Chapter 15. Abdominal Pain

See Figure 15–1.

Perform a Brief Examination

First, determine if the patient is stable or not. Distinguishing stability or instability is best performed pragmatically through multiple, simultaneous steps.

1. Look at the patient and identify if the patient is ill appearing.

2. Evaluate responsiveness, focusing on eye opening, and verbal and motor responses.

3. Assess airway, breathing, and circulation.

4. Record and review a complete set of vital signs.

5. Gauge perfusion to the brain and extremities.

6. Continue the physical examination with inspection of the abdomen, looking for signs of an acute abdomen: rebound tenderness, board-like rigidity or guarding, or an obvious pulsatile mass.

7. If appropriate, perform a rectal examination earlier than later, inspecting for blood.

8. In the acute patient, emergency bedside ultrasound is helpful in identifying aortic aneurysm/dissection, intraperitoneal fluid, and/or IVC collapse (volume status).

9. If instability is confirmed, measures to stabilize the patient must be taken immediately.

Caution—A number of patients presenting to the ED with abdominal pain will have a source of that pain outside the abdomen, anatomically, as when epigastric or upper abdominal pain is caused by an acute myocardial infarction, pulmonary embolus, or pneumonia. Occasionally, abdominal pain is due to a metabolic derangement, as is the case with diabetic ketoacidosis. In brief, the differential diagnosis should extend beyond intra-abdominal pathology.

Identify Candidates for Urgent Surgery

Some patients with abdominal pain will require surgical evaluation. Those requiring early surgical evaluation or intervention include patients with an acute abdomen, a pulsatile abdominal mass, or shock with abdominal pain. If hypotension or hemodynamic instability is present with abdominal pain, especially with gastrointestinal bleeding or a rigid abdomen, there is a strong possibility of underlying life-threatening pathology, and surgical consultation should be immediately sought. One of the most critical decisions an ED physician can make is whether a surgeon should be involved or not. Therefore, it is of paramount importance to consider this question early and frequently throughout the evaluation.

Treat Shock

Treat hypotension or frank shock (Chapter 11).

1. Give oxygen at a rate of 2–10 L/min by nasal cannula or mask. Keep oxygen saturation above 95%.

2. Insert two large-bore (≥16-gauge) intravenous catheters in an upper extremity.

3. Obtain blood for a complete blood count (CBC) with differential, serum electrolyte measurements, lipase measurement, renal function tests, liver function tests, serum pregnancy test, serum lactate, and a rapid bedside glucose test. Also, send a tube of blood for typing and crossmatching.

4. Consider emergency bedside ultrasound to evaluate for free intraperitoneal fluid and aortic aneurysm.

5. Immediately begin rapid infusion of crystalloid solution. Titrate rate of infusion to the blood pressure; initially, give a 1-L bolus over 10–20 minutes (adult dose). Remember to exercise caution in ...