Chapter 45. Nuclear and radiation incidents
In the emergency response to an incident involving radioactivity, the principles of casualty care remain the same:
• Rapid assessment
• Administration of life-saving procedures
• Stabilisation
• Evacuation.
All of these procedures should be carried out without risking the safety and health of the paramedic team who must be sure that they are not placing themselves or the casualty at unnecessary risk – or that the risk is acceptable.
The hazards to which paramedics may be exposed are:
• Penetrating radiation
• Contamination.
Ionising radiation cannot be detected by the human senses but at the levels likely to be encountered in plausible accidents, there is little risk, and simple precautions will promote safe management of the radiological aspects of the injury.
The hazards
Radioactive sources are widely used in the UK, in:
• Industry
• Hospitals
• Further education establishments
• Nuclear power stations
• Research establishments
• Military bases
• During transport (air, road, sea and rail).
Where radioactive materials are processed on a large nuclear site, there will be contingency plans in the event of an accident, which may require the support of ambulance, fire and local authority agencies as well as the employer’s own response team.
Substances are said to be radioactive when they give off radiation
Types of radiation
α-Radiation
Alpha particles travel a very short distance in air and are stopped by a sheet of paper, clothing, blood or dressings. Ingestion or inhalation must be avoided as the particles can damage more sensitive internal organs. Examples of substances that emit α particles are uranium, plutonium and radon.
β-Radiation
β-Radiation is stopped by a thin sheet of aluminium or heavier clothing. It can penetrate the skin surface and therefore damage the epidermis and dermis to produce radiation burns. The hazard is greatest when the β emitter is in direct contact with the skin. Examples are iodine and tritium.
γ-Radiation, X-rays and neutrons
γ-Rays, X-rays and neutrons all travel great distances in air and are only stopped by thick concrete or lead. These forms of radiation can pass through the body, depositing energy and causing damage as they proceed. They are therefore still a hazard at some distance from the casualty or incident. Examples are industrial radiography sources, caesium and cobalt.
Risks of exposure
Ionising radiation can affect a part of the body or the whole body, causing localised effects (radiation burns) or systemic effects (radiation syndrome).
Loose particles of radioactive material (dust, aerosol or liquid) are known as contamination.
The material will emit radioactivity but in addition, it can easily be inhaled or ingested and precautions are needed to prevent this.
There are three scenarios involving exposure to radioactive materials that the paramedic will have to consider in the immediate care situation:
• The exposure to γ-rays or X-rays from a source near to the patient
• The presence or spread of contamination onto skin, hair and clothes of the patient
• The inhalation or ingestion of contamination by the paramedic or patient during rescue, resuscitation and removal.
In each case, simple precautions can be taken to reduce the risk to paramedic personnel and patients.
There may be useful clues available, such as a radiation identification mark on the package or vehicle, bystander knowledge or an unusual military or police presence.
Remember:
• Any radiation dose to the attendants is likely to be small
• Simple precautions will reduce risk to personnel.
The principles of ABC (airway, breathing and circulation) still apply and must not be delayed on account of possible radiation exposure.
Patient overexposure to penetrating radiation
A patient who has been exposed to a large dose of penetrating radiation is not radioactive (just as patients who have had a clinical X-ray are not radioactive) and therefore presents no hazard to the medical personnel. Such an incident may arise with exposure to an industrial radiography source.
External contamination
If there has been a spread of radioactive materials, then the patient may be contaminated; this contamination may present a hazard to the patient and the paramedic, so it has to be dealt with safely. Most of the contamination is likely to be on the patient’s clothes.
Internal contamination
There may have been a release of radioactivity which the patient has inadvertently swallowed, inhaled or absorbed through the skin, e.g. if the casualty has been exposed to smoke in a fire involving radioactive substances. Simple procedures can be used to protect both paramedic and patient.
Contaminated wounds
Treatment of the injury and associated bleeding is of prime importance, but care must be taken to avoid spread of contamination around the site of the wound.
Dealing with an incident
In order to reduce potential exposure to external penetrating radiation and reduce contamination, some simple procedures need to be followed.
