infection
  • ATN - most common
  • ATN ischemic - antibiotics, contrast, cisplatin
  • ATN nephrotoxic - pigments, proteins, crystals
post renal
  • obstruction
Assessment
  • abnormal urinalysis
  • urine/blood chem
  • hx
  • co-morbidities- age, baseline renal insufficiency, diabetes, sepsis, mechanical ventilation
  • medication hx - OTC/herbals
  • volume status - dehydration/hypotension
Clinical presentation GI
  • anorexia
  • N/V
  • diarrhea
  • hiccups
  • ABDOMINAL PAIN
Clinical Presentation CV
  • hypertension
  • anemia
  • edema
  • arrhythmias
  • chest pain
  • palpitations
Clinical presentation respiratory
  • SOB
  • dyspnea
  • Kussmauls respiration - DKA
Clinical presentation Neuro
  • change in consciousness
  • thinking
  • memory
  • slurred speech
  • insomnia
  • resless leg syndrome
x of y cards Next > >> >|