urologic surgery Flashcards
1
Q
a testicular torsion is an
A
emergency
2
Q
the kidneys receive how much cardiac output
A
20-25%
3
Q
the nephron is made up of the
A
outer cortex and inner medulla
4
Q
the nephron maintains homeostasis via
A
filtration, reabsorption and tubular excretion
5
Q
normal GFR
A
125 mL/min
6
Q
the outer cortex contains the
A
glomerulus
7
Q
what shouldn’t you see in the urine?
A
glucose and protein
8
Q
dilation of afferent arteriole ___ GFR
A
increases
9
Q
constriction of afferent arteriole ____ GFR
A
decreases
10
Q
what is the strongest trigger in releasing aldosterone to reabsorb sodium and water
A
K+
11
Q
filtration is the 1st process in
A
making urine
12
Q
the renal vasculature is richly innervated by
A
SNS
13
Q
renal hormones
A
aldosterone, antidiuretic hormone, angiotensin, atrial naturetic factor, vitamin D, prostaglandins
14
Q
filtration happens in the
A
bowman’s capsule
15
Q
what is filtered in the bowman’s capsule
A
water, glucose, electrolytes, amino acids, urea, creatinine
16
Q
where does reabsorption occur
A
proximal and distal tubules
17
Q
what is reabsorbed in the proximal tubule
A
glucose, k+, urate, HCO3
18
Q
what is reabsorbed in the distal tubule
A
Na+ and H2O
19
Q
anesthetic drug effects on renal function
A
depresses normal renal function
renal blood flow decreases by 30-40%
impairs autoregulation
20
Q
general anesthesia is associated with a decrease in
A
renal blood flow
GFR
urinary flow
electrolyte secretion
21
Q
ALL of the volatile anesthestics cause ____ in renal vascular resistance
A
a mild increase d/t compensatory mechanism in response to decreases in CO and SVR
22
Q
What can attenuate reductions in renal blood flow and GFR?
A
preop hydration
decreased concentrations of volatile anesthetics
maintenance of blood pressure
23
Q
Sevoflurane can cause ____ but NOT ____
A
high fluoride ion levels but NOT nephrotoxicity d/t rapid metabolism
24
Q
When Sevoflurane is degraded by absorbents is produces
A
compound A or vinyl ether
25
how do you decrease risk of compound A nephrotoxicity with someone receiving sevoflurane?
high gas flows (1L/min FGF for 2 MAC hours max)
decrease gas concentration
use of carbon dioxide absorbents
26
at 1 L/min of FGF Sevoflurane 2% =
2 MAC hours
27
at 1 L/min of FGF Sevoflurane 1% =
4 MAC hours
28
at 1 L/min of FGF Sevoflurane 4% =
1 MAC hour
29
Fluoride ion toxicity
fluoride interferes with active transport of sodium and chloride in the loop of Henle
30
Fluoride is a ___ vaso___
potent vasoconstrictor
31
nephrotoxicity from fluoride ions causes
proximal tubular swelling and necrosis
32
signs and symptoms of fluoride nephrotoxicity
```
polyuria
hypernatremia
serum hyperosmolality
elevated BUN/creat
decreased creatinine clearance
```
33
nephrotoxicity is related to
dosage, duration, and peak fluoride concentrations
34
Fluoride can inhibit
many enzyme systems including ADH
35
Acute kidney injury
renal functional or structural abnormality that occurs within 48 hours
increased creatinine 0.3 mg/dL or 50% increase
UO <0.5 mL/kg/hr x 6 hours
36
risk of AKI is increased by
hypovolemia, electrolyte imbalance, and contrast dye
37
pre-renal AKI causes
hypoperfusion without parenchymal damage from hemorrhage, vomiting, diarrhea, diuretics, sepsis, shock, CHF, norepi, NSAIDs, ACEi
38
Intrinsic AKI causes
result of damage to renal tissue from hypoperfusion, myoglobin, chemotherapy, infections, lymphoma, toxemia of pregnancy, vasculitis
39
postrenal AKI causes
due to urinary tract obstruction from renal calculi, peritoneal mass, prostate/bladder urethra tumor, fibrosis, hematoma, strictures
40
risk factors for AKI
aging >50, preop renal dysfunction, cardiac or hepatic failure, cardiac bypass, aortic cross clamp, arteriography, intra-aortic balloon pump, ruptured AAA, ischemic time, large volume of blood transfusion
41
anuric
<100 mL/day
42
polyuric
>2.5 L/day
43
oliguric
<400 mL/day
44
what kind of clamp do we want with AAA?
