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Emergencies & first aid · Essentials

Emergencies & first aid

Twenty-six chapters covering adults and children together. Everything else on this site is about risk over decades; this is about the next four minutes, and about the handful of errors that get made again and again — all of which are settled long before the emergency starts.

All chapters Vital signs, all ages School charts

The short version

  • This topic is the exception on this site. Everything else here is about risk over decades. This is about the next four minutes.
  • The failures it covers are failures of preparation, not of treatment — which is why it belongs on a prevention site. Nobody decides during an emergency to understand what "no shock advised" means.
  • Guidance changed at the end of 2025, and several widely circulated points are now superseded. They are flagged where they appear.
  • Twenty-six chapters plus 5 sub-chapters, all covering adults and children together. Everything here supports a trained responder. It is not training, and it never replaces calling 999.

The five things people get wrong most

  1. Reading "no shock advised" as good news

    An AED shocks only shockable rhythms. A flat, silent heart is not shockable. "No shock advised" cannot distinguish between someone whose heart is beating and someone whose heart has stopped in a way a shock will not fix. If they are unresponsive and not breathing normally, compressions continue.

  2. Standing someone up during anaphylaxis

    The single most counterintuitive instruction in first aid, because helping someone almost always means moving them. In anaphylactic shock it can be fatal within minutes. Lie them flat, raise the legs, and bring help to them.

  3. Trusting a normal oxygen saturation

    It reads falsely high in carbon monoxide poisoning and in people with darker skin, fails entirely in shock, and is frequently normal in early anaphylaxis and sepsis right up until it is not. It also says nothing about whether carbon dioxide is being cleared.

  4. Giving an antihistamine and waiting

    Antihistamines treat the itch. They do nothing for a closing airway or a failing circulation, and the minutes spent waiting for one to work are the minutes that mattered.

  5. Not counting the respiratory rate

    The earliest and most sensitive sign of deterioration in almost every acute illness, the one no monitor does for you, and the one most often left blank.

Two ways in

Every chapter covers adults and children together, with the age differences called out where they exist — because they are usually a paragraph, not a separate subject, and splitting them would mean someone reading the wrong half. These two routes just start you in different places.

Schools and children

Start with vital signs for the age bands, then the school medical room for what to reach for in each situation. Both are laid out to print. Then anaphylaxis and choking, which are the two most likely to arrive without warning in a school.

Home and adults

Start with CPR and defibrillation, then the collapsed or altered person, which covers the four commonest reversible causes — seizure, stroke, hypoglycaemia and opioid overdose. Vital signs has an adult section and a note on why an adult chart cannot work the way a paediatric one does, and pulse oximetry is worth reading before you trust a number off a fingertip device.

All Twenty-six chapters

Vital signs — all ages Children 5–17 and adults, with alert and emergency thresholds and the adult-specific traps. Blood pressure, measured properly Technique for adults and children, cuff sizing, and what a difference between arms can mean. Pulse oximetry Why 94% and 90% are not four points apart, when a perfect reading accompanies serious illness, and the four ways it lies. Single-lead ECG and low-cost monitors What they are good at, the inconclusive rate nobody quotes, and why a reassuring trace during chest pain is dangerous. School medical room Situation-to-equipment tables and a single-lead ECG primer. Cardiac arrest and resuscitation What each actually does, the 2025 changes, and the four ways a pulse oximeter misleads. Choking Infant, child and adult sequences, why thrusts need follow-up, and where shop-bought suction devices belong. Drowning A hypoxic arrest, so the priority inverts — five breaths before compressions. Catastrophic bleeding Pressure, packing, and why a tourniquet is an escalation rather than a last resort. The collapsed or altered person Seizures, stroke beyond FAST, diabetic emergencies, opioid overdose and naloxone. Fainting Three questions separate harmless from dangerous. What to check, how long to keep them down, and the head they banged on the way. Stroke The clock, the drugs and their risks in absolute numbers, what to ask when asked to decide, and preventing the next one. Urinary tract infection Antibiotic choice by group, what survives a penicillin allergy, and why a positive strip in an over-65 means little — with reading a urine dipstick and the interpreter beneath it. Sepsis and meningitis Why waiting for the rash is the commonest way both are missed. Cuts, grazes and cleaning them Tap water as an irrigant, what to do with nothing to hand, and the improvised choices that do harm. Bites and stings Tick removal and what the Lyme rash really looks like, knuckle wounds, and the four things not to do for an adder bite. Head injury Which knocks need hospital, how long to watch, and the subtle signs of a slow bleed weeks later. Burns and scalds Twenty minutes of cool running water matters more than anything done later. Eye and dental injuries Irrigate a chemical splash before finding sterile fluid, and never reimplant a baby tooth. Poisoning and ingestion Paracetamol's silent first day, button batteries as a two-hour emergency, and the four rules covering the rest. Heat illness Hot and lucid is exhaustion; hot and confused is heat stroke. Cool first, transport second. Cold, hypothermia and frostbite Handle gently, warm the trunk not the limbs, and why people deteriorate after rescue. Electrical injury and lightning Power off first, the visible burn is never the injury, and why lightning reverses triage. Crush injury The danger is the release, not the crushing. The fifteen-minute rule and what you can always do. Obstetric emergencies Bleeding, pre-eclampsia, cord prolapse and birth before arrival — with preterm labour protocols and transdermal GTN beneath it. Anaphylaxis Adrenaline by age and weight, and the positioning error that kills.

What this topic is not

  • It is not first aid training. Reading about compressions does not make anyone able to do them under pressure. A half-day course does, and the difference between the two is most of the outcome.
  • It is not a clinical protocol. Verify against current Resuscitation Council UK guidance and your own organisation's policy before relying on any of it.
  • It does not replace 999. Every page here says so, repeatedly, because the failure mode of a reference like this is somebody using it to decide not to call.