SEMIOTICS OF THE RESPIRATORY SYSTEM DISEASES. THE RESPIRATORY DISTRESS SYNDROMES AND

SEMIOTICS nOF THE RESPIRATORY SYSTEM DISEASES. THE RESPIRATORY DISTRESS SYNDROMES AND

RESPIRATORY nFAILURE, GENERAL CLINICAL SYMPTOMS

 

Acute viral infections of respiratory tracts

Acute viral infections of nrespiratory tracts (AVIR) are a group of diseases of the upper and nmedium respiratory tracts, mostly of virus (H. Influenzae, parainfluenzae, nadeno- and rhino-viruses, virus-ECHO, etc), sometimes of microbial (B-hemolytic nstreptococcus of group A, pneumococcus) etiology. I ocal manifestations of AVIR are: rhinitis, pharyngitis, laryngitis; nin most cases bronchitis in children is also considered as AVIR.

 

Acute rhinitis is the inflammation of mucous nmembrane of the nose, mostly of viral etiology.

Clinical manifestations:

•   Sneezing.

•   Complicated nnasal respiration.

•   The nexcretion of mucus from the nose (at the beginning serous, watery, themore thick).

• Cough (it is caused by the irritation of the back nwall of pharynx by mucus refluxing from the nose).

• The general manifestations — weakness, headache, nfever; at breast-feeding age — complicated process of sucking.

 

The acute pharyngitis is an inflammation of the nmucous membrane of oropharynx — can be both of viral and bacterial etiology. Ithe latter case, it is often caused by p-hemolytic streptococcus of group A, nwhich can be a factor of rheumatic fever, glomerulonephritis.

Clinical manifestations:

• Hyperemia of the pharynx.

• Increased follicle on the back wall of oropharynx— na symptom of ‘cobblestone road’.

• Pain at swallowing.

• Coughing.

• General manifestations of intoxication.

In children of early age AVIR can be complicated nwith otitis (explain the anatomic reason).

 

Acute laryngitis, is an inflammation of the mucous nmembrane of the larynx of viral or bacterial etiology. Children under 3 years nof age with laryngitis have stenosis (i.e. narrowing) of the opening of larynx, nwhich is caused by the anatomic features at this age recollect. The developing nsyndrome refers to ‘false croup ( pseudo-croup)’ and the diagnosis is nconstrictive laryngotracheitis.

Clinical manifestations:

•        n’Barking’ cough.

•        A hoarse nvoice, in severe cases — aphonia.

•        nInspiratory dyspnea (explain the reason and its sign).

•        nTachycardia.

•        nWeakness, lethargy, acute laryngitis which is often interchangeable with nrestlessness.

•        The ngeneral manifestations, characteristic for intoxication.

The development of false croup is dangerous for life nof the child as in the? neglected cases, the progressing stenosis can lead to nasphyxia — the pathological condition menacing the life in theform of nsuffocation. Simultaneously, tachycardia is replaced by bradycardia, and theheart failure follows. The only way of treatment is intubation or tracheostomy.

 

Croup is a common, primarily pediatric viral nrespiratory tract illness. As its alternative names, laryngotracheitis and nlaryngotracheobronchitis, indicate, croup generally affects the larynx and ntrachea, although this illness may also extend to the bronchi. It is the most ncommon etiology for hoarseness, cough, and onset of acute stridor in febrile nchildren. Symptoms of coryza may be absent, mild, or marked. The vast majority nof children with croup recover without consequences or sequelae; however, it ncan be life-threatening.

Croup manifests as hoarseness, a seal-like barking ncough, and a variable degree of respiratory distress. However, morbidity is nsecondary to narrowing of the larynx and trachea below the level of the glottis n(subglottic region), causing the characteristicaudible inspiratory stridor.

Stridoris a common symptom in patients with croup. nThe acute onset of this abnormal sound alarms parents enough to prompt aurgent care or emergency department (ED) visit. Stridor is an audible harsh, nhigh-pitched, musical sound produced by turbulent airflow through a partially nobstructed upper airway. This partial airway obstruction can be present at the nlevel of the supraglottis, glottis, subglottis, and/or trachea. During ninspiration, areas of the airway that are easily collapsible (eg, supraglottic nregion) are suctioned closed because of negative intraluminal pressure ngenerated during inspiration. These same areas are forced open during nexpiration.

Depending on timing within the respiratory cycle, nstridor can be heard on inspiration, expiration, or in both (biphasic; ninspiratory and expiratory). Inspiratory stridor suggests a laryngeal nobstruction, whereas expiratory stridor suggests tracheobronchial obstruction. nBiphasic stridor indicates either a subglottic or glottic anomaly. An acute nonset of marked inspiratory stridor is one of the hallmarks of croup; however, nthere also may be less audible expiratory stridor.

Young children who present with stridor require a nmeticulous evaluation to determine the etiology and, most importantly, to nexclude rare life-threatening causes. Although croup is usually a mild, nself-limited disease, upper airway obstruction may result in respiratory ndistress and even death.

Physical Examination. The physical presentation of ncroup has wide variation. Most children have no more than a “croupy” ncough and hoarse cry. Some may have stridor only upon activity or agitation, nwhereas others have audible stridor at rest and clinical evidence of nrespiratory distress. Paradoxically, a severely affected child may have “quiet” nstridor secondary to a greater degree of airway obstruction. The child with ncroup typically does not appear toxic.

The child’s symptoms can range from minimal ninspiratory stridor to severe respiratory failure secondary to airway nobstruction.In mild cases, respiratory sounds at rest are normal; however, mild nexpiratory wheezing may be heard. Children with more severe cases have ninspiratory and expiratory stridor at rest with visible suprasternal, nintercostal, and subcostal retractions. Air entry may be poor. Lethargy and nagitation may be due to marked respiratory difficulty and, hence, hypoxemia and nincreasing hypercarbia.

