Acute Coronary Syndrome / Circulatory system general Flashcards
1
Q
What is a pulse
A
Expansion and recoil of artery walls in response to the pressure of the blood travelling round the circulatory system, that occurs following each contraction of the left ventricle.
2
Q
Normal heart rate value. Female and male HR values.
A
60-100bpm. Females 72-80bpm > males 64-72bpm.
3
Q
Definition of tachycardia
A
High/fast HR of >100bpm
4
Q
Definition of bradycardia
A
Low/slow HR of <60bpm.
5
Q
pH value for acidaemia
A
<7.35
6
Q
Causes of academia
A
Overproduction of metabolic acids in diabetic ketoacidosis
Carbon dioxide retention leading to respiratory acidosis
Retention of metabolic acids due to AKI
7
Q
pH value for alkalosis
A
> 7.45
8
Q
Causes of bradycardia
A
Increased vagal activity Athletic heart Cardiac conduction defects Raised ICP Drugs eg beta blockers, calcium channel blockers
9
Q
General causes of tachycardia
A
Exercise Pain/ anxiety Pyrexia Cardiac arrhythmias Compensation for low BP due to hypovalaemia, MI, left ventricular failure Chonotropic drugs Inotropic drugs
10
Q
Normotensive BP definition
A
BP within normal range 60-100/40-90mmHg
11
Q
Hypotension definition
A
BP <100mmHg
12
Q
General causes of hypotension
A
Myocardial disfunction Low ICP Antihypertensive medication Heart failure Acute coronary syndrome Physiological shock Haemorrhage
13
Q
Hypertension (sys value)
A
Sustained, elevated arterial systolic BP of >140mmHg
14
Q
Ways to assess organ perfusion
A
Urine output- kidney perfusion Stool output- small and large bowel perfusion Level of consciousness- brain perfusion Chest pain- heart perfusion Nausea- stomach and intestine perfusion
15
Q
Examples of central pulses
A
Carotid artery
Femoral artery
16
Q
Examples of peripheral pulses
A
Radial artery (wrist) Brachial artery (elbow)
17
Q
Definition and function of blood pressure
A
Pressure exerted by the blood against the inner walls of the vessels containing it. Responsible for maintaining blood circulation between heartbeats.
18
Q
Cause/equation for blood pressure
A
BP=COxSVR
19
Q
Definition of systolic blood pressure
A
Pressure in the arteries when the left ventricle is fully contracted.
20
Q
What 3 things determine/are reflected into systolic BP?
A
Force of ventricular contraction.
Degree of systemic vascular resistance.
Compliance of the arteries.
21
Q
Definition of diastolic blood pressure
A
Pressure exerted on the arteries when the left ventricle is relaxed in diastole.
22
Q
What 3 things determine/are reflected in diastolic BP?
A
Velocity of the run off blood from the aorta.
Elasticity of arterial walls.
Degree of vasoconstriction.
23
Q
Definition of pulse pressure and normal value
A
Difference between the systolic and diastolic pressures usually 35-45mmHg
24
Q
Narrowing of pulse pressure is an indication of…
A
Reduced CO which may be covered by compensatory mechanisms such as vasoconstriction to increase SVR.
25
Primary hypertension definition
Underlying cause if hypertension, often lifestyle factors, such as obesity, physical inactivity, high salt intake, stress or hereditary
26
Secondary hypertension definition
Acute anatomical or physiological conditions such as raised ICP, adrenal/renal/aortic disease
27
Mean arterial blood pressure calculation
1/3 systolic BP + 2/3 diastolic BP
28
Cholesterol normal values
3.0-5.0mmol/L
29
Common abnormalities prior to cardiac arrest
```
Hypoxaemia
Increased RR
Hypotension
Hypoperfusion
Metabolic acidosis
Metabolic acidosis
Tissue hypoxia
```
30
In a hypokalaemic pt which method and how fast would you replace potassium?
IV potassium over 2hrs, when <2.5mEq/L, reassessment, continuous ECG monitoring and repeat serum potassium levels
31
In acidosis pt would bicarbonate stores be high or low? And why?
Low after stores used up to compensate for low pH
32
What is a hypertensive crisis?
Increased, sudden surge in diastolic BP
| BP of 180/120
33
What is the treatment for hypertensive crisis?
Prescription and administration of calcium channel blockers, beta blockers, ACE inhibitors
34
What is agonal breathing and when does it occur?
