Lesson Overview
After massive bleeding, the next quick killers are a blocked airway and a failure to breathe. The brain starts to suffer within a few minutes without oxygen, so airway and breathing (the A and R of MARCH, the A and B of ABCDE) follow straight on from bleeding control. This lesson covers opening an airway with basic manual techniques, the recovery position, clearing a choking casualty, recognising when breathing is in trouble, the first-aid management of chest injuries including a chest seal where you are trained and it is issued, and an overview of rescue breathing and CPR. One rule runs through all of it: open the airway before you assess breathing. There is no point checking breathing through a passage that is shut.
This is also the lesson where the limits of buddy aid become sharpest. Some of what a struggling chest needs, such as relieving trapped air with a needle or putting in an artificial airway below the vocal cords, is a medical act performed by a trained clinician with the right kit. It is named here only so you can recognise the emergency and get the casualty to that care fast. At those edges your job is not to perform the act but to keep the airway open, the breathing watched, the help coming, and the casualty moving towards someone who can do more. That care is owed to everyone present by need alone: a casualty is a casualty, treated in the order their injuries demand, whoever they are.
By the end you will be able to recognise a threatened airway, describe head-tilt-chin-lift and jaw thrust at a basic level, explain the purpose and use of the recovery position, clear a blocked airway in a conscious and an unconscious casualty, recognise breathing problems and the basics of chest-injury care, and describe in outline what rescue breathing and CPR are for.
This is the knowledge layer. Opening an airway, the recovery position, the choking drill, applying a chest seal, rescue breathing, and CPR are physical skills that cannot be learned from a screen. They are taught and certified in person, under qualified supervision, and confirmed by practical assessment. You do only what you are trained and currently authorised to do. The clinical detail here follows current accepted first-aid practice and is confirmed by the College's medical staff.
Key Terms
- Airway: the passage carrying air from the mouth and nose to the lungs; in an unconscious casualty it is most often blocked by the tongue falling back.
- Head-tilt-chin-lift: the basic manoeuvre to open the airway by tilting the head back and lifting the chin, used where no neck injury is suspected.
- Jaw thrust: opening the airway by lifting the jaw forward without tilting the head, used where a neck injury is suspected.
- Recovery position: a stable position on the side, used for an unconscious casualty who is breathing, that keeps the airway open and lets fluid drain.
- Choking: a foreign object lodged in the airway of a conscious casualty, partly or wholly blocking the passage of air, treated by back blows and abdominal thrusts.
- Occlusive dressing: an airtight dressing that seals a wound from the outside air; a chest seal is a purpose-made occlusive dressing for a chest wound, and a vented chest seal has a one-way valve that lets trapped air out while letting none in.
- Tension pneumothorax: a build-up of air trapped in the chest that progressively squeezes the lung and then the heart and great vessels; a true emergency whose definitive relief is a medical act, not buddy aid.
- CPR (cardiopulmonary resuscitation): chest compressions, with rescue breaths where trained, for a casualty who is unresponsive and not breathing normally.
Why a blocked airway kills in minutes
Timing sets the order of everything that follows. The body holds only a small reserve of oxygen, a few minutes' worth in the blood and lungs, and the brain spends it fastest of any organ. Once air stops moving, the casualty loses consciousness within a minute or two, and within a handful of minutes brain cells begin to die in a way that does not come back. A blocked airway is not a problem you have time to think about. With massive bleeding, it is one of the two killers that simple hands can defeat in the seconds you have, which is why it sits second in MARCH, straight after the M (Lesson 02).
The same clock fixes the order within A and R. Breathing is air moving through an open passage. If the passage is shut, the chest can heave without a breath of useful air moving, so treating breathing first treats the wrong thing. Open the airway, then ask whether the casualty is breathing through it: in that order, every time.
Recognising and opening the airway
A casualty who is talking, crying, or shouting has, by that very fact, an open airway and a working breath behind it, so your first check is often simply whether they can speak normally. Trouble shows in the sounds and the silence: gurgling (fluid, blood, or vomit), snoring or rasping (the tongue or soft tissue partly blocking the way), a hoarse or changed voice, a high crowing sound on breathing in (stridor, a sign of narrowing high in the airway), or no air movement at all. In an unconscious casualty the commonest cause is the tongue: as the muscles relax, it falls back and closes the throat. The diagram below shows why, and what opening the airway by hand does.
