Renal/Coagulation Flashcards
What are basic questions to ask for renal history?
- Have you ever had any kidney problem?
- Have you ever had kidney failure, dialysis, or more than two kidney infections?
- Have you ever had kidney stones?
- Are you undergoing dialysis for kidney problems?
- Have you had changes in bowel or bladder function in the last year?
- Has your appetite for food changed in the last year? (Voluntary avoidance of foods having a high protein content is a subtle sign of renal disease.)
In what situations will dialysis be required?
- Oliguria
- Fluid overload
- Hyperkalemia
- Severe acidosis
- Metabolic encephalopathy
- Pericarditis
- Coagulopathy
- Refractory GI symptoms
- Drug toxicity
CHEAPFDOG
What kind of access can be used for hemodialysis?
- AV fistula = cephalic vein anastomosed to radial artery
- Jugular or femoral vein for emergency access
What are some considerations with pre-operative dialysis?
- Optimization, optimization, optimization!
- Dialysis should occur day of surgery or day before surgery
- Review dialysis flowsheet if available
- Amount of fluid “taken off”
- Pre and post dialysis weights compare with day of surgery weight
- Note POST dialysis chemistry! Serum K < 5.5 mEq/L
What should the potassium level be after dialysis?
Less than 5.5 mEq/L
What drugs are readily cleared by dialysis?
- Low molecular weight
- Water soluble
- Non-protein bound
When should most drugs be delivered in regards to dialysis?
After dialysis
What are some neurological problems that can result from renal failure?
- Uremic encephalopathy
- Autonomic neuropathy
- Peripheral neuropathy
What are the symptoms of uremic encephalopathy?
- Asterixis
- Myoclonus
- Lethargy
- Confusion
- Seizures
- Coma
CCLAMS
What are some neurological problems that can occur after dialysis?
- Disequilibrium syndrome-transient CNS disturbance after rapid decrease in ECF osmolality compared with ICF osmolality
- Dementia
What are some hematological changes expected with renal failure?
- Anemia
- Impaired platelets-decreased platelet factor 3 activity and decreased adhesiveness and aggregation
- Impaired WBC function
- Release of defective von Willebrand factor
What are some causes of anemia in renal failure?
- Decreased erythropoietin production
- Decreased RBC production & cell life span
- GI blood loss, hemodilution, bone marrow suppression
- Excess PTH replaces bone marrow with fibrous tissue
What are some ways renal patients compensate for anemia?
- Increased 2,3-DPG
- Metabolic acidosis which favors rightward shift
What precautions with regards to aseptic technique should be taken for renal patients?
- Infection is a common cause of death
- Care with ETT-prone to pulmonary infection
- IVs, line insertion
What are some cardiac changes seen in renal failure patients?
- Increased cardiac output (compensation for low O2 carrying capacity)
- HTN (Na retention, RAS activation)
- Left ventricular hypertrophy
- CHR with pulmonary edema
- Deposition of calcium in the conduction system and on the heart valves
- Arrhythmias due to electrolyte imbalances
- Uremic pericarditis- can be asymptomatic, chest pain, tamponade, usually secondary to inadequate dialysis
- Accelerated CAD and PVD
What can be used to assess fluid balance in renal patients?
- Body weight
- Orthostatic hypotension (BP)
- Tachycardia (HR)
- Atrial filling pressures
What pulmonary changes do you see in a patient with renal failure?
- Minute ventilation increased to compensate for metabolic acidosis
- Increase pulmonary extravascular water=interstitial edema=widened alveolar/arterial O2 gradient
- Butterfly wings on chest xray secondary to increased permeability of alveolar capillary membrane
What endocrine changes do you see in a patient with renal failure?
- Peripheral resistance to insulin = poor glucose tolerance
- Hyperparathyroidism = prone to fractures
- Abnormal lipid metabolism = accelerated atherosclerosis
- Kidneys do not degrade hormones and proteins normally = increased circulating PTH, insulin, glucagon, GH, LH, PL
What are some GI/liver changes you will see in the renal failure patient?
- 10-30% of patients will develop GI Hemorrhage
- Anorexia
- Nausea and Vomiting
- Hypersecretion of gastric acid + delayed gastric emptying (autonomic neuropathy)
- High incidence of Hep B and C in these pts (multiple transfusions, etc.)
- Ascites with dialysis
Why is drug metabolism altered in patients with renal failure?
- Anemia
- Decreased serum protein
- Electrolyte abnormalities
- Fluid retention
- Abnormal cell membrane activity
What drugs are contraindicated in patients with kidney failure
Drugs that are eliminated by the kidneys unchanged are contraindicated. Examples: -Gallamine -Phenobarbital -LMWH
How can you assess fluid status?
- Vital signs
- Mucus membranes
- Orthostatics
What blood tests would you want for a patient with renal failure?
- Chemistry panel
- BUN
- Cr
- Creatinine Clearance
- Urine specific gravity
- Urine osmolarity
What blood tests assess GFR?
- BUN (10-20 mg/dl)
- Cr (0.7-1.5 mg/dl)
- Creatinine Clearance (110-150 ml/min)
What blood tests assess renal tubular function?
- Urine specific gravity (1.003-1.03)
- Urine osmolarity (38-140 mOsm/L)
What BUN level is indicative of a decreased GFR?
> 50 mg/dl
Besides GFR what else does BUN depend on?
BUN also depends on the production of urea so it is not a sensitive index
What can be causes of abnormal BUN despite a normal GFR?
- High protein diet
- GI bleed
- Febrile illness
What is the most common cause of increased BUN?
CHF secondary to the reabsorption of BUN
How long of a lag time is there after a change in GFR before changes in creatinine are seen?
8-17 hours
What changes to GFR correspond to a 50% increase in plasma creatinine?
A 50% decrease.
What is the source of creatinine?
Skeletal muscle.
What is the most accurate test of creatinine clearance?
A 24 hour collection is most accurate but a 2 hour test can also be helpful.
What is the normal creatinine clearance?
100-120 ml/min