Exam 3 Renal Assessment Flashcards
1
Q
The kidneys sit retroperitoneal between _______ and _______.
Which kidney is slightly more caudal (lower) to accommodate the liver?
A
T12 and L3
Right
2
Q
What is the functional unit of the kidney?
A
Nephron
3
Q
The kidneys receive ______% (range) of CO.
A
20% to 25% (1- 1.25 L)
4
Q
Besides the kidneys, what organ is retroperitoneal?
A
Spleen
5
Q
Primary functions of the kidneys (6 functions).
A
- Maintain extracellular volume and composition
- Blood Pressure Regulation (Intermed/Long)
- Excretion of Toxins and Metabolites
- Maintain Acid-Base Balance
- Hormone Production (EPO)
- Blood glucose homeostasis
6
Q
The lungs and kidneys are the primary regulators of acid-base balance, where the lungs excrete __________ and the kidneys excrete the ___________.
A
Lungs excrete volatile acids (CO2)
Kidneys excrete non-volatile acids
7
Q
Inadequate oxygen delivery to the kidney causes it to release ________.
A
Erythropoietin
Things that can cause decreased O2 delivery: anemia, reduced intravascular volume, and hypoxia.
8
Q
What can reduce EPO production and lead to chronic anemia?
A
Severe kidney disease
9
Q
Calcium requires ________ for adequate absorption and utilization.
A
Calcitriol (Active Vitamin D)
10
Q
How does Vitamin D get activated?
A
Through the kidneys.
11
Q
What hormone will increase active Vitamin D levels?
A
PTH
Negative feedback loop
12
Q
For someone who is chronically anemic what can they take?
A
Synthetic EPO and Iron to generate more RBC
Long term dialysis patients will be on these medications, dialysis will negate the RBCs.
13
Q
____-% of body weight in non-obese patients is composed of water.
A
60%
14
Q
What are the two main fluid compartments?
A
ECF and ICF
15
Q
Per this lecture ECF is _______ the volume of ICF.
A
1/2
16
Q
What are the ways osmolality sensors in the anterior hypothalamus regulate fluid?
A
Stimulate thirst
Release Vasopressin (ADH)
17
Q
What is a normal sodium level?
A
135-145 mEq/L
18
Q
There are no absolute cut offs for sodium level for surgery, but these numbers will be a good reference.
Na level below _________ mEq/L and above _______ mEq/L are a no go for surgery.
A
Below 125 mEq/L
Above 155 mEq/L
19
Q
What are some causes of hyponatremia?
A
Prolonged sweating
Vomiting/diarrhea
Insufficient aldosterone secretion
Excessive intake of water
20
Q
What percent of people in the hospital have hyponatremia?
A
15%
21
Q
There are two patient populations where we are most concerned about sodium levels.
A
Neuro patients
Kids
22
Q
The most severe consequence of hyponatremia are these three things:
A
Seizures
Coma
Death
23
Q
What are treatments for hyponatremia?
A
Treat underlying causes
Normal Saline
Hypertonic 3% Saline (1 meq/L/hr)
Lasix
Mannitol
24
Q
Over half of the patients that had their sodium corrected faster than 6 mEq/L in 24 hours can cause __________ syndrome.
What could this result in?
A
osmotic demyelination
Seizures, coma, death
25
What is the dose and rate of 3% hypertonic saline for patients that are hyponatremic and seizing?
3-5 mL/kg of 3% saline
Give dose of over 15-30 minutes
26
Hyponatremic seizures are a medical emergency and can cause __________ brain damage.
Irreversible
27
What are the causes of hypernatremia?
Excessive evaporation
Insufficient ADH
Poor oral intake (very young, old)
Overcorrection of hyponatremia
Excessive sodium bicarb to tx acidosis
28
Be cautious when using sodium bicarb to treat acidosis, what is a good alternative to use if you want to avoid raising sodium?
Tromethamine injection **(THAM)** is indicated for the prevention and correction of metabolic acidosis.
29
Effects of hypernatremia
Orthostasis - syncope from standing up
Restlessness
Lethargy
Tremor
Muscle Twitching/ Spasticity
Seizures
Death
30
Treatments for hypernatremia?
First, assess volume status (tachycardic, hypotensive, u/o, skin turgor, CVP, SV variation)
Then treat the cause.
