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Flashcards in Renal/Heme Deck (90):
1

The dominant form of PKD is also associated with

intracranial aneurysms and mitral valve prolapse

2

___% of ESRD patients have DM

50%

3

___% of ESRD patients have HTN

25%

4

Patients going for surgery with ARF will always have an ASA designation of

E

5

Two types of dialysis

Intermittent hemodialysis
Continuous peritoneal dialysis

6

Wide spread systemic manifestations are seen from uremia when the GFR decreases below

25mL/min

7

Patients with a GFR < ____ rely on dialysis for survival

10mL/min

8

Continuous peritoneal dialysis involves _____ and may be better for those who _______

1) Diffusive solute transport across the peritoneal membrane

2) Those who do not tolerate rapid fluid shifts and those with poor vascular access

9

Dialysis is required in these conditions

Oliguria
Fluid overload
Hyperkalemia (can cause fatal arrhythmia)
Severe acidosis (will inhibit proper enzyme activity)
Metabolic encephalopathy
Pericarditis (will help reduce the fluid around the heart)0
Coagulopathy
Refractory GI symptoms
Drug toxicity

10

An AV fistula involves the anastamosis of

The radial artery and cephalic vein

11

Emergency vascular access for dialysis can be obtained from

Femoral vein or internal jugular vein

12

Basic purpose of hemodialysis

Diffusion of solutes between the blood and the dialysis solution remove metabolic wastes and restore buffers to the blood

13

A weight gain of __-__% of body mass in 2 days is appropriate between dialysis treatments

3-4%

14

These types of drugs are readily cleared by dialysis

Low-molecular weight, water soluble, non protein bound drugs

(Best to give scheduled drugs after dialysis)

15

S/S of uremic encephalopathy

Asterixis
Myoclonus
Lethargy
Confusion
Seizures
Coma

16

What is disequilibrium syndrome?

Transient CNS disturbance after rapid decrease in ECF osmolality compared with ICF osmolality --> this is due to dialysis

17

Patients with a GFR < __ will generally have anemia

30
(Unless the patient is on aggressive EPO replacement therapy. Most ESRD patients will be on EPO to increase their hematocrit to 36-40%)

18

Why do ESRD patients usually tolerate their anemia well

Because they have acidosis and increased 2,3-DPG, both of which shift the hgb-oxygen disassociation curve to the right (facilitates the unloading of O2)

19

Why are most patients with ESRD anemic?

1) Decreased EPO (decreases RBC production)
2) Decreased RBC life-span
3) GI blood loss, hemodilution, bone marrow suppression
4) Excess PTH replaces bone marrow with fibrous tissue

20

When should you transfuse for someone with ESRD?

Transfuse only when absolutely indicated <6-7g/dL or significant intra-operative blood loss

21

What is an important cause of coagulation issues in someone with ESRD?

release of defective von Willebrand factor

22

What is autonomic neuropathy?

Autonomic neuropathy is a nerve disorder that affects involuntary body functions, including heart rate, blood pressure, perspiration and digestion.

It isn't a specific disease. Autonomic neuropathy refers to damage to the autonomic nerves. This damage disrupts signals between the brain and portions of the autonomic nervous system, such as the heart, blood vessels and sweat glands. This can cause decreased or abnormal performance of one or more involuntary body functions.

Autonomic neuropathy can be a complication of a number of diseases and conditions. And some medications can cause autonomic neuropathy as a side effect. Signs, symptoms and treatment of autonomic neuropathy vary depending on the cause, and on which nerves are affected.


May have dizziness and fainting, urinary problems, sexual difficulties, gastroparesis, sluggish pupils, or exercise intolerance.

23

Avoidance of high protein foods can be a subtle sign of

renal disease (contributing to azotemia)

24

Can an AV fistula revision be given class E status?

Yes, because E is necessary to save LIFE OR LIMB

25

Someone who can't tolerate large fluid shifts is more likely to be on (HD/peritoneal dialysis)

Continuous peritoneal dialysis

26

If someone's ESRD is progressing towards dialysis, we should place IVs on their (dominant/non-dominant arm)

Dominant, because if they have an AV fistula placed, this will be on their non-dominant.

27

When should someone have dialysis before surgery?

The day before or the morning of

28

Considerations for the patient who JUST had HD

May have low K+ (but remember, that their body is still equilibrating)
May be dry--BP can plummet

29

Neuro considerations in the renal patient

1) Peripheral neuropathies
2) Autonomic neuropathy
3) Uremic encephalopathy
- Asterixis
- Myoclonus
- Lethargy
- Confusion
- Seizures
- Coma
4) Demential

30

Questions to ask renal patients for neuro

Ever feel confused? Slow thinking? Foggy?
Ever have seizures?
Numbness/tingling in your extremities?
Dizziness when you stand up? (ANS neuopathy)
Any involuntary movement? Shaking, etc.

