Final answer:
In case of a home mechanical ventilator malfunction, the patient should be disconnected from the device and manually ventilated with a bag-valve-mask while seeking professional assistance.
Step-by-step explanation:
If a patient's home mechanical ventilator malfunctions, the immediate response should be to remove the patient from the ventilator. After disconnecting the patient, commence manual respiration using a bag-valve-mask (BVM) device. The bag-valve-mask allows for manual ventilation of the patient, ensuring they continue receiving oxygen until the ventilator can be repaired or replaced, or until emergency medical services arrive. It is crucial to call for professional help while administering manual ventilation to address the equipment failure and to ensure the patient receives the necessary care.