General Appearance, Facies, and Body Habitus

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Chapter 1 General Appearance, Facies, and Body Habitus

Salvatore Mangione, MD

“I knew you came from Afghanistan. From long habit, the train of thought ran so swiftly through my mind that I arrived at the conclusion without being conscious of immediate steps. There were such steps, however. The train of reasoning ran: ‘Here is a gentleman of a medical type, but with the air of a military man. Clearly, an army doctor then. He has just come from the tropics, for his face is dark, and that is not the natural tint of his skin, for his wrists are fair. He has undergone hardship and sickness, as his haggard face says clearly. His left arm has been injured. He holds it in a stiff and unnatural manner. Where in the tropics could an English army doctor have seen much hardship and got his arm wounded? Clearly in Afghanistan.’ The whole train of thought did not occupy a second. I then remarked that you came from Afghanistan and you were astonished.”

Arthur Conan Doyle, A Study in Scarlet, 1887

“You can observe a lot by watching.”

General Appearance

1 What is the value of carefully examining the patient’s general appearance?

It is the Sherlockian value of making a diagnosis at first sight, sometimes while walking down a street. Attentive and knowledgeable observation is a time-honored skill of poets, physicians, and serial killers, beautifully articulated by Sir Arthur Conan Doyle (himself a doctor and a former student of the charismatic bedside diagnostician, Prof. Joseph Bell) in describing the first encounter between Holmes and Watson. The Sherlockian process requires practice and knowledge and is quite challenging. But it is also the most valuable, rewarding, and fun aspect of bedside diagnosis. It is best learned by having the luck to work with a physician who is skilled at it.

A. Posture

3 What information can be obtained from observing the patient’s posture?

In abdominal pain the posture is often so typical as to localize the disease:

Patients with pancreatitis usually lie in the fetal position: on one side, with knees and legs bent over.

Patients with peritonitis are very still and avoid any movement that might worsen the pain.

Patients with intestinal obstruction are instead quite restless.

Patients with renal or perirenal abscesses bend toward the side of the lesion.

Patients who lie supine, with one knee flexed and the hip externally rotated, are said to have the “psoas sign.” This reflects either a local abnormality around the iliopsoas muscle (such as an inflamed appendix, diverticulum, or terminal ileum from Crohn’s disease) or inflammation of the muscle itself. In the olden days, the latter was due to a tuberculous abscess, originating in the spine and spreading down along the muscle. Such processes were referred to as “cold abscesses” because they had neither warmth nor other signs of inflammation. Now, the most common cause of a “psoas sign” is intramuscular bleeding from anticoagulation.

Patients with meningitis lie like patients with pancreatitis: on the side, with neck extended, thighs flexed at the hips, and legs bent at the knees—juxtaposed like the two bores of a double-barreled rifle.

Patients with a large pleural effusion tend to lie on the affected side to maximize excursions of the unaffected side. This, however, worsens hypoxemia (see Chapter 13, questions 48–51).

Patients with a small pleural effusion lie instead on the unaffected side (because direct pressure would otherwise worsen the pleuritic pain).

Patients with a large pericardial effusion (especially tamponade) sit up in bed and lean forward, in a posture often referred to as “the praying Muslim position.” Neck veins are greatly distended.

Patients with tetralogy of Fallot often assume a squatting position, especially when trying to resolve cyanotic spells—such as after exercise.

4 What is the posture of patients with dyspnea?

An informative alphabet soup of orthopnea, paroxysmal nocturnal dyspnea, platypnea and orthodeoxia, trepopnea, respiratory alternans, and abdominal paradox. These can determine not only the severity of dyspnea, but also its etiology (see Chapter 13, questions 35–51).

B. State of Hydration

5 What is hypovolemia?

A condition characterized by volume depletion and dehydration:

Volume depletion is a loss in extracellular salt, through either kidneys (diuresis) or the gastrointestinal tract (hemorrhage, vomiting, diarrhea). This causes contraction of the total intravascular pool of plasma, which results in circulatory instability and thus an increase in the serum urea nitrogen-to-creatinine ratio—a valuable biochemical marker for volume depletion.

Dehydration is instead a loss of intracellular water. It eventually causes cellular desiccation and an increase in serum sodium and plasma osmolality, two useful biochemical markers.