31
Treatments for the following.
Hypernatremic Hypovolemia:
Hypernatremic Hypervolemia:
Hypernatremic Euvolemic:
Hypernatremic Hypovolemia: normal saline
Hypernatremic Hypervolemia: diuretic
Hypernatremic Euvolemic: water replacement (PO or D5W)
32
What is normal potassium level?
3.5 to 5 mEq/L
33
Patients will not go to surgery if potassium is less than ______ or greater than _______ mEq/L.
K+ less than 3 mEq/L
K+ greater than 5 mEq/L
34
What are the causes of hypokalemia?
Excessive release of aldosterone
Diuretics drugs (*Lasix, hydrochlorothiazide*)
Kidney disease
Excessive intake of licorice (**kids eating too much licorice.**)
DKA (frequent urination)
35
Effects of hypokalemia.
**Generally, cardiac and neuromuscular (K+ of 2mEq/L)**
Dysrhythmias (K+ of 2mEq/L)
Muscle weakness
Cramps (Eat a banana)
Paralysis
Illeus (lose parastalsis)
36
What changes in EKG will you see with hypokalemia?
**U-waves**
*You will see this on the exams and boards.*
37
Treatments for hypokalemia
IV/PO Potassium
*May require days to correct.*
38
10 mEq of potassium will increase serum K+ by _____ mEq/L.
0.1 mEq/L
39
Why may PO potassium be faster in increasing serum potassium levels?
A larger dose can be given PO compared to 10-20 mEq/hr with IV.
40
When replacing potassium levels, what other electrolytes do you need to keep an eye on?
Phosphorus (normal levels 2.5 - 4.5 mg/dL)
41
Who are at the most risk of dysrhythmias when getting potassium replacement?
CHF patients
Digoxin patients
42
What are the causes of hyperkalemia?
Renal disease (long-term dialysis pt, fistula)
Insufficient secretion of aldosterone
Acidosis
Tissue/muscle damage
Use of depolarizing NMBD (Sch)
Hypoventilation
43
With hypoventilation, a pH decrease of 0.1 will cause a ______(range) increase in potassium.
0.4 to 1.5 mEq/L increase in potassium
44
What are the effects of hyperkalemia?
Potentially asymptomatic
GI upset
Malaise
Skeletal muscle paralysis
Severe cardiac dysrhythmias (cardiac arrest)
Lowers resting membrane potential
Decreases action potential duration
45
What are EKG presentations of hyperkalemia?
Peaked T-waves (can progress into sine waves if hyperkalemia is severe)
46
Treatment of hyperkalemia
Bicarbonate
Glucose
Insulin (10U and 25g of D50)
Calcium (stabilize cell membrane)
Increase RR
Albuterol
Dialysis
47
What do CRNAs do that can cause hyperkalemia in a patient?
Massive Transfusion Protocol and Blood Products
48
What are lab tests for renal function?
**GFR (best measurement)** 125-140 ml/min- great for trends but not for acute states.
**Creatinine Clearance (best for acute state)**
**Serum Creatinine** 0.6-1.2mg/dL - estimate of GFR
49
What is creatinine?
A substance produced by skeletal muscle and is a byproduct of creatine breakdown.
50
Creatinine production is constant and directly __________ to muscle mass.
proportional
*A emaciated individual will probably have a lower creatinine level compared to a bodybuilder. But if you see that a cachectic person has a high creatinine level, it might be a sign that the kidneys are not working well.*
51
Creatinine undergoes renal _________ but not _________, making it a useful indicator of GFR.
Creatinine undergoes renal **filtration** but not **reabsorption**, making it a useful indicator of GFR.
52
100% increase in creatinine indicates a ____% reduction in GFR.
50%
*If creatinine goes from 1.2 to 2.4, GFR will decrease by 50%.*
53
Large amounts of protein in the urine may suggest ________ injury.
Labs values and test.
Glomerular Injury
(*High levels of protein can also mean UTI and not glomerular injury.*)
>750 mg/day of urine protein or 3+ on dipstick
54
What are normal BUN ranges?
8-20 mg/dL
*BUN can be misleading. Diet and changes in intravascular volume can increase or decrease BUN.*
55
What does specific gravity compare?
What are normal ranges of specific gravity?
