Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

NURS3032 - NC5 Critical Care > Circulation > Flashcards

Circulation Flashcards

1
Q

Atherosclerosis

A

The build up of plaque (fats/cholesterol) in and on artery walls leading to atheroma (hardening) and stenosis (narrowing). Increases SVR leading to hypertension and contributes to PAD/PVD. Increases risk of thrombosis/occlusion leading to PE, MI or CVA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Hypertensive Crisis

A

A sudden, severe and persistent increase in blood pressure involving damage to vessels, tissues and organs due to elevated pressures.
SBP = 180+ OR DBP = 110+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Cardiac Cycle

A

Atrial diastole (S to p wave)- heart muscles relax and valves closed; systemic blood returns to atria.
Atrial systole (p to R wave) - atrial contraction and AV valves open; blood flows to ventricles.
Ventricular systole (S to T wave) - ventricular contraction and semilunar valves open; blood passes to aorta/pulmonary arteries
Ventricular diastole (T to S wave) - heart muscles relax and valves closed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Cardiac Conduction System

A

Network of specialised cardiac cells (myocytes) and nerves that transmit electrical impulses to initiate contraction of the heart muscle, thereby controlling the rate and rhythm of heartbeats.

SA node initiates depolarisation > atrial contraction > slow conduction of excitation signal through AV node (allow for atrial emptying) > rapid conduction through bundle of His to Purkinje fibres > ventricular contraction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

SA Node

A

Cluster of specialised cardiac cells located in upper R) atrium that generates electrical impulses to stimulate atrial contraction, thereby initiating and pacing heartbeats.
Controlled by autonomic nervous system (para/sympathetic) which releases hormones (nor/adrenaline) based on activity and stress.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

AV Node

A

Cluster of specialised cardiac cells and nerves located in triangle of Koch. Delays the electrical signal from SA node by consistent amount of time before transmitting to Purkinje fibres.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Bundle of His (AV Bundle)

A

Branch of nerve fibres extending from AV node to L) and R) ventricles, located along inter-ventricular septum. Transmit electrical signal to Purkinje fibres.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Purkinje Fibres

A

Nerve fibres located on subendocardial surface of ventricle walls. Transmit rapid electrical signals to L) and R) ventricles to stimulate contraction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Cardiac Output

A

The amount of blood the heart pumps through circulatory system in 60sec.
CO = HR X SV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Stroke Volume

A

The volume of blood ejected by the LV during each systolic contraction.
SV = EDV - ESV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Preload

A

The stretch of the ventricular myocardium (volume) BEFORE systole.
Preload = EDV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Afterload

A

The pressure the heart must work against to eject blood during ventricular systole.
Afterload <–> MAP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Contractility

A

The force of contraction of the heart muscle. Proportional to the initial length of the muscle fibre (i.e. greater stretch = greater contractility)
Increased contractility = increased SV and decreased ESV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Central Venous Pressure

A

The pressure of blood within the right side of the heart (vena cava and R) atria)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Ejection Fraction

A

The percentage of the total volume of blood in the heart that is pumped out with each contraction. Normal EF is 50+%.
EF = (SV/EDV) X 100

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

End Diastolic Volume

A

The volume of blood in the ventricles BEFORE systole.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Systemic Vascular Resistance

A

The opposition to systemic blood flow as a result of friction between blood cells/proteins and vessel walls.
SVR <–> MAP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

End Systolic Volume

A

The volume of blood remaining in the ventricles AFTER systole.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

MAP

A

Mean arterial pressure.
MAP = CO X SVR.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Vasopressors

A

Vasoconstriction > increased SVR > increased MAP > increased systemic perfusion.
Phenylephrine, norepinephrine, epinephrine, and vasopressin.
Dopamine is dose-dependent vasopressor/inotropic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Percutaneous Coronary Intervention

A

Insertion of catheter and balloon into coronary arteries (via femoral/inguinal) to dilate vessels (compress) plaque and place stent to maintain patency.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Thrombolytic/Fibrinolytic Therapy

A

IV administration of thrombolytic agents to dissolve existing clots - e.g. alteplase, reteplase, tenecteplase.
Must be administered within 30min of arrival.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

THROMBINS2

A

Initial management of patient with chest pain and suspected ACS (MI).

