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Independents' Day

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Diving medicine

Use our quick quiz to check your clinical knowledge

1 - The following conditions are a bar to diving

A Epilepsy

B Insulin-dependent diabetes

C Pregnancy

D Asthma

A True ­ all seizure disorders are an absolute disqualification.

B True ­ disqualification advised from diving as hypoglycaemic episodes are unpredictable. Divers can have a BSAC medical assessment which may permit some IDDM patients to dive.

C False ­ not recommended but little evidence available.

D False ­ but this is a tricky one. There is such variation in the spectrum of this condition. Generally, asthmatics requiring medication are advised not to dive. Even very mild asthmatics on no treatment should be very cautious.

2 - Flying after diving

A There are no restrictions

B Flying is allowed on a pressurised aircraft immediately after diving

C Time to fly should be calculated from dive tables

D Diving at altitude requires special dive tables

A False ­ patients must not fly after diving for a required period of time calculated from dive tables, depending on the depth and time of their dive.

B False ­ pressurised aircraft are not fully pressurised and passengers will have some desaturation in flight. Injured divers who need to be flown to a hospital must be flown at less than 1,000 metres altitude.

C True ­ dive tables are mathematical tables used by divers to calculate safe diving time and depth limits.

D True ­ for example diving in a mountain lake.

3 - Pneumothorax

A Can be a direct result of uncontrolled ascent

B Is unlikely in the last 10 metres of ascent

C Should be treated by taking the diver down in the water to a depth of 10 metres

D Pneumothorax, if spontaneous, is a bar to diving

A True ­ breath holding can literally burst the lung as gas expands on ascent.

B False ­ in fact, it is most likely to occur during this part of the dive as this is when the greatest pressure changes happen.

C False ­ standard medial treatment of pneumothorax is required.

D True ­ history of a spontaneous pneumothorax is an absolute contraindication to diving due to high recurrence rates and also the risk of pneumothorax while diving.

4 - Decompression illness

A Is also known as the 'bends'

B Is caused by the presence of gas bubbles in the body's tissues

C Can present with joint pains

D Should be treated conservatively

A True.

B True ­ if a diver ascends without required decompression stops to allow excess nitrogen to be 'blown off', bubbles will form in the body tissues producing a wide spectrum of symptoms known as decompression illness (DCI).

C True ­ the commonest presentation of DCI is pain (40 per cent) followed by numbness, headache, fatigue and collapse.

D False ­ absolutely not. See question five.

5 - Treatment of decompression illness involves

A Recompression in a chamber

B 100 per cent oxygen

C IV fluid administration

D Sending the diver back underwater

A True ­ this is the most effective way of reducing in size or removing the offending bubbles from the patients' body tissues.

B True ­ patients with DCI will have impaired gas exchange. Oxygen can decrease damage to ischaemic tissues.

C True ­ divers are often dehydrated and this improves outcome.

D False ­ this would in fact treat the DCI quite well but if the patient lost consciousness or had other complications this situation would be incredibly dangerous.

6 - A diver is found unconscious on a beach ­ the following conditions are possible causes:

A Hypothermia

B Pneumothorax

C Envenomation

D Decompression illness

A True.

B True.

C True.

D True ­ all of these are possible.

7 - Marine envenomation can be extremely painful and sometimes lethal ­ the following are considered useful treatments:

A Dousing jellyfish stings with vinegar

B Administration of antivenom

C Immersion of affected area in hot water

D Narcotics and ITU admission

A True ­ this can deactivate remaining nematocysts and give some pain relief.

B True ­ antivenom exists for box jellyfish, sea snakes and stonefish.

C True ­ heat can deactivate some fish venoms.

D True ­ the doses of narcotics required are usually very high and require life-support.

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