Comparing 1 mL of urine to 1 mL of distilled water. Measures the ability of the kidney to concentrate or dilute urine.
1.001-1.035
56
What is BUN: Creatinine ratio?
10: 1
57
________ is the primary metabolite of protein metabolism in the liver.
Urea
58
Because urea undergoes filtration and reabsorption, **BUN** is a better indicator of ____________ symptoms than as a measure of GFR.
Uremic symptoms
59
What causes BUN of <8 mg/dL?
Overhydration, too much hydration, dilution.
Decrease Urea production (malnutrition, liver dz)
*EtOH patients will forget to eat and get calories just from the booze.*
60
What causes a BUN of 20-40 mg/dL?
Dehydration
Increase Protein Input (high protein, GIB, Hematoma breakdown)
Catabolism (Trauma, Sepsis)
Decrease GFR
61
What causes a BUN >50 mg/dL?
Decrease GFR
62
Which lab test is a good evaluation of fluid hydration status?
BUN: Creatinine Ratio
*BUN can undergo filtration and reabsorption. Creatinine only undergoes filtration. Because of this reason, the ratio between these substances in the blood is helpful in evaluating hydration status.*
63
A BUN:Cr ratio greater than _________ indicates prerenal azotemia.
20:1
64
A medical condition characterized by abnormally high levels of nitrogen-containing compounds (such as urea, creatinine, and various body waste compounds) in the blood. It is largely related to insufficient or dysfunctional filtering of blood by the kidneys.
Azotemia
65
Oliguria definition.
Polyuria definition.
Annuria definition.
Oliguria is decreased u/o (**500 mL in 24 hours**).
Polyuria is excessive u/o.
Annuriaa is no u/o.
66
What are the factors that can lead to a false urine specific gravity (SG)?
Look at the big picture and assess the weight of the urine relative to sterile water. SG measures the ability of the kidney to concentrate or dilute urine.
Advanced age
Contrast dye
Abx
Diuretics
Mannitol
Glucose
Proteins
67
What does a high urine specific gravity indicate?
What does a low urine specific gravity indicate?
More concentrated urine, more solutes.
Less concentrated urine, less solutes.
68
What number indicates good urine output from an anesthesia standpoint?
30 mL/hr (no standardization for weight and no clinical picture)
**0.5-1 mL/kg/hr is more accurate**
69
The normal values for total U/O range between _________and _______ mL in adults with normal fluid intake of 2L during 24 hours.
800 to 2000 mL
70
What is an early indicator of volume change (arm just got cut off)?
ABG results will quickly indicate volume change.
-Base Excess or Base Deficits will indicate volume loss (Indicator of acid/base balance in the blood).
-Increase in Lactate
*H/H will not show the volume loss as quickly.*
71
_________ mL in 24 hours will be called oliguria.
500 mL
72
CVP trending below _______ mmHg (range) will be volume responsive.
CVP above ________ mmHg (range) will be considered volume overloaded.
5 to 8 mmHg
15 to 20 mmHg
*CVP is equivalent to right atrial pressure*
73
_______ is a powerful stimulus for renal vasoconstriction.
Left atrial pressure (wedge pressure)
*Increase LAP, increase vasoconstriction. Afferent arteriole will increase to decrease hydrostatic pressure.*
74
What are the criteria for using stroke volume variation in assessing fluid status?
Assume the patient is on positive-pressure ventilation.
Assume the patient is in NSR.
Compare inspiratory and expiratory pressure to assess SVV.
75
An IVC greater than _______% collapse indicates a fluid deficit.
50%
To assess, place an ultrasound on IVC and perform a passive leg raise, if the quick change in volume dilates IVC, the patient may be in a fluid volume deficit.
76
What is acute renal failure?
Deterioration of renal function over hours to days.
Accumulation of nitrogenous waste products over a short period of time. Difficulty maintaining fluid/electrolyte homeostasis.
77
If someone with AKI progress to dialysis and MSOF, mortality is now greater than ________.
50% (due to sepsis, CV dysfunction, pulmonary compilations)
78
What do CRNAs do that causes AKI?
Letting the patient get hypotensive.
79
What do providers do that can cause AKI?
Contrast
*Minimize contrast load, and mitigate with fluids.*
80
What are the risk factors for AKI?