AIRWAY CLOSED (on the back, muscles relaxed) AIRWAY OPEN (head tilted, chin lifted)
nose ___ nose ___
\ \ \ \
) ) mouth ) ) mouth
/__/ /__/
____| |________ ____| |________
| tongue >>> falls back | tongue lifts clear
| ########## <-- blocks throat | ##########
|________________ airway shut |________________ airway open
|| no air can pass || air passes freely
\/ \/
lungs (no air) lungs (air in)
The fastest remedy is to open the airway by hand. Where there is no reason to suspect a neck injury, use the head-tilt-chin-lift. Kneel beside the casualty's head, place the palm of one hand flat on the forehead and press gently so the head tips back, and place the fingertips (not the thumb, and not the soft tissue under the jaw) of your other hand on the bony point of the chin and lift it upward. The tongue, anchored to the jaw, is drawn forward off the back of the throat. You are not forcing the neck; you are tilting it to a "sniffing" angle. Listen and feel for air at once: the snoring or rasping usually stops the moment the passage opens, which tells you it has worked.
Where a neck or spine injury is possible, after a vehicle crash, a fall from a height, a blast, a dive into shallow water, or any heavy blow to the head, do not tilt the head; use the jaw thrust instead. Kneel at the top of the casualty's head, rest the heels of both hands on either side of the head to steady it, hook your fingertips under the angles of the lower jaw (the corners just below the ears), and lift the whole jaw straight upward and forward, sliding the lower teeth ahead of the upper. This pulls the tongue forward and opens the throat while the head and neck stay still and in line. It is more tiring than the head-tilt, the price of protecting a spine you are not sure of. If a jaw thrust alone will not open the airway and the casualty is in real danger of suffocating, a life takes priority over a possible spinal injury: add a careful, minimal head-tilt. An open airway is not optional. The whole decision sits in one question, summarised below.
Need to open the airway
|
v
Any reason to suspect a neck or spine injury?
(fall, crash, blast, dive, blow to the head)
|
+----+--------------------+
| NO | YES (or unsure)
v v
HEAD-TILT-CHIN-LIFT JAW THRUST (no head-tilt)
forehead back, lift angles of jaw forward,
bony chin up keep head and neck in line
|
v
Airway still blocked and
casualty suffocating?
|
v
Add a careful, minimal head-tilt:
a life comes before a possible
spinal injury.
Clearing the airway
Opening the passage does no good if something solid or liquid is sitting in it. With the airway open, look in the mouth: is there blood, vomit, water, food, a broken tooth or dental plate, chewing gum, soil, or any other object? Look before you act, because what you do next depends on what is there.
For fluid, blood, vomit, or water, drain or clear it. The simplest method, where there is no reason to suspect a spinal injury, is to turn the casualty onto their side as a single unit so that gravity carries the fluid out of the mouth; this is the recovery position, below. Where suction is issued and you are trained to use it, suction under direct vision, only as far as you can see, never blindly into the throat.
For a solid object, the rule is short and strict: remove it only if you can plainly see it, and then only with a controlled finger or instrument that hooks it out sideways. Never push a finger blindly into the mouth and throat. A blind finger sweep can push an unseen object deeper, wedge it tighter, or make a casualty bite or vomit. If you cannot see the object, do not hunt for it with a finger; manage the casualty by position and, if they are choking, by the drill below. Looking is encouraged; blind sweeping is not.
The recovery position
An unconscious casualty who is breathing still faces a particular danger: lying on their back, the tongue can fall back and block the airway, and any vomit or blood can run into the lungs. The remedy, where you are trained and there is no reason to suspect a spinal injury, is the recovery position: turn the casualty onto their side, head tilted gently back so the airway stays open and fluid can drain freely from the mouth. This is the protective positioning introduced under the A of MARCH in Lesson 02, set out here in full as a method, and it keeps the airway open without you holding it.
It protects the airway three ways at once. On the side, the tongue falls forward or sideways rather than back, so it no longer shuts the throat. The mouth becomes the lowest point of the face, so blood, vomit, and saliva run out onto the ground instead of down into the lungs. And the body is propped so it cannot roll flat onto the back, where the danger returns, or onto the front, where the chest cannot move freely. A casualty left on their back can be killed by their own tongue or vomit while breathing perfectly well; the recovery position removes both threats and asks nothing of you to maintain.
