Physiology Flashcards
- What’s the average volume, tidal volume, residual volume and vital capacity of the lungs ?
IMCA TEST
Average total volume: 6 litres
Tidal volume: 0,5 litres
Vital capacity: 4,5 - 5 litres Inspire 21% O2 expire 16/17% O2
Residual volume: 1,5 litres Inspire 0,03% Co2 expire 4/5%Co2
- Which of the following do not affect the on set of hypothermia?
a) normal air breathing
b) activity
c) body build
d) drugs
a) normal air breathing
- A hypothermic diver is rescue conscious with a slow heart rate, would you give him?
a) a brandy
b) cardiac massage
c) a warm drink
d) a warm bath
d) a warm bath
- A hyperthermia occurs when the bodies core temperature reaches approximately?
a) 41c
b) 39c
c) 37c
d) 35c
b) 39c
- Carbon dioxide poisoning is called?
a) hypocapnia
b) hyperoxia
c) hypoxia
d) hypercapnia
d) hypercapnia
- Haemoglobin prefers carbon monoxide to oxygen by about?
a) 100 times
b) 200 times
c) 460 times
d) 1000 times
b) 200 times
- Toxic levels of carbon monoxide is commonly a by-product of?
a) respiration
b) blood contamination
c) engine exhausts
d) shallow breathing
c) engine exhausts
- A common sign of CO poisoning is?
a) rapid breathing
b) sweating
c) visual disturbance
d) cherry red lips
d) cherry red lips
- CO2 poisoning does not give the following symptom?
a) rapid pulse
b) mild euphoria
c) headache
d) increased respiration
b) mild euphoria
- When breathing air, nitrogen narcosis starts about?
a) 20 msw
b) 30 msw
c) 40 msw
d) 50 msw
b) 30 msw
- Normal CO2 levels in DDCs should be kept below?
a) 0.05 bar
b) 5 SEP
c) 50 mb
d) 0.005 ba
d) 0.005ba
Co2 levels in the bell and chambers should be kept between 5-10 mbar
- The maximum allowable ppm co2 read inside a chamber at 40 msw is?
a) 5000 ppm
b) 500 ppm
c) 1000 ppm
d) 800 ppm
c) 1000 ppm
5000/5 = 1000ppm
- Neurological DCI involving the lower limbs is usually associated with gas bubbles in which area of the spinal cord?
a) sacral area
b) cervical area
c) thoracic area
d) lumbar area
d) lumbar area
- After a pneumothorax injury, a diver may not return to diving before?
a) not less than 28 days after full recovery
b) 3 months after full recovery
c) 1 week after treatment
d) 24h after treatment
b) 3 months after full recovery
Return to diving only after review by a diving medicine specialist.
- Where in the body is the sternum?
a) arm
b) spine
c) chest
d) head
c) chest
- Which of these gases diffuses fastest in our body tissues?
a) oxygen
b) nitrogen
c) carbon dioxide
d) helium
d) helium
- Which of the tissue will absorb more gas in a given time?
a) brain
b) bone
c) skin
d) stomach
a) brain
- Which normally has a greater bloody supply?
a) brain
b) bone
c) skin
d) stomach
a) brain
- Which is a symptom of static limb pain?
a) dizziness
b) localised pain
c) weakness
d) deafness
b) localised pain
- A diver shows symptoms of acute progressive limb pain DCI on his last water stop. What action should you take?
a) recompress him to first stop depth
b) double stop time
c) add stop to bottom time
d) surface diver and give him a therapeutic treatment
d) surface diver and give him a therapeutic treatment
- Which is a symptom of pain only bend?
a) dizziness
b) localised pain
c) weakness
d) deafness
b) localised pain
- A pain in the centre of the chest could suggest?
a) acute static limb bend
b) nitrogen narcosis
c) pneumomediastinum
d) barodontalgia
c) pneumomediastinum
- High frequency hearing loss following a non stop dive would suggest?
a) burst eardrum
b) oval window rupture
c) round window rupture
d) blocked Eustachian tube
c) round window rupture
- In a DCI, air or gas embolism is most likely to cause a blockage of?
