NG tube helps alleviate the pressure of peristalsis stalled which is what causes the bloating during blockage. yes while vomiting is a clear danger sign that your body is finding its own resolution to the stalled peristalsis it can sometimes pop the blockage free. that's happened to me too. so I guess to amend my comment if you begin to vomit but get no relief ie don't start pooping, then its for sure time to get thee to the ER. because in my unmedically trained opinion your body's next step is to perforate in an attempt to solve the peristalsis stall.