A workable sequence, as you will be taught and assessed in person, runs like this. Kneel beside the casualty and straighten their legs. Place the arm nearer you out at a right angle, elbow bent, palm up. Bring the far arm across the chest and hold the back of that hand against the casualty's near cheek. With your other hand, grasp the far thigh and pull the far knee up so the foot stays flat on the ground. Using that raised knee as a lever and steadying the hand at the cheek, roll the casualty towards you onto their side. Adjust the upper leg so both hip and knee are bent at right angles, which stops them rolling further. Finally, tilt the head gently back to keep the airway open, and check breathing.
Recovery position (casualty on their side, facing you)
head tilted back, mouth DOWN -> fluid drains out
\
(o_ checks to confirm:
/| - breathing
hand under | chest - airway open
cheek ------+--/ - mouth lowest point
/| / - cannot roll onto back or front
upper / |/
leg _/ | bent hip and knee at right angles
( | prop the body and stop it rolling
\___|
foot flat on the ground
A few points matter. A casualty who is, or may be, pregnant is best placed on their left side, which keeps the weight of the womb off the large blood vessels. Keep checking the breathing every minute or so, because an unconscious casualty can stop breathing at any time; if they do, move at once to the resuscitation steps below. After about half an hour, turn the casualty onto the other side, again as a unit, to spare the lower arm. And the position is for a casualty who is breathing: one who is not breathing normally needs resuscitation on their back, not the recovery position.
Where a spinal injury is suspected the calculation changes, and it is a genuine judgement, not a rule. If skilled help will arrive soon and you are alone, it is often better to hold the airway open by hand (jaw thrust, or a careful head-tilt-chin-lift) and keep the casualty still rather than turn them. If help is some way off, or there are two of you, the casualty can be turned onto their side while the head, neck, and spine are kept in line, which needs more than one pair of hands so the whole body rolls as a single rigid unit. The deciding question is always which threat is the greater now: a casualty drowning in their own vomit must be turned, spine or no spine, because a protected spine is no use to a casualty who has suffocated. Whatever the position, keep checking the breathing.
Choking: clearing a blocked airway in a conscious casualty
Choking is a foreign object, often food, lodged in the airway of someone who was fine a moment ago. It is a different problem from the unconscious casualty whose tongue has fallen back, and it has its own drill. The first task is to recognise it and judge how bad it is, because mild and severe choking are handled differently.
Ask the casualty, "Are you choking?" A casualty with a mild obstruction can still move some air: they can cough, perhaps speak or make a croaky sound, and the cough is forceful. Here their own cough beats anything you can apply, so encourage them to cough, stay with them, do nothing that might interfere, and watch in case it worsens. A casualty with a severe obstruction cannot shift the air: they cannot speak, the cough is silent or absent, the breathing is a high-pitched wheeze or nothing at all, they may clutch the throat (the universal sign of choking), and they will quickly become distressed, then blue, then unconscious. Severe choking needs your hands now.
For the conscious casualty with severe choking, the drill alternates two techniques, summarised in the figure below. First, back blows, up to five. Stand to the side and slightly behind the casualty, support their chest with one hand and lean them well forward so that anything dislodged falls out of the mouth rather than back down the airway, and with the heel of your other hand give up to five sharp blows between the shoulder blades, checking after each; stop as soon as it clears, you do not always give all five. If five back blows fail, switch to abdominal thrusts, up to five. Stand behind the casualty, put both arms around the upper abdomen, clench one fist and place it just above the navel and below the breastbone, grasp it with the other hand, and pull sharply inwards and upwards, up to five times, checking after each; the thrust drives the diaphragm up and forces a blast of air out of the lungs to pop the object free. Then return to five back blows, and keep alternating, five and five, checking after every blow and thrust, until the airway clears or the casualty becomes unconscious.
CHOKING
"Are you choking?"
|
+-------------------------------+
| MILD | SEVERE
| (can cough / speak, | (cannot speak, silent or
| forceful cough) | absent cough, clutching throat)
v v
Encourage coughing. Lean casualty well forward.