a) venous circulation
b) arterial circulation
c) lymphatic circulation
d) femoral vein
b) arterial circulation
- The immediate action for a pneumothorax presenting under pressure is?
a) stop deco
b) sat deco
c) raise PO2 and slow deco
d) give pure O2 and hold for 30 min
a) stop deco immediately
- The IMCA initial treatment for air embolism is?
a) 18 msw on O2
b) 18 msw on air
c) 165 fsw on air
d) 165 fsw on O2
a) 18 msw on O2
- A diver complains of a sharp, sudden ear pain followed by a vertigo whilst working between 0-12 msw. The ear pain disappears after few minutes. What would you suspect?
a) Pyo infection
b) facial squeeze
c) ear drum rupture
d) serious deco illness
c) ear drum rupture
- Hypoxia occurs when ppo2 drops bellow?
a) 100mb
b) 160mb
c) 200mb
d) 400mb
b) 160mb
- Which is the first dependable sign usually seen underwater for acute CNS oxygen toxicity ?
a) convulsion
b) short of breath
c) vertigo
d) nausea
a) convulsion
- Which of the following would increase the risk of O2 poisoning ?
a) rest
b) exercise
c) hypocapnia
d) fluids intake
b) exercise
- Chronic ( pulmonary ) oxygen toxicity caused by exposures to oxygen of?
a) below 600mb
b) over 4ba
c) over 600mb
d) over 14ba
c) over 600mb
- A common sign of pulmonary oxygen toxicity is?
a) dilated pupils
b) vertigo
c) tinnitus
d) dry chest cough
d) dry chest cough
- During the oxygen breathing, the pulse rate?
a) rises
b) falls
c) remains the same
d) varies with po2 being breathed.
b) falls
- The body normal core temperature is?
a) 35°c
b) 37°c
c) 39°c
d) 37°c
b) 37°c
- Which is the most frequent first sign of acute oxygen toxicity in the DDC?
a) lightheadness
b) sweating
c) convulsion
d) hallucinations
c) convulsion
- Which of the following is not found in hypothermia cases?
a) amnesia
b) heartbeat changes
c) increased pulse
d) lack of co-ordination
c) increased pulse
- What’s the main cause of decompression illness?
Inadequate or too fast decompression.
Any omitted decompression should be treated on therapeutic table.
The time for complete nitrogen desaturation is 12h.
- How many times fatty tissue absorb nitrogen than lean tissue?
5 more times soluble.
- Serious DCIs like spinal (most common), cerebral, vestibular tend to occur…..
Usually occurs within 10min after surfacing or completion of decompression. (could be longer)
- What’s the signs and symptoms of skin, joint DCI?
Itching may be felt over the affected area and rash may appear
Pain in joint at site of DCI
- What’s the symptoms of spinal DCI?
- girdle pain particularly in lumbar area
- numbness or tingling
- weakness or paralysis
- loss of bladder and bowel control
Generally symptoms occur on both sides of the body below the point of the bubble formation - pain in mid thigh may indicate spinal DCI
- What’s the symptoms of cerebral DCI?
- headache and dizziness
- visual disturbance
- hearing difficulties
- confusion, hallucinations
- personality changes
- loss of co-ordination
- paralysis down one side of the body
- collapse
- What’s the signs and symptoms of vestibular DCI?
- vertigo
- nausea
- hearing difficulties
- nystagmus
- tinnitus
- Important points to know about DCI and AGE….
- Serious DCI and AGE show very similar CNS symptoms, AGE symptoms usually present themselves on or soon after surfacing whereas DCI symptoms develop up to 12h after the dive.
- Pain only symptoms can mask serious symptoms, if in doubt treat for the worse case
- All DCI should be reported to the OIM or barge master/captain.
- Pain only DCI may be fit to dive again after 7 days
- Serious DCI company medical officer must examine the diver before returning to diving.
- What’s the signs and symptoms of hypothermia? How you would treat it?
On set of hypothermia is when body temperature drops to 35°C or below. Symptoms: - speech impairment - fixed ideas - sluggish reactions - confusion - amnesia
Treatment: immerse trunk in bath of elbow hot water ( arms and legs out to avoid latent core drop) or if no water available use space blanket.