Agonal breathing occurs following an miocardial infarction (MI) where the pt appears to be breathing but gaseous exchange isn’t actually occurring.
35
Definition of CO
Volume of blood ejected from the left ventricle per minute
36
What is the equation for cardiac output (CO)/what two factors directly influence CO?
CO= HRx SV
37
What is the normal volume for CO?
4-8L/min
38
What is the average volume for CO at rest?
5.25L (75bpmx70ml)
39
Which nervous system (ANS/CNS) controls HR?
Autonomic
40
What stimulates the sympathetic nervous system in terms of circulation?
Fall in BP, HR, CO, SV
41
What effect does sympathetic nervous stimulation have on HR?
Increased HR, atrioventricular conduction and myocardial contractility.
42
What causes stimulation of the parasympathetic nervous system in terms of circulation?
Increase in HR, BP, CO, SV
43
What effect does parasympathetic nervous stimulation have on HR?
Decreased HR and atrioventricular conduction with NO effect on myocardial contractility.
44
What 4 factors effect stroke volume?
Preload
Afterload
Contractility
Distensibility
45
What is the definition of preload?
Volume of blood in the ventricle following diastole
46
What is the definition of afterload?
Resistance against which the ventricle must eject blood volume = BP
47
What is the definition of contractility?
Myocardial contractile strength which enables complete ventricular emptying
48
What is the definition of distensibility?
Myocardial relaxation which enables complete ventricular filling
49
What 6 things determine BP?
```
Cardiac output.
Circulating blood volume.
Systemic vascular resistance.
Venous return.
Elasticity of arterial walls.
Viscosity of the blood.
```
50
What are the two most important mechanisms controlling blood volume?
Fluid intake and urine output.
53
In response to decrease in BP, what do impulses sent from the cardiac vasomotor centre to the sympathetic nervous system stimulate do to compensate?
(Which chemical, which receptor, locations of receptor, effect of chemical release from each location)
Noradrenaline.
Released from beta 1 receptors.
Located in the sinus node, atrioventricular node, myocardium and atrial walls.
Sinus node- increase in HR.
AV node- increase impulse conduction from atria to ventricles.
Myocardium- increase force of contractions.
Atrial walls- vasoconstriction, increasing systemic vascular resistance and thus BP.
54
What are catecholamines? Where are they released from? What are some examples? Why are they released?
Hormones produced by the adrenal glands located above the kidney.
Such as dopamine, adrenaline, nor adrenaline.
Released in times of physical or emotional stress.
55
What do catecholamines stimulate in the liver? And what does this result in?
The conversion of glycogen to glucose resulting in hyperglycaemia.
56
Where in the brain are osmoreceptors located?
Hypothalamus
57
Due to compensatory mechanisms, how many mls of blood loss can occur whilst a normal BP is maintained?
1500mls
58
What percentage of blood volume is lost at the point that progressive shock begins?
30-40%
59
What is the name for the receptors that detect decrease in BP? And where are they located?
Baroreceptors in the aortic arch and carotid sinus detect a decrease in BP.
60
Where is the cardiac vasomotor centre located in the brain? What is it responsible for?
Located in the medulla oblongata.
| Responsible for accelerating/inhibiting heart beat.
61
What does CVP reflect?
The pressure of the blood within the right atrium of the heart. Usually reflects the venous return/ preload.
62
Which enzyme is looked for in blood tests to indicate a MI?
Troponin.
63
What is the average volume of circulating blood?
5 L
64
What do altered levels of calcium, sodium, potassium and magnesium effect the contraction of?
Myocardium and smooth muscle.
65
Elevated potassium levels is known as?
Hyperkalaemia
66
What do elevated potassium levels or low calcium levels result in?
Cardiac dysarrhythmias.
67
Where is the bicuspid/mitrial valve located?
Between the left atrium and ventricle
68
Where is the tricuspid valve located?
Between the right atrium and ventricle
69
What are the 3 cardiac disorders that fall under the classification of ACS/CHD?
Stable angina
Unstable angina
Myocardial infarction
70
What are the 6 types of cardiac disorder?
```
ACS
Valve disease
Electrical disorders
Cardiomyopathy
Coronary heart disease
Heart failure
```
71
What are the two types of heart failure?
Left ventricular failure
| Congestive cardiac failure
72
What are the 7 stages of angina?
