Vascular and tubular components of the nephron
disorders that have a familial inheritance
- Bright's disease - nephritis - nephrosis - plycysytic kidney dis
Turbidity clear
- Cloudy urine infection - sediments - ↑ levels of urine protein
Ketones none
- DK - prolonged fasting - anorexia nervousa
UA color normal yellow
- Dark amber concentrated urine - very pale yellow dilute urine - Dark red blood in urine - Brown increased bilirubin - red myoglobin - other color diet and drugs
patient preparation and procedure care for Renal scan
- No fasting or sedation used - peripheral IV to give radioisotopes - maybe give furosemide or captopril better visualization - isotope eliminated 6 to 24 hrs after - encourage fluid
Glomerulus Capillary loops with thin, semipermeable membranes
- a site of glomerular filtration - glomerular filtration occurs when hydrostatic pressure (BP) is greater than opposite forces (tubular filtrate and oncotic press)
ultrasonography (US) can be used with dye
- a size of the kidneys - obstructions - tumor stones - lower UTI
Vascular componenets
- afferent arteriole - Glomerulus - efferent arterioles - Peritubular capillaries (PCT) - vasa recta (VR)
pH average 6 possible range 4.6 to 8
- changes caused by diet - drugs - infection - age of speciment - acid-base imbalance - KD
Changes in the renal system related to aging
- decreased GFR - Nocturia - Decreased bladder capacity - Weakened urinary sphincters and shortened urethra in women - a tendency to retain urine
Cystography and cystoscopy patient preparation
- endoscopy - checklist - signed an informed consent statement - may be under general anesthesia - local anesthesia with sedation - NPO - bowel preparation with laxatives or enemas before a procedure - ambulatory PACU - catheter after a procedure - encourage oral fluid to prevent clotting
metabolic imaginwith positron emision tomography PET kidneys
- evaluate cysts - tumors - other lesions - eliminating the need for biopsy in some patients
BUN/creatining ration abnormal findings ↑ ration
- fluid volume deficit - obstructive uropathy - catabolic state - high-protein diet
BUN/creatining ration abnormal findings ↓ ratio
- fluid volume excess
UA odor normal similar to amonia
- foul smell indicates infection, dehydration, or certain food or drugs
cystoscopy
- identify abnormalities of the bladder wall and urethral and ureteral occlusions - treat small obstructions or lesions via fulguration, lithotripsy, or removal with a stone basket
Bilirubin (urobilinogen) none
- liver or billary dis or obstruction
BUN abnormal findings increased
- liver or kidney dis - dehydration or ↓ kidney perfusion - high-protein diet - infection - stress - steroid use - GI bleeding - blood in body tissue
BUN abnormal findings decreased
- malnutrition - fluid volume excess - severe hepatic damages
CT scan kidneys
- measures size - evaluate contour to assess for masses - obstructions of kidneys or urinary tract - assess renal blood flow
Cystography
- outline bladder's contour when full and examine structure during voiding - examine the structures during of the urethra - detect backward urine flow
cystourethrography void during a procedure
- outline bladder's contour when full and examine structure during voiding - examine the structures during of the urethra - detect backward urine flow
Glucose - Fresh specimen = negative 50 to 300 mg/day in a 24-hour specimen
- presence hyperglycemia - ↓ in the kidney threshold for glucose
Kidney hormones
- renin - prostaglandins - Bradykinins - erythropietin - activated vitamin D
Radiography of kidney, ureters, and bladder (KUB) plain film abdomen
- screen for the presence of 2 kidneys - measures kidney size - detect gross obstructions - detect urinary tract obstruction
Radiography of KUB plain film of the abdomen - kidneys - ureters - bladder
- screen for the presence of two kidneys - measures kidney size - detect gross obstruction in a kidney or urinary tract
MRI kidneys
- useful for staging of cancer
Specific gravity 1.005 to 1.030 1.000 to 1.040 older ↓
- ↑in ↓ kidney perfusion - inappropriate ADH secretion - heart failure - ↓ in CKD - diabetes insipidus - malignant hypertension - diuretic administration - lithium toxicity
