First Aid: How To Do CPR On An Adult

Cardiac arrest occurs when a person's heart stops and they stop breathing. Without a constant supply of oxygenated blood, body cells will die quickly and the brain starts to die within 4 to 6 minutes. There are a number of possible causes including trauma, stroke, angina, heart attack, etc. However, no matter what caused the cardiac arrest, the initial treatment is CPR (Cardio-Pulmonary Resuscitation). This article will explain how to do CPR on an adult. For the purposes of this article, an adult is defined as anyone over the onset of puberty (around 12-14).

NB: This article is based on the 2010 guidelines for CPR from the American Heart Association. For a video from the AHA showing this method, click here. If you are interested in learning more about CPR, you can buy the official book from the American Heart Association here.

Step 1: Ensure that there is no immediate danger to you or the casualty. If there is, try to remove the danger or carefully move the casualty to a safer place. Then, check that the person is unconscious. Tap their shoulders and ask "Are you O.K." or "Can you hear me?". If there is no response, send someone to call an ambulance, or call one yourself if you are alone.

Step 2: If the person is not already on their back, gently roll them onto their back. Support the head and neck as you do so in case they have a spinal injury. Then open their airway using the head-tilt chin-lift technique. This involves placing your hand closest to their head on their forehead, and applying firm pressure to tilt the head back. At the same time you should put 2 fingers (index and middle fingers) on the bony part of their chin and lifting up their chin. Make sure their mouth is not closed, and so not put your fingers on the soft part of the chin as this could block their airway. If you see anything in their mouth that could prevent them from breathing properly, remove it if possible. Vomit, blood, etc. can be removed by carefully rolling the casualty onto their side and sweeping as much of it out as you can with 2 curved fingers.

Step 3: Check that the casualty is breathing. Kneel down beside them and place your cheek just over their mouth, while looking down towards their chest. Then look for any movement of their chest/abdomen that could indicate breathing, listen to see if you hear them breathing and feel for any breathing on your cheek. Note that occasional, ineffective gasps for aire (called agonal breathing), which often occur in the first few minutes of a cardiac arrest, are NOT considered effective breathing. A person with agonal breathing still needs CPR.

Step 5: Give chest compressions. Place the heel of one hand on the centre of their chest (on the breastbone) between the nipples. Place your other hand on top of the first and interlock your fingers. Then push down on the chest about 1.5 - 2 inches, and then bring your hands back up, allowing the chest to recoil fully. Do this 30 times, at a rate of about 100 per minute (a good guide to how fast to go is to keep to the beat of "Stayin' Alive" by the Bee Gees. Many CPR instructors actually use this song in training sessions).

Step 4: Give 2 rescue breaths. Pinch the casualty's nose with one hand, place your mouth over theirs and make a tight seal. Then breathe slowly into their mouth for 1 second, just enough to make their chest visibly rise. Be careful not to blow too hard or fast.

Step 6: Continue giving cycles of 30 compressions and 2 breaths until:
- A doctor tells you to stop
- Patient care is taken over by someone more qualified than you (e.g. doctor, nurse, paramedic).
- You become physically exhausted and cannot continue.
- The patient starts breathing again or wakes up.

Notes:
- Chest compressions are the most important part of CPR, and there are many courses that now teach "compression-only CPR". If you are unable or unwilling to give rescue breaths after you establish that a person is unconscious and not breathing, it is still far better to just give continuous chest compressions until help arrives than to do nothing. Keep at a rate of 100/minute.
If you are trained in CPR, you can buy masks online that allow you to give rescue breaths without making contact with the patient's mouth.

- If you find you are unable to ventilate the patient (i.e. the chest is not rising when you breathe), do not delay chest compressions as a result. Attempt 2 breaths, but if this does not work immediately start chest compressions.

- After each chest compression, make sure to let the chest recoil fully by lifting your hands back up to release all pressure (although do not actually take your hands off the chest). If you do not do this, the heart will not be able to fill with blood and further compressions will not be as effective.

- There is another method for opening the airway, known as a jaw thrust, to be used in trauma situations. This is done to reduce the risk of moving the person's head if they might have injured their spine. However, unless you have been specifically trained in this the head-tilt-chin-lift technique is still recommended as airway takes priority over spinal immobilization. If you have been trained in the jaw thrust, and find yourself unable to do it correctly after a few attempts, you should also use the head-tilt-chin-lift technique.

- Occasionally, ribs or cartilage break during CPR. if you feel or hear ribs breaking, check your hand position and ensure you are pressing on the right point on the patient's chest. If you are, continue CPR. Ribs occasionally break with proper CPR technique, and this does not necessarily mean that you are doing it wrong or pushing too hard.

- Patients often vomit during CPR, so you should be prepared for this. It can occur as a result of blowing too hard or too fast when giving rescue breaths, so ensure that you blow just enough to make the chest rise over 1 second. if the patient does vomit, roll them onto their side and clear as much of it out as you can with your fingers.

- If there is a defibrillator available and you have been trained to use it, obviously do so. If you have not been trained, it is still recommended that you try as defibrillation is the only cure for cardiac arrest, CPR only helps to buy some time. When you establish that a person is unconscious, if you are sending someone to call for an ambulance you should also send for a defibrillator/AED if there is one nearby.

- As CPR is tiring work, if there is more than one person willing and able to do it you should switch after every 5 cycles of 30 compressions and 2 breaths, which should take approximately 2 minutes. Although you might not feel tired after this amount of time, the quality of your CPR can start to decrease.

- Obviously, this article is not intended as a substitute for formal training. I would encourage everyone to get certified in CPR, and preferrably the use of an AED also. If you are trained, you should obviously follow the protocols you were trained to use if they differ in any way from the steps above.