Chronic Kidney Disease Flashcards
1
Q
What is the Epidemiology of Chronic kidney disease?
A
- Approx. 26 million Americans have CKD and millions of others are at increased risk for CKD
- Chronic kidney disease globally resulted in approx. 956,000 deaths in 2013 up from 400,000 deaths in 1990
- Black Americans are 3 times more likely to experience kidney failure
- Hispanics are 1 ½ times more likely to experience kidney failure
2
Q
What is Acute Kidney Disease?
A
- Rapid loss of kidney function (hours to days)
- Commonly reversible
- Usually caused by dehydration, blood loss, medication, IV contrast, obstruction
3
Q
What is
Chronic Kidney Disease?
A
- Progressive loss of renal function that persists for more than 3 months
- Commonly irreversible
- Usually caused by long-term diseases such as DM, HTN
4
Q
How does the Kidney Function?
A
- Regulation of water, minerals and acid-base status
- Removal of metabolic waste products from the blood and their excretion in the urine
- Removal of foreign chemicals from the blood and their excretion in the urine
- Secretion of hormones (Erythropoietin, renin, Vit D)
5
Q
What is the Pathophysiology of CKD?
A
- Underlying etiology (DM,HTN) causes hyperfiltration and subsequent nephron damage
- Hyperfiltration = increased flow through glomerulus and thus GM HTN and over time leads to hypertrophy of remaining viable nephrons
- Adaptations become maladaptive as the increased pressure and flow predisposes to distortion of glomerular architecture, sclerosis and loss of remaining nephrons
6
Q
What is Glomerular Filtration Rate (GFR)?
A
- Measure of how well the kidneys are removing wastes and excess fluid from the blood
- Calculated from the serum creatinine level using your age, weight, gender and body size
- The normal value for GFR is 90 or above
- A GFR below 60 is a sign that the kidneys are not working properly
- A GFR below 15 indicates that a treatment plan for kidney failure, such as dialysis or a kidney transplant is needed
7
Q
What is the Estimated GFR (glomerular filtration rate)?
A
-Cockcroft-Gault Equation:
CrCl = (140 – age) X (IBW)
Scr X 72
- Modification of Diet in Renal Disease Study (MDRDS) Equation:
1. 86 𝑥 〖(𝑃𝑐𝑟)〗^(−1.154) x 〖(𝑎𝑔𝑒)〗^(−0.203) - Multiply by 0.742 for women
- Multiply by 1.21 for African Americans
8
Q
What are the symptoms of CKD?
A
- No symptoms typically until stage 3 or 4
- Anemia
- Fatigue/weakness
- Decreased appetite with progressive malnutrition
- Nausea/vomiting
- Sleep problems
- Decreased mental sharpness/encephalopathy
- Muscle twitches and cramps
- Swelling of feet and ankles
- Pruritis
9
Q
What are the Clinical Manifestations Advanced Stages of Uremic Syndrome?
A
Symptomatic manifestations associated with Azotemia = the accumulation of urea and other nitrogenous compounds and toxins caused by the decline in renal function
10
Q
What are the Complications of progressive chronic kidney disease?
A
- Anemia
- Metabolic acidosis
- Derangements in vitamin D, calcium and phosphorus metabolism
- Volume overload
- Hyperkalemia
- Uremia
- Cardiovascular consequences
11
Q
What is the Approach to the patient with new renal dysfunction?
A
- Consider pre-renal, renal, post-renal etiologies
- Careful history (contrast exposure, meds, dehydration)
- PE
- Serum creatinine (GFR)
- Urine dipstick; microscopy & spot protein
- Renal ultrasound (consider other imaging)
- Urinalysis
- Consider checking for multiple myeloma (serum protein electrophoresis, urine protein electrophoresis)
12
Q
What is Serum Creatinine Laboratory Data?
