Approach to upper abdominal pain: Clinical sciences

Abdominal pain is a symptom of many conditions, which can range from mild to serious ones that require surgical intervention. Based on the affected region of the abdomen, abdominal pain can be classified into a right upper quadrant, epigastric, left upper quadrant, periumbilical, right lower quadrant, and left lower quadrant pain.

The first step in evaluating a patient with abdominal pain is to assess their ABCDE to determine if they are stable or unstable. If the patient is unstable, start acute management before doing any diagnostic workup. This means that you might need to stabilize their airway, provide supplemental oxygen, establish IV access, and continuously monitor hemodynamics.

On the other hand, for stable patients, your first step is to obtain a focused history and physical exam, or H&P for short. On history, you should characterize the pain based on its location, severity, and chronicity, and determine aggravating and alleviating factors as well as other associated symptoms. Next, you should quickly assess for any signs of an acute abdomen. In this case, ask for history of recent abdominal or GI procedures such as EGD, colonoscopy, or surgery; as well abdominal aortic aneurysm.

On physical exam, acute abdomen presents with signs of diffuse peritoneal inflammation, including diffuse tenderness, rebound pain, rigidity, and guarding. Also, upright chest x-ray or abdominal x-ray series should be done to check for free air under the diaphragm, which suggests perforation of the viscera.

Now, acute abdomen is also known as a surgical abdomen, since emergency surgical intervention is required for most causes, such as perforated viscus, abdominal sepsis, or ruptured abdominal aortic aneurysm. In this case, exploratory laparotomy is considered both diagnostic and therapeutic, so call for an emergent surgical consult while you continue resuscitation and the diagnostic workup.

Now, once you have ruled out an acute abdomen, the next step is to assess for other causes of upper abdominal pain. The location of pain on history and physical examination can be your best initial guide to narrow your differential diagnoses based on your clinical suspicion.

First, let's start with right upper quadrant pain, which is associated with biliary and liver conditions.