Thienopyridines - clopidogrel, prasugrel - antiplatelets.
Heparin/enoxaparin - anticoagulant.
Renin-angiotensin blockers (ACEIs/ARBs) - antihypertensive
Oxygen - titrated to SpO2 (avoid excess > incr. coronary resistance)
Morphine/fentanyl - PRN analgesia and anxiolysis
Beta-blockers - antihypertensive and reduce HR.
Invasive procedures - PCI.
Nitroglycerin (GTN) - vasodilation.
Statins
Salicylate (aspirin 300mg) - ROUTINE antiplatelet.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Transcutaneous Pacing

A

Temporary non-invasive method of cardiac pacing in conscious patients with symptomatic bradycardia or heart block. Delivers synchronised ventricular stimulation via transcutaneous patches.
Aim to stabilise haemodynamics until underlying problem can be treated.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Pacemaker

A

Medical device composed of pulse generator and leads/electrodes implanted in the heart. Delivers controlled electrical stimuli to the heart muscle to regulate rhythm. May be temporary or permanent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Cardioversion

A

Planned procedures to treat arrythmias (e.g. Afib, AFl).
Electrical - delivery of controlled (100-300j) electrical shocks via electrodes placed on chest that are synchronised with QRS complex.
Chemical - use of anti-arrhythmic medications

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Defibrillation

A

Emergency procedure to treat life-threatening arrhythmias or pulseless cardiac arrest. Manual or automated delivery of unsynchronised powerful (200-300j) electrical shock via electrode pads to depolarise heart cells and disrupt the arrhythmia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Catheter Ablation

A

Minimally-invasive procedure involving insertion of catheter into heart via blood vessels to destroy small areas of tissue using radiofrequency energy to prevent tachy-arrhythmias (e.g. SVT, VT).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

CABG

A

Surgery to restore blood flow in coronary arteries. Attachment of healthy blood vessel (from chest/leg) below blockage to reroute blood flow to muscle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Non-Invasive Haemodynamic Monitoring
Definition
Types

A

Haemodynamic monitoring that does NOT require insertion of any device into the body.
1. Non-invasive blood pressure (sphygmomanometer)
2. 12-lead Electrocardiogram (ECG)
3. Echocardiogram (ultrasound)
4. Pulse oximetry - SpO2, PR.

31
Q

Haemodynamic Monitoring
Definition
Types

A

Study of movement and forces of blood within cardiovascular system.
1. Invasive vs non-invasive
2. Continuous vs intermittent

32
Q

Invasive Haemodynamic Monitoring
Definition
Types

A

Haemodynamic monitoring requiring cannulation of vascular system to accurately measure pressure or flow in real time.
1. Arterial lines
2. Central venous catheters
3. Transoesophageal echocardiography
4. Pulmonary artery catheter

33
Q

Arterial Lines
Definition
Pros/cons

A

Continuous monitoring of arterial blood pressure via catheter inserted into radial or femoral artery.
Pros - continuous, sensitive, repeat ABGs.
Cons - expensive, complex, risk of complications, requires expertise.

34
Q

Arterial Lines
Indications
Complications

A

Indications:
1. Critical illness and/or unstable BP - e.g. trauma, high-risk surgery, shock.
2. IV vasoactive agents - e.g. vasopressors/inotropes.
3. Mechanical ventilation

Complications - bleeding, infection, peripheral ischemia, embolism, aneurysm.

35
Q

Arterial Lines
Management

A
  1. Infection control
  2. Labelling
  3. Aseptic dressing
  4. Continuous monitoring - bleeding, distal perfusion, phlebitis/infection.
  5. Ensure sufficient flush volume and pressure in system - >250ml saline, >300mmHg.
  6. Levelling and zeroing- air-fluid interface levelled to mid-axillary line; re-zero transducer.
  7. Waveform monitoring
36
Q

Central Venous Catheters
Definition
Uses

A

Catheter inserted into internal jugular, femoral or subclavian veins and advanced into inferior/superior vena cava or right atrium.
1. Establish venous access during circulatory collapse
2. Administer prolonged IV therapy or irritating agents
3. Measure CVP
4. Perform haemodialysis

