In the Surveys -> Engage -> Manage Surveys page, just click the Pause Pulses button to pause the queue Indefinitely or choose to postpone your Pulse Surveys for 1, 2, 3, or 4 weeks. If you have any Flexible Surveys scheduled, they will remain in the queue.
To resume your Pulse Surveys, just click the Resume Pulses, and a pop-up will tell you more about when Pulse Surveys were paused, who paused them, and when your next Pulse Survey will go out if you unpaused your Pulse Surveys today.