CV: Pathophysiology Flashcards
1
Q
When is the risk of reinfarction highest after MI?
A
First 30 days
2
Q
What is the bare minimum time recommended to have elective surgery after MI?
A
4-6 wks
3
Q
AT what time frame does risk for reinfarction after MI decrease to 6%?
A
> 6 months out
4
Q
Which procedures are considered high cardiac risk beased on the surgical procedure alone? Risk is > 5%
A
Emergency surgery
OPen aortic surgery
Peripheral vascular surgery
Long surgeries with significant volume shifts and or blood loss
5
Q
Which procedures are considered intermediate cardiac risk based on the surgical procedure alone? Risk is 1-5%
A
Carotid endarterectomy
Head and neck surgery
Intrathoracic/intraperitoneal surgery
Orthopedic
Prostate surgery
6
Q
Which procedures are considered low cardiac risk beased on the surgical procedure alone? Risk is <1 %
A
Endoscopic procedures
Cataract surgery
Superficial procedures
Breast surgery
Ambulatory procedures
7
Q
What is the level of clinical impairment of New York Heart Association class 1.
A
No symptoms with physical activity.
8
Q
What is the level of clinical impairment of New York Heart Association class 2.
A
Symptoms appear during normal activity but no symptoms at rest
9
Q
What is the level of clinical impairment of New York Heart Association class 3.
A
Symptoms appear with less than normal activity but no symptoms at rest
10
Q
What is the level of clinical impairment of New York Heart Association class 4.
A
Symptoms appear with minimal activity or even at rest
11
Q
What NYHA class associates should be referred to a cardiologist before having an intermediate or high risk surgery requiring GA?
A
3 or 4
12
Q
So long as a patients preop assessment suggests stable cardiac disease it would be ok to do which NYHA classes under a MAC?
A
3,4
13
Q
Infarcted myocardium releases what 3 important biomarkers? Which are more sensitive?
A
- CKMB
- Troponin I
- Troponin T
T I and T T are more senstive for dx MI
14
Q
When will CKMB, Troponin I, and Troponin T be initially elevated?
A
All at 3-12 hours!
15
Q
When will peak elevation occur for CKMB, Troponin I, and Troponin T?
A
CKMB 24 h
Troponin I 24 h
Troponin T 24-48 h
16
Q
How long until CKMB, Troponin I, and Troponin T return to baseline?
A
CKMB up to 3 days
Troponin I up to 10 days
Troponin T up to 14 days
17
Q
Which leads are best for detecting dysrhythmias?
A
II
V1
18
Q
Which leads are best for detection of ventricular ischemia?
A
V3, V4, V5
4 if you had to choose!
19
Q
Monitoring which 3 leads has an ischemic detection of up to 96%?
A
II V4 V5
20
Q
Higher filling pressures are required to prime the poorly _____ ventricle
A
compliant
*maintain nsr and atrial kick
21
Q
What does it mean that for any condition that reduces ventricular compliance, the CVP and PAOP may overestimate LVEDV?
A
Because filling pressures are higher to compensate!
22
Q
Heart failure with preserved ejection fraction is S or D failure?
A
D
23
Q
Heart failure with reduced ejection fraction is S or D failure?
A
S
24
Q
3 compensatory mechanisms for Systolic heart failure?
A
Increase SNS
Increase RAAS
Increase preload
25
ANP is released due to _
Atrial stretch
26
What 2 effects does ANP cause?
Vasodilation
Diuresis
27
To confirm a HTN dx when should BPs be taken?
twice. 1-2 weeks apart
28
What is a normal BP?
< 120/80
29
What is an elevated BP?
120-129 & <80
30
HTN stage 1 values
130-139 or 80-89
31
HTN stage 2 values
> 140 or Greater than 90
32
HTN stage 3 = hypertensive crisis values
> 180 SBP and or > 120 DBP
33
HTN can be primary or secondary. What % of cases are primary (no identifiable cause)
95
34
Cerebral perfusion pressure remains constant with a MAP between
50-150
35
What exaggerated effects will pts with HTN have during induction/intubation?
Exaggerated hypotension with induction
Exaggerated hypertension with DL
36
What are second line treatments for vasoplegia caused by the pt taking their ACEI or ARB the day of surgery?
Vasopressin, Terlipressin, Methylene Blue
37
What preop pressure should delay an elective procedure?
>180 over > 110
38
Hypertensive crisis vs emergency?
Crisis is > 180/120
Emergency is evidence of end organ damage
39
Which BP is higher in coarctation of the aorta? Upper or lower limb
Upper
40
What do CCB (dihydropyridines) end in?
-dipine
41
Whuch CCB are (non-dihydropyridines)?