37
Q

Pulmonary Artery Catheter
Definition
Uses

A

Catheter inserted through major vein and advanced through right heart into pulmonary artery and wedged in pulmonary vessel via balloon inflation.
Used to monitor:
1. Central temperature
2. Pulmonary artery pressure
3. RA/RV pressure
4. Venous saturations
5. Left-sided diastolic filling

38
Q

Transoesophageal Echocardiography
Definition
Uses

A

Flexible telescope with ultrasound scanner inserted via oeseophagus to provide images of the heart.
Used to assess:
1. Regional wall motion and ischaemic changes
2. Ventricular function
3. Valvular function
4. Intra-cardiac air or masses

39
Q

ECG
Definition

A

Electrocardiograph using 12 leads and 10 electrodes to generate a 3D map of electrical activity in the heart.

40
Q

ECG
Electrode Placement

A

PRECORDIAL ELECTRODES:
V1: 4th ICS RIGHT sternal margin
V2: 4th ICS LEFT sternal margin
V3: midway between V2-V4
V4: 5th ICS, mid-clavicular
V5: 5th ICS, midway between V4-V6.
V6: 5th ICS, mid-axillary line (same level as V4)

LIMB ELECTRODES:
RA - right arm
LA - left arm
RL - right leg
LL - left leg

41
Q

ECG
Limb Leads

A

Lead I - RA to LA.
Lead II - RA to LL.
Lead III - LA to LL
Lead aVR - LA to LL x RA.
Lead aVL - RA to LL x LA
Lead aVF - RA to LA x LL

42
Q

Einthoven’s Triangle

A

The 3D image of the heart created by the triangular cross-section of planes generated by the 6 limb leads - I, II, III, AVR, AVL and AVF.

43
Q

ECG
Lead Images

A

II, III, and aVF - inferior surface of the heart
V1 to V4 - anterior surface
I, aVL, V5, and V6 - lateral surface
V1 and aVR - right atrium and cavity of left ventricle

44
Q

p Wave

A

ATRIAL DEPOLARISATION (discharge of SA node) Atrial systole (contraction) occurs from peak of p-wave to R wave.
Normal p-wave is < 0.12sec (3 small sq.)

45
Q

Pathologic Q waves

A

Q waves that are:
> 40 ms (1 mm) wide
> 2 mm deep
> 25% of depth of QRS complex
Indicating current or prior MI.

46
Q

ST elevation

A

Indicates infarction (OR pericarditis).

47
Q

PR Interval

A

Atria to ventricular conduction time via His bundle.
Normal PR interval is 0.12-0.2sec.

48
Q

Prolonged PR interval

A

AV Block.
1st degree > 0.2sec
2nd degree (T1) - increasing PR interval.
2nd degree (T2) - constant prolonged PR interval.
3rd degree - p-waves and QRS dissociated.

49
Q

ST depression

A

Indicates ischaemia.

50
Q

QRS Complex

A

VENTRICULAR DEPOLARISATION. Ventricular systole (contraction) occurs from S to T wave.
Normal QRS 0.08-0.12 sec (2-3 small sq.)

51
Q

T Wave

A

VENTRICULAR REPOLARISATION. Ventricular diastole occurs from peak of T wave to S wave.

52
Q

U Wave

A

Upright wave following T wave. Represents late-phase ventricular repolarisation. Indicates hypokalaemia.

53
Q

Cardiac Arrythmia
Definition
Types

A

Group of conditions in which the heart beat is irregular and/or too fast or slow, due to dysfunction of the electrical conduction system.
1. Extra beats - e.g. PVC.
2. Supra-ventricular tachycardias - e.g. AFib, AFl.
3. Ventricular arrhythmias - e.g. VT, VFib.
4. Bradyarrhythmias

54
Q

Troponin

A

Protein present only in cardiac muscle (NOT skeletal muscle). Damage to cardiac cells results in progressive release of troponin into bloodstream over 4-12 hours following symptoms.

TnI - 0-0.04ng/ml (elevated within 4 hours)
TnT - 0 -0.01 ng/ml (more-specific and detects smaller damage)

55
Q

Antihypertensive Agents

A

Beta-blockers - e.g. atenolol, metoprolol.
Calcium channel blockers - e.g. amlodipine, verapamil.
ACEIs/ARBs - e.g. benazapril, enalapril.
Diuretics - e.g. furosemide.

