Critical Care Flashcards
(129 cards)
1
Q
How do you calculate Cerebral Perfusion Pressure?
A
CPP = MAP - ICP = (2/3 DBP + 1/3 PP) - ICP
2
Q
Hypoxia causes _______ of cerebrovasculature.
A
vasodilation
3
Q
Hypotension leads to _________ of cerebrovasculature.
A
Vasodilation (therefore increased ICP)
4
Q
What defines a supraventricular tachycardia on EKG?
A
Rate > 100 w/ a QRS < 0.12
5
Q
Multifocal atrial tachycardia is associated with what disease processes?
A
COPD and Theophylline use
6
Q
What is the most common reentrant accessory pathway in AV reentrant tachycardia? What is the EKG characteristic? In what disease processes can it be seen?
A
Bundle of KentDelta wavesWolff-Parkinson-White syndrome
7
Q
What two electrolyte abnormalities are associated with ventricular tachycardia and polymorphic tachycardia?
A
hypokalemia and hyponmagnesia
8
Q
What EKG findings are seen in digoxin use?
A
gradual downward curve of the ST segment (causes multiple dysrhythmias and AV block)
9
Q
What EKG findings are seen in hypocalcemia?
A
increased QT interval
10
Q
What EKG findings are seen in hypothermia?
A
J-point elevation
11
Q
What EKG changes are seen in Brugada syndrome?
A
right BBB w/ ST eelvation in V1-3
predsiposes to sudden cardiac death
12
Q
What EKG changes are seen in SAH?
A
peaked T waves and ST depression
13
Q
What are the classes of Antiarrythmics?
A
Class 1 (Na Channel blockers)
Class 2 (B blockers)
Class 3 (K channel blockers)
Class 4 (Ca channel blockers)
14
Q
Stimulation of Andrenergic Alpha Receptors leads to ______.
A
vasoconstriction
15
Q
Stimulation of Andrenergic Beta-1 receptors leads to ______.
A
increases cardiac output (chronotropy) and strength of contraction (inotropy)
16
Q
Stimulation of Andrenergic B-2 Receptors leads to ______..
A
vasodilation
17
Q
Activation of dopamine receptors causes ______ of cerebral, renal, coronary, and mesenteric vasculature.
A
vasodilation
18
Q
What receptors does dobutamine acitvate?
A
B1 agonist, mild B2 and A2 agonist
19
Q
What are the effects of dobutamine?
A
inotropic, peripheral vascular dilation, increases cardiac output, decrease in SVR
No change in BP
side effect of tachycardia
20
Q
At low doses, dopamine causes _______ while at high doses it causes ________.
A
vasodilation; vasoconstriction
21
Q
Phenylephrine affects predominantly _____ receptors.
A
alpha 1
22
Q
What kind of pressor is vasopressin?
A
norandrenergic
23
Q
What are contraindications for norepinephrine use?
A
renal failure
24
Q
What electrolyte abnormality enhances digoxin toxicity?
A
hypokalemia
25
When therapeutic, what are the effects of digoxin?
AV and SA node conduction slowing
26
What are the treatments for digoxin toxicity?
K, Mg, Lidocaine, Digoxin antibody, and charcoal
27
What are the cardiovascular effects of furosemide?
increases SVR and decreases CO
28
What medication can block the response of furosemide?
NSAIDs
29
What are the major side effects of furosemide?
ototoxicity, hypokalemia, hypomagnesemia, hypochloremia, and metabolic alkalosis
30
What receptors does labetalol act upon? What are its effects?
alpha and beta receptors; lowers BP but does not increase HR or increase CO
31
What is the treatment for methemoglobinemia? What cardiac drug can cause methemoglobinemia?
Methylene blue
Nitroglycerine
32
What cardiac drug can cause cyanide toxicity?
Sodium nitroprusside
33
What are the treatments for air embolism?
left lateral decubitus position, hyperbaric oxygen, or removal of air embolism
34
Describe the Bohr effect. What causes respective right and left shifts?
changes in the oxygen dissociation curve to either facilitate oxygen absorption or bonding with hemoglobin.
Right: tissues with decreased oxygen affinity
- increases in acidity
- CO2- temperature
- 2,3-DPG
Left: lung, increased affinity for oxygen
- opposite as above
35
What is characteristic of ARDS on BAL?
high protein levels
36
B2 agonists have what affect on the respiratory system? What are their potential side effects?
bronchodilators
at high doses can cause tachycardia, hypokalemia, or tremors
37
What is the mechanism of theophylline?
increase cAMP
38
Inhaled anticholinergics include ______ and ______. They cause _______ .
Atropine and Ipratropium
decreased parasympathetic input (decreased bronchoconstriction)
39
What is the duration of vecuronium?
30 minutes
40
What is the duration of pancuronium?
1 hour
41
Succinylcholine is what type of paralytic? What electrolyte abnormality can it cause?
depolarizing blocker
hyperkalemia
42
What is normal tidal volume in adults?