Volume depletion occurs with or without dehydration, and dehydration occurs with or without volume depletion.

6 Which is more common—volume depletion or dehydration?

It depends on the patient’s age. For example, in children (especially younger than 5) the most common cause of hypovolemia is volume depletion without dehydration. This is usually due to excessive extrinsic loss of fluids from vomiting, diarrhea, or increased insensible water losses. Intravascular sodium levels are within reference range (isonatremic volume depletion), indicating that the entire plasma pool is contracted, with solutes (mostly sodium) and solvents (mostly water) lost in proportionate amounts. This is because in children younger than 5, significant fluid losses may occur rapidly, since the turnover of fluids and solute can be three times that of adults. In fact, worldwide diarrheal illnesses with subsequent volume depletion account for nearly 4 million deaths per year in infants and children.

7 Is there any reason why these two processes should be kept separated?

The major one is management. Volume depletion is hemodynamically unstable, requiring rapid saline infusion. Dehydration is less dramatic, usually responding to 5% dextrose infusion.

8 What are the goals of physical examination in assessing hypovolemia?

To determine whether hypovolemia is present

To confirm its degree

9 How do you determine the presence of hypovolemia?

Through the “tilt test,” which measures postural changes in heart rate and blood pressure (BP):

1. Ask the patient to lie supine.

2. Wait at least 2 minutes.

3. Measure heart rate and blood pressure in this position.

4. Ask the patient to stand.

5. Wait 1 minute.

6. Measure heart rate and then blood pressure while the patient is standing. Measure rate by counting over 30 seconds and multiplying by two, which is more accurate than counting over 15 seconds and multiplying by four.

10 Why is important to have the patient supine for at least 2 minutes before (s)he stands?

Because 2 minutes in the supine position is necessary to cause maximal leg pooling of blood, and thus maximal drop in cardiac output and maximal increment in heart rate upon restanding. Hence, 2 minutes in the supine position increases the sensitivity of the tilt test.

11 What physiologic changes occur on standing?

Within 1–2 minutes, 7–8 mL/kg of blood (350–600 mL) shifts to the lower body. This decreases intrathoracic volume, stroke volume, and cardiac output while at the same time increasing circulating catecholamines. This, in turn, speeds heart rate and increases systemic vascular resistance. It also shifts blood from the pulmonary to the systemic circulation—all compensatory changes aimed at normalizing blood pressure. When these measures are ineffective (because of autonomic disregulation) or overwhelmed (because of blood loss), orthostatic changes will ensue.

12 Should the patient lie supine for more than 2 minutes before standing up?

No. A longer period does not increase the sensitivity of the test.

13 Is sitting equivalent to standing?

No. In fact, sitting greatly reduces the degree of leg “pooling” and thus the sensitivity of the test.

14 What is the normal response to the tilt test?

Going from supine to standing, a normal patient exhibits the following:

Heart rate increases by 10.9 ± 2 beats/minute and usually stabilizes after 45–60 seconds.

Systolic blood pressure decreases only slightly (by 3.5 ± 2 mmHg) and stabilizes in 1–2 minutes.

Diastolic blood pressure increases by 5.2 ± 2.4 mmHg. This, too, stabilizes within 1–2 minutes.

Hence, you should count the heart rate after 1 minute of standing, and only afterwards measure the blood pressure. This will allow an additional minute for blood pressure to stabilize.

15 Does the tilt test changes with age?

Yes. As patients get older, age-related autonomic dysfunction will cause the postural increase in heart rate to become smaller and the decrease in blood pressure to become larger.

16 What is orthostatic hypotension?

It is a persistent drop in systolic blood pressure >20 mmHg going from supine to a standing position. When not associated with dizziness, this finding has low specificity for hypovolemia; it is encountered with equal frequency in hypovolemic and normovolemic subjects (see later).

17 What is the heart rate response to a tilt test?

It depends on the degree of hypovolemia. Most patients with severe blood loss (600–1200 mL) exhibit clear-cut orthostatic changes, like feeling dizzy upon standing (which practically stops the test) or experiencing a postural increase in heart rate (>30/min). As opposed to an isolated change in blood pressure, these findings are quite specific for hypovolemia, but sensitive only for large blood losses (100%). For moderate losses (<600 mL), their sensitivity is lower (10–50%).

