The pediatric physical examination: General principles and standard measurements

INTRODUCTION — Sophisticated technologic advances in medicine have proved to be remarkably beneficial in the diagnostic process, yet the well-performed history and the physical examination remain the clinician's most important tools. They are venerated elements of the art of medicine, the best series of diagnostic tests we have [1].

A relatively complete physical examination should be performed on each patient, regardless of the reason for the visit. Numerous medical anecdotes relate instances in which the examination revealed findings unrelated to and unexpected from the patient's chief complaint and major concerns. On occasion, a limited or inadequate examination may miss a significant condition, mass lesion, or potentially life-threatening condition.

The general principles, standard measurements, and overall approach to the pediatric patient are discussed here. Examination of specific organ systems is discussed separately.

●(See "The pediatric physical examination: HEENT".)

●(See "The pediatric physical examination: Chest and abdomen".)

●(See "The pediatric physical examination: Back, extremities, nervous system, skin, and lymph nodes".)

●(See "The pediatric physical examination: The perineum".)

GENERAL PRINCIPLES

The approach — Before entering the room, the clinician should review the patient's record and confirm the identity of the patient and others in the room. This may avoid greeting the patient, parent, or caregiver by the wrong name. The examiner should always knock on the door and await a response before entering by gently opening the door. Small children standing on the other side can be injured easily by the door handle or by the door's impact as it is being opened.

Regardless of whether the clinician and caregiver have met previously, it is appropriate to greet everyone in a cordial manner, maintaining a professional yet friendly demeanor. Clinicians should introduce (or reintroduce) themselves and any colleagues or students observing or participating in the visit and ask those in the room to introduce themselves as well, particularly if the clinician is uncertain of the relationship between the caregiver(s) and the child.

Infants older than six months and anxious toddlers who are leery of strangers often are more comfortable when held by their caregiver. To gain the child's confidence and to avoid an early adversarial relationship, the clinician should try using a calm approach, a reassuring smile, and a toy or bright object as a diversion. An appropriate distance should be maintained during the history-taking portion. The clinician's approach should be cautious and nonthreatening once the physical examination is about to begin.

Infants younger than six months who have no stranger anxiety and children older than 30 to 36 months who are familiar with the examining clinician and/or who possess a trusting demeanor generally cooperate during the examination without being held. Physical examination of 5- to 12-year-old children usually is easy to perform because these children are not typically apprehensive and tend to be cooperative.

General appearance — The examiner may gain significant insight into important social and family dynamics by observation alone when entering the patient's room. Terms used to describe a patient's general appearance include:

●Degree of comfort (calm, nervous, shy)

●State of well-being (normal, ill-appearing, distressed)

●activity level (sedate, alert, active, fidgety)

●Physical appearance (neat, disheveled, unkempt)

●Behavior and attitude (happy, sad, irritable, combative)

●Body habitus (overweight, underweight, short, tall)

●Nutritional status (malnourished, normal, corpulent)

Initial observations may help the clinician form a hypothesis, further supported by physical examination findings. As examples:

●If the child and caregiver make no eye contact or the patient lacks animation and has no social smile, neglect is one possibility. Psychosocial intervention may be warranted. (See "Child neglect: Evaluation and management".)

●If a child appears ill, the clinician should note the patient's preferred position.

•A child who lies completely still on the examination table, is verbally responsive, but noticeably winces when an attempt is made to change position may have an acute abdomen. (See "Emergency evaluation of the child with acute abdominal pain".)

•A dyspneic patient who is sitting upright and slightly forward with the arms extended and hands resting on the knees might be experiencing an exacerbation of asthma or other causes of respiratory distress.

●If an infant is crying, the pitch and intensity of the cry should be noted.

•A boisterous hardy cry is reassuring.

•A weak and listless cry may indicate a seriously ill infant.

•A high-pitched, screeching cry may indicate increased intracranial pressure, reaction to a painful injury, toxic reaction, strangulated inguinal hernia, or other serious disorders.

●Note the patient's breathing pattern. If the patient has rapid, shallow respiration yet appears to be in no acute distress, the underlying cause could be primary pulmonary disease or respiratory compensation for metabolic acidosis. (See "Approach to the child with metabolic acidosis".)

●The examiner should evaluate the developmental status before touching the child, including during history taking. The patient's motor function, interaction with surrounding objects and people, response to sounds, and speech pattern give clues about whether the patient is developing typically or is in need of more comprehensive developmental assessment. (See "Developmental-behavioral surveillance and screening in primary care", section on 'Approach to surveillance'.)