Stay. Watch for it 5 BACK BLOWS (heel of hand,
getting worse. between shoulder blades),
checking after each.
| not cleared
v
5 ABDOMINAL THRUSTS
(fist above navel, in and up),
checking after each.
| not cleared
v
Repeat 5 and 5, checking after
every blow and thrust.
|
v
Casualty goes UNCONSCIOUS?
|
v
Lower carefully to the ground,
start resuscitation (CPR),
keep help coming.
What changes when the casualty becomes unconscious is a point students get wrong. You do not keep slapping a casualty who has collapsed. Lower them carefully to the ground, make sure help is being called, open the mouth and remove the object only if you can now plainly see it (no blind sweep), and begin the resuscitation steps below: chest compressions and, where trained, rescue breaths. The compressions do two jobs here, keeping a little blood moving and generating chest pressure that may itself shift the obstruction. After any choking episode that needed thrusts, the casualty should be seen by medical staff, because abdominal thrusts can cause internal injury and an object may have been partly inhaled.
Recognising breathing problems
With the airway open, turn to the breathing itself, using look-listen-feel. Put your cheek close to the mouth and nose for up to ten seconds: look along the chest for it rising and falling, listen for breath sounds, and feel for air on your cheek, all at once. This is the same check you use to confirm breathing in any unresponsive casualty. Judge the rate and depth: breathing that is very fast or very slow, very shallow, or obviously laboured is a danger sign. As a rough guide, a calm adult breathes around twelve to twenty times a minute; much faster, much slower, or barely at all tells you the casualty is in trouble.
Look for the effort of struggling to breathe, the use of neck and shoulder muscles, drawing-in between or below the ribs, flaring nostrils, and a blue or grey tinge to the lips and fingertips, a late and serious sign of a lack of oxygen. Listen for the wheeze of narrowed airways or the bubbling of fluid. Check that both sides of the chest move together; one side that moves poorly, or a casualty whose distress is worsening, points to a problem inside the chest. The danger signs, in one place, are: a rate very fast or very slow; breathing shallow or gasping; obvious hard work to breathe, with neck and rib muscles dragging; noisy breathing (wheeze, gurgle, or stridor); blue or grey lips and fingertips; one side of the chest not moving with the other; and, above all, breathing getting steadily worse. Any of these means the casualty needs more help than first aid can give, and needs it soon.
A conscious casualty struggling to breathe will usually settle into the position they can breathe in best, often sitting up and leaning slightly forward; let them, unless they need to lie flat for another reason, and watch closely. Beware the casualty who has worked hard to breathe and then suddenly looks calmer and sleepier: they may not be improving but tiring towards collapse. Keep watching, keep help coming, and be ready to support the airway and breathing if they go under.
Rescue breaths and the link to resuscitation
If a casualty is unresponsive and not breathing normally, their heart may have stopped: this is cardiac arrest, and it is the reason rescue breathing and CPR exist. Two warnings about recognising it. First, in the early minutes a casualty in arrest may take occasional gasping, irregular breaths; this is not normal breathing, and you treat it as arrest. Second, do not waste time hunting for a pulse you are unsure of; if the casualty is unresponsive and not breathing normally, act.
CPR keeps a trickle of oxygenated blood moving to the brain and heart until skilled help and a defibrillator arrive. In outline, and as you will be taught and assessed in person: call for help and a defibrillator at once; give chest compressions, pushing down firmly on the centre of the chest, hard and fast, at about one hundred to one hundred and twenty a minute and a depth of around five centimetres in an adult (not deeper than about six), letting the chest come all the way back up between compressions; and, where you are trained and willing, combine compressions with rescue breaths, the widely taught pattern being thirty compressions to two breaths.
Rescue breaths are within the scope of a trained first-responder, and they connect directly to the airway work of this lesson, because a rescue breath can only reach the lungs through an open airway. The method, taught and certified in person, is to keep the airway open with head-tilt-chin-lift, pinch the soft part of the nose closed, take a normal breath, seal your lips around the casualty's mouth (or use the pocket mask or face shield issued for the purpose, which protects both of you), and blow steadily for about a second, just enough to see the chest begin to rise, then let it fall before the second breath. If the chest does not rise, reposition the airway and check the mouth for an obstruction before trying again, and do not interrupt compressions for more than the two breaths.