Other warning signs of severe respiratory disease ninclude tachypnea, tachycardia out of proportion to fever, and hypotonia. nChildren unable to maintain adequate oral intake, results in compromised nhydration and can lead to dehydration. Cyanosis is a late, ominous sign.

Croup is primarily a clinical diagnosis, with the ndiagnostic clues based on presenting history and physical examination findings. n

Laboratory test results rarely contribute to nconfirming this diagnosis. The complete blood cell (CBC) count is usually nnonspecific, although the white blood cell (WBC) count and differential may nsuggest a viral cause with lymphocytosis. Identifying the specific viral netiology (eg, parainfluenza virus serotype, respiratory syncytial virus [RSV]) nvia nasal washings is typically not necessary but may be useful to determine nisolatioeeds in the hospital care setting or, in the case of influenza A, to ndecide whether antiviral therapy should be initiated.

Pulse oximetry readings are within the normal nreference range for most patients; however, this monitoring is helpful to nassess for the need for supplemental oxygen support and to monitor for nworsening respiratory compromise as evidentwith tachypnea and poor maintenance nof oxygen saturations. Standardly, arterial blood gas (ABG) measurements are nunnecessary and do not reveal hypoxia or hypercarbia unless respiratory fatigue nensues.

Patients who present with fevers, tachypnea, and nhistory of decreased oral fluid intake require evaluation of their hydratiostatus. Compromised oral intake and inability to maintaieeded fluid volume nmay require intravenous fluid support to stabilize, support and sustain their nongoing fluid requirements.

Procedures

Laryngoscopy is indicated only in unusual ncircumstances (eg, the course of illness is not typical, the child has symptoms nthat suggest an underlying anatomic or congenital disorder). This procedure may nalso be required in patients with bacterial tracheitis to obtain the necessary ncultures in an attempt to tailor antibiotic treatment.

Other procedures that may be indicated and may nrequire the guidance of a pediatric otolaryngologist include the following:

Direct laryngoscopy if the child iot in acute ndistress

Fiberoptic laryngoscopy

Bronchoscopy (for cases of recurrent croup to rule nout airway disorders)

Radiography. Plain films can verify a presumptive ndiagnosis or exclude other disorders causing stridor and hence mimic croup. A nlateral neck radiograph can help detect clinical diagnoses such as an aspirated nforeign body, esophageal foreign body, congenital subglottic stenosis, nepiglottitis, retropharyngeal abscess or bacterial tracheitis (thickened ntrachea).Most importantly, croup is a clinical diagnosis. Radiographs can be nused as a tool to help confirm this diagnosis, but they are not required iuncomplicated cases.

Concurrently, careful monitoring of the heart rate n(for tachycardia), respiratory rate (for tachypnea), respiratory mechanics (for nsternal wall retractions), and pulse oximetry (for hypoxia) are important. nAssessment of the patient’s hydration status, given the risk of increased ninsensible losses from fever and tachypnea, along with a history of decreased noral intake, is also imperative.

Treatment. Urgent care or emergency department ntreatment of croup depends on the degree of respiratory distress. In mild ncroup, a child may present with only a croupy cough and may require nothing nmore than parental reassurance, given alertness, baseline minimal respiratory ndistress, proper oxygenation, and stable fluid status. The caregivers may only nneed education regarding the course of the disease and supportive homecare nguidelines.

However, any infant/child who presents with nsignificant respiratory distress/complaints with stridor at rest must have a nthorough clinical evaluation to ensure the patency of the airway and nmaintenance of effective oxygenation and ventilation. Keep young children as ncomfortable as possible, allowing him or her to remain in a parent’s arms and navoiding unnecessary painful interventions that may cause agitation, nrespiratory distress, and lead to increased oxygen requirements. Persistent ncrying increases oxygen demands, and respiratory muscle fatigue can worsen the nobstruction.

Concurrently, careful monitoring of the heart rate n(for tachycardia), respiratory rate (for tachypnea), respiratory mechanics (for nsternal wall retractions), and pulse oximetry (for hypoxia) are important. nAssessment of the patient’s hydration status, given the risk of increased ninsensible losses from fever and tachypnea, along with a history of decreased noral intake, is also imperative.

Infants and children with severe respiratory ndistress or compromise may require 100% oxygenation with ventilation support, ninitially with a bag-valve-mask device. If the airway and breathing require nfurther stabilization due to increasing respiratory fatigue and hence, nworsening hypercarbia, (as evident by ABG) the patient should be intubated with nan endotracheal tube. Intubation should be accomplished with an endotracheal ntube that is 0.5-1 mm smaller than predicted. Once airway stabilization is nachieved, these patients are transferred for their ongoing care to a pediatric nintensive care unit.

The current cornerstones of treatment in the urgent ncare clinics or emergency departments are corticosteroids and nebulized nepinephrine; steroids have proven beneficial in severe, moderate, and even mild ncroup. In the straightforward cases of croup, antibiotics are not prescribed, nas the primary cause is viral. Lack of improvement or worsening of symptoms cabe due to a secondary bacterial process, which would require the use of nantimicrobials for treatment. Typically, these patients initially would have had nmoderate-to-severe croup scores, requiring inpatient care and observation.

 

Epiglottitis, also termed supraglottitis or nepiglottiditis, is an inflammation of structures above the insertion of the nglottis and is most often caused by bacterial infection. Before widespread Haemophilus ninfluenzae type b (Hib) vaccination, H influenzae caused almost all pediatric ncases of epiglottitis.

Affected structures include the epiglottis, naryepiglottic folds, arytenoid soft tissue, and, occasionally, the uvula. The nepiglottis is the most common site of swelling. Acute epiglottitis and nassociated upper airway obstruction has significant morbidity and mortality and nmay cause respiratory arrest and death.

