The abdominal examination can be not only diagnostic to help rule pathology in or out, for example, the cause of the patient's pain, but it can be therapeutic as in a reduction of an umbilical or ventral wall abdominal hernia.
The function of the abdominal examination is two-fold. In the asymptomatic patient during a routine examination, the identification of an abnormality such as a bruit heard over the aorta or hepatomegaly can lead the examiner to make an early diagnosis of a potentially catastrophic illness.
The abdominal examination traditionally is done from the patient's right.
Four Examination Components
Percuss while listening for (1) tympany over air filled structures such as stomach, or (2) dullness to percussion as in mass, hepatomegaly. Look for a splenic enlargement by percussing in Castell's point (the most inferior interspace on the left anterior axillary line) as the patient takes a deep inspiration. Percussion that changes from tympanitic to dull as the patient takes a deep breath suggests splenomegaly with an 82% sensitivity and an 83% specificity. Splenomegaly occurs in trauma, with hematoma, portal hypertension, hematologic malignancies, infection such as HIV and from Ebstein-Barr virus, and splenic infarct.
Percuss for the size of the liver from tympany of the lung to dullness of the liver down to tympany of the bowel below the liver. Search for shifting dullness by percussing from midline to flank to find the limit of tympany and then from having the patient roll on their side and repeating exam to find shifting dullness such as in ascites or free fluid.
Light palpation and then deep palpation. Note to press slowly. Pressing too fast may trap a gas pocket within the intestinal lumen and distend the wall causing a false positive pain. Feel for softness, firmness, guarding, tenderness and rebound. Attempt to find the point of maximal tenderness.
Guarding: progresses from voluntary guarding, in which the patient voluntarily tightens the abdominal muscles to protect a deeper inflamed structure, to involuntary guarding where the intra-abdominal pathology has progressed to cause rigidity of the abdominal muscles that the patient can not relax.
Epigastrium: Palpate for any tenderness such as gastritis or early acute cholecystitis from visceral nerve irritation, defects such as a muscle diastasis, or pulsatile mass from AAA. Use a two-handed technique for estimating aorta size. Place one hand longitudinally on the left along the long axis of the aorta at the lateral border of pulsation. Place the other hand longitudinally on the right side of the abdomen and move it toward the first hand until you fell the border of pulsation.
Liver: Place your palpating hand below the lower rib margin and have the patient exhale and then take in a deep breath. With mild pressure, you should feel the liver margin move under your hand as a gentle wave. Feel for any nodularity or tenderness.
Gallbladder: Gently place the palpating hand below the right lower rib margin at the midclavicular line and ask the patient to exhale as much as possible. As the patient exhales, slowly push your hand deeper. Then ask the patient to inhale deeply. A positive Murphy sign is the sudden cessation of inspiration with pain.
Right Kidney: Use a two-handed technique with the patient supine. Use one hand on the patient's back pushing the kidney forward with the other hand palpating down below the lower rib margin between the mid-clavicular line and the anterior axillary line, looking for enlargement or tenderness.
Spleen: If percussion was positive for splenomegaly or equivocal, place your palpating hand below the left lower rib margin and have the patient exhale and then take a deep breath in. With mild pressure, you should feel the spleen move under your hand as a firm mass. If you suspect a very enlarged spleen, start palpation in the right lower quadrant and work toward the splenic flexure.
Left kidney: Standing on the right side, use a two-handed technique with the patient lying in a right lateral decubitus position. Use one hand on the patient's back pushing the kidney toward you while the other hand is palpating down below the lower rib margin between the mid-clavicular line and the anterior axillary line as the patient takes a deep breath looking for enlargement or tenderness. Alternatively, walk to the patient's left side and palpate the left kidney as the right kidney.
Umbilicus: Palpate the periumbilical area and place the finger in the umbilicus to feel for any defect, mass or an umbilical hernia. Have a patient cough or bear down to feel for any protruding mass.
Left lower quadrant: Palpate for tenderness or mass such as colon mass or tumor, constipation, left ovarian cyst, or ectopic pregnancy.
Right lower quadrant: Palpate over McBurney's point which is located two-thirds down an imaginary line from the umbilicus to the anterior superior iliac spine. Tenderness implies possible appendicitis, inflammation of the ileocolic area such as Crohn disease or infectious etiology with bacteria that have a predilection for the ileocecal area such as Bacillus cereus and Yersinia enterocolitica.
Other helpful signs and maneuvers to identify possible appendicitis are:
Suprapubic area: Palpate for mass such as a fibroid, gravid uterus, or uterine cancer in the female or bladder mass or distension.
Back: With the patient sitting up, perform percussion at the right and left costal-vertebral angle first to determine if there is any renal tenderness as in pyelonephritis.