```
Atherosclerotic narrowing
Plaque rupture
Platelet aggregation aka white clot
Partial occlusion
Restriction of blood and O2 supply
Ischaemic myocardium
Pain on exertion continuing into rest
```
73
What is angina also known as? (general term)
Ischaemia
74
In terms of pain, what is a symptom indicative of angina?
Pain on exertion and rest
75
What are the 8 stages of MI?
```
Atherosclerotic narrowing
Plaque rupture
Platelet aggregation
Thrombus formation aka red clot
Total occlusion
Ischaemic myocardium
Injured myocardium
Infarcted myocardium
```
76
What are the differences in the mechanism of damage between MI and angina?
MI results in infarcted myocardium; angina ischaemic myocardium
MI results in thrombus formation (red clot); angina results in platelet aggregation (white clot)
MI results in total occlusion; angina results in partial occlusion
77
What do both angina and MI start from?
An atherosclerotic narrowing and plaque rupture
78
What are 8 modifiable risk factors for CHD?
```
Smoking
High lipid profile (high LDL, low HDL)
Physical activity
Obesity
Hypertension
Stress
Diabetes mellitus
Insulin resistance/ metabolic syndrome
```
79
What are 4 examples of non-modifiable risk factors for CHD?
Age
Male in gender
Ethnicity
Genetic
80
What is the definition of acute coronary syndrome?
All conditions caused by sudden impairment of blood flow in a coronary artery leading to ischaemia/infarction of myocardium
81
What are the 3 ACSs that can result from stable angina?
Unstable angina
Non ST elevation MI (NSTEMI)
ST elevation MI (STEMI)
82
3 criteria indicating stable angina? (pain, ECG, troponin)
Pain on exertion
?ECG changes on exercise tolerance test
-ve troponin
83
3 criteria indicating unstable angina? (pain, ECG, troponin)
Pain on rest
?ECG changes
-ve troponin
84
3 criteria indicating NSTEMI? (pain, ECG, troponin)
?Pain
ECG changes
+ve troponin
85
3 criteria indicating STEMI? (pain, ECG, troponin)
?Pain
ECG changes
+troponin
86
What are 8 associated symptoms of ACS?
```
Breathless ?rest/exertion
Nausea/vomiting
Sweating, pale, cold, clammy
Restless
Palpitations
Syncope
Oedema
Cyanosis
```
87
What is the assessment tool used to assess chest pain in ACS?
SOCRATES
88
What does SOCRATES stand for?
```
Site
Onset
Character
Radiation
Associated symptoms
Time
Exacerbation
Severity
```
89
What are the letters of the ECG wave complex
PQRST
90
What is the chemical marker for ACS?
Troponin
91
What is the main interventions for ACS?
```
Asprin- anti-platelet
Nitrate- vasodilator
Opiate- pain relief
IV antiemetic
Bed rest
High flow O2 therapy
Reassurance
```
92
What is the surgical intervention for STEMI?
Primary Coronary Intervention
93
When should troponin blood tests be taken?
At 2 hrs and 12 hrs post ACS.
94
What does +ve troponin indicate?
NSTEMI
95
What does -ve troponin indicate?
?unstable angina
| PMHX
96
What is the indicator of a diagnosis of stable angina?
| What action should be taken?
Troponin T of <0.1.
| Discharge or conduct exercise tolerance test
97
What is an indicator of unstable angina?
Troponin T <0.1
98
What is an indicator of NSTEMI?
Troponin T>1.5
99
What is an indicator of STEMI?
Troponin T>1.5
100
What is involved in the preparation for PCI?
```
Antiplatelet
Subcutaneous low molecular weight heparin
NBM
Shave groin
Name bands, informed consent
```
101
What is primary coronary intervention?
Angioplasty followed by advancement of a arterial catheter to site of block to insert a stent
102
Following primary coronary intervention what is involved in nursing care?
```
Bed rest
Nurse at 45 degree angle
12 ECG with pain
Interarterial BP
4hrly obs
Fluid balance chart
```
103
What is the nursing care following primary coronary intervention using radial approach?
Remove T band at 2 hrs
| Check pulse, BP, pedal pulse and puncture site every 30 minutes for 4 hours
104
What is the nursing care following primary coronary intervention using femoral approach?
At 4 hours remove arterial sheath
Nurse flat
Check pulse, BP, pedal pulse every 30 mins for 4 hours or until stable
105
What are the possible ongoing complications of ACS?
```
On going chest pain
Arrythmias
Conduction defects
Cardiac failure
Bleeding
Hospital acquired infection
Urinary retention
```