WATCH FOR CARDIAC ARREST!
- What’s the signs and symptoms of hyperthermia? Dictate some of the causes?
On set of hyperthermia occurs when the body temperature raises to 39°C.
Symptoms:
- pulse rapid and feeble
- initial deep respiration becoming very shallow and rapid
Causes:
- too rapid compression
- too high humidity
- excess of fat
- hyperthermia can occur in water temperature above 36°C when at rest, or over 30°C when working
- hot water suit heating to high
- How would you treat Hyperthermia?
Treatment in chamber: - reduction of body temperature - increase of fluid intake - stop compression and flush - remove excess clothing - sponge back of neck with tepid water On surface - remove from source - copious fluid intake
- What’s a barotrauma. State types of non-serious and serious barotrauma?
Barotrauma is a pressure injury
Non serious types:
- Nips (skin) cause by suits
- Ears (most common)
- Sinus
- dental (barodontalgia)
- middle ear squeeze cause by blocked Eustachian tube
- rupture eardrum: upsets balance/vertigo/nausea
Affects hearing
Risk of infection
Serious: bloodshot eyes, bruised and puffy cheeks - facial squeeze
Symptoms: chest pain, bleeding lungs, difficulty in breathing
Treatment: treat for shock; give pure O2, medical aid
- State types of pulmonary barotrauma?
- arterial gas embolism
- subcutaneous emphysema
- mediastinal emphysema
- pneumothorax
- Explain signs and symptoms of arterial gas embolism ( AGE)?
Symptoms: similar to CNS, DCI, normally occurs immediately on surfacing or 5 min
Treatment: transport to chamber and recompress immediately to 18 msw on oxygen
- Explain signs and symptoms of subcutaneous emphysema?
Gas trapped under the skin usually around the neck and shoulder area
Symptoms:
- puffiness around neck,
- brassy monotone voice,
- Crepitus
- Explain signs and symptoms of mediastinal emphysema?
Gas trapped in the space between the lungs and around heart (also called Pneumomediatinum)
Symptoms:
- difficulty in breathing,
- pain behind the sternum
Treatment:
Stop deco and give pure or enriched O2 on bibs, if on surface give O2 mix and seek medical aid.
DO NOT RECOMPRESS UNLESS LIFE THREATENING!!
- Explain signs and symptoms of pneumothorax?
Gas trapped between lungs and pleura.
Symptoms:
- chest pain gets worse on ascent,
- restricted chest movement,
- difficulty breathing, “tracheal shift”
Treatment: stop deco and give raised O2 on bibs. If on surface give O2 and seek medical aid.
DO NOT RECOMPRESS UNLESS LIFE THREATENING !!
- Explains the difference between CNS acute (rapid) and pulmonary chronic (slow) hyperoxia.
Acute: cause by breathing O2 above 1.6bar in water or above 2.8 bar in DDC.
Chronic: cause by breathing O2 for long periods with PPO2 above 0.6bar (600mb)
- What’s signs and symptoms of acute hyperoxia and would you treat it?
Symptoms: V - vision ( tunnel vision) E - ears ( ringing/tinnitus) N - nausea T - twitching I - irritability D - dizziness C - convulsions: would be a first visual sign
Treatment:
- remove from cause
- stop deco
- check for injury
- protect airway
- What’s signs and symptoms of chronic hyperoxia.
Symptoms:
- dry irritated throat
- tight feeling in the chest
- dry cough, painful, non-productive
- painful fingertips
- shortness of breath
Treatment:
- Remove from cause
- observe patient
- check for neurological symptoms
- What’s hypoxia and what’s the cause of it?
Hypoxia is the lowering of oxygen level in the body.
Cause: when breathing O2 less than 0.16bar (160mb) or 16 SEP (16% on surface)
- What’s are Symptoms of hypoxia?
- cyanosis (blue fingers and earlobes)
- breathing
- increasing heart rate
- poor co-ordination
PS: most of symptoms pass unnoticed leading straight to collapse.
- What’s Anoxia?
Is Complete lack of oxygen.