A
- Waste product that develops from normal wear and tear on the body muscles produced at fairly constant rate and excreted unchanged by kidneys
- Normal levels vary depending on age, race, body/muscle size
- A creatinine level of greater than 1.2 for women and greater than 1.4 for men may be an early sign that the kidneys are not working properly
- As kidney function decreases, creatinine level rises
13
Q
What is Blood Urea Nitrogen
Laboratory Data?
A
- Measures the amount of nitrogen in your blood that comes from the waste product urea
- Urea is made when protein is broken down in your body.
- A normal BUN level is between 7 and 20
- As kidney function decreases, the BUN level rises
14
Q
What is CKD
Laboratory Data?
A
-24hr urine test
(Compares the urine creatinine to the blood creatinine to show how much blood the kidneys are filtering out each minute)
-Urinalysis (UA)
(Protein (albumin))
-Urine Microscopy
(Cells/casts/crystals)
15
Q
What is Hematuria?
A
- > 3 RBCs per high-power field on at least 2 occasions
- Conditions that can cause hematuria
Urologic malignancy
Urinary tract infection (UTI)
Can be seen in interstitial nephritis
Glomerulonephritis causes
Coagulopathy
Colic
HSP, SLE nephritis
16
Q
What is Proteinuria?
A
- > 150-160 mg/24hr
- > 1-2gram/24hr signifies underlying kidney abnormality, usually glomerular
- > 3.5 g/24hr is consistent with nephrotic range proteinuria
- 24hr urine collection vs random ‘spot’ urine sample (Urine protein/Urine Creatine ratio)
- For spot urine < 0.2 is normal
17
Q
What is Anemia?
A
- Occurs secondary to decreased production of EPO by the kidney
- After work-up for anemia, if no other explanation is found, then CKD is declared to be the cause
- EPO-stimulating agents should be provided if Hgb falls <10 mg/dL (goal 11-12 mg/dL) *higher goals are associated with increase mortality
18
Q
What is Vitamin D Deficiency?
A
- Secondary to decreased production of 1,25-OH vitamin D (active form/short half life) as kidney is responsible for 1-hydroxylation process
- Only measure 25-OH vitamin D as they represent the storage form (normal is > 30 mg/mL)
19
Q
What is Metabolic acidosis?
A
- Secondary to decreased bicarbonate reabsorption and generation by kidneys
- Treat with bicarbonate supplementation after bicarbonate falls < 18 mg/dL (target 22 mg/dL)
20
Q
What is Bone disease?
A
Secondary to abnormalities in the complex interaction between vitamin D, phosphorus, calcium and PTH
21
Q
What is Uremia?
A
- Hundreds of toxins accumulate
- Urea and creatinine are elevated and used as surrogate markers for toxins
- Systemic inflammation increases
22
Q
What are the Risk Factors to the development of CKD?
A
- Hypertension
- Diabetes mellitus
- Autoimmune disease
- Older age
- African ancestry
- Family history
- Previous episode of acute kidney injury
- Proteinuria
- Abnormal urinary sediment
- Structural abnormalities of the urinary tract
23
Q
What are the Most common causes of ESRD?
A
- Diabetic glomerular disease (44%)
- Hypertensive nephropathy (28%)
- Glomerulonephritis (6%)
- Autosomal dominant polycystic kidney disease (2%)
- Other cystic and tubulointerstitial nephropathy
24
Q
What is Diabetes Mellitus?
A
- Leading cause of ESRD
- Approx. 26 million Americans have diabetes
- 2014 CDC reported that about 40% of US adults will develop diabetes
- More than 224,000 people are currently living with kidney failure caused by diabetes
- Intensive insulin therapy to maintain hbA1c level <7.0% reduces progression of kidney disease
25
Q
Treatment for Diabetes Mellitus?
A
- Primary prevention
- Tight glucose control
- Diet/exercise
- *BP control <130/80, lowering the BP delays the onset of microalbuminuria
26
Q
What is Diabetic Nephropathy?
A
- Diabetic patient with the development of renal injury
- First sign – microalbuminuria
- Most common co-morbidity – hypertension
- Recommendations of ACEI/ARB treatment even in a normotensive patient with Diabetic Nephropathy due to renal protective properties
27
Q
What is treatment for Diabetic Nephropathy?