infrarenal
45
AKI preop treatment
balanced salt solution with minimize ADH and RAA release, attentuation of surgical stress
46
fluid replacement for periop AKI treatment
500-1000mL bolus for hourly urine output below acceptable levels
high risk patients: 0.5-1 mL/kg/hr
47
AKI perioperative treatment
fluid replacement
improve cardiac output
normalize systemic vascular resistance
48
diuretic use is
not recommended to prevent oliguria
49
early treatment of ___ causes has best outcomes
pre-renal AKI
50
which AKI is most difficult to treat?
intra-renal AKI
51
most common cause of AKI is
prolonged hypoperfusion
52
___ reduces mortality more than dialysis
prophylaxis
53
key strategy for AKI perioperative treatment
limiting magnitude and duration of renal ischemia
54
renal function decreases by ____ per decade
10%
55
CKD exists when GFR is
< 60 mL/min/1.73 m2 for 3 months
56
signs and abnormal labs do not appear until less than ___ of normal functioning nephrons remain
40%
57
when someone has 95% loss of renal function
uremia, volume overload, CHF
58
uremia
high uric acid, basically urine is floating in the blood and will need dialysis
59
stage I of CKD
kidney damage with normal GFR
60
stage II of CKD
GFR 60-89 mL/min/1.73 m2 with kidney damage
61
stage III of CKD
GFR 30-59 mL/min/1.73 m2
62
stage IV of CKD
GFR 15-29 mL/min/1.73 m2
63
Stage V of CKD
GFR < 15 mL/min/1.73 m2 with end stage failure
64
systemic effects of CKD
hypertension and congestive heart failure* (90% volume dependent, 10% secondary to increased renin), pericardial effusion, pericarditis, anemia, respiratory depression, fatigue, weakness, autonomic neuropathy
65
most common cause of death with CKD
ischemic heart disease
66
autonomic neuropathy can lead to
delayed gastric emptying
67
disequilibrium syndrome from dialysis
decreased Na+ = rapid increased cerebral edema, stupor, coma, CNS effects, seizures
68
hematologic effects from CKD
normochromic, normocytic anemia, decrease in erythropoietin, reduction in erythrocyte life secondary to dialysis, blood loss from frequent sampling, prolonged bleeding, decrease in platelet function
69
desmopressin (DDAVP) increases levels of
factor VIII
70
dialysis patients are at greater risk for ___
GI bleeding
71
endocrine and electrolyte changes from CKD
```
hyperparathyroidism
adrenal insufficiency
sodium wasting
hypocalcemia
hyperkalemia
```
72
mucosal changes can happen with CKD d/t ___ and considerations
inflammation; risk for GI bleed, consider H2 blockers or antacid, infection common
73
Hyperkalemia is a serious disturbance in patients with
renal disease
74
fatal dysrhythmias or cardiac standstill can occur when K+ levels reach
7-8 mEq/L
75
treatment for hyperkalemia
25-50 grams dextrose
10-20 units of regular insulin
50-100 mEq of sodium bicarbonate
hyperventilate (decreases K+ by 0.5 mEq)
76
physiologic effects of dialysis
hypotension, muscle cramping, anemia, nutritional depletion
77
hyperkalemia on ECG
peaked T waves then widen PR interval then sinusoidal wave
78
CaCl should be given
through a central line, slowly
79
Calcium Gluconate can be given
peripherally, slowly
80
fluid management
urine output 0.5-1 mL/kg/hr
| balanced salt solution 3-5mL/kg/hr with 500 mL bolus prn
81
what fluids are contraindicated in anuric patients
potassium containing solutions (LR)
82
intra-operative losses greater than ___ should be replaced with colloid 1:1
15%
83
how much K+ is in LR?
4 mEq
84
how much crystalloid without potassium should be given in renal insufficient patients?