Tubular components
-Bowman's capsule (BC) -Proximal convoluted tubule (PCT) -Loop of Henle -Descending limb (DL) -Ascending limb (AL) -Distal convoluted tubule (DCT) -collecting ducts
Hormones influencing kidney function
-Vasopressin (ADH) -Aldosterone -Natriuretic hormones
Serum creatinine females
0.5 to 1.1 mg/dL (0.44 to 0.097) 44 to 97 osmolarity
Serum creatinine Males
0.6 to 1.2 md/dL (0.053 to 0.106) 53 to 106 osmolarity
BLood urea nitrogen
10 to 20 mg/dL (3.6 to 7.1 mmol/L) Older adults 60-90yrs 8 to 23 mg/dL (2.9 to 8.2 mmol/L) Older than 90 yrs 10 to 31 mg/dL (3.6 to 1.1 mmol/L)
BUN/creatinine ration
6 to 25 (BUN divided by creatinie
Efferent areterioles delivers arerial blood from the glomerulus into the peritubular capillaries or the vasa recta
Autoregulation of renal blood flow via vasocontriction or vasodilation renin-producing granular cells
Metformin should be discontinued at least 24 hrs before for at least 48 hrs after the procedure contrast induces nephrotoxicity increase fluid intake sodium bicarbonate in a liter of IV fluid or oral acetylcysteine prevents nephrotoxic
CT sacn with contraste
NPO for some period before scan DYE use may be omitted in patients at risk for contrast-induced acute kidney injury - ensure sufficient oral or IV intake to dilute and excrete the dye - fluid intale of 1 L to mainatin output 1 to 2 mL/kg/hr X up to 6 hrs - no postprocedure care
CT scan kidneys
Metal implants - pins - pacemaker - joint replacement - aneurysmal clips - other cosmetic or medical devices Gadolinium-based contrast causes nephrogenic system fibrosis
MRI kidneys
Vasopressin (ADH) released from the posterior pituitary
Makes distal convoluted tubule and collecting ducts permeable to water maximaize reabsorption and produce a concentrated urine
Tendency to retain urine Provide privacy, assistance, and voiding stimulants such as-as warm water over the perineum as needed
Nuring intervntions can help voiding
Parasites none
Presence of TRchomonas vaginalis - infection - usually irethra - prostate - vagina
Activated vitamin D Kidney parenchyma
Promotes absorption of calcium in the GI tract
Aldosterone released from the adrenal cortex
Promotes sodium reabsorption in DCT and CD potassium secretion in DCT and CD
tell the patient that the x-ray will be taken while he is in a supine position - no specific follow-up care is needed
Radiography of kidney, ureters, and bladder (KUB) plain film abdomen
Renin Renin-producing granular cells
Raises BP - angiotensin (local vasoconstriction) secretion - aldosterone (volume expansion secretion
Collecting ducts collect formed from several tubules and deliver it into the renal pelvis
Receptor sites for antidueretic hormone regulation of water balance
Descending limb continuous from the loop of Henle
Regulation of water permeable - water - urea - sodium - chloride
Proximal convoluted tubule Evolves from and is continuous with Browman's capsule Specialized cellular lining facilitates tubular reabsorption
Site for reabsorption of - Sodium - chloride - bicarbonate - phosphate - urea
Decreased GFR = ensure adequate fluid intake
The kidneys are less able to conserve water when necessary
- full bladder - prone position
US
Leukoesterase none
UTI
Nitrites none
Urinary E. coli
Tendency to retain urine Observe the patient for urinary retention (bladder distention) urinary tract infection (dysuria, foul odor, confusion)
Urinary stasis may result in a UTI, which may lead to bloodstream infection, urosepsis, or septic shok
Renal scan (nuclear)
_ evaluate renal perfusion - estimate glomerular filtration rate - provide functional information without exposing the PT to iodinated contraste dye
↓ bladder capacity respond as soon as possible to the patient's indication of the need to void
a quick response may alleviate episodes of urinary stress incontincence
Distal convoluted tubule Evolves from AL and twist so the macula densa cells lie adjacent to the juxtaglomerular cells of afferent areterioles
a site of additional water and electrolytes reabsorption - barcarbonate - potassium - hydrigen secretion