The following image illustrates the difference nbetween a normal pediatric airway and one from a child with fatal epiglottitis.

Complications

During the bacteremic phase of the disease, other nfoci of infection are possible. Pneumonia is the most commonly cited associated nillness, followed by otitis media. Meningitis has also been reported iassociation with epiglottitis.

As with other causes of upper airway obstruction, npulmonary edema can be observed after the airway has been secured. Accidental nextubation and respiratory arrest are the 2 most common complications, and naccidental extubation can cause additional complications. Cervical adenitis, tonsillitis, nand otitis media have also been documented.

In summary, complications associated with a swolleepiglottis and surrounding tissues include airway obstruction, which can lead nto respiratory arrest and death from hypoxia as well the following:

·        nAspiration

·        nEndotracheal tube dislodgement

·        nExtubation

·        Tracheal nstenosis

·        nPneumothorax or pneumomediastinum

·        nEpiglottic abscess

·        Adenitis

·        Cervical ncellulitis

·        Septic nshock

·        Pulmonary nedema (rare)

·        Cerebral nanoxia

·        Death nfrom asphyxia

In classic cases involving bacteremia with Haemophilus ninfluenzae, other structures may have concomitant infectious processes. These nmay include the following:

·        nMeningitis

·        nPneumonia

·        nSepticemia

·        nCellulitis

·        Septic narthritis

·        Otitis nmedia

·        nPericarditis (rare)

Physical Examination. The child appears toxic; shock nmay occur early in the course of the disease. Marked restlessness, nirritability, and extreme anxiety are common. The child may sit with his or her nchin hyperextended and body leaning forward (ie, tripod or sniffing position) nto maximize air entry and improve diaphragmatic excursion (see the following nimage).The mouth may be open wide and the tongue may protrude; an affected nchild often drools, because swallowing is difficult or painful. An erythematous nand classic swollen, cherry red epiglottis can often be seen during careful nexamination of the oropharynx, although this examination should not be nattempted if it may compromise respiratory effort. Early on, the child may have nstridulous respirations, but as the disease progresses, airway sounds may ndiminish. Stridor can occur with marked suprasternal, subcostal, and nintercostal retractions. Anterior neck examination may reveal tender nadenopathy. In the older child, pain may be noted on movement of the hyoid bone. nCyanosis, which occurs late in the course of the condition, indicates a poor nprognosis. Securing an airway is the overriding priority. An expert ipediatric airway management should always perform an endotracheal intubation oany child with suspected epiglottitis before radiography or blood work is nperformed. 

Workup. Laryngoscopy is the best way to confirm the ndiagnosis, but it is not advised to attempt any procedures without securing the nairway. Simply depressing the child’s tongue with a tongue blade may visualize nthe epiglottitis in some situations. Some concern exists regarding the safety nof such procedures, which can provoke anxiety and increased respiratory effort nduring examination leading to airway obstruction.

Laboratory evaluation is nonspecific in patients nwith epiglottitis and should be performed once the airway is secured. The white nblood cell (WBC) count may be elevated from 15,000-45,000 cells/µL with a npredominance of bands. Histologic examination reveals massive infiltration with npolymorphonuclear leukocytes and inflammatory edema.

Classic cases of epiglottitis require no nradiographic evaluation; however, radiography may be needed in some cases to nconfirm the diagnosis and to exclude other potential causes of acute airway nobstruction. When radiography is required to exclude other diagnoses, perform nportable radiography at the patient’s bedside.

Recommendations for computed tomography (CT) nscanning of the neck in early or unusual cases have been suggested,although ngreat care should be used because of the positioning of the patient.

If epiglottitis is in the differential diagnosis, nthe child should never be left alone even if imaging studies are being nobtained. The child should always be accompanied by personnel who are able to nachieve rapid airway access if needed.

Fiberoptic Laryngoscopy

Laryngoscopy can help exclude other diagnoses in aolder child who is cooperative. However, do not perform a laryngoscopy if the nprocedure might increase anxiety, which can exacerbate the airway obstruction.

The naris can be anesthetized with lidocaine jelly nbefore inserting the fiberoptic laryngoscope. Insert the laryngoscope through nthe naris, advancing it slowly into the supraglottic region. The epiglottis nshould be easily visualized to determine the presence of swelling.

A study performed in Germany recommended nlaryngoscopy to aid in the diagnosis in patients with atypical presentations or nwith crouplike coughs. This study also showed that fiberoptic endoscopy is nespecially useful in cooperative older children with moderate respiratory ndistress.

Percutaneous Transtracheal Ventilation

Also termed needle cricothyrotomy or translaryngeal nventilation, percutaneous transtracheal ventilation is a temporizing method nused to treat cases of severe epiglottitis when the patient cannot be intubated nbefore a formal tracheostomy.

Percutaneous transtracheal ventilation involves ninserting a needle through the cricothyroid membrane, which lies inferior to nthe thyroid cartilage and superior to the cricoid cartilage. The cricothyroid narteries typically course through the superior portion of the membrane.

Treatment in patients with epiglottitis is directed ntoward relieving the airway obstruction and eradicating the infectious agent. nOptimally, initial treatment is provided by a pediatric anesthesiologist and neither a pediatric surgeon or a pediatric otolaryngologist. Once the airway is ncontrolled, a pediatric intensivist is required for inpatient management.

Avoid procedures that might increase the child’s nanxiety until after the child’s airway is secured. Procedures such as nvenipuncture and intravenous access, although appropriate in most cases ninvolving children with acute epiglottitis, may heighten anxiety and nprecipitate airway compromise.

Do not underestimate the potential for suddedeterioration. As soon as epiglottitis is suspected, initiating and mobilizing na medical and surgical team capable of securing the airway is imperative.

Never place a child in a supine position (other thaduring the endotracheal intubation procedure), because immediate respiratory arrest nin this position has been reported.