5-6 cc/kg
43
What urine casts are seen in Prerenal conditions?
hyaline and finely granular casts
44
What urine casts are seen in Acute Tubular Necrosis?
epithileal and course granular casts
45
What urine cases are seen in Acute Interstitiial nephritis?
white cell casts
46
What urine cases are seen in Acute Glomerulonephritis?
red cell casts
47
When should dialysis be considered in acute renal failure?
K > 6.5, blood pH < 7.1, refractory hypovolemia w/ BUN > 80, Na < 120 or > 155, or overdose of dialyzable drug
48
Which of the renal tubular acidosis have hyerkalemia and which have hypokalemia?
Hyperkalemia: RTA 4
Hypokalemia: RTA 1 and 2
49
Where do loop diuretics act upon? What is the mechanism?
ascending limb of loop of henley
prevent sodium absorption by interfering with Na-K-Cl pump
50
What is the mechanism of thiazide diuretics?
inhibit Na-Cl cotransporter
51
What are examples of K sparing diuretics? Where do they act?
Amiloride, spironolacotone
cortical collecting tubules
52
Where does mannitol exert its effect?
proximal tubule and loop of henley
53
What medication treats neurogenic or atonic bladder?
Bethanechol
54
Describe the HR, SVR, CO, and CVP. Cardiac Shock
Decreased HRIncreased SVRDecreased COIncreased CVP
55
Describe the HR, SVR, CO, and CVP. Hypovolemic Shock
Increased HRIncreased SVRUnchanged/Decreased CODecreased CVP
56
Describe the HR, SVR, CO, and CVP. Septic Shock
Increased HRDecreased SVRIncreased COUnchanged/Decreased CVP
57
What acid/base abnormality can occur with massive blood transfusion? What electrolyte abnormalities?
Metabolic alkalosis
Hypocalcemia and Hyperkalemia (sometimes hypokalemia secondary to the alkalosis)
58
What causes the reaction seen in febrile nonhemolytic reaction?
cytokines (IL-1, IL-6, TNF)
59
What causes transfusion related lung injury? What is it similar to clinically? How does it differ?
pulmonary agglutinin reaction
ARDS
resolves in usually 4 days
60
What are the treatments for TTP?
plasmapharesis, exchange transfusions, antiplatelet agents, and rarely splenectomy
DO NOT TRANSFUSE PLATELETS
61
What are the treatments for ITP?
steroids and splenectomy
62
How long does the platelet effect of ASA last?
10 days i.e. the life of the platelet
63
Which coagulation pathway affects PTT?
intrinsic
64
Which coagulation pathway affects PT?
extrinsic
65
What components make up the intrinsic pathway?
XII, XI, iX w/ VIII followed by the shared pathway
66
What components make up the extrinsic pathway?
Tissue thromboplastin, VII followed by the shared pathway
67
What is the shared pathway for intrinsic and extrinsic coagulation cascades?
X (w/ V) -> IIThrombinI (Fibrinogen) -> Fibrin (w/ XII) -> Stabilized fibrin
68
What coagulation lab measures are affected by DIC?
elevated PT, PTT, and bleeding time
69
What is the treatment for DIC?
- treat the causative agent- heparin- cryoprecipitate- platelets- whole blood
70
What are the vitamin K dependent coagulation factors?
protein C and S, factors VIII. IX. X. II
71
Hemophilia B is caused by what factor deficiency? What is the genetic inheritance? What are the abnormal lab values? What's the treatment?
factor IX
X-linked recessive
increased PTT, normal PT, normal bleeding time
FFP
72
What is the genetic inheritance of factor VIII deficiency? What's it called? What is the treatment?
X-linked recessiveHemophilia ACryoprecipitate
73
What is the treatment for vWF disease? What's the treatment?
autosomal dominantcryoprecipitate
74
What coagulation factor deficiencies causes hypercoagulablity? What are the clinical manifestations?
protein C, S, and antithrombin III
venous thrombosis
75
What is the mechanism of action for heparin?
increases the action of antithrombin III
76
What is the reversal agent for heparin?
protamine sulfate
77
How do you calculate the expected degree of respiratory compensation for metabolic acidosis and alkalosis?
Acidosis: PCO2 = 1.5 x bicard + 8
Alkalosis: PCO2 = 0.7 x bicarb + 20
78
How do you calculate an anion gap?
Na - (Cl + HCO3)
79
RTA type 2 causes what type of acidosis? What is the electrolyte lost?
normal anion gap metabolic acidosis
HCO3
80
What acid base abnormality can occur from diuretic use? What diuretics classically cause this?
metabolic alkalosisloop and thiazide diuretics
81
How does urine osmolality differ between central and nephrogenic DI?
Central: < 200 mOsm/LNephro: 200 - 500 mOsm/L
82
Hyperglycemic non-ketotic syndrome can cause what electrolyte abnormality?
hypovolemic hypernatremia
83
What are the diagnostic criteria for SIADH?
urine osmolarity > serum osmolarity
serium Na < 135
serum osmolarity < 280
urine Na > 20 over 24 hours
84
What are the treatments for SIADH?
