Ileus: This condition, characterized by a temporary halt of the normal contractions of the bowel muscles, is a common post-surgical complication. The symptoms of dysphagia and vomiting can be attributed to the ileus, especially if the surgery was abdominal. The timing of 3 days post-surgery also fits within the typical timeframe for the development of ileus.

Gastroesophageal Reflux Disease (GERD): Post-surgical patients, especially those who have undergone abdominal or thoracic surgery, may experience exacerbation of GERD symptoms, including dysphagia and vomiting, due to increased abdominal pressure or altered gastrointestinal motility.
Postoperative Nausea and Vomiting (PONV): A common complication following surgery, PONV can be triggered by anesthesia, pain, or the surgical procedure itself. While it typically presents earlier, it can persist and contribute to dysphagia due to discomfort or fear of vomiting.
Surgical Site Infection or Abscess: Although less common, an infection at the surgical site can cause systemic symptoms including nausea and vomiting. Dysphagia could be related if the infection involves the esophagus or surrounding structures.

Pulmonary Aspiration: This is a potentially life-threatening condition that can occur post-surgery, especially if the patient has been vomiting. Aspiration of gastric contents into the lungs can lead to severe pneumonia or acute respiratory distress syndrome (ARDS).
Esophageal Perforation: A rare but critical complication, especially if the surgery involved the esophagus or nearby structures. Symptoms can include severe chest pain, vomiting, and dysphagia.
Mesenteric Ischemia: Although rare, this condition involves insufficient blood flow to the intestines and can be a complication of surgery, particularly in elderly patients or those with cardiovascular disease. It presents with severe abdominal pain out of proportion to physical findings, and vomiting.

Acute Esophagitis: Inflammation of the esophagus can be caused by various factors, including infection, drugs, or chemical injury. It's less common post-surgery but could be considered if other causes are ruled out.
Esophageal Stricture: A narrowing of the esophagus that can cause dysphagia. While it's more of a chronic condition, an acute presentation could be considered in the context of recent surgery, especially if there was esophageal manipulation or injury during the procedure.