2-3mL/kg/hr
85
insensible loss replacement in dialysis patients
5-10 mL/kg of D5w
86
if dialysis patients produce urine what solution would you use for insensible losses
0.45% saline
87
for every 50% reduction in GFR, serum creatinine ___
doubles
88
BUN:creatinine ratio is
10:1
89
BUN can be effected by
liver disease, excise, and keto diet
90
most reliable test for renal function
creatinine clearance
91
creatinine clearance measures
glomerular ability to excrete creatinine in urine
92
mild renal dysfunction creatinine clearance
50-80 mL/min
93
moderate renal dysfunction creatinine clearance
<25 mL/min
94
a creatinine clearance less than ____ requires dialysis
10
95
reduced protein binding may result in
increased sensitivity to drugs
96
which opioids are NOT removed by dialysis
morphine and meperidine metabolite
97
H2 blockers are highly dependent on
renal excretion
98
regional anesthesia in CKD is
well tolerated
99
major concerns for regional anesthesia in CKD patients
intolerance, coagulopathy, peripheral neuropathy, risk of infection
100
intravenous drugs in CKD patients
Vd is increased
decreased protein binding
low pH
renal excretion
101
which agents that we give frequently has less protein binding and don't need to be renally adjusted as much?
ketamine and benzos
102
is dexmeditomidine ok to use in renal patients?
yes, cleared by the liver
103
remifentanil has ____ clearance in patients with ESRD
reduced d/t decreased plasma esterases
104
Succinylcholine and renal disease
increases serum potassium 0.5 mEq/L
succinylmonocholine is renally excreted
uremic patients have cholinesterase deficiency
105
pancuronium and renal disease
AVOID IT
| 80% renally excreted
106
atracurium, cisatracurium, and mivacurium and renal disease
duration NOT increased in renal failure
| slower onset with cisatracurium and mivacurium
107
vecuronium and renal disease
30% excreted via renal system
| effects rapidly reversed with dialysis
108
rocuronium and renal disease
renal failure reduces clearance by almost 40%
| longer DOA
109
patients with ESRD generally require dialysis ____ after major surgery
24-36 hours
110
uremic patients may require replacement with
RBCs, FFP, colloids
111
common urologic procedures
cystoscopy, extra-corporeal shock wave lithotripsy, transurethral resection of the prostate, lap/robotic urologic procedures, open nephrectomy, renal transplant
112
cystoscopy
urologist uses a cystoscope to examine the urethra and bladder
can be diagnostic or intervention
cystoscope can be rigid or flexible
113
cystoscopy positioning
lithotomy
| risk for peroneal nerve injury
114
ESWL (extra-corporeal shock wave lithotripsy)
non-invasive treatment that uses high energy US waves to break up the calculi
outpatient under GA
hematuria is common
need ECG - R wave is used to trigger shocks
115
if there are kidney stones in the distal ureter
they need to be surgically removed
116
kidney stones aka ___ affect ___ of the population
nephrolithiasis, renal calculi, affect 9%
| made up of calcium
117
if calculi less than 5mm in diameter
expected to pass without intervention
118
if kidney stone 5-10 mm
medical management
119
if kidney stone >10 mm
unlikely to pass spontaneously
120
contraindications of ESWL
active UTI
uncorrected bleeding disorder or coagulopathy
distal obstruction
pregnancy
121
complications of ESWL
dose-dependent hemorrhagic lesions on kidneys
perforation, rupture, damage to colon, hepatic structures, lungs, spleen, pancreas, abdominal aorta or iliac veins
hematuria
diabetes, new-onset HTN, decreased renal function
122
most common complication with ESWL
hematuria
123
if ESWL fails
IR under fluoroscopy
124
if you do a spinal/epidural for a patient getting an ESWL what level do you want it to reach
T4/T6 level
125
anesthetic considerations for ESWL
discontinue ASA, anticoagulants, platelet inhibitors, NSAIDs 7-10 days prior to procedure
need negative urine culture
HCG if of child bearing age
laser eye protection for us and the patient
126
percutaneous nephrolithotomy
procedure to remove kidney stones 25 mm or smaller
usually a secondary surgery option if other fails
done under GA
rigid scope inserted in renal calyx under fluoroscopy
in prone or supine position
127
complications of percutaneous nephrolithotomy
pain, fever, UTI, renal colic, septicemia, bleeding, pneumothorax, hemothorax, anaphylaxis
128
TURP
scope placed through urethra to cut away obstructing lobes of the prostate
the bladder is distended and continuous irrigation is used
commonly done under GA
129
medical management used for BPH
alpha blocking agents - flomax/tamsulosin
130
what is the most common surgical procedure in men over 60
TURP
131
anesthetic risks with TURP are related to
the patient's age and associated comorbidities, not the procedure itself
132
anesthetic of choice for TURP
spinal anesthesia, d/t being able to detect complications
133
TURP syndrome!