Compression-only CPR, pushing without breaths, is worthwhile and better than nothing if you are untrained in or unwilling to give breaths. The deeper management of circulation and shock, the C that comes after A and R, is the subject of Lesson 05. Even after a casualty is revived, keep watching closely, because they may stop breathing again, and keep help coming until it arrives.
An overview of rescue breathing and CPR
A casualty in cardiac arrest needs four things to fall into place quickly: the arrest recognised and help called; CPR started early and kept going; a defibrillator brought and used as soon as it arrives; and advanced care taking over. The first-responder owns the first two links and helps the third. None of these is a paragraph you can absorb and then perform; each is a drill timed and corrected by an instructor with their hands on yours, which is why this is an overview and the certification is in person. The gap between knowing what to do and being able to do it is widest where the act is physical, fast, and unforgiving. Treat everything in this lesson as the briefing before the drill, not the drill itself.
Chest injuries
Any wound to the chest, or to the back above the waist, deserves particular care, because the chest holds the lungs and the work of breathing. As always, massive bleeding is controlled first. Beyond that, a penetrating chest wound carries a special risk: air can be drawn in through the wound or leak from an injured lung and build up inside the chest, squeezing the lung and, if it goes far enough, the heart. You may see or hear such a wound bubble or hiss as the casualty breathes, air pulled in and out through the hole in the chest wall, which is why it is often called a "sucking" chest wound.
Handling an open chest wound is a point where careful training matters, because the guidance is specific and the techniques differ by what you have been taught and issued. At the most basic level, control any bleeding with pressure that does not completely and permanently seal the wound, sit the casualty in the position they breathe most easily (usually leaning towards the injured side), and get them to advanced care urgently. Where you are trained and a chest seal is issued, it is applied over the wound to stop air being sucked in: expose the wound, wipe the skin around it dry so the dressing will stick, and apply the seal over the hole at the end of a breath out. A vented chest seal has a one-way valve and is the preferred type, because it lets trapped air escape while letting none be drawn in, so pressure cannot build up behind it; place its valve directly over the wound. An unvented, fully occlusive seal closes the hole completely; it stops air being sucked in but can also trap air inside, so it must be watched even more closely. Check the back and sides for an exit wound, and seal that too if you find one and have a second seal.
Whichever method you use, watch the casualty closely afterwards, because a sealed chest wound can turn into the most dangerous chest emergency of all.
When breathing keeps getting worse: tension pneumothorax
If, after the wound is sealed, the casualty's breathing gets steadily worse rather than better, suspect that air is building up inside the chest under pressure: a tension pneumothorax. This is air trapped around a lung that cannot get out, so with every breath more is added and the pressure climbs, first collapsing the lung on that side, then squeezing the heart and great vessels until the circulation begins to fail. It is a true emergency that can develop in minutes. The picture is a casualty, usually with a chest injury, whose breathlessness and distress are worsening, who is breathing ever faster and harder, whose lips and fingertips are turning blue or grey, and whose chest may be unequal, with one side moving poorly; late on, the neck veins may stand out as the casualty slides towards collapse. In short: a chest casualty getting worse, not better, may be developing a tension, and that demands urgent evacuation.
The first aid you can give is bounded. If you applied an unvented seal, lift one edge, or "burp" it, at the end of a breath out to let the built-up air hiss free, then lay it back down, and repeat if the casualty improves and then worsens again. A vented seal should be doing this on its own, but check that its valve is not blocked by blood or a fold in the dressing. Sit the casualty up if breathing is easier that way, keep oxygen flowing if it is issued and you are trained to give it, and above all keep the casualty moving towards advanced care without delay, because the definitive treatment is not something you carry.
That definitive treatment, needle decompression, putting a needle through the chest wall to release the trapped air, is a medical act, not buddy aid. It carries real risk, it is performed by a clinician trained and currently authorised to do it with the right equipment, and it is certified in person; it is named here so you understand what the casualty needs and why speed matters, not so you attempt it. The same line is drawn around putting in an artificial airway below the vocal cords, a surgical airway: that too is a medical act beyond the first-responder's scope, named only so you can recognise the emergency and keep the casualty moving towards the clinician who can perform it. The exact chest-seal technique your unit uses is set and confirmed by the College's medical staff; apply it as taught, and do not improvise.
