Advanced Resuscitation Techniques

Terminology Arrhythmia – an abnormal rhythm of the heart

Perfused – the passage of a fluid through the vessels of a specific organ or tissue

Occlude – to obstruct the path. Also used to describe blocking the vent on a suction catheter used with an oxygen or electric powered device, which then ensures that air is drawn through the end of the catheter, creating the suction

Stress – a disturbing physiological or psychological influence which produces a state of severe tension in an individual

Agonal respirations – intermittent gasps from a casualty who is unresponsive. Agonal respirations are not classed as normal breathing.

Vital signs

ADULT NORMAL ABNORMALPulse 60-100 beats per minute <60 or >100 beats per minuteBreathing 12-20 breaths per minute >20 breaths per minuteSkin (colour and temperature)

Warm and pink Cool or hot, pale, moist, flushed/red, blue/cyanosed

Conscious state Alert and orientated Drowsy or unconscious

Advanced Resuscitation and Oxygen Administration

The breathing processFor air to move into and out of the lungs, a pressure differential must be generated. Changes in air pressure are produced by contraction and relaxation of the intercostal muscles and the diaphragm.

Breathing In Diaphragm contracts, the ribs move up and out, increasing the volume of the chest. The pressure

inside the thoracic cavity drops and air is forced into the lungs.

Breathing Out Diaphragm relaxes, the ribs move down and in. The chest returns to its original volume and air is

forced out of the lungs.

The average adult takes about 12-15 breaths per minute. The average amount of air inhaled and exhaled is about 500 ml (a normal breath). In infants the normal breathing rate can be between 25-50 breaths per minute.

Respiratory noisesIn a healthy person there should be no audible sound as they breathe in and out. Where a casualty has some respiratory distress, this may be accompanied by noises. A casualty in severe respiratory distress may make no sound at all. Cough - a sudden expulsion of air from the lungs (with a characteristic noise), may be associated

with mild airway obstructions, or inflammation of the upper and/or lower airways

Wheeze - a whistling sound when breathing in or out, most commonly encountered by first aiders treating casualties with asthma and may also be associated with other chronic obstructive airways diseases

Stridor - a louder or harsher sound than a wheeze, may be associated with a partial airway obstruction

Gurgling - a broken irregular sound similar to moving water may be associated with fluid or mucus in the lower airways

No sound - no vocal sound, even with a casualty showing an effort to breathe. A casualty with a complete airway obstruction may make no sound, the effort to breathe may also take in the use of accessory muscles.

First aid conditions which require additional oxygenThe body requires a constant supply of oxygen and when it does not receive enough, hypoxia results. Hypoxia results from less-than-normal oxygen content in the organs and tissues of the body and causes impairment of their function. It is essential to be able to recognise breathing difficulties and to provide immediate first aid including supplementary oxygen to treat the casualty.

Respiratory distress or hypoxia can be caused by: Airway obstruction, such as:

– foreign material or vomit– tissue swelling (allergic reaction)– incorrect head position during unconsciousness (eg: a casualty slumped forward after a car crash)

Trauma (head injury) Drugs Near drowning Asthma Impairment of nerves and/or muscles of breathing

– spinal cord damage– chest injuries– some poisons and venom

HypoventilationHypoventilation is breathing that is not adequate to meet the needs of the body (too shallow or too slow), or reduced lung function. The rate and depth of breathing are more than is necessary to maintain a normal level of carbon dioxide in the blood. The carbon dioxide level rises, leading to inadequate oxygen in the blood.

As hyperventilation does not cause a lack of oxygen, the casualty should not be administered oxygen therapy in this situation.

Management of hyperventilation DRSABCD Reassure the casualty Remove the casualty from the environment contributing to the over-breathing Encourage the casualty to breathe normally by having them copy you as you breathe in through

your nose and out through your mouth Seek medical aid - call 000 for an ambulance if required.

AsthmaAsthma is an allergic reaction resulting in the narrowing of the smaller airways. This narrowing is brought about by three mechanisms:

Acute narrowing and spasm of small air passages Swelling of the airway lining Secretion of mucus in the airway

“Preventer” medications, taken daily, act to prevent the swelling and mucus secretion. “Reliever” medications are taken to open the small airways in the event of an asthma attack.

