What is the best way to relieve severe choking in a responsive adult?

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.

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