An: no
Oxia: oxygen
- What’s Hypercapnia and what’s the cause of it?
Hypercapnia is the CO2 poisoning, usually caused by inadequate ventilation of mask, overexertion or soda lime not changed regularly.
On set : 20.000ppm = 2 SEP = 0.02ba = 20mb
Unconscious: 150.000ppm = 15 SEP = 0.15ba = 150mb
- What’s the symptoms and treatment for hypercapnia?
Symptoms: - increase of respiration and pulse rate - headache - sweating - dizziness - nausea - anxiety - unconsciousness Treatment: Stop working and flush through helmet.
- What’s the cause and what you need to know about carbon monoxide (CO) poisoning?
CO poisoning is cause by breathing impure air from engines exhaust. Example from a badly sited compressor intake or from breakdown in a overheating compressor)
- BS EN 12021: CO should not exceed 5ppm in air from a compressor or 0.02mb in DDC.
- CO has affinity to haemoglobin 200 times greater then 02.
- What are the symptoms of carbon monoxide poisoning and how would you treat it?
Symptoms:
- cherry red lips
- breathless on exertion
- lassitude
- dizziness
- tinnitus
- confusion
- loss of consciousness
Treatment:
- Change gas supply
- jump standby to assist divers ascent
- recompression, administrator pure O2 by bibs
- What’s nitrogen narcosis? What’s the cause and symptoms of it.
Nitrogen becomes narcotic beyond 30msw or PPN2 of 3.16 bar absolute.
Cause is the increased of partial pressure of the nitrogen.
Symptoms:
- euphoria
- drunkness
- inability to concentrate
- dizziness
- unconsciousness
Treatment: decrease depth and change breathing mix.
- What the DMAC07 recommendations for flying after diving?
- NO STOP DIVES: 2h @ 2000ft or 8h or 24h for all other intercontinental flights
- STOP DIVES: 12h @ 2000ft or 24h for all other intercontinental flights
- THERAPEUTIC TREATMENT: 24h @ 2000ft or 72h for all other intercontinental flights, when immediate and complete resolution of treatment on first recompression.
- any residual symptoms or lack of immediate response, contact diving medical specialist - no flying
- What’s the most common recurring problem from a burst eardrum?
Infection
- Complete desaturation of nitrogen from the body is usually:
a 4 hours
b 12 hours
c 24 hours
d 72 hours.
B
- During a surface decompression it is reported that the diver’s eyes are flicking uncontrollably from side to side. He also feels unwell. He is likely to be suffering from:
a Decompression sickness
b Carbon monoxide poisoning
c Oxygen poisoning
d Carbon dioxide poisoning.
a
After surfacing a diver complains of feeling weak and fatigued. He may be suffering from:
a Overwork
b Type II decompression sickness
c CO2 poisoning
d O2 poisoning.
b
On completion of an air dive, the diver complains of visual disturbances and pain in his stomach. Which course of action would be considered most appropriate:
a Observe for further developments
b Send diver to medic
c Contact Company Doctor for advice
d Pressurise diver in a DDC and treat for decompression sickness.
d
How does nitrogen solubility in fatty tissue compare to its solubility in lean tissue?
a More soluble
b No difference
c Less soluble
d Insoluble
a
Several hours after an air dive, a diver complains of tunnel vision and pain in his hips. These are symptoms of:
a Oxygen Toxicity
b Type I decompression sickness
c Acute bone necrosis
d Type II decompression sickness.
d
After completing an uneventful Air dive to 100 fsw, the diver complains of feeling unwell, dizzy, pain in his head and elbows and of visual disturbances. What immediate action must be taken:
a Observe for a while to see if symptoms worsen
b Recompress to 60 fsw and administer O2
c Seek medical advice
d Recompress to 165 fsw and administer O2.
b
Barotrauma is:
a Emphysema
b Decompression sickness
c Pressure related injury
d Pneumothorax.
c
Middle ear barotrauma is caused by:
a Blockage in the eustachian tube or outer ear
b Blockage between the eustachian tube and the cochlea
c Blockage between the eustachian tube and the trachea
d Blockage between the outer ear and pinna.
