Pathphysiology Flashcards
1
Q
What is the definition of shock?
A
A serious and life threatening condition resulting in tissue hypoperfusion
2
Q
Is hypertensive shock similar to emotional shock?
A
No they should NOT be confused
3
Q
What is the end result in every type of shock?
A
Hypotension
4
Q
How do we calculate shock index?
A
Shock index = heart rate / systolic BP
5
Q
What is the normal range for shock index?
A
0.5-0.8
6
Q
What mechanism does shock operate on?
A
Positive feedback
7
Q
What is the effect of inflammatory mediators being released and causing increased blood flow to an area?
A
The blood is being diverted and starving other areas of blood/oxygen and therefore those areas then release their own inflammatory mediators
8
Q
What happens when the cells begin to suffer from hypoxia injury?
A
They begin to fail and the circulatory system collapse
9
Q
How many different types of shock are there and what are they?
A
4 types
~ hypovolaemic
~ cardiogenic
~ distributive
~ obstructive
10
Q
What is the problem associated with hypovolemic shock?
A
There is a fluid loss problem
11
Q
What type of things can cause hypovolemic shock?
A
Dehydration, sickness, diarrhoea, haemorrhage (internal or external), burns and diabetic ketoacidosis
12
Q
In hypovolemic shock is the sympathetic system working more or less? And what effect does this have?
A
Working more (more active) which leads to vasoconstriction to maintain BP
13
Q
Are organs well or poorly perfused in hypovolemic shock, and why?
A
Poorly, because there is reduced blood flow
14
Q
Is cardiogenic shock a fluid or blood loss problem?
A
No it’s a pumping problem
15
Q
What happens to the heart during cardiogenic shock?
A
It fails to pump effectively
16
Q
What can cause cardiogenic shock?
A
Large myocardial infarction,arrhythmias or heart failure
17
Q
What happens to the sympathetic system during cardiogenic shock?
A
It is over active and therefore leads to vasoconstriction
18
Q
Is the venous pressure high or low in cardiogenic shock, and what effect does this have?
A
High pressure, leading to fluid extraction and oedema
19
Q
What causes distributive shock?
A
An inappropriate peripheral vasodilation that is causing pooling of blood or fluid in the tissues.
20
Q
What are the 3 types of distributive shock?
A
Septic, neurogenic and anaphylaxis
21
Q
What is happening during septic shock?
A
You have an ongoing release of inflammatory mediators in response to infective organisms
22
Q
After adequate fluid resuscitation does sepsis persist or subside?
A
Persists
23
Q
What happens during an anaphylaxis shock?
A
There’s a huge release if histamines
24
Q
What happens during neurogenic shock?
A
There is a loss of nerve supply to the small vessels that prevent vasoconstriction
25
During distributive shock do you see an increase or decrease in SVR
Decrease because the vessels are dilated and you have caused hypovolemia
26
What type of shock is classified as a medical emergency?
Obstructive shock
27
What is obstructive shock?
When there is an obstruction to blood flow
28
Give 3 examples of things that could cause obstructive shock
- cardiac tamponade
- pulmonary embolus
- aortic stenosis (an obstruction of the left ventricle flow tract)
29
During obstructive shock is the sympathetic system more or less active?
More active which leads to vasoconstriction
30
During obstructive shock are the organs well or poorly perfused?
Poorly as you have a reduced blood flow
31
In obstructive shock what does back pressure lead to?
Venous congestion
32
What are the two stages of shock?
Initial and refractory
33
What’s another way to describe initial shock?
Compensated shock
34
What’s another way of describing refractory shock?
Decompensated shock
35
Describe why lactic acid builds up in compensated shock
The hypoperfusion of tissues leads to anaerobic respiration starting and so you get the build up of lactic acid
36
Does irreversible cells damage occur in compensated or decompensated shock?
Decompensated shock
37
What are the 4 things you need to do when you are treating a patient in hypotensive shock?
- keep the patient warm
- seek senior help immediately
- try to identify the cause (must be reserved for successful treatment)
- give 100% oxygen and give IV normal saline
38
How much saline should an adult receive in hypotensive shock?
1000ml stat
39
How much saline should a frail or elderly patient receive in hypotensive shock?