**Pre-existing renal disease**
**Advanced age**
**Congestive HF**
PVD
DM
Sepsis
Jaundice
Emergency Surgery
Major Operative Procedures (Cross-Clamped)
81
Diagnosing AKI:
Serum creatinine rise > ______ mg/dL
_______% decrease creatinine clearance
Serum creatinine change by _______ mg/dL within 48 hours.
Diagnosing AKI:
Serum creatinine rise **>0.5 mg/dL**
**50%** decrease creatinine clearance
Serum creatinine change by **0.3 mg/dL** within 48 hours.
82
Symptoms of AKI
Malaise
Fluid Overloaded
Hypotension
83
What are the types of AKI?
Pre-renal
Renal
Post-renal
84
What are the causes of prerenal azotemia (ARF)?
Hemorrhage
GI fluid loss
Trauma
Surgery
Burns
Cardiogenic shock
Sepsis
Aortic clamping
Thromboembolism
Aortic aneurysm dissection
**All these will decrease blood flow to the kidneys**
85
What are the causes of renal azotemia (ARF)?
Acute glomerulonephritis
Vasculitis
Interstitial nephritis
ATN
Contrast dye
Nephrotoxic drugs
Myoglobinuria
**Real kidney problems. Think infections and inflammation.**
86
What are the causes of postrenal azotemia (ARF)?
**Nephrolithiasis (kidney stones, most common cause)**
BPH
Clot retention
Bladder carcinoma
UTI- cellular debris
Trauma to the urinary tract
**Think mechanical obstruction post-kidney.**
87
Pre-renal azotemia makes up _________ of hospitalized acquired cases.
If pre-renal azotemia is not treated in time, it will progress to _____.
Half (*Fortunately, this is rapidly reversible.*)
ATN
88
How can you distinguish a pre-renal from an intra-renal AKI?
Pre-renal can reabsorb sodium and water.
*Obtain urine/serum test prior to dopamine, mannitol, diuretics, fluids.*
89
Treatment of pre-renal azotemia.
Treat through the restoration of renal blood flow.
*Usually, a fluid bolus will be enough to reverse pre-renal azotemia.*
90
Compare diagnostic findings between prerenal oliguria and ATN.
BUN: Cr ratio will be normal in ATN and 20:1 in Pre-renal.
Pre-renal urine will be clear. ATN will have more sediments.
91
What are the causes of renal azotemia?
Reperfusion injury
Release of cytokines, free radicals, and inflammatory cells
Blockage/obstruction inside the kidney
92
What will be the BUN: Cr ratio of renal azotemia?
What happens to GFR?
What happens to Urea?
What happens to Creatinine?
Less than 15
GFR will decrease, and nothing will get filtered
Urea does not get reabsorbed; low urea in the blood, high urea in the urine.
Creatinine filtration decreases, leading to higher Cr in the blood.
93
Neurological complications of AKI.
Uremic Encephalopathy (d/t protein and amino acids in the blood).
*Improve with dialysis*
94
List the order of incidence from compilations of CKD:
Pulmonary Edema, LVH, CHF, Systemic HTN
Order of incidence:
1. Systemic HTN
2. LVH
3. CHF
4. Pulmonary Edema
95
Hematological complications of AKI.
Anemia - d/t decreased RBC production, RBC survival, EPO production, hemodilution
Platelet dysfunction (uremic bleeding) - treat with DDAVP
96
Metabolic complications of AKI.
**Hyperkalemia**
Water and Sodium retention
Hypoalbuminemia - responds slower to medication
Metabolic Acidosis
97
Anesthesia concerns of AKI.
**Correct fluid, electrolytes, acid/base status**
Maintain MAP
Vasopressors-(consider carefully, and think about where the receptors work).
Prophylactic sodium bicarb - decreases the formation of free radicals and treats academia.
Invasive hemodynamic monitoring and lots of ABGs
Pre-Op dialysis, lower K+ (BZD and opioids might stick around longer in patients until they have dialysis).
98
Unlike AKI, CKD is progressive and __________.
What is the leading cause of CKD?
Irreversible
**DM and HTN**
99
RIFLE Criteria
100
Describe stages of ESRD and GFR for each stage.
*No U/O with stage 4 or 5*
*Stages 3,4,5 - dialysis-dependent*
101
On average, GFR decreases by ______ per decade starting from age 20.
10
102
CV effects of CKD.