 

Acute bronchitis is a clinical syndrome produced by ninflammation of the trachea, bronchi, and bronchioles. In children, acute nbronchitis usually occurs in association with viral respiratory tract ninfection. Acute bronchitis is rarely a primary bacterial infection iotherwise healthy children.

Examples of normal airway color and architecture and nan airway in a patient with chronic bronchitis are shown below.

Normal airway color and architecture (in a child nwith mild tracheomalacia). Airway of a child with chronic bronchitis shows nerythema, loss of normal architecture, and swelling.

Symptoms of acute bronchitis usually include nproductive cough and sometimes retrosternal pain during deep breathing or ncoughing. Generally, the clinical course of acute bronchitis is self-limited, nwith complete healing and full return to function typically seen within 10-14 ndays following symptom onset.

Chronic bronchitis has also been defined as a ncomplex of symptoms that includes cough that lasts more than 1 month or nrecurrent productive cough that may be associated with wheezing or crackles oauscultation. Elements of these descriptors are present in the working ndefinitions of asthma, as well.

Treatment of chronic bronchitis in pediatric npatients includes rest, use of antipyretics, adequate hydration, and avoidance nof smoke.

Analgesics and antipyretics target the symptoms of npediatric bronchitis. In chronic cases, bronchodilator therapy should be nconsidered. Oral corticosteroids should be added if cough continues and the nhistory and physical examination findings suggest a wheezy form of bronchitis.

Acute bronchitis begins as a respiratory tract ninfection that manifests as the common cold. Symptoms often include coryza, nmalaise, chills, slight fever, sore throat, and back and muscle pain.

The cough in these children is usually accompanied nby a nasal discharge. The discharge is watery at first, then after several days nbecomes thicker and colored or opaque. It then becomes clear again and has a nmucoid watery consistency before it spontaneously resolves within 7-10 days. nPurulent nasal discharge is common with viral respiratory pathogens and, by nitself, does not imply bacterial infection.

Initially, the cough is dry and may be harsh or raspy nsounding. The cough then loosens and becomes productive. Children younger tha5 years rarely expectorate. In this age group, sputum is usually seen ivomitus (ie, posttussive emesis). Parents frequently note a rattling sound ithe chest. Hemoptysis, a burning discomfort in the chest, and dyspnea may be npresent.

Brunton et al noted that adult patients with chronic nbronchitis have a history of persistent cough that produces yellow, white, or ngreenish sputum on most days for at least 3 months of the year and for more nthan 2 consecutive years. Wheezing and reports of breathlessness are also ncommon. Pulmonary function testing in these adult patients reveals irreversible nreduction in maximal airflow velocity.

Physical Examination

Lungs may sound normal. Crackles, rhonchi, or large nairway wheezing, if any, tend to be scattered and bilateral. The pharynx may be ninjected.

For maximal cost-effectiveness, diagnostic nlaboratory tests for bronchitis should be performed in a stepwise manner. nPatients with uncomplicated acute respiratory illness who are cared for in aoutpatient setting need little, if any, laboratory evaluation.

Testing in Hospitalized Children

For hospitalized children, serum C-reactive proteiscreen, respiratory culture, rapid diagnostic studies, and serum cold nagglutinin testing (at the appropriate age) help to classify whether the ninfection is caused by bacteria, atypical pathogens (eg, Chlamydia pneumoniae, nMycoplasma pneumoniae), or viruses. Obtain a blood or sputum culture if nantibiotic therapy is under consideration.

For the child admitted to the hospital with a npossible chlamydial, mycoplasmal, or viral lower respiratory tract infectiofor which specific therapy is considered, test nasopharyngeal secretions for nthese pathogens, using antigen or polymerase chain reaction testing for Chlamydia nspecies and respiratory syncytial, parainfluenza, and influenza viruses or nviral culture. Results will guide appropriate antimicrobial selection.

For the child who has been intubated, collect a nspecimen of deep respiratory secretions for Gram stain, chlamydial and viral nantigen assays, and bacterial and viral cultures.

Chest Radiography

Chest films generally appear normal in patients with nuncomplicated bronchitis. Abnormal findings are minimal and may include natelectasis, hyperinflation, and peribronchial thickening. Focal consolidatiois not usually present. These findings are similar to the radiographic findings nin patients with asthma. Radiographic findings may help exclude other diseases nor complications, particularly when abnormalities in either vital signs or npulse oximetry findings are present.

Pulmonary Function Testing

Pulmonary function tests may show airflow nobstruction that is reversible with bronchodilators. Bronchial challenge, such nas with exercise or with histamine or methacholine exposure, may demonstrate nthe airway hyperreactivity characteristic of asthma.

Bronchoscopy

On fiberoptic bronchoscopy, a diagnosis of chronic nbronchitis is suggested if the airways appear erythematous and friable. nBronchoalveolar lavage may be useful in establishing an infectious cause. nBronchoalveolar lavage may reveal numerous monocytic or polymorphonuclear ninflammatory cells. In children with chronic aspiration of gastric contents, nlipids may be present within macrophages.

 

Treatment

Emergency care for acute bronchitis or exacerbatioof chronic bronchitis must focus on ensuring that the child has adequate noxygenation. Outpatient care is appropriate unless bronchitis is complicated by nsevere underlying disease. General measures include rest, use of antipyretics, nadequate hydration, and avoidance of smoke.

Proper care of any underlying disorder is of nparamount importance. Consideration of asthma and adequate therapy are critical nto an early response.

Febrile patients should increase oral fluid intake. nInstruct the patient to rest until the fever subsides.

Resolution of symptoms, normal findings on physical nexamination, and normal pulmonary function test results indicate the end of the nneed for acute treatment. Patients in whom asthma is diagnosed will likely nrequire ongoing therapy for that disease. Patients with defined nhypogammaglobulinemia may need periodic immunoglobulin replacement treatments. nThese are best coordinated with the assistance of a pediatric allergy and nimmunology or pulmonary specialist.

