Mesothelioma Fluid Buildup

My brother had surgery 12 days ago where they removed a large tumor about 5 pounds and 4 liters of fluid. Before they removed the tumor we didn't know what type of cancer he had. We now know he has Peritoneal Mesothelioma. The fluid continues to build up and he is having difficulty breathing as well as his heart racing. Does anyone know of any conventional or alternative treatments that will help reduce the fluid?