Anatomy 3.
A Practical Guide to Clinical MedicineA comprehensive physical examination and clinical education site for medical students and other health care professionals |
Content and Photographs by Charlie Goldberg, M.D., UCSD School of Medicine and VA Medical Center, San Diego, California 92093-0611.
Send Comments to: Charlie Goldberg, M.D.
Exam of the Abdomen
Anatomy | Observation | Auscultation | Percussion | Palpation | Findings Associated with Advanced Liver Disease |
The major components of the abdominal exam include: observation, auscultation, percussion, and palpation. While these are the same elements which make up the pulmonary and cardiac exams, they are performed here in a slightly different order (i.e. auscultation before percussion) and carry different degrees of importance. Pelvic, genital, and rectal exams, all part of the abdominal evaluation, are discussed elsewhere.
Think Anatomically: When looking, listening, feeling and percussing imagine what organs live in the area that you are examining. The abdomen is roughly divided into four quadrants: right upper, right lower, left upper and left lower. By thinking in anatomic terms, you will remind yourself of what resides in a particular quadrant and therefore what might be identifiable during both normal and pathologic states.
By convention, the abdominal exam is performed with the provider standing on the patient's right side.
Observation: Much information can be gathered from simply watching the patient and looking at the abdomen. This requires complete exposure of the region in question, which is accomplished as follows:
- Ask the patient to lie on a level examination table that is at a comfortable height for both of you. At this point, the patient should be dressed in a gown and, if they wish, underwear.
- Take a spare bed sheet and drape it over their lower body such that it just covers the upper edge of their underwear (or so that it crosses the top of the pubic region if they are completely undressed). This will allow you to fully expose the abdomen while at the same time permitting the patient to remain somewhat covered. The gown can then be withdrawn so that the area extending from just below the breasts to the pelvic brim is entirely uncovered, remembering that the superior margin of the abdomen extends beneath the rib cage.
Draping the Abdomen - The patient's hands should remain at their sides with their heads resting on a pillow. If the head is flexed, the abdominal musculature becomes tensed and the examination made more difficult. Allowing the patient to bend their knees so that the soles of their feet rest on the table will also relax the abdomen.
- Keep the room as warm as possible and make sure that the lighting is adequate. By paying attention to these seemingly small details, you create an environment that gives you the best possible chance of performing an accurate examination. This is particularly important early in your careers, when your skills are relatively unrefined. However, it will also stand you in good stead when examining obese, anxious, distressed or otherwise challenging patients.
- Appearance of the abdomen. Is it flat? Distended? If enlarged, does this appear symmetric or are there distinct protrusions, perhaps linked to underlying organomegaly? The contours of the abdomen can be best appreciated by standing at the foot of the table and looking up towards the patient's head. Global abdominal enlargement is usually caused by air, fluid, or fat. It is frequently impossible to distinguish between these entities on the basis of observation alone (see below for helpful maneuvers). Areas which become more pronounced when the patient valsalvas are often associated with ventral hernias. These are points of weakening in the abdominal wall, frequently due to previous surgery, through which omentum/intestines/peritoneal fluid can pass when intra-abdominal pressure is increased.
Various Causes of Abdominal Distension
Obese abdomen
Hepatomegaly
Ascites
Markedly enlarged gall bladder
(labeled "GB")
Umbilical Hernia
Same umbilical hernia while patient performs valsalva maneuver. - Presence of surgical scars or other skin abnormalities.
- Patient's movement (or lack thereof). Those with peritonitis (e.g. appendicitis) prefer to lie very still as any motion causes further peritoneal irritation and pain. Contrary to this, patients with kidney stones will frequently writhe on the examination table, unable to find a comfortable position.
What exactly are you listening for and what is its significance? Three things should be noted:
- Are bowel sounds present?
- If present, are they frequent or sparse (i.e. quantity)?
- What is the nature of the sounds (i.e. quality)?
After you have finished noting bowel sounds, use the diaphragm of your stethoscope to check for renal artery bruits, a high pitched sound (analogous to a murmur) caused by turbulent blood flow through a vessel narrowed by atherosclerosis. The place to listen is a few cm above the umbilicus, along the lateral edge of either rectus muscles. Most providers will not routinely check for bruits. However, in the right clinical setting (e.g. a patient with some combination of renal insufficiency, difficult to control hypertension and known vascular disease), the presence of a bruit would lend supporting evidence for the existence of renal artery stenosis. When listening for bruits, you will need to press down quite firmly as the renal arteries are retroperitoneal structures. Atherosclerosis distal to the aorta (i.e. at the take off of the Iliac Arteries) can also generate bruits. Blood flow through the aorta itself does not generate any appreciable sound. Thus, auscultation over this structure is not a good screening test for the presence of aneurysmal dilatation.