 

Medication Summary

In acute bronchitis, medical therapy generally ntargets symptoms and includes use of analgesics and antipyretics.

In chronic bronchitis, bronchodilator therapy should nbe considered and instituted; either a beta-adrenergic agonist, such as nalbuterol or metaproterenol, or theophylline may be effective. Beta-adrenergic nagents are less toxic, have a more rapid onset of action than theophylline, and ndo not require monitoring of levels. Inhaled corticosteroids may be effective.

In the child who continues to cough despite a trial nof bronchodilators and in whom the history and physical examination findings nsuggest a wheezy form of bronchitis, oral corticosteroids should be added. If nthe response is suboptimal or if fever persists, antibiotic therapy with aagent such as a macrolide or beta-lactamase–resistant antimicrobial may be nconsidered.

Antibiotics should not be the primary therapy. They nusually do not result in a cure and may delay the start of more appropriate nasthma therapies.

 

Pneumonia

Pneumonia and other lower respiratory tract ninfections are the leading causes of death worldwide. Because pneumonia is ncommon and is associated with significant morbidity and mortality, properly ndiagnosing pneumonia, correctly recognizing any complications or underlying nconditions, and appropriately treating patients are important. Although ideveloped countries the diagnosis is usually made on the basis of radiographic nfindings, the World Health Organization (WHO) has defined pneumonia solely othe basis of clinical findings obtained by visual inspection and on timing of nthe respiratory rate.

Pneumonia may originate in the lung or may be a nfocal complication of a contiguous or systemic inflammatory process. nAbnormalities of airway patency as well as alveolar ventilation and perfusiooccur frequently due to various mechanisms. These derangements oftesignificantly alter gas exchange and dependent cellular metabolism in the many ntissues and organs that determine survival and contribute to quality of life. nRecognition, prevention, and treatment of these problems are major factors ithe care of children with pneumonia.

One particular form of pneumonia present in the npediatric population, congenital pneumonia, presents within the first 24 hours nafter birth. For more information

Other respiratory tract diseases such as croup n(laryngotracheobronchitis), bronchiolitis, and bronchitis are beyond the scope nof this article and are not discussed further.

 

Diagnosis

The signs and symptoms of pneumonia are oftenonspecific and widely vary based on the patient’s age and the infectious norganisms involved.

Observing the child’s respiratory effort during a nphysical exam is an important first step in diagnosing pneumonia. The World nHealth Organization (WHO) respiratory rate thresholds for identifying childrewith pneumonia are as follows:

·        Childreyounger than 2 months: Greater than or equal to 60 breaths/min

·        Childreaged 2-11 months: Greater than or equal to 50 breaths/min

·        Childreaged 12-59 months: Greater than or equal to 40 breaths/min

Assessment of oxygen saturation by pulse oximetry nshould be performed early in the evaluation when respiratory symptoms are npresent. Cyanosis may be present in severe cases. Capnography may be useful ithe evaluation of children with potential respiratory compromise.

Other diagnostic tests may include the following:

·        nAuscultation by stethoscope:

The sine qua non for pneumonia has always been the npresence of crackles or rales. Although often present, focal crackles as a nstand-alone physical examination finding is neither sensitive nor specific for nthe diagnosis of pneumonia. Additionally, not all children with pneumonia have ncrackles.

Rales, rhonchi, and cough are all observed much less nfrequently in infants with pneumonia than in older individuals. If present, nthey may be caused by noninflammatory processes, such as congestive heart nfailure, condensation from humidified gas administered during mechanical nventilation, or endotracheal tube displacement. Although alternative nexplanations are possible, these findings should prompt careful consideratioof pneumonia in the differential diagnosis.

Other examination findings suggestive of pneumonia ninclude asymmetry of breath sounds in infants, such as focal wheezing or ndecreased breath sounds in one lung field, and asymmetry of chest excursions, nwhich suggest air leak or emphysematous changes secondary to partial airway nobstruction. Similarly, certain more diffuse lung infections (eg, viral ninfections) may result in generalized crackles or wheezing.

·        nCultures:

In general, blood culture results are positive i10-15% of patients with pneumococcal pneumonia. The percentage is even less ipatients with Staphylococcus infection. However, a blood culture is still nrecommended in complicated cases of pneumonia. It may be the only way to nidentify the pathogen and its antimicrobial susceptibility patterns.

·        nSerology:

Because of the relatively low yield of cultures, nmore efforts are under way to develop quick and accurate serologic tests for ncommon lung pathogens, such as M pneumoniae, Chlamydophila species, and Legionella.

·        Complete nblood cell count (CBC):

Testing should include a CBC count with differential nand evaluation of acute-phase reactants (ESR, CRP, or both) and sedimentatiorate. The total white blood cell (WBC) count and differential may aid idetermining if an infection is bacterial or viral, and, together with clinical nsymptoms, chest radiography, and ESR can be useful in monitoring the course of npneumonia. In cases of pneumococcal pneumonia, the WBC count is often elevated.

·        Chest nradiography:

Chest radiography is indicated primarily in childrewith complications such as pleural effusions and in those in whom antibiotic ntreatment fails to elicit a response. Computed tomography (CT) scanning of the nchest and ultrasonography are indicated in children with complications such as npleural effusions and in those in whom antibiotic treatment fails to elicit a nresponse.

·        nUltrasonography

New data show that point-of-care ultrasonography naccurately diagnoses most cases of pneumonia in children and young adults. nUltrasonography may eventually replace x-rays for diagnosis.

