Seafarer’s Health : Risk Factors Operational factors which can degrade crew performance Temperature Ships in Service Training Material A-M CHAUVEL

Seafarer’s Health : Risk Factors

Operational factors which can degrade crew performance

Temperature

Ships in Service Training Material A-M CHAUVEL

Heat : Hyperthermia

Temperature effects on Humans

Cold : Hypothermia

Humidity



Cold : Hypothermia

Humidity


"Hypo" means under. "Therm" is a unit of heat.The normal core temperature for you body is

37.5 degrees C or 99.5 degrees F .

"Core temperature" means the temperature of internal body organs, particularly the heart,

brain, lungs, kidneys, stomach, and intestines.

An abnormally low core temperature is the condition of hypothermia.

In this condition normal muscular and mental abilities are impaired.

If this condition continues to deteriorateit will lead to death.

What is Hypothermia


- 1. Sudden exposure to cold water or

- 2. Prolonged exposure to the cold conditions of temperature, water, and wind or

- 3. A very slow and prolonged period of cold conditions and prolonged fatigue, exhaustion, and lack of food.

When heat loss exceeds heat production and heat retention

hypothermia is the result.

What causes Hypothermia


0

5

10

15

20

25

30

35

Minutes

Cold shock

Swim failure

Immersion Hypothermia

Post-Immersion Collapse

Immersion in Cold Water


Water temperature

Fahrenheit ( °F )

Water temperatureCelsius ( °C )

Exhaustionor

Unconsciousness

Expected timeof survival

( in minutes )

32°5 0°C Under 15 min. Under 15 - 45 min.

32°5 - 40°F 4.4°C 15 - 30 min. 30 - 90 min.

40° - 50°F 10°C 30 - 60 min. 1 - 3 hours.

50° - 60°F 16°C 1 - 2 hours. 1 - 6 hours.

60° - 70°F 21°C 2 - 7 hours. 2 - 40 hours.

70° - 80°F 27°C 3 - 12 hours. 3 - Indefinitely

Over 80°F > 27°C Indefinitely

Immersion in Cold Water


- Normal oral temperature

- Metabolic rate increased

- Maximum shivering seen / impaired judgment

- Severe clouding of consciousness

- Most shivering ceases and pupils dilate

- Blood pressure may no longer be obtainable

- Severe slowing of pulse / respiration

Increased muscle rigidity

Loss of consciousness

Ventricular fibrillation

- Loss of deep tendon. skin and capillary reflexes

Patients appear clinically dead

Complete cardiac standstill

Effect of Cold on Body

Temperature( °C )

37

36

35

33

32

31

28-30

27


Body Signs/Symptoms Temperature (Rectal )

37.5°C Normal

36.0°C - Feel cold

33.0°C Muscle stiffness

Body core temperature below 35.0°C = Hypothermia = Hospital

34.0°C - Clumsy Irrational Confused may appear drunk

35.0°C - Shivering

30.0°C - Semi-conscious No response to painful stimulus

29.0°C - Slow pulse and breathing

Below 28.0°C, No vital signs, Cold, Do not give up treatment

31.0°C - Semi-conscious

28.0°C - Cardiac arrest No obvious pulse or breathing Pupils dilated

32.0°C Shivering stops, Collapse, transfer to hospital, Urgent

Seek dry shelter, replace clothing with dry including shocks, gloves, hat, cover neck, insulate whole body including head from cold. Exercise but avoid sweating. External warmth (bath, fire) ONLY if Core Temperature above 35°C. Warm sweet drink and food (High calories).

No exercise, handle gently, rest. No external warmth (except to chest, trunk). Warm sweet drinks and calories. Internal warming via warm moist air (external air, steam) or warm moist oxygen (40-42°C at mask).

Nothing by mouth. Check airway remains open. May tolerate plastic airway, put in recovery position, check airway, turn every 2 hours to protect skin, monitor pulse and breathing.Slow mouth-to-mouth breathing at victim’s own rate (may be very slow). Check airway, CPR, with mouth-to-mouth breathing. Aim for normal CPR rates of 12-15 breaths/min. and 80-100 compressions/min., but slower rates of 6-12 breaths/min. and 40-60 compressions may be adequate. Continue for as long as you can.

Hypothermia Warning Signs


Hypothermia : Prevention

- First Line of Defense : Avoid exposure, stay dry, be aware of the wind, understand and don’t underestimate the cold.

- Second Line of Defense : Terminate exposure get out of the wind and the rain, and go inside.

- Third Line of Defense : Watch yourself and others for the symptoms.

- Fourth Line of Defense : Treatment


The basic principle of rewarming a hypothermiavictim is to : - conserve the heat they have (heat retention) - and warm the victim (heat production), getting them back to normal.

In general

1- Get the victim dry and out of the wind.2- Gently remove all wet clothes (get dry).3- Insulate the body, including head and neck (heat retention).4- Apply mild heat to body core and rewarm gradually (heat production).5- Handle gently.

Treatment of Hypothermia


http://tjsamson.client.web-health.com/web-health/topics/GeneralHealth/generalhealthsub/generalhealth/common_symptoms/headaches.html

Heat : Hyperthermia


Humidity


What is Heat Illness and Hyperthermia

Heat illness can range from mild heat exhaustion

to the most severe form,heat stroke.

Heat stroke is a dysfunction of

the central nervous system that makes the body stop sweating

and organs stop working.


Hyperthermia can be defined as a rectal temperature

greater than 98.6° F (37.0° C).

Determination of anexternal source of heat gain versus an actual febrile state

can be made by observing a higher rectal temperature versus a distal temperature

of the foot.

What is Heat Illness and Hyperthermia


Unless prompt treatment is received, they suffer the serious or even fatal consequences of heat stroke.

Usually it is the cumulative effect of heat for days on, without the relief effect of cool nights, resulting in heat exhaustion, which may lead to death.

Effects of Hyperthermia on body


Every year thousand of people die from heat related causes

At most risk level are : Young children and elderly, people with weight, chronic ailments or other health problems, and those on

medications or with alcohol or drug dependency.

Studies had shown strong associations betweenthermal comfort and worker output ( productivity ).The body has certain evolutionary tolerances but

the limits are to some extent already set.

The formula that describes thermal comfort is :

Hb = M x R x C - E

where Hb = body heat storage load, M = metabolic heat gain

R = radiant or infrared heat load C = convection heat load E = evaporative heat loss.

Heat illness : Temperature


High Temperature + High Humidity + Physical Work = Heat Illness

TemperatureIn Celsius

Relative Humidity

29.4

26.7

37.8

35.0

32.2

40 %

30 %

70 %

60 %

50 % Caution

Less hazardous

Danger

Heat illness : Temperature & Humidity


Research concluded there is a range of combined temperatures and humidities

that provides comfort to most people.

Human Comfort : Temperature & HumidityIn

do

or

Air

Tem

per

atu

re (

°F)

Relative Humidity (%)


There is no one temperature and humidity condition at which everyone is comfortable.

The shaded area represent the "Comfort Zone.”


Water loss

Decreased bloodvolume

Heat gain

Increased bodytemperature

Decreasedblood flow

Hyperventilation

TinglingNumbness

CrampsFainting

Strain oncirculatory

system

Less blood flow to skinLess sweating

Organ damageBrain, Lungs,Kidneys, Liver

Damage to centralnervous system

Cessation of sweatingVasoconstriction

Shivering

Hyperthermia Process

Age -

Chronic medical -Conditions

Deprivation -

Fever -

History of -heat stroke

- Illness

- Medications

- Obesity

- Physical fitness

- Sleep

Hyperthermia : Risk is increased by

Leadership

Alcohol -

- Missed Meals

- Morale

Hygiene -

Caffeine -

Dehydration -

- Sunburn

- Stupidity

- Smoking

- Skin Disease



- Tachypnea - Apnea - Tachycardia - Hypotension - Flushing - Warm extremities - Irritability - Diaphoresis - Poor feeding - Lethargy - Hypotonia - Extended posture - Weak or absent cry - Skin temperature greater than core temperature

Hyperthermia : Signs and Symptoms

The signs and symptoms of hyperthermia secondary to overheating include :

Hyperthermia Treatment

Anyone who experiences headache, nauseaand fatigue after exposure to heat may have some degree of heat-related illness.

For a victim of heat exhaustion :

- Move the person out of the sun and into a cool place ( preferably air-conditioned )- Offer fluids : Water and juice are best Avoid alcohol and caffeine- Sponge the person off with cool water - Have the person take a bath or shower- Encourage the victim to lie down and rest in a cool place.

For heat stroke, seek emergency medicalassistance immediately.


Hyperthermia Treatment


Well the air conditioning already on it’s lowest setting.You should try jogging in your lunchbreak to war up…

Hyperthermia

Humans do not tolerateheat exposure very well.

Once heat illness has occurred,it can rapidly become life-threatening.

How to prevent heat-related illnesses ?


1. Avoid dehydration

- Drink 1 pint of liquid 10 to 15 minutes before beginning vigorous exercise. - Drink at least 1 pint to 1 quart of liquid with adequate electrolyte supplementation each hour during heavy exercise with sweating in a hot climate. - Persons outdoors should consume at least 3 quarts of fluid each day to replenish fluid lost through urination, exhaled moisture, skin evaporation, and defecation. With moderate activity, increase to at least 4 to 5 quarts.

Hyperthermia : Prevention


2. Avoid coffee, tea, and alcohol - containing beverages. They cause increased fluid loss throughexcessive urination (diuretic effect).



3. Sodium an damp ; potassium supplements - You may supplement the normal daily diet during times of extreme sweating (greater than 1/2 to 1 quart per hour) with 5 to 10 grams of sodium (normal daily dietary intake is 4 to 6 grams. Most adults would be fine with 1 to 3 grams) and 2 to 4 grams of potassium. - Supplemental salt is advised when weight loss from sweating exceeds 5 pounds in a single session, particularly early in the acclimatization period when salt losses in sweat are great.



http://encarta.msn.com/find/Concise.asp?ti=05964000

3. Sodium an damp ; potassium supplements - Consume 1/2 gram (1/10 teaspoon) of sodium chloride (table salt) with a pint of water for each pound of weight loss over 5 pounds.

- Eat potassium-rich vegetables and fruits, such as broccoli and bananas.



4. Wear appropriate clothing

- Dress in lightweight, absorbent layers so that clothing can be added or shed as necessary.

Wear a loosely fitted, broad-brimmed hat.



5. Towel off the face and scalp frequently

- As 50% of sweating occurs from these areas, remove headgear when possible in order to allow evaporation from the head.



6. Keep out of the sun on a hot day

- Resting on hot ground increases heat stress.



7. Encourage rests and fluid breaks

- Insufficient rest contributes to an increased risk for heat illness.



8. Condition yourself for the environment

- Gradual increased exposure to work in a hot environment for a minimum of an hour a day for a period of 10 days will allow you to acclimatize.

More time spent in the heat hastens the process.

Obesity and lack of conditioning contribute to an increased risk for heat illness.



9. Be watchful of the very young and very old

- Their bodies do not regulate body temperature well and can rapidly become too hot or too cold.



http://www.100percentdrugfree.org/page01.htm

10. Avoid taking drugs that inhibit the sweating process :

- Atropine, antispasmodics, anti-motion sickness, diminish cardiac output

- Beta blockers disrupt certain features of physiologic activity - Antidepressants, antihistamines increase muscle activity - Hallucinogens, cocaine or

- Diuretics that promote dehydration.




The best ways to beat the heat areto avoid going outside and drink plenty of fluids.


NON

Documents

Seafarer’s Health : Risk Factors Operational factors which can degrade crew performance Temperature Ships in Service Training Material A-M CHAUVEL