All blue reliever puffers are safe, when used as directed. The student may experience harmless side effects such as shakiness, headache, a tremor or a ‘racing’ heart.

Management if responsive: If a severe attack call 000 immediately Reassure patient and assist them into a comfortable position Administer oxygen therapy Prepare the inhaler

– Check with casualty for correctness of inhaler– Shake the blue reliever puffer and remove the cap– Insert the puffer into the spacer, ensuring that the casualty places their mouth over the

mouthpiece and gets a good seal Demonstrate 4 x 4 x 4 technique

– Give 4 separate puffs, breathing each puff 4 times – Wait 4 minutes before repeating if ineffective.

CPR may be required if the casualty becomes unconscious.

In a severe attack, 6-8 puffs may be given to an adult every 5 minutes Even if medication appears to be effective, medical advice should be sought

Management if unresponsive: Call 000 urgently Conduct Primary Survey and act accordingly

Chronic Obstructive Airways Diseases (COAD)Chronic Obstructive Airways Diseases (COAD) include emphysema, chronic bronchitis and other

Mild Cases More Severe Very SevereCough Pale ExhaustionRapid breathing Distressed, anxious Altered responsivenessWheeze Fighting for breath Cyanosis (blueness)Rapid pulse Aspiratory / Expiratory wheeze Difficulty / unable to speakChest tightness Severe chest tightness No wheeze at all

airways diseases. Coad is an ongoing illness, the casualty will be aware of their condition and, subject to having enough breath to speak, will be able to tell you of their condition.

In healthy people, high carbon dioxide levels are a stimulus to breathe. COAD casualties, who chronically have high carbon dioxide levels, loose this reflex and instead their breathing control centre relies on low levels of oxygen in their body to stimulate them to breathe.

Due to their body relying on low levels of oxygen to stimulate breathing, casualties with COAD are normally treated with low levels of oxygen (eg: two litres per minute). If the higher concentrations of oxygen commonly available in first responder oxygen equipment (8 litres per minute or more) are used to treat a COAD casualty it may cause them to under breathe.

Management of COAD DRSABCD Reassure the casualty Provide oxygen therapy, with the casualty sitting in an upright position Continually monitor response, airway and breathing and commence CPR if the casualty is

unresponsive and not breathing normally. Seek medical aid - call 000 for an ambulance if required. Do not leave the casualty unattended, especially if receiving oxygen. Document observations in order to identify trends.

Oxygen AdministrationOxygen is a colourless, odourless, tasteless gas that is essential for the body to function properly and to survive. The air that we breathe in contains approximately 21% oxygen, and the heart relies on

oxygen to pump blood. If not enough oxygen is circulating in the blood, it is difficult for the tissues of the heart to keep pumping. Supplemental oxygen is used to treat medical conditions in which the tissues of the body do not have enough oxygen.

Oxygen for medical useMedical oxygen is stored under pressure in steel or aluminium cylinders. These cylinders can be identified by the following features:

Australian standard pin index valve for oxygen equipment All white bottle Cylinder should be labelled “medical oxygen”

Common cylinder sizes are:o ’B’ - 200 litres when fullo ‘C’ - 400-490 litres when full

50 minutes, with continuous use of oxygen therapy at 8 litres per minute 30 minutes, with continuous use of airbag (and oxygen) at 14-15 litres per minute

o ‘D’- 1500 litres when fullo ‘G’- 7600 litres when full

The components of oxygen resuscitation equipment

*Medical oxygen cylinders are all white.

Preparing a cylinder for use Check the external condition and colour of the cylinder Check the valve and outlet port, and wipe them clean Remove the plastic stopper or tape, and check for moisture in the outlet port Point the cylinder away from you and ‘crack’ the valve for one second Ensure the valve is turned off tightly

Administering oxygen therapyOxygen therapy is a treatment that provides extra oxygen to the tissues of the body through the lungs, and is provided to a casualty as a supplement to normal respirations. Oxygen therapy provides a regulated flow of supplementary oxygen to ‘build up’ to the necessary level. Oxygen therapy is

usually delivered by a face mask, but nasal prongs can also be used.

