The abdominal exam is a key competency for many health care providers. It can provide important information about pathology in organs such as the stomach, bowels, liver, spleen, kidneys, and gallbladder.
Look for the presence of pallor (mucosal surfaces) or jaundice (scleral icterus and skin colour). Observe the contour and symmetry of the abdomen, looking for flank or local bulge. Note any scars, striae, dilated veins, or rashes. Look for signs of liver dysfunction (see examples below).
Frequently, the normal aortic pulsation is visible.
Listen to the abdomen before percussing or palpating, as these can change the frequency of sounds. Normal sounds, such as clicks and gurgles, are normally heard 5-34 times/minute. Bowel sounds which are high pitched and tinkling can represent bowel obstruction. The absence of bowel sounds is when no bowel sounds are heard after auscultating each quadrant for 1 minute.
Bruits can be sometimes be heard in the epigastrium and upper quadrants due to renal artery stenosis. A bruit during both systole and diastole suggests renal stenosis is the cause of hypertension. Bruits can also be heard over the aorta, the iliac arteries, and the femoral arteries, but can frequently be benign in these regions. Bruits can be heard over the spleen representing splenomegaly. Bruits can also be heard over the liver which can be caused by many conditions. It is often difficult to assess what structure the bruit is coming from and should be taken into context with the rest of the abdominal exam.
Percussion helps assess the amount and distribution of gas and stool, liver and spleen size (described below), as well as ascites, and masses.
Gentle palpation is useful for helping relax the patient and identify areas of tenderness, muscular resistance, and some superficial masses. Deep palpation can be used to find abdominal masses. Observe the patient's face while examining to assess for pain. If the patient is frightened or ticklish, start with their hand under yours. Rebound tenderness begins with slow, moderately deep pressure and a quick withdrawal. Pain suggests peritoneal inflammation and can be felt at areas other than that of palpation. Peritonitis findings include localized guarding (muscle contraction with palpation) and rebound tenderness.
Due to its location under the rib cage, the liver can be difficult to assess. The following video demonstrates the use of percussion and palpation to assess the size of the liver.
Always start in the right lower quadrant and percuss towards the right upper quadrant. When assessing liver span, percuss in the rib space for shift from resonance to dullness. Normal liver spans are 6-12 cm in the midclavicular line and 4-8 cm in the midsternal line. While it is the most accurate method, percussion can often underestimate liver size.
Ask the patient to take a deep breath in and palpate towards to right upper quadrant to feel the liver edge as it descends into the abdomen. On inspiration, the liver edge is palpable about 3 cm below the right costal margin midclavicularly. Try to trace the liver edge across its span.
Signs of liver disease can be found across the body. In the hands, clubbing, leuchonychia (white areas of nails), kolionychia (scooped nails), Dupuytren's contracture, thenar muscle wasting and palmar erythema can all suggest liver disease. Asteryxis can be tested if there is concern about hepatic encephalopathy by having the patient extend the arms in front of them, fully flexing the wrist (to have palms pointing outwards) and then closing their eyes. A positive test occurs if the patient's hands 'flap' after a few seconds. Asteryxis is demonstrated in this YouTube video. Spider nevi (telangiectasia) and gynecomastia (breast tissue) in a man can suggest liver disease. Dilated abdominal veins, ascites and caput medusae can represent portal hypertension.
An enlarged spleen usually points anteriorly, downward, and medially.
Percussion raises suspicion of splenomegaly but must be confirmed with palpation. Dullness in Traube's space, above the left midaxillary costal margin, suggests an enlarged spleen, and can occur on inspiration. Traube's space is a crescent-shaped space, encompassed by the lower edge of the left lung, the anterior border of the spleen, the left costal margin and the inferior margin of the left lobe of the liver. Thus, its surface markings are respectively the left sixth rib, the left anterior axillary line, and the left costal margin. Castell's sign is with the patient lying supine. Percuss the area of the lowest intercostal space in the left anterior axillary line (Castell's point) during full inspiration then expiration. If the note changes from resonant on full expiration to dull on full inspiration, the sign is regarded as positive (Grover et al, 1993).
Start palpating for the spleen in the right lower quadrant working up to the left upper quadrant. Ask the patient to take a deep breath in while palpating to feel the spleen edge. The spleen must be grossly enlarged to palpate. The spleen can be palpated with two hands.
A large belly with bulging flanks suggests ascites. This can be distinguished from obesity which usually causes the abdomen to protrude forward. Bulging flanks is a sensitive, but not very specific sign. Fluid-filled flanks will be dull on percussion. There are several physical exam maneuvres for ascites described below.
This test uses percussion for air resonance. Starting at the umbilicus, percuss laterally and make a mark where the resonance becomes dull. Then, have the person roll onto the side where the mark was made and percuss again, noting potential change in fluid level. This test is not very sensitive, but is specific.
The test is only positive with large volumes of ascites. Have the patient or an assistant put the side of their hand down on the patient's midline. Then, tap one side and feel for a fluid wave across the abdomen. This test is sensitive but not specific.
Normal sized kidneys cannot be palpated on exam. Enlarged kidneys can be palpated using two hands, one posteriorly and the other anteriorly. Attempt to "blot" the kidney between your two hands.
abdominal exam video (St George's University Clinical Skills Online)