Percussion: The technique for percussion is the same as that used for the lung exam. First, remember to rub your hands together and warm them up before placing them on the patient. Then, place your left hand firmly against the abdominal wall such that only your middle finger is resting on the skin. Strike the distal interphalangeal joint of your left middle finger 2 or 3 times with the tip of your right middle finger, using the previously described floppy wrist action (see under lung exam). There are two basic sounds which can be elicited:
- Tympanitic (drum-like) sounds produced by percussing over air filled structures.
- Dull sounds that occur when a solid structure (e.g. liver) or fluid (e.g. ascites) lies beneath the region being examined.
*Special note should be made if percussion produces pain, which may occur if there is underlying inflammation, as in peritonitis. This would certainly be supported by other historical and exam findings.
What can you really expect to hear when percussing the normal abdomen? The two solid organs which are percussable in the normal patient are the liver and spleen. In most cases, the liver will be entirely covered by the ribs. Occasionally, an edge may protrude a centimeter or two below the costal margin. The spleen is smaller and is entirely protected by the ribs. To determine the size of the liver, proceed as follows:
- Start just below the right breast in a line with the middle of the clavicle, a point that you are reasonably certain is over the lungs. Percussion in this area should produce a relatively resonant note.
- Move your hand down a few centimeters and repeat. After doing this several times, you will be over the liver, which will produce a duller sounding tone.
- Continue your march downward until the sound changes once again. This may occur while you are still over the ribs or perhaps just as you pass over the costal margin. At this point, you will have reached the inferior margin of the liver. The total span of the normal liver is quite variable, depending on the size of the patient (between 6 and 12 cm). Don't get discouraged if you have a hard time picking up the different sounds as the changes can be quite subtle, particularly if there is a lot of subcutaneous fat.
- The resonant tone produced by percussion over the anterior chest wall will be somewhat less drum like then that generated over the intestines. While they are both caused by tapping over air filled structures, the ribs and pectoralis muscle tend to dampen the sound.
- Speed percussion, as described in the pulmonary section, may also be useful. Orient your left hand so that the fingers are pointing towards the patients head. Percuss as you move the hand at a slow and steady rate from the region of the right chest, down over the liver and towards the pelvis. This maneuver helps to accentuate different percussion notes, perhaps making the identification of the liver's borders a bit more obvious.
Percussion can be quite helpful in determining the cause of abdominal distention, particularly in distinguishing between fluid (a.k.a. ascites) and gas. Of the techniques used to detect ascites, assessment for shifting dullness is perhaps the most reliable and reproducible. This method depends on the fact that air filled intestines will float on top of any fluid that is present. Proceed as follows:
- With the patient supine, begin percussion at the level of the umbilicus and proceed down laterally. In the presence of ascites, you will reach a point where the sound changes from tympanitic to dull. This is the intestine-fluid interface and should be roughly equidistant from the umbillicus on the right and left sides as the fluid layers out in a gravity-dependent fashion, distributing evenly across the posterior aspect of the abdomen. It should also cause a symmetric bulging of the patient's flanks.
- Mark this point on both the right and left sides of the abdomen and then have the patient roll into a lateral decubitus position (i.e. onto either their right or left sides).
- Repeat percussion, beginning at the top of the patient's now up-turned side and moving down towards the umbilicus. If there is ascites, fluid will flow to the most dependent portion of the abdomen. The place at which sound changes from tympanitic to dull will therefore have shifted upwards (towards the umbillicus) and be above the line which you drew previously. Speed percussion (described above) may also be used to identify the location of the air-fluid interface. If the distention is not caused by fluid (e.g. secondary to obesity or gas alone), no shifting will be identifiable.
