Tumor. A tumor may preserve bile from draining out in the gallbladder as it must. This causes bile buildup that may result in cholecystitis. Veins have blood back to the center after the oxygen is removed. In the event the vein is blocked, blood backs up while in the intestines, https://www.sgvascularctr.com/treatments-for-gangrene-insights-from-a-vascular-surgeon/