I am working in the field of Head and Neck cancer. I see laryngectomy patients and , as with this type of surgery the vagus nerve is severed bilaterally, and there might also be a partial pharyngectomy involved. In any case the pharynx is reconstructed so that now the food passage and airway are separated from each other. The patient now breathes through a hole in the neck. I understand the vagus nerve supplies the oesophagus, but I do not understand what it does. What I do know is that most of my laryngectomy patients suffer from moderate to severe backflow as well as reflux. I would like to know if the surgery impacts on the efficiency of the cardiac sphincter (Lower oesophageal sphincter)