Management

Initial priorities in children with pneumonia ninclude the identification and treatment of respiratory distress, hypoxemia, nand hypercarbia. Grunting, flaring, severe tachypnea, and retractions should nprompt immediate respiratory support. Children who are in severe respiratory ndistress should undergo tracheal intubation if they are unable to maintaioxygenation or have decreasing levels of consciousness. Increased respiratory nsupport requirements such as increased inhaled oxygen concentration, positive npressure ventilation, or CPAP are commonly required before recovery begins.

Antibiotics

The majority of children diagnosed with pneumonia ithe outpatient setting are treated with oral antibiotics. High-dose amoxicilliis used as a first-line agent for children with uncomplicated ncommunity-acquired pneumonia. Second- or third-generation cephalosporins and nmacrolide antibiotics such as azithromycin are acceptable alternatives. nCombination therapy (ampicillin and either gentamicin or cefotaxime) is ntypically used in the initial treatment of newborns and young infants.

Hospitalized patients are usually treated with aadvanced-generation intravenous cephalosporin, often in combination with a nmacrolide. Children who are toxic appearing should receive antibiotic therapy nthat includes vancomycin (particularly in areas where penicillin-resistant npneumococci and methicillin-resistant S aureus [MRSA] are prevalent) along with na second- or third-generation cephalosporin.

Vaccines

Aside from avoiding infectious contacts (difficult nfor many families who use daycare facilities), vaccination is the primary mode nof prevention. Influenza vaccine is recommended for children aged 6 months and nolder. The pneumococcal conjugate vaccine (PCV13) is recommended for all nchildren younger than 59 months old. The 23-valent polysaccharide vaccine n(PPVSV) is recommended for children 24 months or older who are at high risk of npneumococcal disease.

 

Pediatric Airway Foreign Body

Background

The human body has numerous defense mechanisms to nkeep the airway free and clear of extraneous matter. These include the physical nactions of the epiglottis and arytenoid cartilages in blocking the airway, the nintense spasm of the true and false vocal cords any time objects come near the nvocal cords, and a highly sensitive cough reflex with afferent impulses generated nthroughout the larynx, trachea, and all branch points in the proximal ntracheobronchial tree. However, none of these mechanisms is perfect, and nforeign bodies frequently lodge in the airways of children.

Often, the child presents after a sudden episode of ncoughing or choking while eating with subsequent wheezing, coughing, or nstridor. However, iumerous cases, the choking episode is not witnessed, and, nin many cases, the choking episode is not recalled at the time the history is ntaken.

The most tragic cases occur when acute aspiratiocauses total or near-total occlusion of the airway, resulting in death or nhypoxic brain damage.

The more difficult cases are those in which naspiration is not witnessed or is unrecognized and, therefore, is unsuspected.

In these situations, the child may present with npersistent or recurrent cough, wheezing, persistent or recurrent pneumonia, nlung abscess, focal bronchiectasis, or hemoptysis.

If the material is in the subglottic space, symptoms nmay include stridor, recurrent or persistent croup, and voice changes.

In one series, as many as one third of parents were nunaware of the aspiration or remembered an event that occurred more than a week nbefore the presentation.In as many as 25% of cases, aspiration occurred more nthan one month before presentation. Consequently, a high index of suspicion iaddition to the history may be necessary to reach the diagnosis. In another nseries of 280 foreign body aspirations, 47% were detected more than 24 hours nafter the aspiration.However, 99% had signs or symptoms or abnormal plairadiographs before the bronchoscopy.

One of the author’s cases involved a 9-year-old boy nwith persistent pneumonia and lung abscess. Upon bronchoscopy, a plastic toy nwas visualized in his left lower lobe bronchus. Neither he nor his family could nrecognize the toy and had no idea how long it had been since it might have beeaspirated.

Physical

·        Major nfindings include new abnormal airway sounds, such as wheezing, stridor, or ndecreased breath sounds. These sounds are often, but not always, unilateral.

·        Sounds nare inspiratory if the material is in the extrathoracic trachea. If the lesiois in the intrathoracic trachea, noises are symmetric but sound more prominent nin the central airways. These sounds are a coarse wheeze (sometimes referred to nas expiratory stridor) heard with the same intensity all over the chest.

·        Once the nforeign body passes the carina, the breath sounds are usually asymmetric. nHowever, remember that the young chest transmits sounds very well, and the nstethoscope head is often bigger than the lobes. A lack of asymmetry should not ndissuade the observer from considering the diagnosis.

·        nSimilarly, a lack of findings upon physical examination does not preclude the npossibility of an airway foreign body.

Radiography:

Most aspirated foreign bodies are food material and nare radiolucent. Thus, one has to look indirectly for signs of the foreigbody.

Aspirated foreign body (backing to an earring) nlodged in the right main stem bronchus.

Fluoroscopy:

Fluoroscopy of the chest may be helpful in showing nfocal air trapping, paradoxical diaphragmatic motion, or both.

CT scanning:

Chest CT scanning may reveal the material in the nairway, focal airway edema, or focal overinflatioot detected using plairadiography. Even if no foreign body is evident on any of the radiographic nstudies, a foreign body may still be present, and a bronchoscopy should be nperformed if the suspicion is high.

Procedures

Bronchoscopy

If the history and physical findings are diagnostic, nno workup is needed. The child should immediately be referred for rigid nbronchoscopy. Although a flexible bronchoscopy is useful in detecting a foreigbody, removing most foreign bodies using the currently available flexible nbronchoscopes and their attachments is difficult. However, removal using a nfiberoptic bronchoscope has been reported.

If the possiblity of foreign body is significant but nhas not been diagnosed by phyical examination or radiographic studies, flexible nbronchoscopy should be strongly considered.

Heimlich maneuver

If the child has respiratory distress and is unable nto speak or cry, complete airway obstruction is probable, and the likelihood of nmorbidity or mortality is high. In those cases, a Heimlich maneuver may be nperformed. If the child is able to speak, the Heimlich maneuver is ncontraindicated because it might dislodge the material to an area where it ncould cause complete airway obstruction.