Verapamil and Diltiazam
(they do not end in -dipine line dyhydropyridines
42
What is the biggest difference between dihydropyridines and non-dihydropyridines? *Hint: where the drug targets
dihydropyridines: target the vasculature
non dihydropyridines: target the myocardium > vessels
43
Does Na Nitroprusside target the A or V more?
EQUALLY
44
Where do loop diuretics work? Which transporter do they inhibit?
Ascending loop of Henle
Na K 2Cl
45
Where do thiazide diuretics work? What transporter do they inhibit
Distal convoluted tubule
Na Cl transporter
46
What are the 2 K sparing diuretics?
Triamterene, amiloride
47
Where do K sparing diuretics work?
Principal cells
48
Which diuretic is an aldosterone antagonist?
Spironolocatone
49
Where do aldosterone antagonists work?
Principal cells
50
There are 3 types of voltage gated Ca channels. What are they?
L -ype = long lasting or slow channel
N-type= Neural
T-type = Transient
51
All clinically used CCB bind to the alpha 1 subunit of the _ type Ca channel
L
52
What are the 2 best CCB to control HR?
Diltiazem
Verapamil
52
In what order (highest to lowest) do CCB impair contractility?
Verapamil > Nifedipine > Diltiazem > Nicardipine
53
What drug class is Clevidipine?
CCB. Outlier. Not a dihyropyridine or non dihyropyridine
54
MOA of Clevidipine
Arterail vasodilation. --> Does not affect preload
55
What sanitary precautions need to be taken with Clevidipine?
It is prepared as a lipid emulsion
Discard vial after 12 hours
56
Contraindications to receiving Clevidipine?
Allergies to: soy, egg
57
What medical condition would be a contraindication to receiving Clevidipine?
Severe aortic stenosis
58
What is starting and max dose of Clevidipine?
start: 1 mg/hr
max: 16 mg/hr
59
How is Clevidipine metabolized?
tissue esterases
** hepatic/renal impairment is no factor
60
The pericardium is composed of 2 layers. What are they?
Visceral
Parietal
61
How much fluid is in the pericardium?
10-50 mL clear fluid that separates the visceral and parietal layer
62
What is constrictive pericarditis?
Caused by fibrosis. Makes it hard for ventricles to fully relax during diastole
63
Treatment for constrictive pericarditis?
pericardiotomy
64
Treatment for acute pericarditis?
Usually resolves spontaneously
Can give drugs to relieve pain:
Corticosteroids
Oral analgesics
Salicylates
65
Causes of constrictive pericarditis?
Cancer (radiation)
Cardiac surgery (scar tissue)
Rheumatoid Arthritis **
Tuberculosis **
Uremia **
66
Causes of acute pericarditis?
Infection is most common
Dresslers syndrome
Lupus
Scleroderma
Trauma
Cancer (radiation)
67
S/S constrictive pericarditis?
Kussmauls sign (JVD during inspiration)
Pulsus paradoxus (SBP decreases > 10 mmHg during inhalation)
Increased venous pressure signs!
68
S/S acute pericarditis?
Pain with breathing (hurts taking a breath in) Relived by leaning forward
Pericardial friction rub
ST elevation with normal enzymes
Fever
69
What is a pericardial effusion?
Accumulation of fluid inside the pericardial sac
70
What is the best method to diagnose cardiac tamponade?
TEE
71
Cardiac tamponade results from fluid accumulation inside the __
pericardium
72
What does pressure volume loop look like with cardiac tamponade?
Shift to the L
Loop is narrower
Decreased ventricular compliance
73
What is Becks Triad associated with? What are the 3 components?
Cardiac tamponade
Hypotension
Jugular venous
Muffled heart tones
74
Is pulsus paridoxus seen in cardiac tamponade? What is it?
Yes
Decreased SBP by > 10 mmHg during inspiration
75
Why would cardiac tamponade lead to reduced ekg voltage?
Excess fluid around the heart attenuates the electrical signal recorded by the electrodes
76
What are the 2 ways to remove excess pericardial fluid?
Pericardiocentesis
Pericardiostomy
77
Why is spontaneous ventilation preferred with cardiac tamponade?
PPV van increase thoracic pressure and make it worse
78
What is preferred anesthetic for pericardiocentesis?
Local anesthesia with spontaneous ventilation to maintain spontaneous stability
79
If a general anesthetic is required for a pericardiocentesis, what is your main concern?
Maintain myocardial function, remember there is an increase in SNS tone for compensation- do not want to knock that out or can lead to CV collapse
80
What usually causes infective endocarditis?
Bacteria in the bloodstream!
81
Why have we gotten more strict about who receives prophylactic abx for infective endocarditis?