a
Pneumothorax is caused by:
a Air escaping from the lungs into the surrounding tissue
b Escape of air from lungs into the bloodstream
c Air escaping through the lung surface and collecting in the pleural cavity.
d b and c.
c
Immediately following a dive, a diver complains of loss of power and sensation down one side, severe headache and he seems drowsy. Is he suffering from:
a Type II Decompression sickness
b CO2 poisoning
c Arterial gas embolism
d Head injury.
c
Following an uneventful dive, a diver complains of a pain in his chest and difficulty in breathing. On examination, you notice lack of movement on the right side of his chest and the trachea is displaced. What would you suspect?
a Subcutaneous emphysema
b Mediastinal emphysema
c Pneumothorax
d Arterial gas embolism.
c
Anoxia is:
a High O2
b Low O2
c Complete lack of O2
d Normal level of O2.
c
Hypoxia is:
a No O2
b Low O2
c High O2
d Normal level O2.
b
Hyperoxia is:
a Normal level O2
b Too High O2
c Too Low O2
d Complete lack of O2.
b
If gas ruptures from the lung tissue and is trapped between the heart and lungs, it is known as:
a Pneumothorax
b Mediastinal emphysema
c Subcutaneous emphysema
d Gas embolism.
b
Gas in the pleural cavity is:
a Surgical emphysema
b Pneumothorax
c Gas embolism
d Barotrauma.
b
The diver leaves the bottom and arrives on surface unconscious. What immediate actions would you take?
a Recompress to 165 fsw (50 metres)
b Recompress to 165 fsw (50 metres) and resuscitate and give O2
c Recompress to 60 fsw (18 metres) and resuscitate and give O2
d Recompress to 60 fsw (18 metres).
c
A blocked eustachian tube will cause:
a Emphysema
b Decompression sickness
c Aural barotrauma
d Toothache.
c
A diver blows to the surface, where he complains of difficulty in breathing, chest pain and visual disturbance. Which of the following is he likely to be suffering from:
a Type I Decompression sickness
b Type II Decompression sickness
c Pneumothorax
d Arterial gas embolism.
What immediate actions would you take?
a Seek medical advice
b Return him to water and complete the omitted stops
c Recompress DDC on a treatment table
d Recompress in DDC and complete the omitted stops.
D
C
Of the following durations and partial pressures, which is more likely to cause CNS O2 toxicity:
a 8 hours 0.8 ATA
b 12 hours 2.5 ATA
c 24 hours .45 ATA
d 120 minutes 1.1 ATA
b
Pulmonary O2 toxicity may occur when the PPO2 exceeds:
a 0.4 ATA
b 0.45 ATA
c 0.6 ATA
d 1.6 ATA
c
How much O2 will a diver consume at 70 msw at rest:
a 2.0 - 4.0 L/min
b 0.25 - 0.5 L/min
c 1.5 - 2.0 L/min
d 35 - 40 L/min
b
A diver complains of a sore throat, pain behind the breastbone (substernal) and a dry cough. These are signs of:
a CO poisoning
b CO2 poisoning
c CNS O2 poisoning
d Pulmonary O2 poisoning.
d
The ratio between the amount of O2 consumed and CO2 produced is almost:
a 1 : 1
b 1 : 2
c 2 : 1
d 3 : 1
a
Hypercapnia is:
a High O2
b Excess carbon dioxide
c Excess carbon monoxide
d Shortness of breath.
b
During a dive, the diver complains of sweating, nausea, headache and is breathing rapidly. He is suffering from:
a Nitrogen narcosis
b CO poisoning
c CO2 poisoning
d Pulmonary O2 toxicity.
c
Carbon monoxide has an affinity for haemoglobin:
a Equal to oxygen
b Less than oxygen
c 100 times greater than O2
d 200 times greater than O2
d
An excessive dead space in a diver’s breathing equipment can lead to:
a Increased carbon dioxide levels in body
b Increased oxygen
c Decrease in the carbon dioxide level
d Decrease in oxygen.
a
Nitrogen narcosis usually occurs at a Seawater pressure of:
a Above 1.6 bar A
b Above 4 bar A
c Above 5 bar A
d Above 6 bar A.