Conditions that may require Oxygen TherapyOxygen can be administered to a patient where there is a risk of Hypoxia or a compromise in the availability of a normal oxygen supply. Some examples are:

Difficulty breathing Unconsciousness Shock Blood loss Chest pain Shortness of breath, including asthma Severe pain Circulatory distress Fractures Fainting

If a conscious casualty does not want to use the mask, they can hold the mask in front of their face, or remove the tubing from it and direct the oxygen flow around the mouth and nose.

Mouth-to-mask resuscitation with oxygenResearch has shown that adding oxygen during mouth to mask resuscitation can increase the oxygen received by the casualty from 16% to 50%.

Oxygen is turned to the appropriate setting and the tubing fitted either to the oxygen port, through the opening of the mask, or between the cheek and the mask if an adequate seal is maintained. Masks with ports are highly recommended for this procedure.

Oxygen and airbag resuscitation

The airbag resuscitator with oxygen reservoir is a manually operated, soft-recoil silicone bag with a secondary bag attached. This secondary bag acts as a reservoir for oxygen when connected to an external oxygen supply.

The resuscitator with oxygen reservoir will provide the casualty with up to 95% oxygen when connected to an oxygen supply, with a flow rate of 14-15 litres per minute.

The disadvantage of these devices is that care must be taken to continually assess the casualty. It is easy to inflate the casualty’s stomach, or to cause exacerbation to chest and lung injuries or conditions.

Using oxygen and airbag during resuscitation Setting up the airbag Check:

– the correct operation of the patient valve– the valve to the oxygen reservoir bag

– the connection to the oxygen supply Turn oxygen on to 14-15 litres per minute to allow inflation of the airbag reservoir When the reservoir bag is inflated, compress the airbag to expel any air from the unit. This should

then leave the airbag with 100% oxygen

Operating the airbag Position the casualty valve in the resuscitation mask Compress the airbag with two hands (for an adult) using a gentle squeezing motion, taking at least

1.5 – 2 seconds for the chest to rise. o The amount of oxygen to be forced into the casualty’s chest is the amount required to

make the chest rise. Release the airbag and allow it to refill ready for the next ventilation

If the oxygen bottle is depleted during resuscitation, continue to use the airbag resuscitator equipment and remove the reservoir bag.

NOTEThe rescue breathing operator controls the backward head tilt and ensures a proper seal between the mask and the casualty’s faceThe rise and fall of the casualty’s chest should be watched at all times during this procedure.if at any time, either operator is not happy with the functioning of the oxygen equipment, the equipment must be removed immediately and rescue breathing must continue by the mouth-to-mask, mouth-to-mouth or mouth-to-nose method.

Children and Oxygen Resuscitation:If oxygen equipment is being used on a child, the paediatric airbag (if available) should be used and compressed with one hand. When the child’s chest is seen to rise, stop compression of the bag.

Airbag resuscitators not specifically manufactured for the exclusive use on infants should not be used on infants.

Airbag checksTo ensure the airbag is ready for use: Check the airbag for leaks and direction of airflow by:

– blocking the patient valve with the thumb or hand and compressing the bag under reasonable pressure– checking that air does not leak out of the rear valve, the bag or the casualty valve– releasing the thumb or hand, when the bag should compress and refill rapidly

Check the function of the yellow disc membrane on the patient valve by:– placing the oxygen reservoir bag over the casualty valve and inflating it fully by squeezing the ventilation bag– squeezing the reservoir bag gently. The yellow disc membrane will lift (during resuscitation, the casualty exhales

through this disc membrane) Check the overflow valve of the oxygen reservoir by:

– inflating the reservoir bag as described above and connecting it to the reservoir valve– compressing the reservoir bag rapidly and watching the disc in the valve lift (this membrane ensures that the

reservoir bag cannot be overfilled with oxygen) Check the air-intake membrane which is located in the rear valve of the airbag by:

– checking its function by inflating the reservoir bag as described above and connecting it to the airbag– repeatedly compressing the airbag. The reservoir bag will empty and the airbag will draw in air through the air-

intake membrane.