The models below should help to clarify the concept of shifting dullness. With the "patient" lying flat on their back balloons (representing the intestines)
float on the water (representing ascites). When the "patient" turns on their right side, a new air fluid level is established.Shifting Dullness (real patient)
Palpation: First warm your hands by rubbing them together before placing them on the patient. The pads and tips (the most sensitive areas) of the index, middle, and ring fingers are the examining surfaces used to locate the edges of the liver and spleen as well as the deeper structures. You may use either your right hand alone or both hands, with the left resting on top of the right. Apply slow, steady pressure, avoiding any rapid/sharp movements that are likely to startle the patient or cause discomfort. Examine each quadrant separately, imagining what structures lie beneath your hands and what you might expect to feel.
- Start in the right upper quadrant, 10 centimeters below the rib margin in the mid-clavicular line. This should insure that you are below the liver edge. In general, it is easier to detect abnormal if you start in an area that you're sure is normal. Gently push down (posterior) and towards the patient's head with your hand oriented roughly parallel to the rectus muscle, allowing the greatest number of fingers to be involved in the exam as you try to feel the edge of the liver. Advance your hands a few cm cephelad and repeat until ultimately you are at the bottom margin of the ribs. Initial palpation is done lightly.
Abdominal Palpation - Following this, repeat the examination of the same region but push a bit more firmly so that you are interrogating the deeper aspects of the right upper quadrant, particularly if the patient has a lot of subcutaneous fat. Pushing up and in while the patient takes a deep breath may make it easier to feel the liver edge as the downward movement of the diaphragm will bring the liver towards your hand. The tip of the xyphoid process, the bony structure at the bottom end of the sternum, may be directed outward or inward and can be mistaken for an abdominal mass. You should be able to distinguish it by noting its location relative to the rib cage (i.e. in the mid-line where the right and left sides meet).
Rib Cage - You can also try to "hook" the edge of the liver with your fingers. To utilize this technique, flex the tips of the fingers of your right hand (claw-like). Then push down in the right upper quadrant and pull upwards (towards the patient's head) as you try to rake-up on the edge of the liver. This is a nice way of confirming the presence of a palpable liver edge felt during conventional examination.
Hooking Edge of the Liver - Place your right hand at the inferior and lateral border of the ribs, pushing down as you push up from behind with your left hand. If the right kidney is massively enlarged, you may be able to feel it between your hands.
- Now examine the left upper quadrant. The normal spleen in not palpable. When enlarged, it tends to grow towards the pelvis and the umbilicus (i.e. both down and across). Begin palpating near the belly button and move slowly towards the ribs. Examine superficially and then more deeply. Then start 8-10 cm below the rib margin and move upwards. In this way, you will be able to feel enlargement in either direction. You can use your left hand to push in from the patient's left flank, directing an enlarged spleen towards your right hand. If the spleen is very big, you may even be able to "bounce" it back and forth between your hands. Splenomegaly is probably more difficult to appreciate then hepatomegaly. The liver is bordered by the diaphragm and can't move away from an examining hand. The spleen, on the other hand, is not so definitively bordered and thus has a tendency to float away from you as you palpate. So, examine in a slow, gentle fashion. The edge, when palpable, is soft, rounded, and rather superficial. Repeat the exam with the patient turned onto their right side, which will drop the spleen down towards your examining hand.
- Exploration for the left kidney is performed in the same fashion as described for the right. Kidney pain, most commonly associated with infection, can be elicited on direct examination if the entire structure becomes palpable as a result of associated edema. This is generally not the case. However, as the kidney lies in the retroperitoneum, pounding gently with the bottom of your fist on the costo-vertebral angle (i.e. where the bottom-most ribs articulate with the vertebral column) will cause pain if the underlying kidney is inflamed. Known as costo-vertebral angle tenderness (CVAT), it should be pursued when the patient's history is suggestive of a kidney infection (e.g. fever, back pain and urinary tract symptoms).
Posterior View: Location of the Kidneys
Gross Retroperitoneum Anatomy - Examine the left and right lower quadrants, palpating first superficially and then deeper. A stool filled sigmoid colon or cecum are the most commonly identified structures on the left and right side respectively. The smooth dome of the bladder may rise above the pelvic brim and become palpable in the mid-line, though it needs to be quite full of urine for this to occur. Other pelvic organs can also occasionally be identified, most commonly the pregnant uterus, which is a firm structure that grows up and towards the umbillicus. The ovaries and fallopian tubes are not identifiable unless pathologically enlarged.