Inguinal area: Since testicular torsion can radiate to the abdomen and present as abdominal pain, and since a hernia is the second most common cause of abdominal pain from small bowel obstruction, an examination of the genitalia is mandatory. For torsion, look for Bell Clapper deformity or a horizontal line of the testis with tenderness. For an inguinal hernia, place your gloved finger into the inguinal canal and ask the patient to bear down or cough to feel a pulsation on the tip of your finger.
The abdominal examination ends with the rectal examination. Feel for rectal tone and saddle anesthesia looking for neurologic pathology. Gradually placed your lubricated, gloved finger against the back rectal sphincter muscle to dilate the sphincter and slowly slide your finger into the rectum feeling for hemorrhoids, fissures, or foreign bodies. Feel the prostate for size and firmness. Tenderness or bogginess suggest prostatitis. Nodules may suggest cancer. Remove your finger and inspect it for signs of active bleeding or melena. Perform a Guaiac test if bleeding is suspected.
The ultrasound examination is becoming a useful tool to assist in the identification of abdominal pathology.
Abdominal wall muscle and skin pain must be in the differential of abdominal pain.
Abdominal Apoplexy which is sudden onset of bleeding into the abdominal rectus muscle described as a constant severe aching pain well localized to the central abdomen along the rectus sheath. It must be entertained as a potential diagnosis in this day and age of increased use of antiplatelet and anticoagulation medication.
Enthesitis of the tip of the 11th rib can cause gradually worsening aching pain of the upper flank with radiation along the external oblique abdominal muscle to the lower abdomen. Although the External oblique is also attached to the 4 lower ribs the 9th and 10th ribs are supported by attachment to the sternum. The 11th rib is free floating and vulnerable to repetitive movement. Each movement in itself does not do damage, but the sum total of the repetitive movements causes micro-tears in the muscle fibers that are attached to the rib. This is the same mechanism that occurs in tennis players who are twisting their racket arm to put extra spin on the tennis ball and cause an enthesitis of the lateral elbow epicondyle or Tennis Elbow. Movement makes the pain worse
The Garnett sign can be helpful to raise suspicion for a muscular etiology. The Garnett sign consists of laying the examiner's hand gently on the abdominal muscle and having the patient do either an abdominal crunch exercise for the muscles of the upper abdomen where the patient raises both shoulders off the examining table. For lower abdominal muscles the patient is asked to raise their lower legs off the examining table. Increased pain as the muscle under the examiner's hand tightens may signify a muscular component or cause of the pain. If the pain lessens as the muscle tightens up and protects and guards the deeper structures of the abdomen may suggest an intra-abdominal source of pain. The pitfall of this test is that severe intra-abdominal processes such as a perforated appendicitis can cause peritonitis with involuntary guarding and abdominal wall muscle contraction and pain.
Before the appearance of the papules, vesicles, and pustules of Herpes zoster, the neuropathic pain from nerve inflammation will make the flank and abdomen of that dermatome painful and also must be in the differential for abdominal pain. Caution the patient to return or follow up with his primary medical doctor if he sees a rash.
The final pitfall is not utilizing the two most important tools in our toolbox: the tincture of time. Repeated abdominal examinations at one or two-hour intervals to evaluate the evolution of the pain help us to decide if the pain is worsening and needs further work-up or decreasing and the patient is able to be discharged. Another important tool is anticipatory guidance. Inform the patient that all tests now are normal, but life is like a movie, and our examination only shows one frame of that movie. If the pain worsens or other symptoms appear, the patient should return to be reexamined. We want the movie to have a happy ending.
Finally, when faced with a patient with abdominal pain and when all of our technical toys such as CT scan, MRI, and Ultrasound are not helpful, remember the words of Sir Arthur Conan Doyal through his protagonist Sherlock Holmes who said that when you have excluded all the probable causes, whatever is left, no matter how improbable it is, most likely is the cause.
In a time of increased technology with CT scans, ultrasounds, and MRIs, it is easy for the clinician to become a technician and rely solely on technology. It is an excellent clinician who develops the hypotheses for the cause of the patient's symptoms. These are based on the chief complaint, the patient's history, and a physical examination such as the abdominal examination. It is the intelligent clinician who then judiciously orders the appropriate test to knowingly search for specific findings that will either support the hypothesis or force the clinician to reconsider new theories for the cause of the patient's symptoms.
All healthcare workers should know how to perform an exam. The abdominal exam can quickly provide information on any underlying abdominal pathology ranging from an umbilical hernia to an abdominal aortic aneurysm. The abdominal exam must be part of a routine history and physical during admission. If a patient has an abdominal pathology, the abdominal exam can be done serially. Not performing a proper abdominal exam can have serious consequences for a patient, especially those who have an acute abdomen.