The Circulation System		2

Donating Blood and Aircrew

Many aircrew express the wish to donate blood either in support of the National Blood Transfusion Service or for personal reasons. In order to prevent the very slight risk of post transfusion faintness (syncope) it is recommended that, having given blood, aircrew should drink plenty of fluids and rest supine for a short time (15 - 20 minutes). They must refrain from flying duties for a minimum of 24 hours. It is also advisable to seek advice from an aviation specialist prior to blood donation.

Pulmonary Embolism

The blood supply to the lungs may be interrupted by a blockage to the Pulmonary artery. This not only causes death of lung tissue but also prevents oxygenation of the blood. The most common cause of this condition is known as a pulmonary embolism which results from a blood clot from the leg (thrombus) becoming detached and travelling to the lungs where it becomes lodged causing the blockage.

The immobility associated with long haul flights may predispose the formation of blood clots in the lower limbs. Exercising the legs help reduce the risk and both crews and passenger should be encouraged to walk around the cabin from time to time throughout the flight.

The Circulation System 2

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2 Questions

Questions 2

Questions

1.How is oxygen transported around the body?

a.By red blood cells combined with carbon dioxide

b.By red blood cells combined with nitrogen and water vapour

c.By red blood cells combined with haemoglobin

d.By red blood cells combined with nitrogen, hormones and plasma

2.How is the rate and depth of breathing controlled?

a.By the amount of oxyhaemoglobin in the blood and lungs

b.By the amount of haemoglobin in the blood and the lungs

c.By the amount of carbon monoxide and oxygen in the blood

d.By the amount of carbonic acid in the blood

3.What is the function of the left and right ventricle?

a.Left: Pumps deoxygenated blood to the lungs Right: Pumps oxygenated blood around the body

b.Left: Pumps oxygenated blood around the body Right: Pumps deoxygenated blood to the lungs

c.Left: Pumps oxygenated blood to the lungs

Right: Pumps deoxygenated blood around the body

d.Left: Pumps oxygenated blood to the lungs Right: Pumps oxygenated blood around the body

4.The factor which most increases the risk of coronary heart disease is:

a.family history

b.lack of exercise

c.obesity

d.smoking

5.What is the carcinogenic content of a cigarette?

a.Nicotine

b.Tar

c.The type of tobacco

d.The wrapping

6.Angina is a pain associated with the heart which is felt only across the chest. This statement is:

a.true

b.untrue

7.List the symptoms of carbon monoxide poisoning:

a.ruddy complexion, headache, stomach cramps, nausea, lethargy

b.difficulty in breathing, ruddy complexion, headache, stomach cramps, nausea, lethargy

c.ruddy complexion, headache, nausea, giddiness, stomach cramps

d.ruddy complexion, headache, tightness across the forehead, impaired judgement

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			Questions		2
	8.	Why is it essential to ensure that the combustion heaters are serviceable?
		a.	To prevent carbon dioxide poisoning and possible fire	2
		b.	To prevent carbon dioxide poisoning, possible fire or explosion
		c.	To prevent carbon monoxide poisoning		Questions
		d.	To prevent carbon dioxide poisoning and possible fire
	9.	The effects of smoking, particularly in relation to aviation are:
		a.	an early onset of hypoxia due to an apparent increase in altitude and a
			degradation of night vision
		b.	an early onset of hypoxia due to an apparent increase in altitude
		c.	an early onset of hypoxia due to an apparent increase in altitude up to a
			maximum of 40 000 ft
		d.	an early onset of hypoxia due to an apparent increase in altitude with a
			resulting risk of anaemia
	10.	Will smokers experience hypoxia at a lower or higher cabin altitude than non-
		smokers?
		a.	At a higher cabin altitude
		b.	At a lower cabin altitude
		c.	Both will experience hypoxia at approximately the same cabin altitude
		d.	Smoking, although harmful in other ways, lessens the effects of hypoxia
	11.	A pilot must wait at least 24 hours before flying after donating blood.
		a.	True
		b.	False
	12.	Where does the exchange of oxygen and carbon dioxide + water vapour take
		place:
		a.	the arteries
		b.	the veins
		c.	the capillaries
		d.	the pulmonary veins and arteries
	13.	The normal range of blood pressure is:
		a.	systolic 120 mm Hg and diastolic 80 mm Hg
		b.	systolic 80 mm Hg and diastolic 120 mm Hg
		c.	systolic 120 mm Hg and diastolic 120 mm Hg
		d.	systolic 80 mm Hg and diastolic 80 mm Hg
	14.	Pressoreceptors affect the:
		a.	ECG readings
		b.	tightening and relaxation of the blood vessels only
		c.	EEG readings
		d.	tightening and relaxation of the blood vessels and the pulse rate

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		2		Questions
				15.	Hypotension is:
	2				a.	high blood pressure
					b.	high pulse rate
	Questions				c.	low blood pressure
					d.	low pulse rate
				16.	Haemoglobin has a preference to carbon monoxide over oxygen by a factor of:
					a.	100 – 120
					b.	210 - 250
					c.	200
					d.	10 - 20
				17.	Treatment of carbon monoxide poisoning should include:
					a.	immediate descent to MSA
					b.	turn up cabin heat
					c.	keep the patient’s body temperature as low as possible
					d.	stop all smoking
				18.	Low blood pressure can lead to:
					a.	low body temperature
					b.	reduced tolerance to g-forces
					c.	infarct
					d.	angina
				19.	Cardiac output (the quantity of blood pumped by the heart per unit time), is the
					product of:
					a.	stroke volume and the heart rate (pulse rate)
					b.	stroke volume and viscosity of the blood
					c.	pulse rate and strength of the ventricle muscle
					d.	pulse rate only
				20.	Internal Respiration is:
					a.	the brain’s control of the pulse rate
					b.	the exchange of oxygen with carbon dioxide and water in the cells
					c.	sighing
					d.	the retention of breath

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Questions 2

Questions 2

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