18 So what are the findings of a positive tilt test for hypovolemia?

The most helpful is a postural increase in heart rate of at least 30 beats/minute (which has a sensitivity of 97% and a specificity of 96% for blood loss >630 mL). This change (as well as severe postural dizziness, see later) may last 12–72 hours if IV fluids are not administered.

The second most helpful finding is postural dizziness so severe to stop the test. This has the same sensitivity and specificity as tachycardia. Mild postural dizziness, instead, has no value.

Hypotension of any degree while standing has little value unless associated with dizziness. In fact, an orthostatic drop in systolic BP >20 mmHg unassociated with dizziness can occur in one third of patients >65 years old and 10% of younger subjects, with or without hypovolemia.

Supine hypotension (systolic BP <95 mmHg) and tachycardia (>100/min) may be absent, even in patients with blood losses >1 L. Hence, although quite specific for hypovolemia when present, supine hypotension and tachycardia have low sensitivity; they are present in one tenth of patients with moderate blood loss and in one third with severe blood loss. Paradoxically, blood-loss patients may even present with bradycardia as a result of a vagal reflex.

Note that bedside maneuvers have been primarily studied in patients with blood loss. They have not been as extensively evaluated for hypovolemia from vomiting, diarrhea, or decreased oral intake.

19 What is the significance of an orthostatic drop in systolic blood pressure?

It reflects intravascular depletion, usually from blood loss. Yet, this may also occur in normovolemia. Moreover, it has a sensitivity of only 9% for blood loss of 450–630 mL. Hence, it is not particularly useful—and definitely much less useful than the postural heart rate response.

20 In addition to volume loss, are there any other causes of an abnormal tilt test?

The most common is the inability of the heart to increase its output as a result of pump failure. Postural changes can also be due to cardiac inability to increase rate (a common phenomenon in the elderly), various neurogenic disorders, autonomic neuropathies, certain antihypertensives, prolonged bed rest, and even the weightlessness of space travel.

21 How do you assess skin turgor?

By pinching the abdominal skin with thumb and forefinger, pulling it upward over the abdominal plane, and then suddenly releasing it. Normal skin quickly returns to its original position.

22 What is poor skin turgor?

It is a loss of elasticity, another bedside indicator of hypovolemia. The physiology behind this test is rooted in the extreme changes in elastin caused by a decrease in moisture. Impaired elasticity (which may result from loss of as little as 3.4% in wet weight) prolongs the cutaneous recoil time by 40 times, delaying the skin’s ability to spring back into place, and thus resulting in “tenting”—the lingering of the skin as a crease above the abdominal plane. Since older patients have less elasticity, this test has no real diagnostic value in adults. In children, instead, it is useful. Yet, since skin turgor may reflect not only the level of hydration (including electrolyte status) but also the level of nutrition (i.e., the amount of subcutaneous fat), “tenting” can be absent in cases of obesity or hypernatremic dehydration. Hence, the standard assessment of hypovolemia in all patients remains a set of basic laboratory tests: serum electrolytes, urea nitrogen, and creatinine.

23 What is the capillary refill time?

Another bedside assessment of volume status. This can be carried out through the “nail blanch test.” Place the patient’s hand at the same level as the heart, and then compress the distal phalanx of the middle finger for 5 seconds until it blanches. Release pressure, and measure how long it takes for the nail bed to regain its normal color. At room temperature (21°C), the upper limits of this capillary refill time (CRT) are 2 seconds for children and adult men, 3 seconds for adult women, and 4.5 seconds for the elderly. At colder temperatures, the normal upper limit may even be higher, raising questions regarding the reliability of the test in the prehospital setting.

24 What is the significance of a prolonged CRT?

It suggests tissue hypoperfusion and thus dehydration with possible hypovolemic shock. In adults, a prolonged CRT can also suggest heart failure or peripheral vascular disease.

25 How useful is CRT prolongation in estimating dehydration of infantile diarrhea?

Probably useful. In a study of 32 infants, 2–24 months of age, who had diarrhea, a CRT of <1.5 seconds was found to be indicative of a <50 mL/kg deficit or of a normal infant; 1.5–3.0 seconds suggested a deficit between 50–100 mL/kg, and >3 seconds suggested a deficit of >100 mL/kg. Conversely, in 30 age-matched normal controls, CRT was 0.81–0.31 seconds. Yet, in another study of approximately 5000 children evaluated in an emergency ward, a CRT >3 seconds was a poor predictor of the need for either intravenous fluid bolus or hospital admission.

