You can distinguish between complete or partial obstruction of the airway by noting the following features:

In partial obstruction, the person may:

• have difficulty breathing, but may be able to call for help
• have a persistent cough (the body's attempt at removing the obstruction)
• produce snoring and/or wheezing sounds.

In complete obstruction, the person may:

• be unable to speak, breathe or cry out
• be gripping his/her throat
• be agitated and distressed
• have a blue/dark tinge on the lips due to low oxygen levels
• rapidly lose consciousness.