Airway: suction to prevent aspiration, provide oxygen as needed
Breathing: maintain patient in position of comfort
Circulation: monitor for early signs of shock and provide fluid resuscitation if hypotensive. Blood products should be individualized based on local protocols
Antiemetics can be given to decrease nausea and vomiting
Assume the patient is hepatitis positive and wear appropriate personal protective gear
Undifferentiated upper gastrointestinal bleeding
Peptic ulcer disease 
Lower gastrointestinal bleeding
Gastritis/esophagitis
Acute gastric dilatation
Gastric/esophageal varices
Splenic infarction
Mallory-Weiss tear