Management of Patients with alterations in the Renal system C. Cummings RN, EdD
Anatomy • System includes the kidneys and entire urinary tract • 2 kidneys located behind the peritoneum, on either side of the spine • Weighs about 8 oz and the left if longer and narrower than the right
Kidney • Renal capsule- fibrous tissue • Renal cortex- outer tissue • Medulla-inner tissue with “fans” • Pyramids-12-18/kidney • Papilla-end of the pyramid • Calyx-collects the urine at the end of the papilla • Renal pelvis- calices form it and leads to ureter
Renal blood flow • Kidneys receive 20-25% of the total cardiac output • Blood flow is 600-1300 ml/min • Renal artery comes off of the abdominal aorta • Exits off the renal vein and into the IVC
Nephrons • Functioning unit of the kidney • Urine is formed from blood • 1 million nephrons • Blood comes from the afferent arterioles, enters the glomerulus • Leaves by efferent arterioles
Nephron parts • Bowman’s capsule surrounds the glomerulus • Proximal convoluted tubule • Loop of Henle • Distal convoluted tubule • Collecting ducts
Renin-angiotensin system • Renin is produced by the macula densa cells note changes in the distal convoluted tubules • Based on decreased BP, bld volume and bld NA levels • Renin changes angiotensinogen into angiotensin I, ACE changes it to angiotensin II
Angiotensin II • Leads to 4 main outcomes: • Increased Na concentration (aldosterone from adrenal cortex) • Increased serum Na level by tubular reabsorption of Na in ascending loop of Henle (constricts afferent arteriole to decrease GFR, if bld volume is low) • Allows fluid to be removed and increases Na concentration in the bld, if blood volume if normal (constricts efferent arteriole to increase GFR) • Enhances reabsorption of Na from DCT
Renal regulatory functions • Glomerular filtration- water, electrolytes, Cr, urea N and glucose are filtered • Blood, albuminis too large • Forms 180 L of filtrate/day or GFR=125ml/min • Regulated by constricting and dilating the afferent arteriole • When SBP goes below 70mm Hg, GFR stops (MAP of 60)
Tubular reabsorption and Secretion • Reabsorption • Most of the water and electrolytes are reabsorbed, 65% of filtrate to keep urine output at 1-3 L • Most of water reabsorption is in the PCT, some is in DCT • DCT is affected by ADH and aldosterone • ADH enhances water reabsorption by increasing membrane permeability • Aldosterone reabsorbs Na • Solute Reabsorption • 50% of urea, no creatinine • Most Na, Cl is reabsorbed in the PCT, some in the collecting ducts by aldosterone • K is reabsorbed in the PCT and the ascending loop of Henle • Bicarb, Ca and Phosphate are in the PCT • Glucose is reabsorbed up to 220mg/dl > will be excreted • Tubular secretion is substance need to be excreted, such as K and H
Renal hormones • Renin= RAAS (renin-angiotensin-aldosterone system) • Prostaglandins- PGE and PGI, regulate filtration and vascular resistance • Bradykinins-dilates the afferent arteriole and increase capillary membrane permeability • Erythropoetin-released when there is decreased oxygen, triggers RBC production in the bone marrow • Vitamin D activation- converted to its active form in the kidney
Renal Assessment • Personal history- what questions should we ask? • What about diet, why is that important? • What is a normal urine output? • What types of medical conditions can affect the kidneys?
Renal Assessment • Inspection- note any swelling or discoloration in the flank region, costovertebral angle is 12th rib and vertebrae • Auscultate for what? • How do you palpate the kidneys?, not be done is suspect pheochromocytoma, what is that? • Percuss what? Only the kidneys or bladder too?
Diagnostic tests • Blood • Creatinine- end product of muscle and protein metabolism (0.6-1.2) • BUN- excretion of urea N from protein metab, liver failure, trauma will elevate (10-20 mg/dl • Ratio BUN/CR is 12-20:1, dehydration can cause BUN to be elevated, but not CR • Decreased ratio will occur with FVE • Urine • Urinalysis for inspection, odor, cloudiness, pH, specific gravity • What is a normal S.G.? • What things would be abnormal in the urine? • How high is the bacterial count in order to be treated?