31

Why do people in ESRD get anemia?

Low EPO
- Low production
Decreased RBC lifespan
GI bleeds
Fluid overload (dilutional)
Excess PTH in circulation
- Bone marrow replaced with fibrous tissue

32

Why do most people in ESRD tolerate anemia well?

Acidosis and increased 2,3-DPG encourage off-loading.

However, person will not tolerate the anemia well if they also have CAD

33

Mortality rate for those on dialysis, and what do they die from?

25% die per year
1/2 from infection (use aseptic technique!!!!)
1/2 from CV disease

34

Are those with ESRD more or less likely to bleed?

More likely
- Impaired platelets (decreased plt factor III activity -> less adhesiveness and aggregation)
- defective vWF
- Dialysis causes hypocomplementemia

35

Affect of ESRD on CO

Increases it (d/t anemia)

36

Hypercalcemia in ESRD causes

Conduction abnormalities
Deposition on heart valves
Kidney stones

37

People with inadequate dialysis can get this type of pericarditis

Uremic pericarditis

Can be asymptomatic, or cause:
- Chest pain
- Tamponade

38

Are those with ESRD going to be fluid overloaded or dry?

Either.
Generally overloaded, but could be dry after HD

39

Effect of ESRD on the pulm system

1) Increased MV (to compensate for acidosis)
2) Pulm edema from fluid overload --> increased A-a gradient
3) Increased permeability of alveolar/capillary membrane (shows as butterfly wings on CXR)

40

Effect of ESRD on the endocrine system

1) Insulin resistance
2) Accumulation of PTH, insulin, glucagon, GH, LH, PL because we are not clearing them
3) Hyperparathyroidism

41

Why do people with ESRD have accelerated atherosclerosis

LDL isn't cleared effectively

42

___-__ of ESRD patients will develop GI hemorrhage

10-30%
This can be fatal

43

Effect of ESRD on the GI system

1) Hypersecretion of acid and delayed gastric emptying (autonomic neuropathy)--> GERD
2) N/V
3) GI hemorrhage
4) Incidence of Hep B&C d/t transfusions for amemia
5) Ascites from dialysis

44

Why do patients with ESRD have altered drug effects?

Anemia
Low serum protein
Electrolyte abnormalities
Abnormal cell membrane activity
Leaky BBB
Less renal elimination

45

These drugs are eliminated unchanged by the kidneys, and are contraindicated in ESRD

LMWH
Phenobarbital
Gallamine

46

Why is LMWH such a problem in those with ESRD?

Because it's excreted unchanged in the kidneys and not removed well by dialysis.
Will result in major bleeding problems.

47

Do we want to replace K+ if the level is below 3.5?

NOPE! If it is low, it's probably because the pt just had HD. Give it time to equilibrate.

48

___% of nephrons have to be lost before we see a change in GFR

50%

49

A BUN > _____ is indicative of a decrease in GFR in patients with normal diets

50

50

Why might BUN be elevated in the absence of renal disease?

High protein diet
GI bleed
Fever

51

What is the most common cause of high BUN?

CHF secondary to the reabsorption of BUN

52

Creatinine levels won't increase until __-__ hours after a decrease in GFR

8-17 hours

53

As the elderly age and thusly lose nephrons, why aren't their Cr levels elevated?

Less muscle mass.

54

Creatinine clearance test

24 hour collection (approximates GFR)
100-120 = normal
60-100 = decreased renal reserve
40-60 = mild impairment
25-40 = moderate insufficiency
<10 = ESRD

55

We will see these electrolyte abnormalities in renal failure

1)Hyponatremia (dilutional)
2) Hyperkalemia
3) Acidosis with anion gap
4) Hypermagnesemia (affects muscles & relaxant choice)
5) Hypocalcemia (unclear why)
6) Hypoalbuminemia (esp with dialysis)
7) Hyperglycemia (insulin resistance)

56

At what point should we start worrying about K+ levels in ESRD?

Think about treating once it reaches 6-6.5.
Remember they are better at tolerating high K+ levels

57

Treatment for hyperkalemia (K+>6.5)

Calcium gluconate 10% (10-20mL)**** fastest - antagonizes the effects of K+ on heart muscle
Sodium bicarb (50-100mEq IV)--> moves K+ into the cell
Glucose (50mL of D50) + regular insulin (10 units)--> shifts K+ into the cells
Dialysis
Ion exchange resin

58

We want to avoid giving calcium gluconate to correct hyperkalemia if

the pt is receiving dig therapy

59

Are we concerned about bleeding if plt count is fine?

YES! Plts are present, but not functioning properly

60

When would we transfuse a pt in renal failure?