b
Which of the following constitutes an unacceptable rise in body temperature:
a Body core temperature rises above 37ºC
b Body core temperature rises above 39ºC
c Body core temperature falls below 37ºC
d Body core temperature falls below 35ºC.
b
Hypothermia occurs when:
a Body core temperature rises above 37ºC
b Body core temperature falls below 35ºC
c Body core temperature falls below 37ºC
d Body core temperature fluctuates between 37ºC and 35ºC.
b
What action would you take with a diver suffering from nitrogen narcosis?
a Rest and flush helmet
b Increase his depth
c Flush helmet with oxygen
d Reduce his depth
d
Which of the following is the ideal method of treatment for hypothermia in a severe case:
a Cover with a blanket and place in front of a heater
b Rewarm gradually by immersion of the trunk in a warm bath
c Encourage exercise
d Rewarming and hot drinks.
b
Body tissues receive oxygen from:
a. Heart
b. Veins
c. Arteries
d. Capillaries
d
Which chemical substance in the blood is the main oxygen carrier?
a. Red blood cells
b. Plasma
c. Haemoglobin
d. Serum
c
An increase in the respiratory rate of a diver while working may be due to:
a. An increase in carbon monoxide in his blood
b. An increase in carbon dioxide in his blood
c. Decrease of CO
d. Decrease of CO2
b
Oxygen is used in decompression to:
a. Prevent formation of bubbles
b. Improve the elimination of inert gas
c. Prevent arterial gas embolism
d. Slow down the elimination of inert gas
b
The vital capacity of your lungs is:
a. The maximum volume of air which can be expired after maximal inhalation.
b. The volume of air in the lungs at rest
c. The greatest volume of air your lungs can hold
d. The volume of air remaining in your lungs following a normal breath
a
Which of the following is the maximum depth you would administer pure oxygen in a therapeutic treatment?
a. 10 msw
b. 18 msw
c. 25 msw
d. 50 msw
b
A diver suffering from an arterial gas embolism is recompressed in order to:
a. Help improve the circulation to the brain
b. Reduce the size of the bubble causing the embolism
c. Reduce the circulation therefore reduce the swelling within the brain
d. Increase the blood flow thereby allowing the bubble to be dislodged
b
A diver complains of hearing difficulties, tunnel vision, dizziness and twitching of his facial muscles while on BIBS. What is he likely to be suffering from?
a. Chronic O2 poisoning
b. Acute O2 poisoning
c. Type 2 DCS
d. Hypoxia
b
Which of the following is the recommended levels of PPO2 for saturation storage?
a. 0.21 - 0.35
b. 0.35 - 0.45
c. 0.45 - 0.5
d. 0.5 - 0.6
b
During decompression a diver complains of chest pain and difficulty in breathing. You halt the decompression and the symptoms stabilise. You recompress him and he gets relief, if the symptoms recur on recommencing decompression what would you suspect he is suffering from?
a. Type 1 DCS
b. Acute O2 toxicity
c. Pneumothorax
d. Emphysema
c
Which of the following is most likely to cause vestibular DCS?
a. Nitrox saturation
b. Change of atmosphere from mixed gas to air
c. Change of atmosphere from air to mixed gas
d. Excessive hard work
b
Which of the following is the ideal method of treatment for hypothermia in a severe case?
a. Cover with a blanket and place in front of a heater
b. Rewarm gradually by immersion of the trunk in a warm bath
c. Encourage exercise
d. Rewarming and hot drinks
b
Hypoxia will occur if a diver breathes gas with a ppO2 less than:
a. 1.6 Bar
b. 0.5 Bar
c. 0.35 Bar
d. 0.16 Bar
d
Hypercapnia is:
a. High O2
b. Excess carbon dioxide
c. Excess carbon monoxide
d. Shortness of breath
b
Which law explains the mechanism of injury in cases of barotrauma?
a. Boyles law
b. Charles Law
a
Which laws explain the mechanism of injury in cases of decompression sickness and gas toxicities?
a. Boyle and Charle’s Law
b. Dalton and Henry’s Laws
b