Diagnostic tests • IVP- intravenous pyelogram, now called IV urography • Given a contrast dye, should not give if pt has renal insufficiency • Shows the size, shape and location of kidneys • Patency of calices, pelves and ureters • Detects obstructions and masses
Diagnostic Tests • CT of the kidney • Renal Arteriogram
Diagnostic • Renal Biopsy • Check blood counts before procedure, may need to transfuse • Given procedural sedation • Monitor the site for bleeding 24 hours after, bruising on flank, H&H • Bedrest for 6 hours • Will have hematuria
Cystoscopy • Visualize the bladder and any abnormalities
Urinary Tract Infections • UTI’s are the most prevalent nosocomial infections, costing 1.6 billion/yr • How can they be prevented in the hospital? • What is the recommended length of time a catheter should remain in, in the acute care setting? • What factors may contribute to a UTI? • Which organisms are most commonly the cause of UTI’s?
Urinary Tract Infections • Cystitis- inflammation of the bladder, interstitial cystitis, unknown etiology • Can lead to urosepsis, has a high mortality and prolonged hospitalization • Incidence is greater in women than men and increases by 50% in women over 80
Case Study- UTI • 24 y.o. sexually active female, who arrives in the ED, complaining of frequency, urgency and dysuria. She has difficulty initiating a stream. This has been occurring for the past 3 days, but not she feels weak and has noticed some blood in her urine
Case Study • What type of questions may you ask this patient? • What type of urine sample would you get? • The urine comes back with > 100,000 c./ml • Should this be treated? What is the most common antibiotic that is given for an uncomplicated 3 day course?
Case Study • What nursing diagnoses would be appropriate for this patient? • What patient education should be done? • Include diet and prevention therapy
Urinary Incontinence • Incontinence- involuntary loss of urine • Not a normal result of aging • In the elderly, can be caused by: • Medications, disease, depression, unable to walk or get to the BR
Types of incontinence • Stress- most common, occurs during coughing, sneezing, jogging or lifting, weakening of the bladder neck can occur with childbirth, can’t tighten the urethra enough to overcome the urge to void • Urge- when they feel the “urge” to go, they can not hold it until they find a BR, called overactive bladder, can be caused by CVA, parkinson’s disease, MS, UTI, BPH, artificial sweeteners, caffeine, alcohol, diruetics, nicotine
Incontinence • Overflow- when the detrusor muscle fails to contract, the bladder becomes overdistended, leaks out to prevent rupture, may be urethral obstruction, diabetic neuropathy, pelvic surgery • Reflex- abnormal detrusor contractions r/t neurologic problems- CVA, spinal cord lesions, MS • Functional- loss of cognitive function in patients with dementia
Incontinence • 85% of all cases are women • Contributing factors are: • Medications- diuretics, opioids • Diseases- CVA, arthritis, parkinson’s • Psychological disturbances • Physical examination • Assess for bladder fullness- bladder scan, cystocele, note detrusor muscle
Incontinence- Interventions • Exercise- kegel’s strengthen pelvic floor • Weight reduction, decrease fluids at night • Drug therapy- estrogen, antispasmodics- ditropan, probanthine, bentyl, detrol, antidepressants- tricyclics- anticholinergics and alpha-adrenergics, so decrease urination • Vaginal cone- weighted cones to tighten muscles, pessary to hold bladder up in cases of cystocele
Incontinence- Surgery • Vaginal or retropubic surgery • Elevates the urethra, repairs cystocele • Postop- monitor voiding, may have SP catheter, PVR should be less than 50ml, monitor for bleeding
Incontinence education • What type of education should be provided for bladder training? • How can you get the family to help? • If the patient does need to straight cath or have a foley at home, what things should they monitor for?
Renal Calculi- Urolithiasis • Nephrolithiasis- stones in the kidney • Ureterolithiasis- stones in the ureter • 75% of the stones contain Ca- Ca oxalate or Ca phosphate • 15% struvite, 8% uric acid and 3% cystine • 90% of patient have a metabolic risk factor for the stones • Incidence is higher in men
Renal calculi • Formation is from • Slow urine flow from the element, such as Ca • Damage to the lining of the tract • Decreased inhibitor substances in the urine that would dissolve
Renal Calculi Risk Factors • Hypercalcemia- • Increased intake or renal failure • Hyperparathyroidism • Immobilization • Hyperoxaluria- • genetic trait that overproduces • Excess intake from spinach, rhubarb, coca, beets, wheat germ, pecans, okra, chocolate • Hyperuricemia- • Gout with purine metabolism disorder • Increased purines from cancers and thiazide diuretics • Struvite- • Magnesium ammonium phosphate and carbonate, urea splitting bacteria causes • Cystinuria- • Genetic defect of amino acids
Renal Calculi • Symptoms: • Renal colic- what is that? • Oliguria vs anuria, what is the difference? • What is the predominant nursing diagnosis? • Interventions: • Drug therapy: • Pain relief, what should be used? • Besides opioids, what medication may be helpful? • Lithotripsy- • Shock wave therapy to break up stones • Monitor ECG, bleeding after • Strain the urine for stone collection
Surgical interventions • Nephrolithotomy and ureterolithotomy • Endoscope or lithotriptor to grasp and extract the stone • Nephrostomy tube is left in place • Keep the nephrostomy site sterile and never irrigate with more than 10 ml • May be performed as an open procedure if the stone is too large
Patient education • How can the patient prevent getting more stones? • What foods should be avoided if the patient has a calcium oxalate stone? A calcium phosphate stone? A struvite stone? A uric acid stone? • How much fluid should the patient take in per day?