Due to concerns about abx resistant bacterial strains
Due to the fact that very few cases of IE can be prevented with prophylactic abx
82
What are the general current guidelines to give abx coverage to prevent infective endocarditis?
Should only be give to those at HIGH risk of developing IE and the patient is more likely to suffer an adverse outcome from IE
83
What are some patient related risk factors (conditions) associated with the highest rate for developing IE
Previous IE
Prosthetic heart valve
Unrepaired cyanotic congenital heart dz
Repaired congential heart defect if the repair is < 6 mo old
Repaired congenital heart dz with residual defects
Heart transplant with valvuloplasty
84
What are some procedure related risk factors associated with the highest rate for developing IE
"DIRTY" procedures
Dental procedures involving gingival manipulation and/or damage to mucosa lining
Respiratory procedures that perforate mucosal lining with an incision or bx
Bx of infective lesions of the skin or muscle
85
What is the most common autosomal dominant CV disease?
Obstructive hypertrophic cardiomyopathy
86
What is the most common autosomal dominant CV dz?
Obstructive Hypertrophic Cardiomyopathy
87
What are 3 other names for obstructive hypertrophic cardiomyopathy?
Hypertrophic obstructive cardiomyopathy
Asymmetric septal hypertrophy
Idiopathic hypertrophic sub-aortic stenosis
88
Left ventricle outflow tract obstruction is caused by 2 things:
1. Congenital hypertrophy of the inter-ventricular septum
2. Systolic anterior motion (SAM) of the anterior leaflet of the mitral valve
89
What is systolic anterior motion?
Systolic anterior motion of the anterior leaflet of the mitral valve during systole. It produces a mechanical obstruction to flow through the left ventricular outflow tract
90
What 3 surgeries can be done to repair obstructive hypertrophic cardiomyopathy?
1. Septal myomectomy- removes a portion of the inter-ventricular septum and improves the transmural pressure gradient
2. Alcohol injection into the septeal perforator arteries causing ischemic injury to the septum which improves transmural pressure gradient
3. Mitral valve replacement can reduce SAM
91
Dual antiplatelet therapy after PCI usually consists of ASA and which 2 possible drugs?
Clopidogrel
Ticlopidine
92
When is the risk of restenosis greatest after getting a stent placed?
30 days
93
How long should you wait to have elective surgery after angioplasty without stent?
2-4 weeks
94
How long should you wait to have elective surgery after having a bare metal stent placed?
30 days but 3 months is preferred
95
How long should you wait to have elective surgery after having a drug eluding stent placed due to stable ischemic heart disease?
First generation DES = 12 months minimum
Current generation DES= 6 months
96
How long should you wait to have elective surgery after having a drug eluting stent placed due to ACS?
12 months minimum
97
How long should you wait to have elective surgery after a CABG?
6 weeks (3 months preferred)
98
If on DAPT what are the guidelines surrounding Aspirin continuation before surgery?
If not absolutely contraindicated- cont the ASA
If absolutely contraindicated, stop the ASA at least 3 days before surgery
99
If on DAPT what are the guidelines surrounding Clopdogrel continuation before surgery?
Stop 7 days before
100
If on DAPT what are the guidelines surrounding Ticlopidine continuation before surgery?
Stop 14 days before surgery
101
What can occur if air enters the venous line of the bypass pump?
Air lock
102
There are 2 kinds of pumps that propel blood through the patients circulation during bypass, what are they?
Roller Roller
Centrifugal Pump
103
What are 3 main things to know about the roller clamp?
1. Creates an occlusion point which is traumatic to blood cells
2. Pump flow remains constant regardless of afterload, can lead to rupture of the arterial inflow tubing
3. More likely to entrain air if the venous reservoir runs dry, which can lead to air embolism
104
What are 3 main things to know about a centrifugal pump?
1. It is non-occlusive so less traumatic to blood cells
2. Reduced air of air embolism compared to roller pump
3. The pump flow decreases when confronted by high afterload- less risk of line rupture
****Preffered over a roller clamp
105
What portion of the bypass machine replaces the lungs?
Oxygenator
106
What are the 2 kind of oxygenators that can be used for a bypass machine?
Membrane oxygenator: uses blood-membrane-gas interface
Bubble oxygenator: Does not use a membrane, blood gas interface. Higher risk of cerebral air embolism
107
Which type of oxygenator is preferred on pump?
MEMBRANE!
108
The bypass circuit can be primed with which 5 potential solutions?
Blood
A balanced salt solution:
Mannitol
Albumin
Heparin
BIcarbonate
109
What is the main issue that arrises when the bypass circuit is primed with anything except for blood?