26 How valuable is CRT in adults?

Not valuable at all. Using the age- and sex-specific upper limits of normal that were previously described, a prolonged CRT does not accurately predict 450 mL of blood loss (6% sensitivity, 93% specificity, positive likelihood ratio [LR], 1.0). Diagnostic performance is not improved by using an arbitrary upper limit of 2 seconds (11% sensitivity, 89% specificity, positive LR, 1.0). Hence, although the test has good interobserver agreement, its clinical value in adults is limited.

27 What other bedside findings can estimate the patient’s volume status?

Dry mucous membranes

Longitudinal tongue furrows

Interobserver agreement for these findings is moderate (80%). In a study of 100 ill elderly patients, dry axillae had a 50% sensitivity for detecting dehydration (percentage of dehydrated subjects without sweating) and a specificity of 82% (percentage of nondehydrated subjects with sweating). They also had a positive predictive value of 45% (percentage without sweating who were dehydrated) and a negative predictive value of 84% (percentage with sweating who were not dehydrated). Using likelihood rations, dry axillae do increase the probability of hypovolemia (positive LR, 2.8), although their sensitivity is rather low (50%). Conversely, moist axillae slightly decrease the probability of volume depletion (negative LR, 0.6).

28 How valuable are dry mucous membranes in adults?

Valuable. In a study of elderly patients admitted to the emergency department, indicators that correlated best with dehydration severity (but were unrelated to patient age) included dry tongue, dry oral mucosae, and longitudinal tongue furrows (all with p <0.001). Other statistically significant indicators are upper body muscle weakness and confusion (p <0.001) and speech difficulty/sunken eyes (p <0.01).

29 What is the significance of dry mucous membranes in children?

It also indicates volume depletion. Still, several other findings may suggest this diagnosis, with their number increasing in proportion to the severity of the condition:

Mild depletion corresponds to <5% intravascular contraction (i.e., <50 mL/kg loss of body weight). This is usually determined by history alone, since physical signs are minimal or absent. Mucosae are moist, skin turgor and capillary refill normal, and pulse slightly increased.

Moderate depletion corresponds instead to 100 mL/kg loss of body weight. Mucosae are dry, skin turgor reduced, pulses weak, and patients are tachycardic and hyperpneic.

Severe depletion corresponds to >100 mL/kg loss of body weight. All previous signs are present, plus cold, dry, and mottled skin; altered sensorium; prolonged refill time; weak central pulses; and, eventually, hypotension.

C. State of Nutrition

30 What information should be obtained about the patient’s state of nutrition?

First, you should determine whether the patient is well nourished or malnourished. Then, whether (s)he is overweight, and, if so, to what degree. Distribution of obesity also should be determined.

31 What is the BMI?

It is the acronym for body mass index, the federal government’s standard for body weight. This represents the proportion of height to weight, expressed as the ratio between a subject’s weight and height (normal range, 18.5–24.9). The BMI provides a much better measurement of body fat than the traditional weight and height charts. For example, currently anyone with a BMI >25 is considered overweight; however, older standards classify men with a BMI >27.3 as overweight and women with a BMI >27.8 as overweight. In fact, those with a BMI of 25.0–29.9 are overweight, and those with a BMI >30.0 are obese. In younger subjects, a BMI >25 is a good predictor of cardiovascular risk. Yet, this may not apply to the elderly (see later).

32 How common is obesity?

Epidemic. Given the revised guidelines, more than half of all Americans age 20 or older are overweight; more than one fifth are obese—a percentage that has dramatically risen since the 1960s.

34 What are the cutoffs for BMI?

In a New England Journal of Medicine study, subjects with a BMI <19 had the lowest death rate. Risk of death was 20% higher if BMI was 19–24.9; 30% higher if 25–26.9; 60% higher if 27–28.9; and twice as high (100%) if >29. This may vary if there are comorbid conditions.