Flow rates for oxygen therapy and resuscitation

ResuscitationMethod Flow rate O2 concentration

Mouth to mask Expired air 16%

Mouth to mask (with O2) 8 LPM 50%

Mouth to mask (with O2) 15 LPM 70%

Bag valve mask (O2, no reservoir) 15 LPM 50%

Bag valve mask (O2 plus reservoir) 15 LPM98%

Bag valve mask (no O2) Normal air 21%

Oxygen Therapy

Therapy Mask 8 LPM 50%

Equipment maintenance General care

o the machine should be kept clean and free of sand and foreign materialso to ensure its correct operation, equipment must be checked before starting operational duties (eg patrol) each day

and after any use (including training sessions)o whenever the oxygen equipment shows defects that may cause it to operate incorrectly, the machine must be

taken out of service immediately and repaired by the manufacturer

o

Care after useAfter every use, the resuscitator should be disassembled, cleaned, disinfected, reassembled and tested in an orderly sequence by:

o sending oxygen therapy masks to hospital with the casualty or disposing of them after useo washing the resuscitation masks thoroughly in warm soapy water so that all foreign material is removed, then

rinsing them with fresh running watero disassembling and washing the casualty valve and the rear valve in warm soapy water, then rinsing them in fresh

running water and reassembling themo washing the airbag in warm soapy water, then rinsing it in fresh running watero washing the reservoir valve (on the Laerdal bag) and oxygen reservoir in warm soapy water, then rinsing them in

fresh running watero soaking all contaminated parts in a solution of 70% alcoholic chlorhexidine or a hypochlorite solution (bleach)

for at least two minutes, then rinsing and drying themo testing all parts of the equipment after drying and before storage to ensure that the equipment is ready for use the

next time it is needed.

Routine check of equipmentOxygen equipmentTo ensure that oxygen equipment is ready for use:

check the oxygen tubing for cracks or other damage. Ensure that the open end will fit easily to both therapy masks, as well as the oxygen nipple of the airbag

check the flow of oxygen from the cylinder through the tubing check that there is no odor from the oxygen being expelled from the tubing check the airbag close the cylinder valve, and then drain oxygen from the system by operating the delivery system (where the unit

has two ensure both are operated) and check that the needle on the contents gauge falls to zero mark the cylinder with the contents, time and date of inspection.

Ancillary equipmentTo ensure that ancillary equipment is ready for use: check both therapy masks for cleanliness and serviceability check the condition of the resuscitation mask cuffs for fit, perishing or cracks ensure that a minimum of two larger (adult) size oropharyngeal airways are present and sealed in their original

packaging check in the case for:

– chalk, for marking the amount of oxygen in the cylinder– pens, pencils and paper for keeping records– gloves, for personal protection during emergency care– spare sealing washers, to replace defective or missing seals, as required.

Storing oxygen equipmentCylinder should be kept cool, dry and under coverAll cylinders should be kept in a secure but accessible area near the oxygen equipmentCylinders should be contained or secured to prevent movement and precautions should be taken to prevent them falling over (store upright)The storage area should be out of direct sunlight and away from heat

Cylinders should be kept in a ventilated space - any leakage in an enclosed space could cause an increased concentration of oxygen which could be dangerous in the event of a fireCylinders should be stored without any pressure in the system - turn off the cylinder then drain oxygen from the system by operating the delivery systemDo not store near grease or oilFull and empty cylinders should be clearly marked and kept stored separatelyThe storage area should have regulation signageThere should be no naked flames or smoking allowed within 25 metres of stored oxygen cylindersEmpty cylinders should be returned for filling without delay

Material Safety Data Sheets (MSDS)Your club or service should have a Material Safety Data Sheet for each hazardous substance stored on the premises. These may be stored in a central folder or each sheet may be stored with the hazardous substance. Material safety data sheets contain information on how the substance should be stored and what to do if poisoning occurs.

Safety with oxygen Always check that the cylinder is clean Never use oxygen near an open flame Never use oxygen near cigarettes Never use grease or oil with oxygen equipment Never use oxygen when delivering a shock via a defibrillator Don’t drop or roll cylinders Store cylinders upright and secure them Store full and empty cylinders separately. Mark empty cylinders clearly Don’t completely empty a cylinder – leave pressure in the cylinder to prevent moisture entering

Oropharyngeal Airways Oropharyngeal (OP) airways are curved plastic devices that help keep the

airway clear in the unconscious casualty by depressing the tongue and keeping the teeth and lips apart.