- fluid restriction
- demecoccline (induces nephrogenic DI)
- furosemide w/ 3%
85
What is the treatment for hyperkalemia w/ EKG changes?
- stabilize cardiac membranes w/ calcium gluconate- insulin- furosemide
86
Where is magnesium absorbed in the nephron?
loop of henle
87
What hormone is affected by hypomagnesemia?
low parathyroid hormone
88
Blood transfusions can cause what calcium abnormality?
hypocalcemia (citrate binding to Ca ions)
89
Hypocalcemia causes what neuromuscular findings?
hyperreflexia, tetany, and seizures
90
:Thiamine deficiency causes what abnormalities?
berberi heart disease, Wernicke encephalitis, peripheral neuropathy, and lactic acidosis
91
Chromium deficiency causes what abnormality?
insulin resistance
92
What element deficiency can impair wound healing and increase infection risks?
Zinc
93
What macronutrient should be limited in patients with respiratory failure/COPD?
carboydrates (produce highest amount of CO2)
94
What dietary changes help with hepatic encephalopathy?
increased branched chain amino acids to decrease aromatic uptake across BBB
95
What test is used to evaluate adrenal insufficiency?
ACTH stimulation test
96
How do you distinguish primary vs secondary hypercortisolism?
dexamethasone suppression test
97
What are the clinical manifestations of hyperaldosteronism?
hypernatremia, hypokalemia, metabolic alkalosis, hypertension, increased urine output
98
What is struma ovarii?
functioning thyroid tissue in an ovarian malignancy
99
What is the mechanism of Propylthiouracil?
inhibits thyroid hormone synthesis and conversion of T4 and T3
100
What is the most lethal clinical sequela of hypothyroidism?
myxedema coma
101
What is MEN I? What is the inheritance pattern?
autosomal dominant
tumors of the parathyroid, pancreas, and pituitary gland
102
What is MEN IIa? What is the inheritance pattern?
autosomal dominant
parathyroid hyperplasia, medullary thyroid cancer, pehochromocytoma
103
What is the medical treatment for pheochromocytoma?
phenoxybenzamine
104
What is MEN IIb?
medullary thyroid cancer, pheochromocytoma, mucosal neuromas, intestinal ganglioneuromas, Marfinoid habitus
105
What two common organisms can cause necrotizing fasciatis? What's the time frame of presentation? What is the treatment?
Clostridia and B-hemolytic strep48 hours post oppenicillin and debridement
106
What is the most common cause of meningitis after basilar skull fractures? When does it present?
strep pneumo usually occurs within 72 hours
107
What is the most common organism for ventriculoperitoneal shunt infections?
staph epi
108
What are the serious side effects of aminoglycosides?
ATN (reversible), hearing loss (irreversible), vestibular dysfunction, and worsening of myasthenic syndrome
109
What is the renal side effect of amphotericin B?
distal tubule RTA
110
What are the effects of ketamine on CBF, metabolic rate, and ICP?
CBF: increasedCMRO2: increasedICP: increased (controversial)
111
Which inhalational anesthetic causes the least increase in CBF?
isoflurane
112
What is the side effect of enflurane?
lowers seizure threshold
113
What is the effect of thiopental on CBF and CMRO2?
decreased both
114
What is the effect of Etomidate on CBF, CMRO2, and CPP?
decreased CBF and CMRO2 while preserving CPP
115
What is an important side effect of Etomidate use?
suppresses the adrenocortical response to stress
116
What are the effects of fentanyl on CBF and CMRO2?
decreases both
117
What anesthetic agents increase CBF?
in increasing order:Nitrous oxide, isoflurane, enflurane, ketamine, and halothane
118
What is the antidote for lead poisoning?
EDTA, 2,3-dimercaptopropanol (BAL), penicillamine
119
What is the antidote for arsenic poisoning?
BAL
120
What is the antidote for mercury poisoning?
penicillamine
121
What is the antidote for gold poisoning?
BAL and penicillamine
122
What is the antidote for iron poisoning?
deferoxamine
123
What is the antidote for organophosphate toxicity?
2-puridine aldoxime methochloride (PAM)
124
What is the antidote for tylenol toxicity?
N-acetylcysteine (inactivates toxic metabolites)
125
What are the metabolic effect of ASA toxicity?
early respiratory alkalosis followed by late metabolic acidosis
126
How is methanol and ethylene glycol intoxication treated?
ethanol (saturates alcohol dehydrogenase thus preventing formaldehyde formation)
127
What medications increase or decrease dilantin levels?
Increase: cimetidine, warfarin, isoniazid, and sulfa drugs
Decrease: carbamazepine
128
What electrolyte abnormality increases the likelihood of digoxin toxicity?
hypokalemia
129
What is the mechanism of Baclofen?
GABA agnosit
