How should one respond to a situation where a large choking victim suddenly thrusts?

If a large choking victim suddenly thrusts, step back and allow them to try to dislodge the object themselves. If they are unable to do so, perform the Heimlich maneuver by standing behind them, wrapping your arms around their waist, and delivering upward thrusts to help clear the obstruction. It is important to act quickly and calmly in this situation to prevent further harm.