After asking if the person is choking and if they need help: Perform abdominal thrusts. If that doesn't work, lay the victim on their back and perform chest compressions.
I had an elderly woman almost die in my arms today. After chocking on her meal, her breathing was completely obstructed. 3-4 people attempted abdominal thrusts with no success. As she began to lose consciousness, I took over the attempts. I correctly applied the Heimlich Maneuver with all of my strength with no avail.
After she lost consciousness, I lay her down on the floor and a petite 28-year old woman said she wanted to apply chest compressions. The crowd objected saying that was only for heart attacks. The young woman persisted, saying that she had recently learned this technique in a first aid class. Within 30 seconds of chest compressions, bubbles started coming out of the elderly woman's mouth and she slowly started breathing again (still unconscious).
Here's further research that I later found. In a previous case report a standard chest compression successfully removed a foreign body from the airway after the Heimlich manoeuvre had failed. Based on this case, standard chest compressions and Heimlich manoeuvres were performed by emergency physicians on 12 unselected cadavers with a simulated complete airway obstruction in a randomised crossover design. The mean peak airway pressure was significantly lower with abdominal thrusts compared to chest compressions, 26.4±19.8 cmH2O versus 40.8±16.4 cmH2O, respectively (P=0.005, 95% confidence interval for the mean difference 5.3-23.4 cmH2O). Standard chest compressions therefore have the potential of being more effective than the Heimlich manoeuvre for the management of complete airway obstruction by a foreign body in an unconscious patient.
More info at link
Perform abdominal thrust
arm up above head pat on back
If they are coughing, encourage them to keep coughing. DO NOT PAT THEIR BACKS, this may lodge the object further in their throat. If they are no longer coughing, and can not breathe at all, the hiemlec (sp?) maneuver is your best option.
Do not hit them on the back; it will just lodge the food in further and cause more severe choking. Instead do the hemlic remover: have the person stand in front of you, wrap your hands around them and make a fist and cover it with your other hand, then place it on their stomach and push then relax, push then relax, and repeat this until an emergency vehicle arrives.
Perform the 5 back blows, then the 5 abdominal thrusts. Repeat until the object is dislodged or they go unconscious.
choking hazard?
call for help and do the Heimlich remover
Get a big glass of water and drink it all
Back blows and abdominal compressions
Look in the mouth, sweep if you see the object; attempt to ventilate, 30 compressions if breaths don't go in; repeat sweep, breaths, compressions, until breaths go in.
Look for the object; if there is no object in the mouth, attempt the 2 breaths. If breaths don't go in, repeat the sequence of compressions, look for object (sweep then if you see it), attempt the 2 breaths, etc until the breaths go in & you can check for a pulse.
There is not a difference in choking treatment between an adult and a child; 5 back blows and 5 upward abdominal thrusts. Back blows and thrusts would be less force for a child and you may have to adjust your height by going down on 1 or 2 knees.