• Assess the risks from other hazards, e.g. buildings, traffic, smoke or chemicals
• Position the ambulance upwind from the accident site
• Carry out the initial survey, check ABC, institute immediate care and prepare the patient for movement
• Assume contamination is present and reduce the risk of self-contamination by following the guidelines below
• Keep the time at the accident scene to a minimum.
If there is a continued risk from radiation exposure the patient should, after resuscitation, be moved away 10 metres from the source to reduce the dose to an acceptable level. If this is not possible, paramedics or other ambulance staff can take it in turns to monitor the patient, thereby sharing any radiation dose. Preferably, an attempt should be made to reduce the level of radioactivity coming from the source. This is known as shielding and can be achieved by using lead or concrete but if these materials are not available then rubble, heavy stones, sand or earth can be used.
Protection
It is quite possible that personnel will have no prior knowledge of the presence of radioactive materials, but simple precautions of the type used against chemical or biological hazards will help to reduce the spread of contamination and subsequent risk to personnel.
• Always assume that contamination is present when dealing with a casualty affected by an incident involving radioactivity
• Wear a simple surgical face mask and gloves. This will prevent spread of contamination to hands and face. If the clinical condition permits, a face mask can be placed on the patient
• Keep disturbance of the area to a minimum as this reduces the likelihood of air-borne contamination. This should not interfere with resuscitation and other emergency procedures
• Cover open wounds with simple dressings. This prevents contamination entering wounds or contaminated blood spreading from the wound onto surrounding skin
• Remove external clothing (leaving underwear) carefully, if practicable, and place in large, sealable plastic bags. Wrap the patient in a blanket or contamination control envelope, as this helps to prevent spread of radioactive materials
• Do not eat, drink or smoke until checked for contamination by medical physics personnel.
Management of patients
Overexposure to penetrating radiation is unlikely to result in any specific symptoms and other injuries will dictate the management.
• The onset of nausea or vomiting may indicate a significant overexposure and the accurate recording of the time of onset is important for future hospital management
• Erythema may be visible on exposed skin and its distribution should be noted.
A list of hospitals in the area prepared to accept contaminated casualties should be available to the paramedic. The clinical condition of the patient may make it necessary to go to the nearest Emergency Department and then it is essential that warning is given so that suitable preparations can be made.
Movement in the ambulance should be kept to a minimum and staff can expect to be directed to a specific parking area for unloading, where they should remain until screened for contamination, a task likely to be undertaken by medical physics personnel.
It is recommended that the patient be placed in a contamination control envelope, thereby allowing containment of any residual contamination on the patient while permitting observation of wounds, dressings, skin colour and bruising.
Rapid onset of nausea or vomiting or the presence of erythema suggest significant radiation exposure.
Radiation advice
The police will be able to give information on the availability of hospital advice on irradiated or contaminated casualties under the National Arrangements for Incidents Involving Radioactivity (NAIR). The NAIR scheme is coordinated by the National Radiation Protection Board (NRPB) to provide advice in the event of a nuclear incident if advice from major plant operators ( British Nuclear Fuels Ltd, Scottish Nuclear and Nuclear Electric) is unavailable.
Follow-up
After the patient has been transferred to hospital, it may be discovered that the emergency personnel are contaminated with radiation. Decontamination is a simple process, but may need to be carried out in a special area. This could cause concern to some individuals and requires explanation:
• Contaminated clothing is identified and discarded in sealable bags
• All clothing is then removed
• Monitoring is carried out by medical physics personnel using radiation monitors (Geiger counters)
• Areas of skin contamination are identified by skin markers
• Decontamination is carried out by washing with soap and water
• Areas of contamination that are difficult to remove will require a mild abrasive such as dry soap powder or industrial skin cleanser
• Continued cleansing of the skin must be done with care to avoid inflammation
• If air-borne spread is a possibility then it is necessary to check for inhalation and this is normally done by checking counts on nasal swabs or nose blows
• Personnel will be asked to produce biological samples (faeces and urine) which will be monitored for radioactive substances.
Antidotes
If it is suspected that any intake has occurred, it is unlikely to require treatment, but therapy does exist and has been used for many radioactive substances; examples are: diethylenetriaminepentaacetic acid (DTPA) for plutonium exposure; Prussian blue for caesium exposure and potassium iodate for iodine exposure.
For further information, see Ch. 45 in Emergency Care: A Textbook for Paramedics.