History — Historical information depends almost completely upon the caregiver for patients in the neonatal age range through early childhood. To obtain pertinent information regarding a 5- to 12-year-old child, the clinician must still rely primarily on the caregiver, although comments made by the patient are often relevant.

When appropriate, adolescent patients should have some time with the clinician in the absence of caregivers to permit more open discussion of pertinent historical information, anticipatory guidance, and preventive health care issues. (See "Guidelines for adolescent preventive services" and "Confidentiality in adolescent health care".)

Key elements in the history-taking process include establishing a warm, caring atmosphere and asking questions in a nonconfrontational, unhurried manner. The terminology and language used by the examiner should be appropriate for the health literacy of the caregiver and the patient. Good eye contact and a sense of undivided attention should be maintained. The clinician should sit opposite the caregiver and/or patient at a comfortable distance, unencumbered by large objects, such as desks or tables. Outside interruption by the medical staff and by telephone calls should be kept to a minimum. Before beginning the history, clinicians should explain that they may occasionally need to refer to the electronic or written medical record to review laboratory results, imaging reports, or other pertinent information. An effort should be made to maintain an uninterrupted dialogue, to write few notes, and as much as possible to refrain from turning their back to the patient/caregiver to look at the medical record.

Physical examination — Examiners should wash their hands thoroughly before beginning and after completing the examination. Protective gloves should be worn when appropriate.

Skilled clinicians employ different techniques to gain pediatric patient cooperation. The use of toys, distracting objects, and pictures helps in the examination of young children, infants, and toddlers. Engaging the two- to four-year-old in stories or a discussion of imaginary animals frequently creates an effective diversion. Food, in the form of chewable snacks or liquid refreshments, can be used as a means of pacification, depending upon the stage of the examination.

When an otherwise typically behaving child older than four years fails to cooperate for an examination, even in the presence of a familiar caregiver, it may be an indication of either an earlier traumatic encounter between the patient and another examiner or that the current examining clinician should try a different approach. The possibility of an underlying psychosocial problem or behavior disorder should be considered if a child older than four years is extremely uncooperative or combative.

For patients old enough to understand but who appear apprehensive, the examiner should explain what is going to be done during the examination and allow them to look at and touch any of the instruments to be used. Older patients should be warned in advance of potential pain or discomfort.

The examination of an infant, toddler, or child should be performed in the presence of a parent or guardian; if the parent's or guardian's presence may interfere with the examination (eg, suspected child abuse), a chaperone should be present [2,3]. The use of a chaperone is appropriate for the examination of the anorectal and genital areas and/or breasts of male and female adolescent patients. The clinician should explain the reason for the examination and describe how the examination will proceed. The gender of the chaperone should be determined by the patient’s wishes and comfort (if possible). Ideally, the utilized chaperone should be a staff member rather than a family member. The use and identity of the chaperone should be identified in the medical record.

If the patient has a complaint, sign, or symptom that appears to involve a particular part of the anatomy, that part of the examination should be performed last. As an example, consider a patient complaining of right-lower-quadrant abdominal pain thought to be attributable to appendicitis; by not examining that part of the body first, the clinician may be able to divert the patient's attention away from the involved area and rule out other possible causes for the pain.

Patient privacy should be respected. If a patient objects to being unclothed or to wearing an examination gown, allow them to remain clothed until a specific part of the anatomy must be checked. When an area needs to be examined, the patient should be asked to remove or pull free the garments that are hindering visualization, palpation, or auscultation.

The order in which the physical examination is conducted often is age-specific and depends upon examiner preference. For an infant and younger child, the clinician may prefer to begin by examining the eyes, noting the red-light reflex, extraocular eye muscle movements, and visual tracking and then move to other parts of the body or organ systems before finally performing the often sensitive ear examination. For the older, more cooperative child, the examination might begin at the head and progress down the body, with the neurologic examination performed last. In general, the portions of the pediatric examination that require the most patient cooperation, such as blood pressure measurement, lung and heart auscultation, and eye and neurologic examinations, are performed initially. These examinations are followed by the more bothersome portions, including abdominal and ear examinations and measurement of head circumference.

STANDARD MEASUREMENTS

Growth parameters — Measurement of the standard growth parameters throughout childhood and adolescence is essential for assessing normal development [4]. Data obtained should be plotted on standard growth curves to determine progress.