Tendency to retin urine Evaluate drugs for possible contribution to retention
anticholinergic drugs promote urinary retention
dietary supplements with synthetic creatine used to increase muscle mass
as been associated with compromised kidney fucntion
Afferent arterioles Delivers arterial blood from the branches of the renal artery into the glomerulus
autoregulation of renal blood flow via vasoconstriction or vasodilation - Renin-producing granular cells
NSAIDs or acetaminophen
can seriously reduce kidney function
Gentamicin - Garamycin - Cidomycin
cause acute kidney injury -
Natriuretic peptide hormone cardiac atria cardiac ventricle brain
cause tubular secretion of sodium
Bowman's capsule Thin membranous sac succounding 7/8 the glomerulus
collects glomerular filtrate (GF) and funnels it into the tubules
Decreased GFR = administer potentially nephrotoxic agents or drugs carefully
dehydration reduces kidney blood flow and increases the nephrotoxic potential of many agents acute to chronic kidney failure may result
Decreased bladder capacity encourage the patient to use the toilet, bedpan, or urinal at least Q2H
emptying the bladder on a regular basis may avoid overflow urinary incontenence
Nocturia discourages excessive fluids intake for 2-4 hrs before the patient goes to bed
excessive fluid intake at night may increase nocturia
Nocturia - ensure adequate nighttime lighting and a hazard-free environment
fall and injures are common among older patients seeking bathroom fcilities
Hypertension
hematuria proteinuria
Bradykinins juxtaglomerular cels of the arterioles
increase blood flow (vasodilation) and vascular permeeability
Drug-drug interaction dye interactions
lead to kidney dusfucntion
serum creatinine older adult
may be decreased
Crystals none
presence the specimenthas been allowed to stand
Prostaglandins kidney tissue
regulates intrarenal blood flow by vasodilation or vasoconstriction
Loop of Henle Continuous from PCT Juxtamedullary nephrons dip deep into the medulla
regulation of water Permeable - water - urea - sodium chloride
Nocturia Rvaluate drugs andtiming
some drugs increase urine output
Erythropoietin Kidney parenchyma
stimulates bone marrow to make RBCs
Decreased GFR = monitor hydration status
the ability of the kidneys to regulate water balance decreases with age
uremia
the buildup of nitrogenous waste products in the blood as a result of some degree of kidney impairment manifestations - anorexia - NA?VO - muscle cramps - pruritus (itching) -fatigue - lethargy
Weakened urinary sphnicter and shortened urethra in women Provide throrought perineal care after each voiding
the shortened urethra increase the potential for a bladder infection Good perineal hygiene may prevent skin irritation and UTI
Thik Ascending limb Emerges from DL as it turns and redirected up toward the renal cortex
this segment is impermeable to water Permeable - potassium - magnesium
Peritubular capillaries surround tubular components of cortical nephrons
tubular reabsorption and tubular allow movement of water and solutes to or from the tubular, interstitial, and blood
vasa recta surround tubular components of juxtamedullary nephDelivers arterial blood from the branches of the renal artery into the glomerulus nephrons
tubular reabsorption and tubular allow movement of water and solutes to or from the tubular, interstitial, and blood
Nocturia - ensure the availibity of a bedside toilet, bedpan, or urinal
using these items instead of getting up to a bathroom can help prevent falls
casts none
↑ - bacteria - protein - urinary calculi
WBCs 0 to 4 low-power field
↑ - infection - inflammation in kidneys and urinary tract - kidney transplant rejection - exercise
Bacteria < 1000 colonies/mL
↑ - need for the urine culture to determine UTI
RBCs 0 to 2 high-power filed
↑ - normal with catheterization or menses - tumor - stones - trauma - glomerular dis - cystitis - bleeding dis
Protein 0 to 0.8 50 to 80 in a 24-hour specimen at rest < 250 mg in a 24-hour specimen with exercise
↑ - stress - infection - recent strenuous exercise - glomerula disorders
serum creatinine abnormal findings
↑ kidney impairment ↓ decreased muscle mass