Hemodilution
110
What are the most likely times the patient will experience awareness?
Sternotomy is #1
Rewarming is #2
111
What does ACT need to be to go on bypass pump?
> 400
112
What should be used if the patients has allergy to heparin or hx of HIT?
Avoid Heparin and use Bivalirudin, Hirudin, or another factor 10 inhibitor
113
What is ideal SBP right before aortic cannulation for bypass?
90-100
114
How is the heart "retsarted" at the end of CABG after cardioplegia had been given?
Infusing the coronary circulation with warm normokalemic blood
115
What are the 2 routes cardioplegia can be given?
Antegrade: into aortic root
Retrograde: into coronary sinus
116
The patients temp during bypass (low) can lead to more CO2 being dissolved in the blood therefore a lower pH. which device corrects the temperature and which does not? Which is associated with better outcomes in adults? Pedi?
Alpha-stat: does not
pH-stat: does
Alpha =adults
Pedi= pH stat
117
What is the purpose of a LV vent on bypass?
Removes blood from the LV. Blood usually comes from the thesbian and bronchial circulation (anatomic shunt)
118
How does Protamine work?
Forms an acid/base complex with heparin
119
As a general rule, how much Protamine reverses 100 U heparin?
1 mg
120
What are 2 main complications of Protamine you should always think about when pushing it?
1. hypotension
2. pulmonary hypertension!!
*Push it slow **
121
What are 4 contraindications to intraaortic balloon pump?
1. Severe aortic insufficiency
2. Descending aortic disease (aneurysm)
3. Severe PVD
4. Sepsis
122
Where should the tip of the intraaortic balloon pump be positioned?
2 cm distal to the left subclavian artery.
*A more proximal position can lead to occlusion of the left common carotid and or brachiocephalic arteries
123
2 main objectives of IABP?
Decrease afterload
Increase coronary perfusion
124
Which portion of the EKG correlates balloon deflation of IABP?
R wave
125
IABP can be set to inflate with every beat (1:1 ratio) or 1:2 1:3 to facilitate _
weaning
126
What kind of medicine would a patient on long term IABP require?
Anticoagulation
127
3 most common complications of IABP?
thrombocytopenia, vascular injury, infection at the insertion site
128
Can yo have an LVAD placed with PFO, aortic insufficiency, tricuspid regurgitation?
No
129
Pump flow of an LVAD is highly dependent on what 3 things?
Preload
Afterload
pump speed
130
What is the most common cause of death with LVAD?
Sepsis
131
How can LVAD cause coagulopathy and PLT dysfunction?
Mechanical shear stress
132
What kind of medicine would a patient have to be on if they have an LVAD?
Long term anti-coagulation
133
What is the problem with low preload and high pump speed with an LVAD?
Suction event
134
How does Crawford classification system work?
Based on which region of the aorta is affected
135
Characteristics of Stanford and DeBakey classes
Reference apex
136
When is AAA surgery recommended? (size)
When it exceeds 5.5 cm or if it grows more than 0.6-0.8 cm per year
137
What is the classic triad of AAA rupture?
Hypotension
Back pain
Pulsatile abdominal mass
*BUT this triad only presents in 50% patients
138
Where do most AAA rupture into?
Left retroperitoneum
139
How many posterior spinal arteries are there?
2
140
What portion of the cord does that posterior spinal a. cover?
1/3 posterior
141
How many anterior spinal arteries are there?
1
142
What part of the SC is perfused by the anterior spinal a.?
Anterior 2/3
143
What kind of artery is the artery of Adamkiewicz
Radicular
144
What portion of the cord does the artery of Adamkiewicz usually originate from?
T8-T12
145
What portion of the cord does the Artery of Adamkiewicz perfuse?
Anterior. Thoracic and lumbar regions.
146
What is Becks SYNDROME?
(Anterior spinal artery syndrome)
When flow to the anterior cord is diminished
147
What sensation is preserved with anterior spinal artery syndrome?
Touch and proprioception
148
Does increased or decresead CSF help with spinal cord perfusion?
decreased
149
During aortic x clamp that is above the Artery of Adamkiwicz, what is the ideal MAP maintained?
100
150
What is Amaurosis fugax and what is it a sign of?
Blindness in one eye
Impeding stroke
151
What levels do superficial and deep cervical blocks cover?
C2- C4
152
CPP equation
MAP - CVP or ICP (whichever is higher)
153
BP goals for DURING cross-clamping
Maintain normal or slighly elevtaed
154
BP goals AFTER cross-clamping
Keep BP < 145
155
Consequence of carotid body denervation?
Reduced ventilatory response to hypoxia
*Problem with hx BL CEA
156
ACT goal for carotid stenting
> 250