500ml
40
How much saline should a patient suspected of cardiogenic shock receive?
500ml
41
How much saline should a child receive in hypotensive shock?
Should be calculated on their body weight (20mg/kg)
42
What classifies a patient to be in hypertensive shock?
A sudden BP increase of 180/110 or more
43
What blood pressure do you usually see in patients who are in a hypertensive emergency?
220/120
44
What do you need to ensure you assess for if you suspect a patient is in a hypertensive emergency?
End organ damage
45
What is the most common cause of a hypertensive emergency?
Idiopathic hypertension
46
What are the secondary causes of a hypertensive emergency?
- pregnancy
- renal disease
- phaeochromocytoma
47
If you think a patient might have a hypertensive emergency but after assessment show now signs of end organ failure what are they then categorised as?
A hypertensive urgency
48
How should you treat a patient in a hypertensive emergency?
- Take regular BP measurements
- Gain IV access and carry out routine bloods
- ABCDE as required
- Seek senior help
49
Why do you have to slowly titrate the BP of patients in a hypertensive emergency?
Because if you drastically decrease the BP the body will not like that as much as it doesn’t like the high BP and will then go into a different type of shock
50
How do we usually treat a hypertensive urgency?
With oral medication
51
What is the mneumonic that we use to consider all the possible causes of pain?
VINDICATE
52
What does VINDICATE stand for?
V- vascular
I- Infection
N- Neoplasm
D- Degenerative or drugs
I- Iatrogenic or intoxication
C- Congenital
A-Autoimmune
T-Trauma
E-Endocrine
53
What is the mnemonic that we use to assess pain?
SOCRATES
54
What does SOCRATES stand for?
S-Site
O-Onset
C-Characteristics
R-Radiates
A-Association
T-Time course
E-Exacerbation/relieving factors
S-Severity
55
What are the 3 main vascular causes of chest pain?
~ Acute coronary syndrome
~ Pulmonary embolism
~ Acute aortic syndrome
56
What happens during aortic dissection?
There is a tear in the aorta from the tunica media to the tunica adventicia
57
What type of pain is an aortic dissection usually described as?
A tearing pain
58
Where might the pain radiate in an aortic dissection?
The back and sometimes in the abdomen too
59
How can we look to diagnose an aortic dissection?
~ Difference in BP in each limb
~ Widened media sternum seen on the chest x-ray
~ Aortic regurgitation (in type A)
60
How do we confirm an aortic dissection?
Contrast CT
61
How do we treat a type 1 aortic dissection?
Surgically
62
Where is a type 1 aortic dissection?
The ascending arch of the aorta
63
Where is a type 2 aortic dissection?
The descending limb or arch of the aorta
64
How do we treat a type 2 aortic dissection?
Medically
65
What's the most common drug used to treat a type 2 aortic dissection?
Labetalol
66
What are the 2 different types of infection that can cause chest pain?
~ Pericarditis
~ Myocarditis
67
What is an infection in the pericardium called?
Pericarditis
68
What is pericarditis?
Inflammation of the membrane surrounding the heart (pericardium)
69
Will you see a change in an ECG when the patient has pericarditis?
Yes, you will see ST elevation
70
Will the ST elevation in an ECG of a patient with pericarditis and myocarditis be the same as the ST elevation in an MI?
No, the ST elevation will be saddle shaped unlike in an MI
71
What chest sounds would you hear if the patient has pericarditis?
You would hear a high pitched scratching, which is the pericarditis friction rub
72
What is the first line treatment for pericarditis?
NSAIDs (unless elderly or GI problems)
73
What is myocarditis?
An infection of the heart causing inflammation in the myocardium
74
What usually makes chest pain worse when you have pericarditis?
Lying on your back or deep breathing
75
When will pain ease when a patient has pericarditis?
When they hold their breath
76
What is a common medical history of a patient with myocarditis?
A recent viral or bacteria infection
77
What different blood levels will a patient with myocarditis have?
Raised CRP, ESR and trops
78
What's a long term complication of myocarditis?
Chronic heart failure
79
What is costocondritis?
The inflammation and swelling of the cartilage between the rib and the breast bone
80
When is pain aggregated in costocondritis?