A
- ACEI/ARB’s – renal protective qualities
- Diuretic – addition of a second agent to aide in BP control
28
Q
What is Hypertension?
A
- Second leading cause of ESRD
- HTN accelerates the progression of CKD
- Controlling blood pressure slows down the decline in GFR
- Inhibiting RAAS is effective in lowering blood pressure and reducing microalbumiuria
29
Q
What is treatment for Hypertension?
A
-Salt and water restriction
(2-4g/d salt restriction to avoid CHF/edema (extra fluid))
- Weight loss
- Pharmacological therapies
- Goal of therapy = halt progression to hypertensive nephropathy
30
Q
What is Hypertensive Nephropathy?
A
- Develops in patients with proteinuria and hypertension
- Lowering BP Goals in a patient with CKD and HTN
31
Q
What is treatment for Hypertensive Nephropathy?
A
- Current guidelines advise caution with use of ACEI/ARB’s in the presence of renal impairment
- Evidence that these drugs are effective in reducing progression of CKD and reducing mortality/morbidity in patients with heart failure
- Recommend use of ACEI/ARB’s in stages 1-3 and those with proteinuria
32
Q
What is Chronic Kidney Disease Treatment?
A
- Primary Prevention
- Treat underlying disorder
- Dialysis
- Transplant
33
Q
When do you Refer to a Nephrologist?
A
- GFR < 30ml/min (CKD Stages 4 and 5)
- Rapidly progressive CKD
- Poorly controlled hypertension despite four agents
- Rare or genetic causes of CKD
- Suspected renal artery stenosis
34
Q
When to Dialyze?
A
- Acidosis
- Electrolytes: hyperkalemia, hyperphosphatemia, hypocalcemia, rarely hyponatremia
- Ingestions: overdose
- Overload: volume overload, especially on many IVs + anuria
- Uremia: many symptoms - CNS (asterixis, seizure, coma), platelet dysfunction (GI bleed, bleeding diathesis, coagulopathies), infectious risk, pleuritis/pericarditis (friction rub), pericardial effusion
35
Q
What is Dialysis?
A
- Process for removing waste and excess water from the blood, and is used primarily as an artificial replacement for lost kidney function in people with ARF or CKD (stage 5)
- Dialysis is regarded as a “holding measure” until a renal transplant can be performed or as supportive measure in those with acute kidney injury where a transplant unlikely/unecessary
36
Q
What is Hemodialysis?
A
- Ultrafiltration occurs by increasing the hydrostatic pressure across the dialyzer membrane
- This usually is done by applying a negative pressure to the dialysate compartment of the dialyzer
- This pressure gradient causes water and dissolved solutes to move from blood to dialysate, and allows the removal of several liters of excess fluid during a typical 4-hour treatment
37
Q
What is Peritoneal Dialysis?
A
- Peritoneal dialysis, a sterile solution containing glucose (called dialysate) is run through a tube into the peritoneal cavity, the abdominal body cavity around the intestine, where the peritoneal membrane acts as a partially permeable membrane
- Diffusion and osmosis drive waste products and excess fluid through the peritoneum into the dialysate until the dialysate approaches equilibrium with the body’s fluids
- Then the dialysate is drained, discarded, and replaced with fresh dialysate
- This exchange is repeated 4-5 times per day; automatic systems can run more frequent exchange cycles overnight
- Peritoneal dialysis is less efficient than hemodialysis, but because it is carried out for a longer period of time the net effect in terms of removal of waste products and of salt and water are similar to hemodialysis
38
Q
When is time for a kidney transplantation?
A
- end-stage renal disease (ESRD), regardless of the primary cause
- This is defined as a glomerular filtration rate <15ml/min/1.73 sq.m.
- The majority of renal transplant recipients are on dialysis (peritoneal dialysis or hemofiltration) at the time of transplantation
- Individuals with chronic renal failure who have a living donor available may undergo pre-emptive transplantation before dialysis is needed.