rare but significant!
mortality as high as 25%
large amounts of fluid absorbed through the prostate
can happen within 24 hours of the procedure
134
TURP syndrome hallmark symptoms
fluid overload, water intoxication, hyponatremia, glycine toxicity
135
fluid overload in TURP syndrome
HTN, bradycardia, arrhythmia, angina, pulmonary edema, CHF, hypotension
136
water intoxication in TURP syndrome
confusion, restlessness, seizure, lethargy, coma, dilated sluggish pupils
137
hyponatremia in TURP syndrome
CNS changes, widened QRS, T wave inversion
138
glycine toxicity in TURP syndrome
NV, HA, transient blindness, myocardial depression
139
spinal block for TURP
up to T10
140
complications of TURP
volume overload w/ pulm edema, dilutional hyponatremia w/ hypoosmolality, cardiac effects, renal toxicity, hyperglycemia, hypothermia
less common: glycine absorption, bleeding, infection, bladder perf, skin burns
141
Na+ 120 will see
EKG changes
142
Na+ 115 will see
wide QRS
143
Na+ 100 will see
vfib/vtach
144
which cutting device has greater incidence of causing skin burns during TURP
MONOpolar
145
fluid absorption during TURP is dependent on
size of resection, duration of resection, irrigation solution pressure, number of venous sinuses open at a time, provider experience
146
up to ___ of fluid is absorbed per minute in TURP
30 mL
| up to 8 L in 2 hours
147
uptake of 1L of irrigant can decrease serum Na+ by
5-8 mEq/L
148
glycine is an amino acid that
acts as an inhibitory transmitter
149
excessive absorption of glycine can lead to
NV, fixed and dilated pupils, HA, weakness, muscle incoordination, TURP blindness, seizures, hypotension
150
TURP considerations
avoid Trendelenburg position!
limit resection to less than one hour
place irrigating solution less than 60 cm above prostate
monitor electrolytes
use a regional technique with light sedation
151
treatment for TURP syndrome
correct hyponatremia: 3-5% saline no greater than 100mL/hr
20 mg IV lasix
1 mg IV versed
PRBCs
intubate
investigate for DIC or primary fibrinolysis
152
increase sodium by ___ / hour or ___ /day in TURP syndrome
0.5 mEq; 8 mEq
153
Sodium goal in TURP syndrome
greater than 120 mEq/L
154
rapid reversal of hyopnatremia can result in
osmotic demyelination syndrome
155
laparoscopic urologic surgery anesthetic considerations
```
pneumoperitoneum
subcutaneous emphysema
alterations in perfusion
CO2 absorption potential of acidosis
increased intrabdominal and intrathoracic pressures
hemorrhage
```
156
upper tract robotic urologic surgeries
simple or radical nephrectomy, radical nephroureterectomy, nephron sparing surgery
157
pelvic robotic urologic surgeries
radical cystectomy, radical prostatectomy
158
robotic urologic surgery considerations
```
steep trendelenburg (+ lithotomy for prostatectomy), arms tucked, lasts 3-4 hours, do an airway assessment before extubation, EBL < 300mL, limit fluids until urethra is reconnected, large bore IV
DVT prophylaxis, eye protection, OGT, bair hugger, antibiotics, dexamethasone, remifentanil
```
159
nephrectomy
can be open or laparoscopic
| removing total or partial kidney
160
anesthetic considerations for nephrectomy
```
lateral jack knife position
CV compromise
third spacing and edema
hemodynamic monitoring
postop pain management
check pressure points
```
161
renal transplant
mainstay treatment for end stage renal disease
donors may be living or deceased
most frequent solid organ transplanted today
5 year survival rate is 70%