Systemic HTN (cause and consequence)
Retention of sodium and water
Activation of RAAS d/t decreased GFR
Dyslipidemia (Triglycerides >500, LDL >100)
Silent MI (most prevalent in DM and women)
103
What are the functions of ACE inhibitors and ARBs?
Why do we want to hold these medications on the day of surgery?
Decrease systemic and glomerular hypertension
Decrease proteinuria
Decrease glomerulosclerosis
Hold ACE inhibitors/ARBs on the day of surgery to reduce the risk of intraoperative hypotension.
104
What are the hematological complications of CKD?
Anemia - responds well to EPO, target >10 Hgb
105
What are the five indications of dialysis?
1. Volume overload
2. Hyperkalemia
3. Severe Metabolic Acidosis
4. Symptomatic Uremia
5. Medication Overdose
106
Considerations of dialysis:
HD is more ______ than PD.
PD is more gradual and favored for patients that can't tolerate __________ associated with HD (CHF/unstable angina).
__________ is the most common adverse event.
_________ is the leading cause of death in dialysis patients.
HD is more **effective** than PD.
PD is more gradual and favored for patients that can't tolerate **fluid shifts** associated with HD (CHF/unstable angina).
**Hypotension** is the most common adverse event.
**Infection** is the leading cause of death in dialysis patients.
107
The risk of pre-renal azotemia is reduced by maintaining a MAP greater than _______ mmHg and providing appropriate hydration.
>65 mmHg
108
No clear benefit to crystalloids vs. colloids, but _______ are clearly associated with an increased risk of renal injury.
Hydroxyethyl starches (synthetics)
109
Excessive use of 0.9% NaCl leads to ________.
Hyperchloremic Metabolic Acidosis
110
In healthy patients, what does alpha-1 agonist do to renal blood flow?
Reduce RBF
*Septic renal patients will benefit from alpha-1 agonists for MAP support. Increased renal perfusion outweighs the renal vasoconstrictive effects.*
111
Vasopressin preferentially constricts the __________ arteriole. Maintains GFR and UOP better than NE or Neo.
efferent
112
Renal dose __________ does NOT prevent or treat AKI.
dopamine
113
Anesthesia concerns of CKD.
Assess the stability of ESRD.
Get the accurate weight of the patient within 24 hrs of surgery.
Well-controlled BP
Glucose management (A1c).
Aspiration Precaution (increase risk)
Uremic bleeding (dysfunctional platelets)
114
What are treatments of uremic bleeding?
Max effect time:
Duration:
**DDAVP - max effect 2-4 hours, last 6-8 hours, give this in pre-op**
Cryo (Factor VIII, vWF)
115
What neuromuscular blockers are not dependent on the kidneys?
Atracurium
Cisatracurium
*Hoffman elimination- plasma esterases affected by pH and temperature.*
116
When taking care of renal patients, what medications do we worry about having active metabolite?
Opioids (morphine, meperidine)
*Morphine is cleared through the urine, active morphine metabolite will lead to respiratory depression.*
117
Lipid insoluble drugs will have a _________ duration of action in renal patients.
prolonged duration (Thiazides, loop diuretics, digoxin, Abx)
*Consider decreasing the dose base off of GFR*
118
What induction medications are excreted by the kidneys?
Phenobarbital
Thiopental
119
What muscle relaxants are excreted by the kidneys?
Pancuronium
Vecuronium
*If kidneys do not excrete them, the liver will.*
120
What cholinesterase inhibitors are excreted by the kidneys?
Edrophonium
Neostigmine
121
What CV drugs are excreted by the kidneys?
Atropine
Digoxin
Glycopyrrolate
Hydralazine
Milrinone
122
What antimicrobials are excreted by the kidneys?
**Vancomycin**
Aminoglycosides
Cephalosporins
PCN
123
What is the main adverse effect of Demerol?
Demerol has active analgesic and CNS effect.
**The main adverse effect is neurotoxicity.**
124
Patients maintained on dialysis should undergo dialysis _______ hours preceding elective surgery.
24 hours
125
What is TURP?
When is it indicated?
Transurethral Resection of the Prostate.
TURP is indicated for prostate removal in BPH.
126
Neuraxial anesthesia is common in TURP procedures. The spinal is up to a ______ level.
