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General Approach to the Physical Exam

Source: <a href="https://www.jove.com/author/Jaideep+S._Talwalkar">Jaideep S. Talwalkar</a>, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
The examination of the body is fundamental to the practice of medicine. Since the Roman Empire, physicians have described the connection between alterations in function of specific parts of the body and specific disease states and have sought to further scientific understanding to improve bedside diagnosis. However, in this modern age of increasing technology within medical diagnostics, it is important to consider the role that physical examination plays today. It is misguided to believe that physical examination holds all the answers, and much has been written about the questionable utility of certain maneuvers previously held in high regard. It is equally misguided to suggest that physical examination plays little role in the modern patient encounter.
Physical examination remains a valuable diagnostic tool; there are many diagnoses that can only be made by physical examination. A diagnosis made by labs or imaging is rarely done in the absence of findings detectable at the bedside. As the provider conducts a history and physical, they are actively generating and testing hypotheses to explain the patient&#39;s condition. The information one gathers may not replace the need for testing, but having firm hypotheses in place allows the provider to order tests more judiciously and ask better questions of those tests. This, in turn, has the potential to reduce risk to the patient and save cost for the health care system. Finally, physical examination plays a critical role in the therapeutic relationship. By engaging in the time-honored ritual of physical examination, the clinician has the opportunity to develop rapport (by demonstrating attention and sensitivity) and promote healing through the deliberate and responsible use of touch.

Preliminary Diagnosis/Prognosis through Physical Examination

Source: Jaideep S. Talwalkar, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
The examination of the body is fundamental to ...

Observation and Inspection

Source: <a href="https://www.jove.com/author/Jaideep+S._Talwalkar">Jaideep S. Talwalkar</a>, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
Observation and inspection is fundamental to physical examination and begins at the first point of contact with a patient. While observation and inspection are often used interchangeably, observation is a general term that refers to the careful use of one&#39;s senses to gain information. Inspection is an act limited to what one can observe visually, and when referring to physical examination, typically refers to findings on the surface of the body, rather than to behaviors. Skilled clinicians utilize all of their senses to assist with gaining an understanding of their patients, relying on vision, touch (percussion and palpation), and hearing (percussion and auscultation) primarily. Smell can also provide important diagnostic information during the patient encounter (e.g., personal hygiene, substance use, or metabolic diseases). Fortunately the sense of taste is largely a historical relic in medicine, though it is interesting to note that diabetes mellitus was diagnosed for many centuries by the sweet taste of the urine. Through experience, clinicians develop an important sixth sense - the gut instinct - that can only be gained through deliberate practice of clinical skills on thousands of patients over many years. The clinician&#39;s gut instinct, which is based largely on bedside observations, has been shown to be a strong predictor of serious illness. This video and the others in the clinical skills video collection are steps on the way to learning this level of mastery.

Inspection of the Skin, Eyes, Ears, Scalp and Medical History

Source: Jaideep S. Talwalkar, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
Observation and inspection is fundamental to ...

Palpation

Source: <a href="https://www.jove.com/author/Jaideep+S._Talwalkar">Jaideep S. Talwalkar</a>, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
The physical examination requires the use of all of the provider&#39;s senses to gain information about the patient. The sense of touch is utilized to obtain diagnostic information through palpation.
The specific parts of the examiner&#39;s hand used for palpation differ based on the body part being examined. Because of their dense sensory innervation, the finger pads are useful for fine discrimination (e.g., defining the borders of masses, lymph nodes) (Figure 1). The dorsal surface of the hand provides a rough sense of relative temperature (Figure 2). The palmar surfaces of the fingers and hands are most useful for surveying large areas of the body (e.g., abdomen) (Figure 3). Vibration is best appreciated with the ulnar surface of the hands and 5th fingers (e.g., tactile fremitus) (Figure 4).
While palpation is fundamental to the diagnostic aspect of the physical exam, it is also important to acknowledge the role that touch plays in communicating caring and comfort during the patient encounter. Patients generally perceive touch from a healthcare provider in a positive light, and their perceptions of a healthcare provider can be shaped by the skilled use of touch during clinical encounters.1 Physical contact has been associated with alterations in hormonal and neurotransmitter levels, specifically decreases in cortisol and increases in serotonin.2
Therefore, through the careful use of palpation, and touch in general, during the physical examination, the clinician has the opportunity to gain important diagnostic information, while developing rapport and promoting healing.
<img alt="Figure 1" src="/files/ftp_upload/10143/10143fig1.jpg" /> 
Figure 1. Lymph node examination with finger pads. 
<img alt="Figure 2" src="/files/ftp_upload/10143/10143fig2.jpg" /> 
Figure 2. Using the dorsum of hand to assess for warmth.
<img alt="Figure 3" src="/files/ftp_upload/10143/10143fig3.jpg" /> 
Figure 3. Abdominal palpation with palmar surface of fingers and hands. 
<img alt="Figure 4" src="/files/ftp_upload/10143/10143fig4.jpg" /> 
Figure 4. Using the ulnar surface of the hand to assess for tactile fremitus.

Palpation for Lymph Nodes, Abdomen and Tactile Fremitus

Source: Jaideep S. Talwalkar, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
The physical examination requires the use of ...

Percussion

Source: <a href="https://www.jove.com/author/Jaideep+S._Talwalkar">Jaideep S. Talwalkar</a>, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
Simply stated, percussion refers to the striking of one object against another to produce sound. In the early 1700s, an Austrian inn-keeper&#39;s son, named Leopold Auenbrugger, discovered that he could take inventory by tapping his father&#39;s beer barrels with his fingers. Years later, while practicing medicine in Vienna, he applied this technique to his patients and published the first description of the diagnostic utility of percussion in 1761. His findings faded into obscurity until the prominent French physician Jean-Nicolas Corvisart rediscovered his writings in 1808, during an era in which great attention was focused on diagnostic accuracy at the bedside.1
There are three types of percussion. Auenbrugger and Corvisart relied on direct percussion, in which the plexor (i.e. tapping) finger strikes directly against the patient&#39;s body. An indirect method is used more commonly today. In indirect percussion, the plexor finger strikes a pleximeter, which is typically the middle finger of the non-dominant hand placed against the patient&#39;s body. As the examiner&#39;s finger strikes the pleximeter (or directly against the surface of the patient&#39;s body), sound waves are generated. If using indirect percussion, important information is gained from the vibration in the pleximeter finger, as well.2 The third type of percussion, auscultatory percussion, relies on the clinician using a stethoscope to discern differences in sounds created by the plexor finger.
The density of the structure underlying the site of percussion determines the tone of the percussion note; the denser the structure, the quieter the note. Notes differ in relative intensity, pitch, and duration, and help the examiner determine what lies below the skin surface. Knowledge of what particular locations on the body should sound like, in conjunction with the particulars of a specific clinical situation, can help a clinician determine if percussion notes in a particular patient are normal or not.

Clinical Percussion Examination: Direct, Indirect and Auscultatory

Source: Jaideep S. Talwalkar, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
Simply stated, percussion refers to the ...

Auscultation

Source: <a href="https://www.jove.com/author/Jaideep+S._Talwalkar">Jaideep S. Talwalkar</a>, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
Through auscultation, the clinician is able &#34;to eavesdrop on the workings of the body&#34; to gain important diagnostic information.1 Historically, the term &#34;auscultation&#34; was synonymous with &#34;immediate auscultation,&#34; in which the examiner&#39;s ear was placed directly against the patient&#39;s skin. Although this was standard practice for centuries, the method proved inadequate in nineteenth-century France, due to social norms and suboptimal diagnostic yield. This led Ren&#233; La&#235;nnec to invent the first stethoscope in 1816 (Figure 1), a tool that has since become inseparable from auscultation in modern clinical practice, and patients hold it as a symbol of honor and trustworthiness among those who carry them.2
<img alt="Figure 1" src="/files/ftp_upload/10153/10153fig1.jpg" /> 
Figure 1. A representative illustration of the first stethoscope invented by Ren&#233; La&#235;nnec.
The stethoscope has undergone many technologic advances since La&#235;nnec&#39;s initial hollow wooden tube. Practically speaking, the provider must understand the difference between the two sides of the modern stethoscope&#39;s chest piece: the diaphragm and the bell (Figure 2).
<img alt="Figure 2" src="/files/ftp_upload/10153/10153fig2.jpg" /> 
Figure 2. Parts of a modern stethoscope.
When applied firmly against the patient&#39;s skin, the diaphragm transmits high frequency sounds. Sounds from within the patient vibrate the membrane of the diaphragm. These vibrations result in the propagation of sound through the column of air inside the stethoscope and into the examiner&#39;s ears. Conversely, when applied lightly, the bell transmits low frequency sounds. The bell acts as a cup that directly transmits sounds from within the patient through the tubing of the stethoscope. Pressing more firmly with the bell can stretch the underlying skin, essentially turning it into a diaphragm. Auscultation is used in a wide variety of clinical settings. It most commonly plays a role in the examination of the chest, heart, abdomen, and vasculature.

Auscultation and Working Mechanism of a Stethoscope

Source: Jaideep S. Talwalkar, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
Through auscultation, the clinician is able ...

Proper Adjustment of Patient Attire during the Physical Exam

Source: <a href="https://www.jove.com/author/Jaideep+S._Talwalkar">Jaideep S. Talwalkar</a>, MD, and Joseph Donroe, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
In order to optimize the predictive value of the physical examination, the provider must perform maneuvers correctly. The proper use of drapes is an important component of correctly performing physical examination maneuvers. Skin lesions are missed when &#34;inspection&#34; occurs through clothing, crackles are erroneously reported when the lungs are examined through a t-shirt, and subtle findings on the heart exam go undetected when auscultation is performed over clothing. Accordingly, the best practice standards call for examining with one&#39;s hands or equipment in direct contact with the patient&#39;s skin (i.e., do not examine through a gown, drape, or clothing). In addition to its clinical value, the correct draping technique is important for improving the patient&#39;s comfort level during the encounter.
Like all other aspects of the physical exam, it takes deliberate thought and practice to find the right balance between draping, which is done to preserve patient modesty, and exposure, which is necessary to optimize access to the parts that need examination. Individual provider styles in the use of gowns and drapes vary considerably based on the site of practice, resource availability, and discipline within medicine. This video provides a general overview of some of the most common techniques used, combining techniques that utilize common draping approaches.

Patient Attire During Physical Exam; Use of Gowns and Drapes

Source: Jaideep S. Talwalkar, MD, and Joseph Donroe, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
In order to optimize the ...

Blood Pressure Measurement

Source: Meghan Fashjian, ACNP-BC, Beth Israel Deaconess Medical Center, Boston MA
The term blood pressure (BP) describes lateral pressures produced by blood upon the vessel walls. BP is a vital sign obtained routinely in hospital and outpatient settings, and is one of the most common medical assessments performed around the world. It can be determined directly with the intra-arterial catheter or by indirect method, which is a non-invasive, safe, easily reproducible, and thus most used technique. One of the most important applications of BP measurements is the screening, diagnosis, and monitoring of hypertension, a condition that affects almost one third of the U.S. adult population and is one of the leading causes of the cardiovascular disease.
BP can be measured automatically by oscillometry or manually by auscultation utilizing a sphygmomanometer, a device with an inflatable cuff to collapse the artery and a manometer to measure the pressure. Determination of the pulse-obliterating pressure by palpation is done prior to auscultation to give a rough estimate of the target systolic pressure. Next, the examiner places a stethoscope over the brachial artery of the patient, inflates the cuff above the expected systolic pressure, and then auscultates while deflating the cuff and observing the manometer readings. When the pressure in the cuff falls below the pressure in the brachial artery, the turbulent blood flow in a partially squeezed artery produces the Korotkoff audible sounds. The first audible Korotkoff sound signifies the maximum arterial pressure during systole. When the pressure in the cuff is reduced further and falls below the minimal arterial pressure (during diastole), the Korotkoff sounds become no longer audible. The reading at this point signifies the diastolic blood pressure. The blood pressure is measured in mmHg and recorded as a fraction (systolic BP/ diastolic BP).
In most instances, the vital signs are initially measured by a health care assistant or registered nurse (RN). The physician may choose to repeat the vital signs and blood pressure measurement after completion of the patient interview. Repeated measurement of blood pressure is especially important given the potential measurement errors and blood pressure variations.

Blood Pressure Measurement Using a Sphygmomanometer

Source: Meghan Fashjian, ACNP-BC, Beth Israel Deaconess Medical Center, Boston MA
The term blood pressure (BP) describes lateral pressures produced by ...

Measuring Vital Signs

Source: Meghan Fashjian, ACNP-BC, Beth Israel Deaconess Medical Center, Boston MA
The vital signs are objective measurements of a patient&#39;s clinical status. There are five commonly accepted vital signs: blood pressure, heart rate, temperature, respiratory rate, and oxygen saturation. In many practices, pain is considered the sixth vital sign and should regularly be documented in the same location as the other vital signs. However, the pain scale is a subjective measurement and, therefore, has a different value according to each individual patient.
The vital signs assessment includes estimation of heart rate, blood pressure (demonstrated in a separate video), respiratory rate, temperature, oxygen saturation, and the presence and severity of pain. The accepted ranges for vital signs are: heart rate (HR), 50-80 beats per minute (bpm); respiratory rate (RR), 14-20 bpm; oxygen saturation (SaO2), &#62; 92%; and average oral temperature, ~98.6 &#176;F (37 &#176;C) (average rectal and tympanic temperatures are ~1&#176; higher, and axillary temperature is ~1&#176; lower compared to the average oral temperature).
Vital signs serve as the first clue that something may be amiss with a patient, especially if the patient is unable to communicate. Although there are quoted normal ranges, each patient should be considered as an individual and not treated without taking into account the entire clinical picture.

Vital Signs: BP, Heart Rate, Temperature, Respiratory Rate and Oxygen Saturation

Source: Meghan Fashjian, ACNP-BC, Beth Israel Deaconess Medical Center, Boston MA
The vital signs are objective measurements of a patient&#39;s clinical ...

Respiratory Exam I: Inspection and Palpation

Source: <a href="https://www.jove.com/author/Suneel_Dhand">Suneel Dhand</a>, MD, Attending Physician, Internal Medicine, Beth Israel Deaconess Medical Center
Disorders of the respiratory system with a chief complaint of shortness of breath are among the most common reasons for both outpatient and inpatient evaluation. The most obvious visible clue to a respiratory problem will be whether the patient is displaying any signs of respiratory distress, such as fast respiratory rate and/or cyanosis. In a clinical situation, this will always require emergent attention and oxygen therapy.
Unlike pathology in other body systems, many pulmonary disorders, including chronic obstructive pulmonary disease (COPD), asthma, and pneumonia, can be diagnosed by careful clinical examination alone. This starts with a comprehensive inspection and palpation. Keep in mind that in non-emergency situations the patient&#39;s complete history will have been taken already, gaining important insight into exposure histories (e.g., smoking), which could give rise to specific lung diseases. This history can then confirm physical findings as the examination is performed.

Respiratory Exam I: Palpation, Chest and Peripheral Examination

Source: Suneel Dhand, MD, Attending Physician, Internal Medicine, Beth Israel Deaconess Medical Center
Disorders of the respiratory system with a chief ...

Respiratory Exam II: Percussion and Auscultation

Source: <a href="https://www.jove.com/author/Suneel_Dhand">Suneel Dhand</a>, MD, Attending Physician, Internal Medicine, Beth Israel Deaconess Medical Center
Learning the proper technique for percussion and auscultation of the respiratory system is vital and comes with practice on real patients. Percussion is a useful skill that is often skipped during everyday clinical practice, but if performed correctly, it can help the physician to identify underlying lung pathology. Auscultation can provide an almost immediate diagnosis for a number of acute pulmonary conditions, including chronic obstructive pulmonary disease (COPD), asthma, pneumonia, and pneumothorax.
The areas for auscultating the lungs correspond to the lung zones. Each lung lobe can be pictured underneath the chest wall during percussion and auscultation (Figure 1). The right lung has three lobes: the superior, middle, and inferior lobes. The left lung has two lobes: the superior and inferior lobes. The superior lobe of the left lung also has a separate projection known as the lingual.
<img alt="Figure 3" src="/files/ftp_upload/10041/10041fig1.jpg" /> 
Figure 1. Anatomy of lungs with respect to the chest wall. An approximate projection of lungs and their fissures and lobes to the chest wall anteriorly. RUL - right upper lobe; RML - right middle lobe; RLL - right lower lobe; LUL - left upper lobe; LLL - left lower lobe.

Respiratory Exam II: Percussion, Auscultation, Lung Lobes and Breath Sounds

Source: Suneel Dhand, MD, Attending Physician, Internal Medicine, Beth Israel Deaconess Medical Center
Learning the proper technique for percussion and ...

Cardiac Exam I: Inspection and Palpation

Source: <a href="https://www.jove.com/author/Suneel_Dhand">Suneel Dhand</a>, MD, Attending Physician, Internal Medicine, Beth Israel Deaconess Medical Center
The cardiac assessment is one of the core examinations performed by almost every physician whenever encountering a patient. Disorders of the cardiac system are among the most common reasons for hospital admission, with conditions ranging from myocardial infarction to congestive heart failure. Learning a complete and thorough cardiac examination is therefore crucial for any practicing physician.
If there is pathology in the heart or circulatory system, the consequences can also be manifested in other bodily areas, including the lungs, abdomen, and legs. Many physicians instinctively reach straight for their stethoscopes when performing cardiac exams. However, a large amount of information is gained before auscultation by going through the correct sequence of examination, starting with inspection and palpation.

Cardiac Exam I: Palpation, Chest and Peripheral Examination

Source: Suneel Dhand, MD, Attending Physician, Internal Medicine, Beth Israel Deaconess Medical Center
The cardiac assessment is one of the core ...

Cardiac Exam II: Auscultation

Source: <a href="https://www.jove.com/author/Suneel_Dhand">Suneel Dhand</a>, MD, Attending Physician, Internal Medicine, Beth Israel Deaconess Medical Center
Proficiency in the use of a stethoscope to listen to heart sounds and the ability to differentiate between normal and abnormal heart sounds are essential skills for any physician. Correct placement of the stethoscope on the chest corresponds to the sound of cardiac valves closing. The heart has two main sounds: S1 and S2. The first heart sound (S1) occurs as the mitral and tricuspid valves (atrioventricular valves) close after blood enters the ventricles. This represents the start of systole. The second heart sound (S2) occurs when the aortic and pulmonary valves (semilunar valves) close after blood has left the ventricles to enter the systemic and pulmonary circulation systems at the end of systole. Traditionally, the sounds are known as a &#34;lub-dub.&#34;
Auscultation of the heart is performed using both diaphragm and bell parts of the stethoscope chest piece. The diaphragm is most commonly used and is best for high-frequency sounds (such as S1 and S2) and murmurs of mitral regurgitation and aortic stenosis. The diaphragm should be pressed firmly against the chest wall. The bell best transmits low-frequency sounds (such as S3 and S4) and the murmur of mitral stenosis. The bell should be applied with a light pressure.

Cardiac Exam II: Auscultation and Lub-dub Heart Sounds

Source: Suneel Dhand, MD, Attending Physician, Internal Medicine, Beth Israel Deaconess Medical Center
Proficiency in the use of a stethoscope to listen ...

Cardiac Exam III: Abnormal Heart Sounds

Source: <a href="https://www.jove.com/author/Suneel_Dhand">Suneel Dhand</a>, MD, Attending Physician, Internal Medicine, Beth Israel Deaconess Medical Center
Having a fundamental understanding of normal heart sounds is the first step toward distinguishing the normal from the abnormal. Murmurs are sounds that represent turbulent and abnormal blood flow across a heart valve. They are caused either by stenosis (valve area too narrow) or regurgitation (backflow of blood across the valve) and are commonly heard as a &#34;swishing&#34; sound during auscultation. Murmurs are graded from 1 to 6 in intensity (1 being the softest and 6 the loudest) (Figure 1). The most common cardiac murmurs heard are left-sided murmurs of the aortic and mitral valves. Right-sided murmurs of the pulmonary and tricuspid valves are less common. Murmurs are typically heard loudest at the anatomical area that corresponds with the valvular pathology. Frequently, they also radiate to other areas.
<img alt="Figure 1" src="/files/ftp_upload/10135/10135fig1.jpg" /> 
Figure 1. The Levine scale used to grade murmur intensity. 
In addition to the two main heart sounds, S1 and S2, which are normally produced by the closing of heart valves, there are two other abnormal heart sounds, known as S3 and S4. These are also known as gallops, because of the &#34;galloping&#34; nature of more than two sounds in a row. S3 is a low-pitched sound heard in early diastole, caused by blood entering the ventricle. S3 is a sign of advanced heart failure, although it can be normal in some younger patients. S4 is heard in late diastole and represents ventricular filling due to atrial contraction in the presence of a stiff ventricle. S4 is also heard in heart failure and left ventricular hypertrophy.