In Practice: Airway First, Then Breathing at a Roadside Collision
A small RKA team is first on the scene of a collision on a quiet rural road, helping the civil services who are some way off. Two people are hurt, and the team owes care to both by need alone, treating each in the order their injuries demand.
The first casualty, thrown from a vehicle, is unconscious, breathing but snoring loudly, with no obvious heavy bleeding. The crash makes a spinal injury more than possible, so the responder does not tilt the head; they use a jaw thrust, lifting the angles of the jaw forward while a second pair of hands steadies the head and neck. The snoring stops as the tongue lifts clear, the proof the airway has opened. There is a little blood in the mouth, which they can see, so they hold the airway and stand ready to turn the casualty as a single unit if it pools, spine kept in line, because a protected spine is no use to a casualty drowned in their own blood. Help is minutes away, so they hold the airway and keep checking the breathing.
The second casualty has a penetrating chest wound that bubbles and hisses with each breath. Massive bleeding is controlled first; then a trained buddy wipes the skin and applies a vented chest seal at the end of a breath out, valve over the hole, and finds and seals a smaller exit wound on the back. The casualty is sat leaning towards the injured side. A few minutes on, the responder sees the breathing worsening, faster and harder, lips greying: a tension may be developing. They keep the casualty moving towards the arriving medical team without delay, knowing the needle that would relieve it is a medical act they do not perform, and that their job is to keep the airway open, the breathing watched, and the help coming. Neither casualty needed CPR, because both were breathing. The work was to keep the airway open and the breathing watched, in the right order, for both, and to move them quickly to those who could do more.
Check Your Understanding
- Why must the airway be opened before you assess breathing? Describe head-tilt-chin-lift and jaw thrust, and say when you would choose each.
- A conscious casualty is choking and cannot speak or cough. Describe the drill of back blows and abdominal thrusts step by step, and say exactly what changes if they become unconscious. Why is a blind finger sweep forbidden?
- A casualty with a sealed penetrating chest wound is getting steadily more breathless and distressed. What do you suspect, what first aid can you give, and why is the definitive treatment named in this lesson as a medical act rather than something you perform?
Reflection (write a short paragraph): Several techniques in this lesson, opening an airway, the recovery position, the choking drill, a chest seal, rescue breaths, CPR, are described here but learned only under supervision, and one, relieving a tension pneumothorax, is named as a medical act you do not perform at all. Why do you think the College draws those lines so firmly, and how should it shape the way you treat the knowledge in this lesson before your practical training, and the way you behave at a real casualty whose needs run past the edge of what you are trained to do?
Summary
- A blocked airway and a failure to breathe kill within minutes, because the body's oxygen reserve is small and the brain spends it fastest; airway and breathing follow straight after bleeding control, and the airway is opened before breathing is assessed.
- Open the airway by hand: head-tilt-chin-lift (forehead back, bony chin up) where no neck injury is suspected, jaw thrust (angles of the jaw lifted forward, head still) where it is; look in the mouth and remove only a visible obstruction, never with a blind finger sweep.
- Place an unconscious, breathing casualty in the recovery position to keep the airway open and let fluid drain, which protects the airway by bringing the tongue forward and the mouth lowest; adjust for pregnancy and for suspected spinal injury, and keep checking the breathing.
- Treat severe choking in a conscious casualty with up to five back blows alternating with up to five abdominal thrusts, checking after each; if they become unconscious, lower them, start CPR, and remove the object only if now visible.
- Recognise breathing problems by rate, depth, effort, sounds, colour, and unequal chest movement, and watch for steady worsening; control bleeding from chest wounds first, sit the casualty up, and apply a vented chest seal only where trained.
- A sealed chest wound that keeps worsening may be a tension pneumothorax, a true emergency: burp or lift an unvented seal, keep help coming, and evacuate urgently. Needle decompression and a surgical airway are medical acts, beyond buddy aid, certified in person.
- CPR (compressions, with rescue breaths where trained) is for a casualty who is unresponsive and not breathing normally; treat gasping as arrest, give care to everyone by need alone, and learn and certify these skills in person.
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