Weight — Weight is measured at each periodic well-child visit (figure 1A-B and figure 2A-B) (calculator 1). The evaluation of children with abnormal weight or weight trajectory is discussed separately.

●Poor weight gain (see "Poor weight gain in children younger than two years in resource-abundant settings: Etiology and evaluation" and "Poor weight gain in children older than two years in resource-abundant settings", section on 'Diagnostic approach')

●Overweight and obesity (see "Clinical evaluation of the child or adolescent with obesity")

Height (length) — Height (length) is measured at each periodic well-child visit. Children younger than two years and older children who are unable to stand should be measured in the supine position (length) because standing measurements (height) are unreliable (figure 3). Children older than two years who are able to stand should be measured while standing (figure 4).

The length or height for age are compared with growth standards:

●For children <2 years (figure 5A-B) (calculator 2)

●For children ≥2 years (figure 6A-B) (calculator 3 and calculator 4)

The evaluation of children with abnormal height (length) is discussed separately. (See "Diagnostic approach to children and adolescents with short stature" and "The child with tall stature and/or abnormally rapid growth".)

Head circumference

●When to measure – Occipitofrontal circumference (OFC) should be measured in all children at health maintenance visits between birth and three years of age. OFC should also be measured at each visit in children of all ages with neurologic or developmental complaints.

Measurement of OFC in the newborn may be unreliable until the third or fourth day of life since it may be affected by caput succedaneum, cephalohematoma, or molding [5].

●Measuring technique – The measuring tape should encircle the head and include an area 1 to 2 cm above the glabella anteriorly (ie, just above the eyebrows) and the most prominent portion of the occiput posteriorly (picture 1).

In older infants, the accuracy of the measurement may be affected by thick hair and deformation or hypertrophy of the cranial bones.

●Normal head growth – Normal head growth in infants and children is discussed separately. (See "Normal growth patterns in infants and prepubertal children", section on 'Head growth'.)

●Reference standards – OFC should be plotted on a standardized head circumference chart. A disproportionately large head may be indicative of hydrocephalus or macrocephaly. A disproportionately small head may be indicative of neurologic deficits or microcephaly, although in some children a small head size is normal. (See "Macrocephaly in infants and children: Etiology and evaluation", section on 'Etiology' and "Microcephaly in infants and children: Etiology and evaluation".)

It may be inappropriate to use a single head circumference standard for children in all countries or ethnic groups. A study that compared mean head circumference from a variety of studies including >11,000,000 children from economically advantaged populations (1988 to 2013) with the World Health Organization (WHO) reference standards found that the mean head circumferences in certain national or ethnic groups were sufficiently different from the WHO means to affect diagnosis of microcephaly or macrocephaly [6].

Standardized charts for monitoring OFC in children between 0 and 18 years of age include [7-10]:

•For routine measurement in children younger than two years – The Centers for Disease Control and Prevention (CDC) recommends that the WHO child growth standards be used for children 0 to 2 years (figure 7A-B) (calculator 5) [10].

The WHO child growth standards for children 0 to 5 years of age are based on data from the Multicentre Growth Reference Study of breastfed children living under optimal environmental conditions.

•For routine measurement in children between age two and three years – The CDC recommends that the CDC growth charts be used for children older than two years (figure 8A-B) (calculator 6) [10].

These charts are based on a nationally representative demographic sample.

•For individuals older than three years with concerns about microcephaly or macrocephaly – The following OFC reference standards are available for children in whom there are concerns about microcephaly or macrocephaly:

-The Nellhaus head circumference charts for children 0 to 18 years of age – These charts are based on a 1968 international meta-analysis [7]. They are available in the full text of the reference [7].

-The Fels head circumference charts for children 0 to 18 years – These charts are based on data from the Fels Longitudinal Study of 888 White children from the United States [8]. They are available in the full text of the reference [8].

-The United States Head Circumference Growth Reference charts for children 0 to 21 years of age – These charts combine growth reference data from the CDC, Nellhaus, the Fels Longitudinal Study, and others [9]. They are available in the full text of the reference [9].

-The Bushby charts for adults – These charts are based on data from 354 White adults (median age 40 years, range 17 to 83 years) in two British centers; OFC percentiles are related to height [11]. Bushby charts are available in the full text of the reference [11].