The OP airway by itself does not replace correct airway management practices and should be considered only as a tool to assist in the

blocked by the tongue (top) and using an OP airway to assist with a clear airway (bottom)

management of a casualty’s airway. OP airways must only be used on unconscious casualties who do not have a gag reflex

Care of OP airwaysOP airways must be kept in their original packaging. They should be easily accessible in the first aid kit, oxygen unit and first aid rooms. OP airways packaging should be checked to ensure that it has not been opened and is still intact.

After use on a casualty, the contaminated OP airway should be disposed of in a safe manner, preferably in a clinical-waste bag provided by attending ambulance or medical personnel. If this is not possible, the contaminated OP airway should be placed in a clinical-waste bag and stored in a safe place until proper disposal can be organised.

When to insert an OP airway The use of an OP airway is optional. Ideally, the OP airway should be inserted into an unconscious casualty’s mouth after the casualty

has been rolled onto their side and their airway cleared. The airway can also be inserted during CPR while the casualty is on their back. In this case, stop

CPR and quickly insert the airway before continuing resuscitation.

OP airways should not be used: if the casualty is conscious or semi-conscious - insertion of an OP airway into a conscious

casualty may induce vomiting or gagging if an airway of the correct size is not available if there is a large amount of vomit if the casualty is under eight years of age

Choosing the appropriate-sized OP airway OP airways come in different sizes. To select the appropriate size, place OP airway on casualty’s outside cheek

and measure from: 1) Centre of lips to angle of jaw

The correct size keeps the tongue forward and maintains an open airway. The flange (top flattened end) of the airway will extend just past the centre

of the casualty’s lips. The correct sized airway is the one that reaches the angle of the casualty’s jaw.

The main risks of its use are: If the casualty has a gag reflex, they may vomit When it’s too large, it can close the glottis and thus close the airway Improper sizing can cause trauma to the throat and bleeding in the airway

OP airways are inserted using the ‘rotation’ method. This method is not recommended for infants or children under the age of eight because the roof of their mouth is still soft and easily damaged.

Inserting an OP airwayOnce the correct size airway is selected: Tilt the casualty’s head backwards Open the casualty’s mouth with one hand using jaw support or jaw thrust, if necessary

Clear airway using postural drainage, finger sweep and/ or suction Measure and choose an OP airway of the correct size Remove the OP airway from the packet and lubricate it, using moisture from the lips of the

casualty, or water Hold the OP airway by the flange and Insert OP airway by following steps 1, 2, 3:

1. With the tip pointing towards the roof of the casualty’s mouth, insert the airway to approximately one-third of its length

2. When one-third of the airway is inside the mouth, rotate it 180° until the tip points downwards, at the same time sliding it over the casualty’s tongue in one smooth movement into the back of the pharynx until the flange is touching the lips

3. It should slip easily into place. If it is difficult, stop and reposition the casualty’s lower jaw and tongue before trying again. Never force it into position.

NOTE:The OP airway should not be inserted during the delivery of external cardiac compressions, as this may impede the successful insertion of the airway and cause unnecessary injury.Do not force the OP airway into the mouth - it should slide in easily.Ensure the lower lip is not pinched between the casualty’s teeth and the OP airwayEnsure the OP airway does not push the tongue backwards and block the casualty’s airwayEnsure you have adequate head tilt before inserting the OP airway

Removing the OP airwayIf casualty starts to regain consciousness, cough, gag or vomit, remove OP airway immediately.

The OP airway can be removed easily by sliding it out of the mouth following its natural curve – no rotation necessary.

Dispose of in biohazard bag as it is a single use item. Do not attempt to rotate the airway on removal. It is unnecessary and may cause damage to the

mouth and throat.

SuctionClearing of a casualty’s airway can be achieved by using manual finger sweeps. However, if you have a unit available with suctioning capability, you may clear additional fluids from the upper airway by using the suction component of the unit.

• Point tip of OP airway toward the roof of casualty’s mouth. • Slide the airway towards back of throat.

• When tip reaches back of throat, rotate airway 180 degrees

• Advance the airway until the flange rests on the casualty’s lips • Ensure lower lip is not pinched between teeth and OP airway• Check breathing - look, listen, feel.• Maintain head tilt and jaw

Suction comes in three types: manual oxygen powered (vacuum bottle) battery (or electric) powered

Suction device componentsWhile there are many variations to suction devices based on the type and the manufacturer, there are four components common to most suction devices. These are:

Suction catheter: A plastic tube which is inserted into the casualty’s mouth to suction out any foreign material. Suction catheters are single use only and should be disposed of in clinical-waste containers.

Collection jar: Fluids and foreign material suctioned from the casualty are collected in the jar. Collection jars are usually single-use with the jar being disposed of along with the contents in clinical-waste containers.

Jar cap and connection port: The jar cap and connection port keeps the contents in the collection jar and includes the fittings to connect the suction catheter and the device which provides the suction power.

Suction device: The device which provides the suction power and is the suction pump handle in manual devices, oxygen equipment in oxygen powered devices or the electric pump in a battery or electric powered device.

Hypoxia caused by suctionHypoxia (lack of oxygen) is always a risk when suction is used. For this reason manual suction should be on for only 15 seconds at a time with a break for at least five seconds in between operations. This reduces the amount of oxygen taken from the casualty. Due to their constant suctioning action, powered suctioning devices should only be used for five seconds before a five second break.

Suction checks Ensure that the device is clean and that all components are available including:

o suction cathetero collection jaro collection jar capo suction tubing (if required)o suction device

Operate the manual suction device (or turn suction on for powered devices) Test for suction against thumb or finger by placing it over the vacuum port Return the suction device to the case in its original position.

Administering suctionTo remove mucus, fluid or blood from a casualty’s airway using suction, follow the steps outlined below:

1) Check the suction device for correct operation2) Select the catheter and remove it from the sealed packaging, leaving a contact point within the

wrapper3) Connect the suction catheter to the connection port (or tubing for powered suction devices)4) Completely remove catheter from wrapper 5) Measure the maximum length of insertion by placing the tip of the catheter at the corner of the

jaw and measuring to the centre of the lips. Mark this point with a finger. 6) Insert the catheter into the lower cheek of the casualty (in the lateral position), ensuring that the

catheter is inserted no further than the point marked by the operator’s finger7) Operate suction for no longer than 15 seconds with manual suction devices before a five

second break. (If using powered devices suction only for five seconds before a five second break).8) Rotate the catheter within the casualty’s lower cheek, ensuring that the action is smooth and

gentle, to prevent damage9) Dispose of the catheter in the appropriate manner.

Ensure that only two-thirds of the container is filled Put on gloves Do not operate manual suction during insertion

Post-use maintenance of the suction unito Dispose of disposable jars in a suitable mannero Reusable jars can be flushed with clean cold water and rinsed with antiseptic solutiono Ensure that all unit components are disassembled and thoroughly cleaned as per ARC guidelines.

Trouble shooting suctioningThere are a number of reasons why suction equipment can fail or not operate correctly. If experiencing problems, check the following:

– is the suction tubing blocked– is the contents bottle full or cracked– is the seal missing or perished– is the unit not turned on– is the oxygen supply exhausted (for oxygen powered units)– is the battery flat (if battery powered unit).

Heart RhythmsElectrocardiogram (ECG)The electrical impulses passing through the heart can be mapped on a graph called an electrocardiogram (ECG). When a person’s heart becomes stressed, changes can be seen in the ECG.

Sinus RhythmThe normal rhythm of a healthy heart is called sinus rhythm. An AED will not recommend a shock if it detects this rhythm in a casualty.

Ventricular Fibrillation• VF is the most common rhythm in cardiac arrest• The heart quivers but doesn’t pump• Most commonly associated with coronary artery disease and heart attack• VF lasts a few minutes before all electrical activity ceases (asystole)• VF is a shockable rhythm

Ventricular Tachycardia (VT)• VT occurs when the ventricles beat too fast to pump effectively (pulseless VT)• Rate varies however it is always faster than 100 bpm and generally slower than 200 bpm.• VT may progress to VF then asystole• VT is a shockable rhythm

Asystole• Asystole refers to the absence of electrical activity in the heart.• Asystole is a non-shockable heart rhythm

o AED can only correct the heart’s electrical activity, not create it from nothing• All electrical activity has ceased and survival is unlikely

Signs and symptoms of Ventricular Tachycardia include: fainting difficulty breathing or shortness of breath very rapid pulse or no pulse palpitations - the casualty may feel like their heart is racing light-headedness or dizziness

chest pain pale/grey skin colour sweating nausea.

Management of VT minor cases may spontaneously revert to normal sinus rhythm without treatment pulseless VT will require treatment with an AED.

Defibrillation & AEDsDefibrillation is the delivery of an electrical current to the heart to correct an ineffective irregular heartbeat. The electricity is delivered indirectly to the heart via the chest wall.

An AED is only to be attached to casualties who are unresponsive and not breathing normally.

A defibrillator depolarizes the heart muscle, terminates the abnormal rhythm, and allows normal sinus

rhythm to be re-established by the heart’s natural pacemaker. Effectively the process stops the heart. Once repolarisation has occurred, it is hoped that the heart’s normal electrical activity will resume. Defibrillation is the definitive treatment for Ventricular Fibrillation.

The delay to defibrillate is the most important factor in determining survival from cardiac arrest. For every minute without defibrillation, survival declines by 10%.

AEDs should only be used on unresponsive, non-breathing casualties.An AED can and should be used on pregnant casualties.In large-breasted individuals, place the left electrode pad lateral to or underneath the left breast.If the casualty has an artificial, implanted pacemaker, a scar and raised area will be seen just below the left or right collar bone. Position AED pads 8cms from the pacemaker unit and proceed as usual.AED batteries and pads have expiry dates.

Children and AEDs: Standard adult AEDs and pads are suitable for use in children older than 8 years. Ideally, for children 1 and 8 years, paediatric pads and an AED with a paediatric capability should

be used. Pads should be placed in the same way as an adult. If an AED does not have a paediatric mode or paediatric pads then the standard adult AED and

pads can be used. Ensure the pads do not touch each other on the child’s chest. This may require one pad to be

placed on the centre of the chest and the other on the back of chest between shoulder blades.

Defibrillator componentsA portable defibrillator of the type commonly used by first aiders consists of a case containing the base unit with single-use, self-adhesive electrode pads. In addition to the AED, the following accessories should be kept with the unit:• resuscitation masks (adult) • spare electrode pads• gloves • space blanket• shears • pen and paper• gauze wipes (or similar) • chamois or towel• spare battery (if applicable to AED)

Defibrillation pads + Pad positioning

Prepare the casualty Expose the casualty’s chest (including removing undergarments) It may be necessary to trim hair if the casualty is very hairy, with scissor/shears in the locations

where pads will be placed in order to have good adhesion to the skin Dry the casualty’s skin if necessary, due to immersion or sweat Remove any metal jewellery and medication patches Ensure that the casualty is not lying on metal grates, in pools of water or on other conductive

material.

Safety PrecautionsA safe working environment must be created before defibrillation occurs. There are three areas of danger directly related to the defibrillation process: Contact – no person or conductive material is to be in direct or indirect contact with the casualty

at the time of defibrillation.

Conduction – there should be no conductive items near the casualty, such as:o water/rain (ensure that you are clear of the incoming tide if in a beach environment)o metal/grateso moisture on the chest (eg vomit, blood or perspiration)

Explosiono Do not defibrillate if there is a chance of explosion due to the presence of gases, fumes or

flammable substances.o Oxygen masks should be moved away during defibrillation and the flow of oxygen

directed away from the chest.

Post-defibrillation casualty careIf the defibrillation has not been successful and when the standard protocol is exhausted:

– Leave the pads on the casualty– Continue CPR until relieved or unable to continue– Care for family and friends of the casualty

If the defibrillation has been successful:– Leave the pads on the casualty– Check for breathing– If they are not breathing, continue CPR– If they are breathing, check for a response– If they are not responding, place them in the lateral position– If they are responding, reassure and make them comfortable