56
Q

Anticoagulant Agents

A

Unfractionated Heparin
DOACs (direct thrombin/factor Xa inhibitors) - e.g. dabigatran, apixaban, rivaroxaban.
LMWH - e.g. enoxaparin
Warfarin (vitamin K antagonist)

57
Q

Anti-platelet Agents

A

Aspirin
Clopidogrel
Ticagrelor

58
Q

Anti-arrhythmic Agents

A

Negative inotropes:
1. Rate-controllers (negative inotropes) - BBs/CCBs
2. Rhythm-controllers - sodium/potassium channel blockers - e.g. amiodarone, lidocaine.

Other - atropine

59
Q

Fibrinolytic Agents

A

Alteplase
Streptokinase
Tenecteplase

60
Q

Perfusion

A

The process and adequacy of the delivery of oxygen via the circulatory system to organs/tissues to enable normal cellular/metabolic function.

61
Q

Atrial Diastole

A

Atrial relaxation and passive filling with blood from vena cavae. AV valves closed.
Approx. 0.7 sec

62
Q

Atrial Systole

A

Atrial contraction and ejection of blood into ventricles. AV valves open. Aortic/pulmonic valves closed.
Approx. 0.1 sec.

63
Q

Ventricular Diastole

A

Commences before atrial systole. Ventricular relaxation and passive filling with blood from atria. AV valves open. Aortic/pulmonic valves closed.
Approx 0.5 sec.

64
Q

Ventricular Systole

A

Ventricular contraction and ejection of blood into pulmonary artery and aorta. AV valves closed. Aortic/Pulmonic valves open.
Approx. 0.3sec

65
Q

Positive Inotropes

A

Increased cardiac contractility > increased CO > maintains MAP > maintains systemic perfusion
E.g. epinephrine, norepinephrine, dobutamine, digoxin and milrinone.
Dopamine is dose-dependent vasopressor/inotropic.

66
Q

Negative Inotropes

A

Decrease cardiac contractility and heart rate to treat hypertension and/or arrythmia.
E.g. beta-blockers, calcium-channel blockers, amiodarone, lidocaine.

67
Q

4 A’s of Arrythmia

A

Atropine - bradyarrythmia
Adenosine - SVT
Adrenaline - asystole/PEA
Amiodarone - VT, VF, AFib

68
Q

ECG Interpretation

A
  1. Is there any electrical activity?
  2. What is the QRS rate (is this normal)?
  3. What is the QRS interval? (0.08-0.1sec)
  4. Is the QRS rate regular or irregular?
  5. Is atrial activity present? (p-waves)?
  6. What is the atrial rate (is this normal)?
  7. What is the relationship between atrial and ventricle activity?
    * What is the PR interval? (<0.2sec).
    * How many p-waves for each QRS complex?
69
Q

MET Criteria

A

Cardiac arrest
PR = </=40 OR >/=140bpm
SBP = <90mmHg
*Oliguria/Anuria

70
Q

Full Blood Count (FBC)
RBC
WBC
Platelets
Hb

A

RBC - 4.0-5.9 (male) OR 3.8-5.2 (female) x 10(12)/L
WBC - 4.5-11 x 10(9)/L
Platelet - 150-450K/mcL
Hb - 14-18 (male) OR 12-16 (female) g/dl

71
Q

Urea/Electrolytes
Sodium
Calcium
Phosphate
Potassium
Creatinine
Urea

A

Sodium - 135-145 mEq/L
Calcium - 2.2-2.7 mmol/L (8.5-10.5mg/dl)
Phosphate - 1.12-1.45 mmol/L (3.4-4.5 mg/dl)
Potassium - 3.5-5.5 mEq/L
Creatinine 0.7-1.3 (male) OR 0.6-1.1 (female) mg/dl
Urea - 1.8-7.1mmol/L (5-10 mg/dl)

72
Q

Abnormal T waves
High-voltage
Low-voltage + U waves
Low-voltage + ST depression
Inverted

A

High-voltage - hyperkalemia.
Low voltage + u waves - hypokalaemia.
Low voltage + ST depression - heart disease.
Inverted - coronary ischemia.

73
Q

High-voltage p-waves

A

Atrial hypertrophy.

74
Q
A

NURS3032 - NC5 Critical Care (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions