Electrocution.conduite a tenir devant un accident électrique.ماذا يجب عمله عند وقوع حادث كهربائي.
Published on: jeudi 24 avril 2014 //
Infirmier polyvalent 2ème année
conduite a tenir devant un accident électrique
I) - IntroductionWhen an accident happens to you , like a car accident , drowning , electric shock or other serious event, you should as far as possible provide your help to cure or take the person to deal in trouble : it is an obligation moral as well as legal , it is mandatory to rescue a person in distress, under penalty of a conviction for " failure to assist a person in danger ." But good intentions are not enough, it is often even more dangerous than no intervention. This is why it is essential to know the basics of first aid and apply them in a logical order : first of all , we must protect the injured and alert the rescue.
II) - DEFINITION
- Electrocution : means death due to electrocution . It is the passage of electric current through the body is likely to cause many problems , whose severity depends in part on its intensity .
- Electrostatic : refers to the various pathophysiological events due to the passage of electric current through the human body.
conduite a tenir devant un accident électrique
III) - GENERAL
1) - Accidents at low voltage : 220-380 Volts
- Victims : children and handymen
- Danger of bathroom
2) - Accidents high voltage electricians , contacts with the subway tracks ... etc.
3) - Natural Electricity
Animals: Gymnote , electric fish syncope swimmers and drowning
Lightning : In a few milliseconds , a lightning discharge stream 10 000 to 25 000 amperes under a voltage of 10 to 100 million volts .
Sudden heating of air to 30,000 ° C in a micro- second explosion .
4) - Electricity for medical use : equipment operating theaters , endoscopy, intensive care unit can electrocute medical, paramedical and especially patients carrying a endocavity probe or a central catheter. Three types of devices are involved :
Defibrillators :
doctor / bed touch
the burned patient skin
Electric Scalpels : use less dangerous bipolar scalpels .
electric syringe connected to a central catheter which can lead directly to the current infarction
IV) - EFFECTS ON THE BODY
Electric current can cause muscle contractures , which become invincible beyond a certain level . These contractions tend to set the person at the power source , because the muscles that flex the fingers are stronger than those who extend .
More serious are the effects on the heart and respiration. There may be in fact a contraction of the respiratory muscles causing respiratory arrest , reversible after discontinuation of current and artificial respiration. On the other hand, if the current path through the heart , it can upset and do " fibrillate ": in this case, the contractions become extremely fast , chaotic and inefficient ( Cardiac dysrhythmia ) . The wounded therefore likely to die from respiratory failure or heart failure . Finally , the electric current causes superficial or deep burns.
V) - PATHOPHYSIOLOGY
A - EFFECTS OF ELECTRIC CURRENT: 2 TYPES OF EFFECTS
stimulation / inhibition of cellular electrical phenomena .
- Asphyxiation by muscle contractures : current of 20 milliamps through the rib cage and respiratory muscles tetanizing . This tetanisation yields to break contact with the electric current.
- Circulatory stop by asystole or ventricular fibrillation. The current flows through the heart : major risk with currents from 50 milliamps and especially with the AC .
- Disorders of consciousness and autonomic . A current of 2 amps inhibits nerve structures (contact with the head) : coma, respiratory arrest autonomic disorders which may be delayed several hours.
Electrical burns : two mechanisms sometimes associated .
- Burn flash and arc : no current passes through the body and the electrical energy is converted into heat energy outside the body . Burn the exposed parts (hand, face). The temperature reached high voltage is around 2500 ° C. Note the severity of ocular arc flash can cause delayed a few months cataract : hence the need for an initial declaration of accident.
- Burns electro . The current passes through the body and burns Joule " amps kill joules burn ."
- Oral burn the child sucks a power outlet obstruction of the airways to death.
- Deep burns , extended in healthy skin : rhabdomyolysis (the destruction of skeletal or voluntary muscle as seen during the crush syndrome ( muscle crush syndrome) among other muscle. ) . Muscular and nervous axes ( low resistance electric) are particularly vulnerable . Thrombosis of small vessels , tissue necrosis .
B - FACTORS AFFECTING THE IMPORTANCE OF ELECTRICAL DAMAGE.
- Three factors are related to current : type current and voltage
- Factors related to the topic
The overall resistance to current flow varies :
- Moisture at point of
- The resistance of the body : the human body behaves as a conductive core (nerves , vessels, muscles) , wrapped in an insulating bark skin . The insulating skin is that if it is dry . Beyond 1000 volts there is electrical breakdown of the skin and thus reduced protection .
Note the role of supporting medical equipment (sensors, central venous ) for conducting current directly to the heart .
- Electrical insulation : represented by clothes, shoes, soil carpet isolated.
So danger of electrocution in bathrooms where the subject is in a situation of minimal resistance. ( Naked and wet subject)
Driving current
- Long at risk of cardiac arrest ( hand - hand, head - feet) deep electrothermal burns.
- Short : Child putting two fingers in making deep burns, localized disabling.
Contact time
- Extended by muscle contractions sticking victim driver
- Short : in case of spillage, loss of consciousness or if a power failure
VI) - CLINICAL STUDY :
life-threatening injuries
1) - circulatory distress: two mechanisms
myocardial disease: ventricular fibrillation, coronary thrombosis . Judgments may be delayed a few hours hence need for monitoring .
fetal death during the mild electrification of the pregnant woman .
depletion: internal bleeding in two ( fall eschar )
external bleeding projection (lightning) to vasoplegia spinal trauma , collapse.
2) - respiratory distress .
- Ventilation : stunning respiratory centers
- Fracture of the cervical spine
- Airway obstruction : burning mouth in children
- Tetanisation respiratory muscles
- Other: bronchial perforation , pneumothorax.
lesions involving the functional prognosis
- Neurological sequelae :
- Encephalic : hemiplegia, seizure disorders ...
- SCI : destruction of the bone , spine fracture, denervation of a limb, spinal artery thrombosis ( paraplegia, quadriplegia ) .
- Neurosensory sequelae
- Various visual disturbances
- Trauma: eardrum , hearing loss vertigo
- Psychological sequelae
- Insomnia, irritability
- Cardiovascular effects , trophic ( burns) , aesthetic, fractures, trauma.
VII) - ACTION TO BE TAKEN
1 ) - In all cases :
TURN OFF POWER :
The human body is electrically conductive , do not touch the victim of electrocution without first shutting off the power ( switch or counter) or without the victim away from the power source using an object nonconductive (stick , plastic brooms , ... ) . In cases where the accident is due to a current of very high intensity ( power line for example) you must maintain a distance of at least 20 meters from the victim. Mobilize with caution , respecting the axis head - neck-torso because of the risk of associated lesions.
OR MAKE ALERT ALERT THE AID
TREAT THE VICTIM :
Loosen the collar, tie and belt the victim.
If the victim remained conscious monitor his condition until help arrives .
If the victim is unconscious but breathing , place in recovery position (see Appendix) and then monitor his condition until help arrives .
If the victim is not breathing, give mouth-to- mouth and heart massage.
In all cases , it is preferable that the victim was examined by a doctor , because the electric current may have caused internal burns.
NB) - There is another gesture , which may sometimes restore heartbeat , if they do exist at all , and if this movement is performed rapidly . This is the " precordial blow " forcefully hit the chest of the electrocuted , a fist under the left breast. If after this action, the show beats normally , cardiac massage is not necessary . It will nevertheless regularly monitor the pulse and continue , if necessary, mouth to mouth , waiting for specialized help.
SOME BASIC PRECAUTIONS :
- Avoid DIY and fixtures fortune on electrical installations.
- Do not use electrical appliances with wet hands or feet in the bath or shower .
- Do not spray water on electrical installations and devices.
- Avoid Strip and flexible connections . Do not let them turned on.
- Protect outlets in the presence of children.
- Use of standard hardware .
- Please ensure your check the efficiency of landings .
2) - electrified seemingly unscathed
- Secondary aggravation is always possible : ECG monitoring for 24 hours and transfer emergency because of the risk of cardiac arrhythmias during transportation.
- All pregnant women should undergo electrified maternal and fetal monitoring (maternity ) .
- Coup d' arc eye , cervical or cephalic : declaration of accident, regular ophthalmic examinations oriented screening for cataracts.
3) - electrified serious
- Cardiac arrest Heart Massage External ( MCE ) , mouth to mouth, suspecting principle of a spine injury .
- Defibrillation , intubation, ventilation ...
- Medical treatment of burns : infusion of crystalloid solution
- Monitoring : state of consciousness, blood pressure, pulse , urine output , ECG.
- Salvage surgery : fasciotomy decompression when compressive edema, excisions, amputations ...
VIII) - CONCLUSION :
o Compliance with safety standards set by ONE.
o Preventive Action at children.
Thousands of people each year are victims of electrification (burns and shock ) or a real shock can cause death by cardiac arrest.
For electrical installation , follow the safety rules set out below .
Keep in mind that it is not necessary for a device works for it to be the cause of an accident only if it is connected. You are not immune to electrocution because handling equipment "off" .
Ensure that your electrical installation complies with standards.
Make install circuit breakers " Differential high sensitivity" capable of interrupting the flow of current in case of a fall in intensity.
Use protected electrical plugs pins which do not conduct current along their whole length .
Always use appropriate extensions to the considered decision .
Do not overload outlets with multiple input devices , check the wattage they can support.
Do not use appliance if your hands are wet. ( To clean your refrigerator, it is recommended to unplug ) .
Also, do not forget that the increased risk of electric shock if the soil is conductive ( or tiled wet rooms) .
In the bathrooms , some precautions must be observed.
Do not use any electrical appliance in the shower or in the bath ( hair dryer, razor or phone ... ) .
above the bath or shower electrical devices are prohibited, with the exception of electric storage water heaters and fixtures with low voltage , Watertight .
less than 60 cm from the edge of the tub or shower , electrical appliances are allowed if they are protected by a differential protection device with high sensitivity 30 mA at most. All protected against water protection devices are marked with a logo
In the "outer" area , devices must bear the symbol of protection against water and be connected to the earth ( or fitted with double insulation ) .
Do not tinker with electrical installations if you do not have good knowledge on the subject, but instead make use of a true specialist, if possible, a professional electrician. It does not just happen electrician. However, if you feel able to do some work yourself , do not neglect safety rules that we recall below.
When you repair an appliance , unplug it.
Before working on an electrical circuit, turn off the power at the circuit breaker .
Check with a circuit tester that the current does not pass through the son that you handle .
If you connect , use the appropriate section son .
Never replace a blown fuse with a fuse of a higher rating .