Cardiac Exam III: Abnormal Heart Sounds and Levine Scale

Source: Suneel Dhand, MD, Attending Physician, Internal Medicine, Beth Israel Deaconess Medical Center
Having a fundamental understanding of normal heart ...

Peripheral Vascular Exam

Source: Joseph Donroe, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
The prevalence of peripheral vascular disease (PVD) increases with age and is a significant cause of morbidity in older patients, and peripheral artery disease (PAD) is associated with cardiovascular and cerebrovascular complications. Diabetes, hyperlipidemia, hypertension, and tobacco use are important disease risk factors. When patients become symptomatic, they frequently complain of limb claudication, defined as a cramp-like muscle pain that worsens with activity and improves with rest. Patients with chronic venous insufficiency (CVI) often present with lower extremity swelling, pain, skin changes, and ulceration.
While the benefits of screening asymptomatic patients for PVD are unclear, physicians should know the proper exam technique when the diagnosis of PVD is being considered. This video reviews the vascular examination of the upper and lower extremities and abdomen. As always, the examiner should use a systematic method of examination, though in practice, the extent of the exam a physician performs depends on their suspicion of underlying PVD. In a patient who has or is suspected to have risk factors for vascular disease, the vascular exam should be thorough, beginning with inspection, followed by palpation, and then auscultation, and it should include special maneuvers, such as determining the ankle brachial index. Maneuvers that make use of a handheld Doppler are demonstrated in a companion video.
<img alt="Figure 1" src="/files/ftp_upload/10122/10122fig1.jpg" /> 
Figure 1. The major arm and leg arteries.

Peripheral Vascular Exam and Major Arm and Leg Arteries

Source: Joseph Donroe, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
The prevalence of peripheral vascular disease (PVD) ...

Peripheral Vascular Exam Using a Continuous Wave Doppler

Source: Joseph Donroe, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
Peripheral vascular disease (PVD) is a common condition affecting older adults and includes disease of the peripheral arteries and veins. While the history and physical exam offer clues to its diagnosis, Doppler ultrasound has become a routine part of the bedside vascular examination. The video titled &#34;The Peripheral Vascular Exam&#34; gave a detailed review of the physical examination of the peripheral arterial and venous systems. This video specifically reviews the bedside assessment of peripheral arterial disease (PAD) and chronic venous insufficiency using a handheld continuous wave Doppler.
The handheld Doppler (HHD) is a simple instrument that utilizes continuous transmission and reception of ultrasound (also referred to as continuous wave Doppler) to detect changes in blood velocity as it courses through a vessel. The Doppler probe contains a transmitting element that emits ultrasound and a receiving element that detects ultrasound waves (Figure 1). The emitted ultrasound is reflected off of moving blood and back to the probe at a frequency directly related to the velocity of blood flow. The reflected signal is detected and transduced to an audible sound with a frequency directly related to that of the received Doppler signal (thus, faster blood flow produces a higher frequency sound).
<img alt="Figure 1" src="/files/ftp_upload/10123/10123fig1.jpg" /> 
Figure 1. Generation of a Doppler signal. The handheld Doppler emits an ultrasound signal, which is then reflected back by moving blood, and finally received by the Doppler probe.
The HHD is easily used in the office or hospital setting to detect pulses, screen for PAD using the ankle brachial pressure index (ABPI), and localize venous insufficiency. This video reviews these procedures; however, it is not intended to be a comprehensive review of non-invasive vascular testing.

Source: Joseph Donroe, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT
Peripheral vascular disease (PVD) is a common ...

Science Education - Clinical Skills

Physical Examinations I