35 What is a comorbid condition?

Any condition associated with obesity that worsens as the degree of obesity increases, and, conversely, improves as obesity is successfully treated. Risk of disease based only on BMI increases whenever the patient has one or more comorbid conditions.

36 How do you measure the BMI?

The best way is a BMI chart, wherein you simply locate the height (inches) and weight (pounds) of a patient and then find the corresponding BMI at the intersection of the two. BMI can also be determined by dividing weight in kilograms by height in meters squared (BMI = kg/m²). The following formula provides a shortcut: (1) multiply weight (in pounds) by 703; (2) multiply height (in inches) by height (in inches); (3) divide the answer in step 1 by the answer in step 2.

37 Is the BMI foolproof?

No. Although a better predictor of disease risk than weight alone, it may be inaccurate in growing children or frail and sedentary elderly patients. It may also be spuriously increased in competitive athletes and body builders (because of larger muscle mass), or pregnant and lactating women. Overall, indices of distribution of body fat have recently gained favor as better risk predictors.

38 How important is the distribution of body fat?

Very important, since it strongly determines the impact of obesity on health. Fat deposition may be central (mostly in the trunk) or peripheral (mostly in the extremities) (Fig. 1-1).

Central obesity has a bihumeral diameter greater than the bitrochanteric diameter; subcutaneous fat has a “descending” distribution, being mostly concentrated in the upper half of the body (neck, cheeks, shoulder, chest, and upper abdomen).

Peripheral obesity has instead a bitrochanteric diameter greater than the bihumeral diameter; subcutaneous fat has an “ascending” distribution, being mostly concentrated in the lower half of the body (lower abdomen, pelvic girdle, buttocks, and thighs).

Figure 1-1 Peripheral (A and B) and central (C) obesity.

Men tend to have central obesity, whereas women have peripheral obesity. Upper and central body fat distribution (especially if intra-abdominal rather than subcutaneous) is a greater predictor of insulin resistance and cardiovascular risk than BMI alone. It also has higher association with hypertension, diabetes, atherosclerotic cardiovascular diseases, and other chronic metabolic conditions (metabolic syndrome). For example, a waist-to-hip ratio ≥1.0 is considered an “at risk” indicator for both men and women, confirming that an apple shape (extra weight around the stomach) is more dangerous than a pear shape (extra weight around hips or thighs). Subjects judged to be lean by BMI alone may be very insulin resistant if their body fat is centrally distributed.

39 How do you assess body fat distribution?

By waist circumference (WC) and waist-to-hip ratio (WHR). Of these, WC is a better predictor of abdominal fat content, and both are much better markers for cardiovascular risk than BMI alone.

40 How do you measure the WC?

By applying a measuring tape between the last rib and the iliac crest, at minimal inspiration and to the nearest 0.1 cm (0.04 in). This coincides with the narrowest waist level, just above the umbilicus.

41 How do you measure the WHR?

As a waist circumference divided by hip circumference. To do so, tape-measure hip circumference at the widest part of the buttocks, and divide this by the previously measured waist circumference. The ratio is the WHR. This may be especially valuable in the elderly, since a recent British study by Fletcher et al. showed that in subjects older than 75 a high WHR (>0.99 in nonsmoking men and >0.90 in nonsmoking women) is associated with a 40% higher risk of cardiovascular disease/death than a lower WHR (≤0.8). The BMI was instead a less important predictor. In fact, older men and women with lower BMI (less than 23 and 22.3, respectively) were actually the ones most likely to die, suggesting that a low BMI in this population may indicate muscle loss or poor nutrition. Hence, in the elderly the WHR is a more accurate indicator of excess body fat.

42 What is the WHR threshold for cardiovascular risk?

The cutoff seems to be a waist-to-hip ratio of 0.83 for women and 0.9 for men. Favoring WHR over BMI would result in a threefold increase in the population at risk for myocardial infarction. This would be especially valuable in Asia, where obesity by BMI is rare, but WHRs can be quite abnormal (Table 1-1).

Table 1-1 Cardiovascular Risk Based on Waist-to-Hip Ratio

43 What is the WC threshold for cardiovascular risk?

It depends on age and sex. Overall, the cutoff for cardiovascular risk is 102 cm (40.2 in) in men and 88 cm (34.7 in) in women. Yet, a WC <100 cm practically excludes insulin resistance in both

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