●Special populations

•Premature infants – Most clinicians use the standard growth curves to monitor the head growth of premature infants, with correction for gestational age), until approximately 18 to 24 months of age [12]. (See "Growth management in preterm infants", section on 'Monitoring of growth'.)

•Children with conditions associated with macrocephaly – The standard growth curves are not appropriate for monitoring the head size of children with certain medical conditions associated with macrocephaly (eg, achondroplasia, neurofibromatosis). (See "Achondroplasia", section on 'Management' and "Neurofibromatosis type 1 (NF1): Pathogenesis, clinical features, and diagnosis".)

•Children with conditions associated with microcephaly – The standard growth curves are not appropriate for monitoring the head size of children with craniosynostosis, craniofacial syndromes, and children with certain medical conditions associated with microcephaly (eg, Williams-Beuren syndrome). Growth curves for children with Williams-Beuren syndrome are available through the American Academy of Pediatrics.

Chest circumference — Chest circumference is measured at the time of the newborn examination, but it is not a part of the routine examination for well-child visits. The chest circumference is measured at the nipple line. Chest circumference is 1 to 2 cm smaller than head circumference in most newborns and children 12 to 18 months old. Provided that the head circumference is in the normal range for age and sex, if the chest circumference is more than 2 cm smaller or larger than the head circumference, examination of the chest wall and imaging of the thoracic cavity may be warranted (eg, to evaluate asphyxiating thoracic dystrophy, pectus excavatum, pectus carinatum) [13]. (See "The pediatric physical examination: Chest and abdomen", section on 'Chest wall' and "Chest wall diseases and restrictive physiology", section on 'Congenital and childhood abnormalities'.)

Vital signs

Temperature — Routine measurement of the patient's temperature is not always necessary. When a temperature measurement is needed, appropriate site for measurement varies with age, ability to cooperate, and clinical scenario. Temperature measurement techniques and indications are discussed separately. (See "Fever in infants and children: Pathophysiology and management", section on 'Temperature measurement'.)

Respiratory rate — The respiratory rate varies with activity in infants and young children, and in these patients is best assessed by counting for a full 60 seconds [14-17]. Accurate determination of the respiratory rate should be attempted only when the patient is asleep or at rest. It can be obtained by auscultation, palpation, or direct observation. Observation of chest wall movements is preferable to auscultation because auscultation may stimulate the child, falsely elevating the rate [14].

The normal range for the respiratory rate depends upon the age of the child. A systematic review of 20 studies provided respiratory rate percentiles for healthy children who were typically awake and at rest (table 1) [18]. A sustained breathing rate in excess of the upper limit of normal generally indicates primary respiratory tract disease; it may also occur secondary to a metabolic disorder, infectious disease, high fever, or underlying heart disease. Although the respiratory rate may increase with fever [19-21], the relationship between temperature and respiratory rate is not linear. Thus, a simple rule for use in clinical decision making is not possible.

Heart rate — The heart rate can be measured by direct auscultation or palpation of the heart or by palpation of peripheral arteries (carotids, femorals, brachial, or radials).

Like the respiratory rate, the normal heart rate varies with age. A systematic review of 59 studies provided heart rate percentiles for healthy children who were typically awake and at rest (table 1) [18]. A heart rate above the upper limit of normal may indicate primary cardiac disease; it also can occur secondary to an underlying systemic or metabolic disorder, infectious disease, or high fever.

Blood pressure — Blood pressure should be measured annually at well-child visits for all children age three years and older, and more frequently in those with risk factors for hypertension.

Blood pressure generally is not measured in children younger than three years unless they have evidence of underlying renal disease (eg, tumor, nephrotic syndrome, glomerulonephritis, pyelonephritis, renal artery stenosis), suspicion of acute cardiovascular disease (eg, coarctation of the aorta, patent ductus arteriosus), or acute illness. Obtaining an accurate blood pressure reading in children younger than three often is difficult. (See "Clinical manifestations and diagnosis of coarctation of the aorta" and "Clinical manifestations and diagnosis of patent ductus arteriosus (PDA) in term infants, children, and adults".)

Blood pressure devices include the standard extremity cuff and mercury bulb sphygmomanometer, the hand-held aneroid manometer, and the Doppler and oscillometric devices. Patients old enough to understand should be shown the blood pressure device before the examiner attempts to take a measurement. The patient should be allowed to play with the device or feel the cuff inflate to gain their cooperation. The proper technique for blood pressure measurement is discussed separately. (See "Definition and diagnosis of hypertension in children and adolescents", section on 'Measurement of blood pressure'.)