Renal Disorders • Polycystic kidney disease- genetic disorder, cysts develop on the kidney, most patients are hypertensive, RAAS is activated • As the patient ages, kidney is more damaged • Controlled by monitoring the BP and using ACE inhibitors, control the cell proliferation of PKD, follow a low NA diet • Control for pain, many need a transplant
Glomerulonephritis • Third leading cause of ESRD • Disorders that cause are often autoimmune, such as: • Lupus, Goodpasture’s syndrome, Wegener’s granulomatosis, amyloidosis, diabetes, HIV, hepatitis C, cirrhosis, sickle cell disease, endocarditis • Infectious processes also cause, such as: • Beta-hemolytic streptococcus, Staph bacteremia, syphilis, pneumococcal mycoplasma or klebsiella, CMV, histoplasmosis, varicella, toxoplasmosis
Glomerulonephritis • An infection may precipitate • Symptoms occur 10 days • 75% of patients have edema of face, hands, eyelids • Fluid overload and circulatory congestion
Glomerulonephritis • Urine is smoky or reddish brown with hematuria and oliguria • HTN with wt. gain • Fatigue, anorexia, N&V • What kind of labs would be done? • What lab would be done to assess for a strep infection? • What type of 24 hour urine would be done?
Case Study- Nephrotic Syndrome • 8 y.o. presents to the hospital with swelling of the face and hands. He has the sickle cell trait. His mother has noted a marked decrease in his urine output and it looks dark brown. He complains of feeling tired and not wanting to eat.
Case Study • What process occurs with Nephrotic syndrome? • What would you expect to see in his urine? What about his lab values? • His mother asks if this condition can be cured, what would you say? • What type of treatment may be prescribed? Medications and therapy
Benign Prostatic Hypertrophy • Prostate become hyperplastic and enlarges with age • Prostate extends upward into the bladder and inward, narrowing the urethral channel • Obstructs urine flow, overflow incontinence • Bladder becomes irritable and leads to urgency and frequency, muscles enlarge and can lead to hydroureters and hydronephrosis
BPH • Symptoms: • Nocturia • Frequency, urgency • Reduced stream and force • Incomplete emptying and dribbling • Hematuria in elderly males • Assessment: • Digital rectal exam • Urinalysis • PSA level, what is this for? • What nursing diagnoses would be appropriate?
BPH • Medications: • Shrink- Proscar, finasteride, lowers DHT, may take 6 months to lower, major side effect is ED and decreased libido • Alpha-adrenergic blockers- Hytrin, Cardura, Flomax, constricts the prostrate and reduces pressure • Avoid medications that may cause urinary retention, such as anticholinergics, antihistamines and decongestants • Don’t take in a large amounts of fluid, avoid alcohol and diuretics, that can cause overdistention
BPH Surgery • TURP- transurethral resection of the prostate • Can only remove pieces of the prostrate in chip form • Suprapubic, Retropubic and Perineal prostatectomy- done when the prostate is large or the bladder also needs to be explored
BPH surgery • Postop: • Assess incision site if applicable for bleeding • Continuous Bladder irrigation (CBI) done 24 hours post surgery • Monitor for FVE, running total of I & O • Bleeding is to be expected, but urine should not be “frank” blood, may have clots, monitor H&H • May have bladder spasms, ditropan or B&O supp.
Renal Failure • Renal failure is the loss of function r/t nephron damage. In CRF, 90-95% of the nephrons are lost before failure is obvious • ARF, only 50% decrease in nephrons can cause failure, ARF is a sudden onset and may last < 3 mo, good prognosis • Most common causes of CRF are: • Diabetes (43%), HTN (25%), glomerulonephritis (8%)