cardiogenic pulmonary oedema

Question 1

what is the most common cause of CPO

Answer 1

LSHF

Question 2

what happens in left sided heart failure that leads to CPO

Answer 2

LV becomes unhealthy and it can’t pump effectively, blood backs up in the pulmonary veins and capillaries

increased pulmonary pressure leadings to fluid from the interstitum pushing into the lungs

Question 3

why dose severe HTN lead to CPO

Answer 3

LV cannot overcome the force required due to high after load

Question 4

what is heart failure

Answer 4

inability of the heart to pump blood/ supply enough blood

Question 5

what are the two types of heart failure

Answer 5

systolic were the ventricles can’t pump hard enough during systole

and diastolic, where not enough blood fills into the ventricles during diastole

Question 6

how dose heart failure lead to arrhythmia

Answer 6

muscle wall becomes thins or thickens

heart cell irritation or ishcemia

arrhythmia

Question 7

Guideline treatment of CPO

Answer 7

Acquire a 12 lead ECG.

Administer 0.8 mg of GTN SL.
Continue to administer 0.8 mg GTN SL every five minutes as above if the patient is not improving. Increase the dosing interval to ten minutes if caution is required.

Apply CPAP if the patient has moderate to severe respiratory distress that is not rapidly improving (see the ‘CPAP’ section). If backup for CPAP is unavailable or delayed, apply PEEP.

Commence a GTN infusion IV if the patient is not rapidly improving.

Fentanyl in 10-20 mcg doses IV or morphine in 1-2 mg doses IV may be administered every five minutes as required for severe anxiety.

Question 8

role of GTN in CPO

Answer 8

reduces preload and after load, off loading some strain from the heart, thus reducing the volume and ejection force required for the heart to pump

Question 9

role of CPAP

Answer 9

decreased WOB and increased cardiac output by provoking a constant trend of positive pressure treating alveolar collapse

Question 10

usual presentation of CPO

Answer 10

generally in elderly, with ischemic heart disease, HTN, diabetes

usually breathless, sweaty, agitated, tachy, hypoxic, HTN

Question 11

what is negative pressure pulmonary oedema

Answer 11

during any form of asphyxiation, negative pressure can develop in the thoracic cavity as a result of inspiratory effort against a closed airway

Question 12

common mistakes with CPO

Answer 12

mistaking COPD for CPO

pneumonia for CPO

fail to identify route cause e.g. STEMI

Question 13

how to treat negative pressure pulmonary oedema

Answer 13

do not go down CPO pathway, no CPAP or GTN, treat hypoxia

Question 14

how to treat a CPO who is on a long acting vasodilator

Answer 14

reduce GTN dose to 0.4 mg and increase dose interval to 10 mins, prioritise CPAP