Medical Care

·        nBronchodilators and corticosteroids should not be used to remove the foreigbody, and chest physical therapy with postural drainage may dislodge the nmaterial to an area where it may cause more harm, such as at the level of the nvocal cords.

·        nMedications are not necessary before removal, although the endoscopist may nobserve enough focal swelling after the material is removed to recommend a nshort course of systemic corticosteroids.

·        Unless nthe airway secretions are infected with organisms present, antibiotics are not nnecessary.

Surgical Care

·        Surgical ntherapy for an airway foreign body involves endoscopic removal, usually with a nrigid bronchoscope.

Consultations

·        If the ndiagnosis is in question or a flexible bronchoscopy is needed, a pediatric npulmonologist should be consulted.

·        A npediatric surgeon or pediatric otolaryngologist usually performs the rigid nbronchoscopy if necessary.

Medication Summary

No medications are needed. If significant swelling nis observed in the airway or if granulation tissue is present, a corticosteroid n(eg, prednisolone, prednisone) may be administered. Unless airway secretions nare infected, antibiotics are not helpful or necessary.

 

Asthma

Asthma is a chronic inflammatory disorder of the nairways characterized by an obstruction of airflow. Among children and nadolescents aged 5-17 years, asthma accounts for a loss of 10 million school ndays annually and costs caretakers $726.1 million per year because of work nabsence.

Essential update: BPA exposure and risk of childhood nasthma

Results of a prospective birth cohort study of 568 nwomen in the third trimester of pregnancy showed postnatal bisphenol A (BPA) nexposure was associated with significantly increased risk for wheeze and asthma nin offspring at ages 3, 5, and 7 years. Investigators measured urine BPA nconcentrations in mothers and their children to estimate BPA exposure. After nadjusting for secondhand smoke exposure and other asthma risk factors, npostnatal BPA exposure was associated with a 40% to 50% increased risk for nwheeze and asthma. The study also found that exposure during the third ntrimester was inversely associated with risk for wheeze at age 5.

Signs and symptoms

The clinician should establish whether the patient nhas any of the following symptoms:

·        nWheezing: A musical, high-pitched whistling sound produced by airflow nturbulence is one of the most common symptoms of asthma

·        Cough: nUsually, the cough is nonproductive and nonparoxysmal; coughing may be present nwith wheezing

·        Cough at nnight or with exercise: Coughing may be the only symptom of asthma, especially nin cases of exercise-induced or nocturnal asthma; children with nocturnal nasthma tend to cough after midnight, during the early hours of morning

·        nShortness of breath

·        Chest ntightness: A history of tightness or pain in the chest may be present with or nwithout other symptoms of asthma, especially in exercise-induced or nocturnal nasthma

Sputum production

In an acute episode of asthma, symptoms vary naccording to the episode’s severity. Infants and young children suffering a nsevere episode display the following characteristics:

·        nBreathless during rest

·        Not ninterested in feeding

·        Sit nupright

·        Talk iwords (not sentences)

·        Usually nagitated

With imminent respiratory arrest, the child displays nthe aforementioned symptoms and is also drowsy and confused. However, nadolescents may not have these symptoms until they are in frank respiratory nfailure.

Physical examination

Findings during a severe episode include the nfollowing:

·        nRespiratory rate is often greater than 30 breaths per minute

·        nAccessory muscles of respiration are usually used

·        nSuprasternal retractions are commonly present

·        The nheart rate is greater than 120 beats per minute

·        Loud nbiphasic (expiratory and inspiratory) wheezing can be heard

·        Pulsus nparadoxus is often present (20-40 mm Hg)

·        nOxyhemoglobin saturation with room air is less than 91%

Findings in status asthmaticus with imminent nrespiratory arrest include the following:

·        nParadoxical thoracoabdominal movement occurs

·        Wheezing nmay be absent (in patients with the most severe airway obstruction)

·        Severe nhypoxemia may manifest as bradycardia

·        Pulsus paradoxus nmay disappear: This finding suggests respiratory muscle fatigue

Diagnosis

Tests used in the diagnosis of asthma include the nfollowing:

·        nPulmonary function tests: Spirometry and plethysmography

·        Exercise nchallenge: Involves baseline spirometry followed by exercise on a treadmill or nbicycle to a heart rate greater than 60% of the predicted maximum, with nmonitoring of the electrocardiogram and oxyhemoglobin saturation

·        Fractioof exhaled nitric oxide (FeNO) testing: Noninvasive marker of airway ninflammation

·        nRadiography: Reveals hyperinflation and increased bronchial markings; nradiography may also show evidence of parenchymal disease, atelectasis, npneumonia, congenital anomaly, or a foreign body

·        Allergy ntesting: Can identify allergic factors that may significantly contribute to nasthma

·        nHistologic evaluation of the airways: Typically reveal infiltration with ninflammatory cells, narrowing of airway lumina, bronchial and bronchiolar nepithelial denudation, and mucus plugs

Management

Guidelines from the National Asthma Education and nPrevention Program emphasize the following components of asthma care:

·        nAssessment and monitoring: In order to assess asthma control and adjust ntherapy, impairment and risk must be assessed; because asthma varies over time, nfollow-up every 2-6 weeks is initially necessary (when gaining control of the ndisease), and then every 1-6 months thereafter

·        nEducation: Self-management education should focus on teaching patients the nimportance of recognizing their own level of control and signs of progressively nworsening asthma symptoms; educational strategies should also focus oenvironmental control and avoidance strategies, as well as on medication use nand adherence (eg, correct inhaler techniques and use of other devices)

·        Control nof environmental factors and comorbid conditions

·        nPharmacologic treatment

·        Pharmacologic ntreatment

Pharmacologic asthma management includes the use of nagents for control and agents for relief. Control agents include the following:

·        Inhaled ncorticosteroids

·        Inhaled ncromolyn or nedocromil

·        Long-acting nbronchodilators

·        nTheophylline

·        nLeukotriene modifiers

·        nAnti-immunoglobulin E (IgE) antibodies (omalizumab)

Relief medications include the following:

·        nShort-acting bronchodilators

·        Systemic ncorticosteroids

·        nIpratropium

 

Respiratory insufficiency

Process of breathing consists of four stages (I – nexternal, pulmonary respiration, II-IV — internal)

I stage. External respiration is the passage of air nthrough the respiratory ways from the nose up to the alveoli and the process of ngas exchange between the environment and the lungs. External respiration has ntwo functions — enrichment of blood with oxygen (arterialization) and the nremoval of carbon dioxide,

II stage. Transport of oxygen from the lungs to the tissues. n

III stage. Tissue respiration — in microcirculatory nvessels oxygen is given to the tissues

IV stage. Transport of carbon dioxide from the ntissues to the lungs.

Respiratory insufficiency (RI) — it is ainsufficiency of the function of external respiration which leads to hypoxemia— ninsufficient quantity of oxygen in the arterial blood. Thus, respiratory ninsufficiency is a condition during which normal level of oxygen is not nmaintained in the blood. RI can develop in many diseases of the respiratory nsystem (example, laryngitis, bronchitis, pneumonia, asthma, etc.) and is seeas a complication of the main disease.

 

Stages of respiratory insufficiency

 

 

As a result of hypoxemia, hypoxia develops — ninsufficient quantity of oxygen in the body.

 

However do not overlook other reasons of hypoxia:

·      Anemic hypoxia — ninsufficient quantity of hemoglobin in the blood.

·       Circulatory nhypoxia — in arterial blood there is enough oxygen, but its distribution to the ntissues is slowed and in insufficient quantity.

·       Tissue hypoxia n— there is the required quantity of oxygen in the blood and its movement iblood is not impaired, but the tissues are not capable of using it fully (this nfrequently develops due to metabolism disorders).

Respiratory insufficiency is a frequent complicatioof respiratory diseases. Depending on the clinical signs, three stages of RI nare differentiated

 

Respiratory distress syndrome 

Respiratory distress syndrome, also known as hyaline nmembrane disease, occurs almost exclusively in premature infants. The incidence nand severity of respiratory distress syndrome are related inversely to the ngestational age of the newborn infant. (See Etiology and Epidemiology.)

Enormous strides have been made in understanding the npathophysiology and management of respiratory distress syndrome, leading to nimprovements in morbidity and mortality in infants with the condition. Advances ninclude the following (see Treatment and Medication):

·        The use nof antenatal steroids to enhance pulmonary maturity

·        nAppropriate resuscitation facilitated by placental transfusion and immediate nuse of continuous positive airway pressure (CPAP) for alveolar recruitment

·        Early nadministration of surfactant

·        The use nof gentler modes of ventilation, including early use of “bubble” nnasal CPAP to minimize damage to the immature lungs

·        nSupportive therapies, such as the diagnosis and management of patent ductus narteriosus (PDA), fluid and electrolyte management, trophic feeding and nnutrition, and the use of prophylactic fluconazole

These therapies have also resulted in the survival nof extremely premature infants, some of who continue to be ill with ncomplications of prematurity. (See the image below.)

Chest radiographs in a premature infant with nrespiratory distress syndrome before and after surfactant treatment. Left: nInitial radiograph shows poor lung expansion, air bronchogram, and reticular ngranular appearance. Right: Repeat chest radiograph obtained when the neonate nis aged 3 hours and after surfactant therapy demonstrates marked improvement.

Complications

Although reduced, the incidence and severity of ncomplications of respiratory distress syndrome can result in clinically nsignificant morbidities. Sequelae of respiratory distress syndrome include the nfollowing (see Prognosis, Clinical, and Workup):

·        nSepticemia

·        nBronchopulmonary dysplasia (BPD)

·        Patent nductus arteriosus (PDA)

·        nPulmonary hemorrhage

·        nApnea/bradycardia

·        nNecrotizing enterocolitis (NEC)

·        nRetinopathy of prematurity (ROP)

·        nHypertension

·        Failure nto thrive

·        nIntraventricular hemorrhage (IVH)

·        nPeriventricular leukomalacia (PVL) – With associated neurodevelopmental and naudiovisual handicaps

Strategic goals include focusing direct attention oanticipating and minimizing these complications and preventing premature ndelivery whenever possible.

Schematic outlines the pathology of respiratory ndistress syndrome (RDS). Infants may recover completely or develop chronic lung ndamage, resulting in bronchopulmonary dysplasia (BPD). FiO2 = fraction of ninspired oxygen; HMD = hyaline membrane disease; V/Q = ventilation perfusion.

 

 

References

а) Basic

 

1. nManual of Propaedeutic Pediatrics / S.O. Nykytyuk, N.I. Balatska, N.B. Galyash, N.O. Lishchenko, O.Y. Nykytyuk – Ternopil: TSMU, 2005. – 468 pp.

2. Kapitan T. Propaedeutics of children’s diseases nand nursing of the child : [Textbook for students of higher medical educational ninstitutions] ; Fourth edition, updated and

    translated in English / T. Kapitan – Vinnitsa: nThe State Cartographical Factory, 2010. – 808 pp.

3. Nelson Textbook of Pediatrics /edited by Richard nE. Behrman, Robert M. Kliegman; senior editor, Waldo E. Nelson – 19^th ned. – W.B.Saunders Company, 2011. – 2680 p.

 

b) Additional

1.  nwww.bookfinder.com/author/american-academy-of-pediatrics 

2. nwww.emedicine.medscape.com

3. nhttp://www.nlm.nih.gov/medlineplus/medlineplus.html