During deep breathing
81
Where can the pain radiate in costocondritis?
To the arm and shoulder
82
Where can pathologies be seen due to hypertension?
Heart, vessels, brain
83
What leads to left ventricular failure?
Long standing hypertrophy
84
What is the biggest cause of arteriosclerosis?
Atheroma
85
What causes an aneurysm?
Focal dilation of an artery which leads to an enlargement of the plaque
86
What replaces the muscle and elastic fibres, which causes an aneurysm?
Collagen
87
Is collagen capable of elastic recoil and contractions?
No
88
What does atheroma affect?
Large and medium sized vessels
89
Can you get atheroma in veins?
No, just high pressure vessels
90
Where does atheroma begin?
In the tunica intima
91
If atheroma progresses from the tunica intima where will it go?
Tunica media
92
How can we remember the risk factors of atheroma?
A- arterial hypertension
T- tobacco
H- hereditary
E- endocrine
R- reduced physical activity
O- obesity
M- male gender
A- age
93
What are the 4 stages of atheroma that can be seen by the naked eye?
~ Fatty streak
~ Lipid plaque
~ Fibrolipid plaque
~ Complicated atheroma
94
How do the blood lipids enter the intima in atheroma?
through the damaged endothelium
95
What are the two ways in which atheroma can be fatal?
Formation of plaque fissure and the development of a thrombosis
96
What's the definition of palpatation?
Unpleasant awareness of forceful, rapid or orregular beating of heart
97
How might palpitations be described?
Pounding, fluttering or flip-flopping
98
What is the time limit a to when we become really concerned about palpitation?
If they are lasting longer than 5 minutes
99
What is the heart doing during premature atrial complex and premature ventricular complex?
It is sorting out the problem itself and putting the heart back into the normal rhythm
100
What does AVNRT stand for?
Atrio ventricular node reentry tachycardia
101
What happens to the QRS complex during AVNRT?
They become narrowed and look very thin
102
Where is a P wave visible during AVNRT?
Immediately after the QRS complex
103
What is happening during AVNRT?
The AV node is working constantly as it has an additional pathway and so the constant loop of electrical activity causes the heart to beat faster
104
How can we manage AVNRT?
~ Vagal Manoeuvres
~ Adenosine
~Cardioversion
~ Catheter ablation
~ Beta blockers, calcium channel blockers
105
What does AVRT stand for?
Atrio ventricular reentry tachycardia
106
What is the most common example of an AVRT?
Wolff Parkinson White Syndrome?
107
What is the accessory pathway in WPW known as?
The bundle of Kent
108
What side of the heart is affected by type A WPW?
Left side
109
What side of the heart is affected by type B WPW?
Right side
110
What is a clear indication on an ECG that a person is suffering from WPW syndrome?
Delta wave presence
111
What are the two types of life threatening tachycardias?
Ventricular tachycardia and ventricular fibrillation
112
What are the two types of VT?
Focal VT and Re-entant VT
113
What is the problem during Focal VT?
The cells become irritated and they begin to over fire
114
What is the problem during Re-entrant VT?
There is scaring on the heart tissue and this causes electrical loop abnormalities
115
What causes ventricular fibrillation?
Prolonged ventricular tachycardia
116
Why is ventricular fibrillation so dangerous?
Because you have very small blood flow, if any to the body
117
What are the 5 things that you must do when you are assessing a patient who is presenting with palpitations?
1. Take a history
2. Physical exam
3. 12 lead ECG
4. Lab tests
5. Further monitoring
118
What investigative tests should you carry out when you have a patient presenting with palpitations?
12 lead ECG
ECHO
Blood tests including FBC, U and Es, TFT (thyroid function test) and CRP
119
What is the first thing you should doo when you are presented with a patient that has palpitations?
Carry out your ABCDE approach
120
What are the two different classes of heart failure?
~Chronic or acute
~Preserved or reduced ejection fraction
121
When you are in heart failure what is your body doing to try and help the issue that is occuring?
The body tries to compensate to try and retain cardiac output
122
What is classified as a reduced ejection fraction?
Less than 35%
123
How would you describe acute heart failure?
The sudden inability of the heart to maintain an adequate cardiac output and blood pressure