T10 level
This will allow earlier detection of complications because you can assess the patient's mentation throughout the procedure.
127
What are the irrigation fluids used in TURP procedures? List the Pros and Cons of each fluid.
128
TURP requires continuous irrigation to facilitate visualization. The fluid is absorbed through the open venous sinuses of the prostate. Estimated absorption volume: __________ ml/min.
30 ml/min
*Risk for fluid overload and toxicity. TURP syndrome.*
129
The pressure of infusion is influenced by the height of the irrigation solution. The height should be no more than __________ cm above the patient.
60 cm
130
Cardiopulmonary Sx of TURP.
CNS Sx
Metabolic Sx
Misc Sx
131
Treating TURP syndrome.
Stop the case
Na+ > 120 mEq/L, fluid restriction and lasix
Na+ < 120 mEq/L give 3% at 100 mL/hr, d/c when Na+ >120 mEq/L.
132
Complications of TURP
Bladder Perforation
Bleeding
Hypothermia
133
What are the three types of Urolithiasis?
Nephrolithiasis - Renal Stone
Ureterolithiasis - Ureter Stone
Cystolithiasis - Bladder Stone
134
What do patients with kidney stones present with?
Intermittent or continuous moderate to severe colicky pain in the ipsilateral flank and upper abdomen
135
Treatment for kidney stones.
Conservative nonsurgical therapy for smaller stones consists of analgesics (NSAIDS, opioids)
Aggressive fluid administration to promote urine flow and passage of the stone
Medical expulsive therapy (MET)- promotes ureter relaxation and spontaneous passage of small ureteral stones.
ESWL, PCNL, Laser Lithotripsy
136
What is ESWL?
Absolute contraindications for this procedure?
Extracorporeal Shock Wave Lithotripsy - a machine that will direct energy to the stone.
Pregnancy and high risk of bleeding.
137
The shock wave of ESWL is timed to the R-wave to reduce the risk of __________.
R on T Phenomenon
*Other risks include tissue and internal organ trauma.*
138
What is a PCNL?
Percutaneous Nephrolithotomy.
Place urethral stents and then a nephrostomy tube to access the stone.
139
Paraplegic patients with a sensory deficit below ______ are at risk for autonomic hyperreflexia and require anesthesia to block afferent stimulation that can provoke this reaction (bladder distention).
Below T6
140
Patients with a spinal corder injury at _______ or higher are at risk for autonomic hyperreflexia.
T7 or higher
*Vascular instability, initially a substantial increase BP above the level of the lesion, followed by overzealous vagal response, with bradycardia, heart block, vasodilation, and flushing*
141
Patients with idiopathic hypercalciuria, treated with _______-
thiazide diuretics
142
_______ prophylaxis is important, particularly with infected stones or pyelonephritis.
Abx
143
When lasers are required, appropriate _______ protection for the perioperative team and patient.
eye
144
Combined blood flow through both kidneys accounts for ______ of total cardiac output.
20-25%
145
Angiotensin, NE, and ______ influence renal arterial tone.
Epinephrine
146
The primary source of urea is in the ________.
Liver
147
Normal serum creatinine concentration for males.
Normal serum creatinine concentration for females
Males: 0.8-1.3 mg/dL
Females: 0.6 - 1.0 mg/dL
148
Normal creatinine clearance (range): _________
110-150 mL/min
149
Creatinine clearance measurements for mild renal impairment (range) __________
40-60 mL/min
150
Creatinine clearance measurements for moderate renal impairment (range) __________
25-40 mL/min
151
These drugs undergo hepatic metabolism and conjugation prior to elimination in the urine (Select all that apply).
A. Pavulon
B. Benzos
C. Opioids
D. Anectine
A, B, and C
Anectine (Sch) is metabolized by plasma cholinesterase
152
What is the ideal anesthetic agent for renal patients?
Forane (Isoflurane)
153
Which kidney is lower?
The right kidney is slightly lower than the left kidney.
154
What are the three layers of the kidney?
Renal capsule
Renal fascia
Adipose capsule
155
Acceptable urine output in the OR is _____ mL/kg/hr unless the patient is on bypass, then it is ______ml/kg/hr.
0.5 mL/kg/hr (OR)
1 mL/kg/hr (bypass)
156
Renin is secreted by the _______.
Juxtaglomerular Apparatus
