APO

Question 1

Define APO

Answer 1

Sudden accumulation of serous Transexudate into the interstitial space between the capillaries and the alveoli, Bronchioles and bronchi

Question 2

Describe the reasons for left ventricular failure

Answer 2

AMI
Cardiomyopathy 
ACS
Hypertension 
Valvular disease

Question 3

What compensatory mechanisms arise as a result of left ventricular failure

Answer 3

• starlings regulation
• sympathetics
• ventricular remodelling
• Renal Compensation
• Atrial Natriuretic peptide

Question 4

Describe the fluid movement in the alveoli under normal pressures

Answer 4

Normal pressure
Artery side - hydrostatic pressure forces fluid out of the capillaries into the interstitial space

Vein side - colloid osmotic pressure forces fluid back into the capillary

Question 5

Describe fluid movement in lungs with APO

Answer 5

Extra pressure build up leads to increased hydrostatic pressure forcing more fluid into interstitial space

Colour osmotic pressure is not enough to force fluid back into capillaries therefore fluid fills alveoli and gas exchange is compromised

Question 6

Describe the vicious cycle of APO

Answer 6

Increased hydrostatic pressure - fluid accumulation in alveoli

Reduced gas exchange = hypoxia ^ Work of breathing

Increased Catecholamine release and renin, angiotensin, aldosterone activation

Increased systemic vascular resistance
Increased preload and afterload
Increased cardiac work and O2 demand

Decreased Ventricular emptying, relaxation
decreased cardiac output

Increased end diastolic volume/pressure
Increased LA pressure
Increased pulmonary vascular pressure

Question 7

Patient presentation of APO

Answer 7

Cardiovascular

• increase hr
• arrhythmias
• orthostatic hypotension
• decreased peripheral pulses
• pale/cyanosic, cool clammy

Respiratory

• dyspnoea on exertion
• orthopnoea (sob on lying down)
• tachypnoea
• dry cough
• adventitious sounds (crackles, wheezes, decreased breath sounds)

subclavian retraction
V/Q mismatch

Question 8

Ddx for APO

Answer 8

• acute episode of COPD or asthma
• acute pneumonia
• pulmonary embolism
• arrythmia

Question 9

Patient management APO

Answer 9

- GTN 
rest and recovery 
Posture 
Oxygen
cpap 
Diuretics 
Opiates 

IV access
12 Lead ecg

Question 10

Describe a diuretic drug

Answer 10

Frusemide

Question 11

Describe starlings regulation

When does it happen?

Answer 11

Pooling if blood in the LV increased LVEDP leading to lengthening of myocardial fibres

• resulting in
  Increased inotropy, preload, SV, myocardial oxygen consumption

APO mechanism

Question 12

Describe sympathetic regulation

Answer 12

Detected by baroreceptors

• increased force of contraction (inc. sympathetic tone)
• inc. catecholamine release
• tachycardia, vasoconstriction, redistribution of blood

APO mechanism

Question 13

Describe ventricular remodeling

Answer 13

Changes to structure (muscle mass) and function (impaired systolic function)

Injury to the myocardium > hypertrophy

APO mechanism

Question 14

Describe Renal Compensation

When it’s seen?

Answer 14

APO mechanism

Activation of
Renin - angiotensin - aldosterone RAA system

Decreased Renal blood flow > sodium and water retention

Angiotensin - peripheral vasoconstriction
Aldosterone > promotes sodium retention, SNS activation, baroreceptor dysfunction > stretch ventricle walls (good) but leads to neg outcome

Question 15

Atrial Natriuretuc Peptide describe

Answer 15

Potent diuretic
Release from Syria in response to stretch

Inhibit
RAA system
Sympathetic ns system