Which of the following procedures can lead to aspiration?

Bag-mask ventilation can lead to aspiration primarily due to the nature of the procedure itself. During bag-mask ventilation, if the airway is not adequately sealed or if the patient's airway is compromised, there is a risk that stomach contents or foreign materials could enter the airway. This can happen if there is any significant airway obstruction or if the patient struggles or gag reflex is activated during the procedure.

Additionally, the use of high-pressure ventilation can inadvertently force air into the stomach, leading to increased gastric pressure, which increases the likelihood of regurgitation. If the patient has not been properly airway managed and has a full stomach, the risk of aspiration is higher.

Understanding the mechanics of bag-mask ventilation and maintaining proper seal and technique are essential to minimizing this risk during airway management in emergency situations.