As with pulse and respiratory rates in children, blood pressure varies with age and height percentile. Standard reference charts that give the ranges of normality should be consulted (table 2A-B) [22].

The systolic pressure measured in the lower extremity generally is approximately 20 mmHg higher than that measured in the upper extremity. Definitions for hypertension in children in the United States (table 3) and other countries are provided separately. (See "Definition and diagnosis of hypertension in children and adolescents".)

●Elevated blood pressure – In addition to the disorders mentioned above, elevated blood pressures are associated with neuroblastomas, pheochromocytomas, thyroid disease, neurofibromatosis, Cushing disease, intoxication from or ingestion of various substances, increased intracranial pressure, and myriad other disorders. It is wise to keep in mind that elevated systolic pressures alone frequently are noted in patients after vigorous exercise, excessive agitation, or during febrile illnesses. (See "Epidemiology, risk factors, and etiology of hypertension in children and adolescents", section on 'Secondary hypertension'.)

●Low blood pressure – Abnormally low blood pressure recordings are noted in patients with heart failure from numerous causes and in patients in shock from causes such as sepsis or hypovolemia. A rapid change in the patient's position from supine to standing or sitting may result in orthostatic hypotension. (See "Initial evaluation of shock in children".)

●Pulse pressure – Pulse pressure is the difference between systolic and diastolic blood pressure.

•Wide pulse pressure – Widened pulse pressures can occur in patients with aortic regurgitation, arteriovenous fistulas, patent ductus arteriosus, or hyperthyroidism. (See "Aortic regurgitation in children" and "Clinical manifestations and diagnosis of patent ductus arteriosus (PDA) in term infants, children, and adults" and "Clinical manifestations and diagnosis of Graves disease in children and adolescents".)

•Narrow pulse pressure – Narrowed pulse pressures are found in patients with subaortic or aortic valve stenosis and occasionally in those with hypothyroidism. (See "Subvalvar aortic stenosis (subaortic stenosis)" and "Valvar aortic stenosis in children" and "Acquired hypothyroidism in childhood and adolescence".)

SUMMARY

●General appearance – Assessment of the general appearance should include the child's state of well-being, activity level, physical appearance, behavior and attitude, body habitus, nutritional status, preferred position (particularly for ill-appearing children), pitch and intensity of the cry (in crying infants), breathing pattern, skin color, and developmental status. (See 'General appearance' above.)

●History – The history is generally obtained from the caregiver for infants and preschool children. Children aged 5 through 12 may contribute to the history if they are willing and able. Adolescent patients should be interviewed in the absence of caregivers when appropriate. (See 'History' above.)

●Physical examination – The order in which the physical examination is conducted often is age specific and depends upon examiner preference. The portions of the examination that require the most cooperation usually are performed first, and the more bothersome portions are performed last. If the patient has a localized complaint, sign, or symptom, that part of the examination should generally be performed last. (See 'Physical examination' above.)

●Standard measurements – Measurement of the weight, length/height, and head circumference is essential for assessing normal development. Data obtained should be plotted on standard growth curves to determine progress. (See 'Growth parameters' above.)

•Children <2 years of age

-Weight (figure 1A-B)

-Length (figure 3 and figure 5A-B)

-Head circumference (figure 7A-B)

•Children ≥2 years of age

-Weight (figure 2A-B)

-Height (figure 4 and figure 6A-B)

●Vital signs

•Temperature – Routine measurement of the patient's temperature is not always necessary at health supervision visits. When a temperature measurement is needed the appropriate site of measurement varies with age, ability to cooperate, and clinical scenario. (See "Fever in infants and children: Pathophysiology and management", section on 'Temperature measurement'.)

•Respiratory and heart rates – The respiratory rate can be obtained by auscultation, palpation, or direct observation. The heart rate can be measured by direct auscultation or palpation of the heart or peripheral arteries (carotids, femorals, brachial, or radials). Normal values for age are provided in the table (table 1). (See 'Respiratory rate' above and 'Heart rate' above.)

•Blood pressure – Yearly blood pressure measurements are routinely obtained in children ages three years and older. Blood pressure measurements also should be obtained in children younger than three years if there is evidence or suspicion of underlying renal or cardiovascular disease or acute illness. Standard reference values according to height percentile are provided in the tables (table 2A-B). (See 'Blood pressure' above.)