- Finally, try to feel the abdominal aorta. First push down with a single hand in the area just above the umbillicus. If you are able to identify this pulsating structure with one hand, try to estimate its size. To do this, orient your hands so that the thumbs are pointed towards the patient's head. Then push deeply and try to position them so that they are on either side of the blood vessel. Estimate the distance between the palms (it should be no greater then roughly 3 cm). This is, admittedly, a crude technique. Remember also that the aorta is a retorperitoneal structure and can be very hard to appreciate in obese patients. There have been no reports of anyone actually causing the aorta to rupture using this maneuver, so don't be afraid to push vigorously.
Examining for a fluid wave: When observation and/or percussion are suggestive of ascites, palpation can be used as a confirmatory test. Ask the patient or an observer to place their hand so that it is oriented longitudinally over the center of the abdomen. They should press firmly so that the subcutaneous tissue and fat do not jiggle. Place your right hand on the left side of the abdomen and your left hand opposite, so that both are equidistant from the umbillicus. Now, firmly tap on the abdomen with your right hand while your left remains against the abdominal wall. If there is a lot of ascites present, you may be able to feel a fluid wave (generated in the ascites by the tapping maneuver) strike against the abdominal wall under your left hand. This test is quite subjective and it can be difficult to say with assurance whether you have truly felt a wave-like impulse.
The abdominal examination, like all other aspects of the physical, is not done randomly. Every maneuver has a purpose. Think about what you're expecting to see, hear, or feel. Use information that you've gathered during earlier parts of the exam and apply it in a rational fashion to the rest of your evaluation. If, for example, a certain area of the abdomen was tympanitic during percussion, feel the same region and assure yourself that there is nothing solid in this location. Go back and repeat maneuvers to either confirm or refute your suspicions. In the event that a patient presents complaining of pain in any region of the abdomen, have them first localize the affected area, if possible with a single finger, pointing you towards the cause of the problem. Then, examine each of the other abdominal quadrants first before turning your attention to the area in question. This should help to keep the patient as relaxed as possible and limit voluntary and involuntary guarding (i.e. superficial muscle tightening which protects intra-abdominal organs from being poked), allowing you to gather the greatest amount of clinical data. Make sure you glance at the patient's face while examining a suspected tender area. This can be particularly revealing when evaluating otherwise stoic individuals (i.e. even these patients will grimace if the area is painful to the touch). The goal, of course, is to obtain relevant information while generating a minimal amount of discomfort.
Findings Commonly Associated With Advanced Liver Disease: Chronic liver disease usually results from years of inflamation, which ultimately leads to fibrosis and decline in function. Histologically, this is referred to as Cirrhosis. This can be driven by a number of different processes, most commonly chronic alcohol use, viral hepatitis (B or C) or hemachromatosis (the complete list is much longer). It's important to realize that a cirrhotic liver can be markedly enlarged (in which case it may be palpable) or shrunken and fibrotic (non-palpable).
After many years (generally greater then 20) of chronic insult, the liver may become unable to perform some or all of its normal functions. There are several clinical manifestations of this dysfunction. While none are pathonomonic for liver disease, in the right historical context they are very suggestive of underlying pathology. Some of the most common findings are described and/or pictured below.
- Hyperbilirubinemia: The diseased liver may be unable to conjugate or secrete bilirubin appropriately. This can lead to
- Icterus - Yellow discoloration of the sclera.
- Jaundice - Yellow discoloration of the skin.
- Bilirubinuria - Golden-brown coloration of the urine.
- Ascites: Portal vein hypertension results from increased resistance to blood flow through an inflamed and fibrotic liver. This can lead to ascites, accumulation of fluid in the peritoneal cavity.
- Increased Systemic Estrogen Levels: The liver may become unable to process particular hormones, leading to their peripheral conversion into estrogen. High levels promote:
- Breast development (gynecomastia).
- Spider Angiomata - dilated arterioles most often visible on the skin of the upper chest.
- Testicular atrophy.
- Lower Extremity Edema: Impaired synthesis of the protein alburmin leads to lower intravascular oncotic pressure and resultant leakage of fluid into soft tissues. This is particularly evident in the lower extremities.
- Varices: In the setting of portal hypertension, blood "finds" alternative pathways back to the heart that do not pass through the liver. The most common is via the splenic and short gastric veins, which pass through the esophageal venous plexus enroute to the SVC. This causes esophageal varices which can bleed profoundly, though these are not apparent on physical examination. A much less common path utilizes the recanalized umbilical vein, which directs blood through dilated superficial veins in the abdominal wall. These are visible on inspection of the abdomen and are known as Caput Medusae.
Icterus