When absolutely indicated
- <6-7 g/dL
- significant intra-op blood loss

61

Prothrombin time

10-12 seconds
Factors: 1, 2, 5, 7, 10

62

INR

.8-1.2
Factors: 1, 2, 5, 7, 10 (same as PT)

63

PTT (plasma thromboplastin time)

25-35 sec
Factors, 1, 2, 5, 8, 9, 10, 11, 12

64

Activated clotting time

90-120 sec
Factors 1, 2, 5, 8, 9, 10, 11, 12 (same as PT)

65

Thrombin time

9-11 sec
Factors: 1 & 2

66

Fibrinogen

160-350
Factor 1

67

This test is the best screening measure to test for coagulation in ESRD

Bleeding time-- tells you plt function

68

How to reverse bleeding problems in ESRD

Desmopressin (.3-.4 mg/kg over 30min)
- increases release of vWF
Cryoprecipitate (10 units over 30 min)

Have blood ready to go
- T&C and blood warmer set up

69

Equation for calculating arterial oxygen content

FiO2(Hgb x 1.30) + (PaO2 x .003)

70

Goals if the patient is anemic

Keep CO2 high normal (acidotic side will favor release of O2 in tissues)
Keep the patient warm

71

Compensation for chronic anemia

Increase in CO
Decrease in SVR
Increase in plasma volume
Increase in 2,3-DPG
Increased extraction ratio in vascular beds
Redistribution of flow to organs with higher extraction ratios (heart, brain, and lungs)

72

Things to think about when deciding if we should transfuse

Is the anemia acute or chronic?
What caused the anemia?
What is their fluid status?
How urgent is the surgery?
What is the anticipated blood loss of the surgery?
Do they have co-existing disease that we don't want to reduce O2 in? (CAD, PVD, cerebrovascular disease, lung disease)

73

Will Hgb and Hct immediately reflect blood loss?

No, it takes about 3 days to reach a new plateau level

74

Trauma patient comes in with blood loss and hypotension. Should we manage with pressors or give blood?

Give blood! The patient is symptomatic. Also, giving pressors could make the condition worse by increasing O2 demand on the heart, but keeping O2 supply low.

75

Previous splenectomy may increase risk of post-op

infection

76

In hemolytic anemia, EPO is prescribed for ___ days pre-op

3

77

In hemolytic anemia, acute drops below ___ and chronic levels below ___ should be considered for transfusion

8
6

78

Questions for someone with sickle cell disease

These people have 30% incidence of having complications. Complications include
- Stroke
- HF
- Pulm HTN
- MI
- Hepatic or splenic sequestration
- Renal failure

So ask to see if they've ever experienced any of these complications? Frequency and severity of occlusive crisis, etc?

79

Pre-op considerations for sickle cell disease

Questions
Transfuse if emergency surgery or no meetin 10/30.
Hydrate for 12 hours prior to surgery
Be wary of pre-op meds (decreased O2, and hypoventilationg causing acidosis can both result in sickling)
May be difficult to get IV access

80

How do we prevent a sickle crisis??

Avoid anything leading to
1) Hypoxemia
2) Hypovolemia
3) Acidosis
4) Stasis (positioning)
5) Cold

81

Complications of iron loading from chronic transfusions in thalassemia

DM
Adrenal insufficiency (will have less response to pressors)
Liver dysfunction & coag abnormalities
Hypothyroidism and hypoparathyroidism
Arrhythmias (get EKG)
Heart failure (get ECHO)

82

How does thalassemia affect the airway

The compensatory increase in RBC production expands marrow, causing bones to expand, causing craniofacial deformities and overgrowth of the maxillae --> causing trouble with DVL

83

Things to consider with aplastic anemia

All 3 cell types are low--> think about implications
Often d/t autoimmune -> may be on steroids (need stress dose)

84

Aplastic anemia and induction

Avoid nasal intubation (bleeding)
Labile hemodynamic responses to induction
Regional anesthesia may or may not be OK - check coags

85

Porphyria

Caused by lack of enzyme in production of heme (which is a porphyrin), causing a build-up of precursors. Avoid meds that stimulate the RBC production pathway. Ask them what brings on their attacks like drugs and foods

86

S/S of porphyria attack

Electrolyte disturbances
Life threatening muscle weakness (required intubation)
CNS disturbances
ANS instability
Severe abd pain

87

Meds that are unsafe in porphyria

Barbiturates***** (NO THIOPENTAL)
Phenytoin
Alcohol
Diazepam
Sulfonamide antibiotics
Etomidate????
Nifedipine (probs avoid)
Ketorolac (Probs avoid)

88

What should we do if we have a patient with a hereditary bleeding disorder?

Get a hematologist consult

89

If your patient has DM or atherosclerosis, use this ratio to guide transfusion therapy

10/30

90

How to prevent renal toxicity if your patient is on Cisplatin

Give fluids and mannitol