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436 SECTION 8: Pulmonary Disorders REFERENCES The complete reference list is available online at www.TintinalliEM.com. Right main bronchus endotracheal tube intubation with cuff inflated Fogarty catheter passed by endotracheal tube to preferentially tamponade affected lung Left-sided bronchus filling with blood Left-sided bronchus filling with blood FIGURE 63-3. These are examples of techniques to control bleeding from the left lung. A. Selective right main bronchus intubation for left-sided massive hemoptysis. B. Using Fogarty catheter to direct control of hemoptysis coming from affected lung. The same techniques are used to control bleeding from the right lung. [Adapted with permission from Lordan JL, Gascoigne A, Corris PA. The pulmonary physician in critical care. Illustrative case 7: Assessment and management of massive haemoptysis. Thorax 58: 814, 2003. Copyright BMJ Publishing Group.] Acute Bronchitis and Upper Respiratory Tract Infections Cedric W. Lefebvre INTRODUCTION Acute bronchitis is a self-limited respiratory infection causing inflam mation of the large airways characterized by cough without evidence of pneumonia. The common cold is a viral infection of the upper respiratory tract, primarily affecting the nasal mucosa causing congestion, rhinorrhea, and sneezing. Influenza, or the flu, is a respiratory illness with fever, myalgias, cough, and fatigue. The clinical syndromes associ ated with these conditions overlap, and their causative pathogens are often similar. Infections of the upper respiratory tract also cause specific clinical conditions such as otitis media (see Chapter 242, “Ear Disor ders”), pharyngitis and epiglottitis (see Chapter 246, “Neck and Upper Airway”), bronchiolitis (see Chapter 116, “Neonatal Emergencies and Common Neonatal Problems”), tracheitis (see Chapter 126, “Stridor and Drooling in Infants and Children”), and sinusitis (see Chapter 244, “Nose and Sinuses”). ACUTE BRONCHITIS Bronchitis is the ninth most common diagnosis for adult patients pre senting to the ED in the United States 1 and ranks as one of the 10 most common outpatient diagnoses worldwide.2  PATHOPHYSIOLOGY Respiratory viruses are the most common documented causative agent in acute bronchitis 2-4; however, epidemiologic studies are hampered by inadequate specimen sampling. 3 The most common viral isolates are influenza A and B viruses, parainfluenza virus, respiratory syncytial CHAPTER virus, coronavirus, adenovirus, and rhinovirus. 1,3 Bacteria have been detected by polymerase chain reaction in 6% to 15.5% of acute bronchitis cases,3,4 excluding patients with chronic bronchitis, for whom bacte rial detection rates are higher (see Chapter 70, “Chronic Obstructive Pulmonary Disease, ” for management). Haemophilus influenzae and Streptococcus pneumoniae were the most common bacterial isolates. Atypical bacterial species such as Mycoplasma pneumoniae, Bordetella pertussis, and Chlamydia pneumoniae have also been isolated.3,4 Epithelial infection of the bronchi leads to inflammation and thickening of the bronchial and tracheal mucosa. This inflammatory condition results in airflow obstruction and bronchial hyperresponsiveness, which can cause decreased forced expiratory volume in 1 second. These physiologic changes can manifest as cough, wheezing, and dyspnea. Sputum production may or may not be prominent.

ening of the bronchial and tracheal mucosa. This inflammatory condition results in airflow obstruction and bronchial hyperresponsiveness, which can cause decreased forced expiratory volume in 1 second. These physiologic changes can manifest as cough, wheezing, and dyspnea. Sputum production may or may not be prominent. Expectorated sputum is composed of lower respiratory tract secretions along with nasopharyngeal and oropharyngeal secretions, cellular debris, and microorganisms. Discoloration of sputum from clear or white to a yellow or green color may be due to cellular debris or a combination of microorganisms and cellular debris. 5,6  CLINICAL FEATURES The clinical manifestations of acute bronchitis include fever, mild dys pnea, and cough (with or without sputum production) persisting for more than 5 days and lasting up to 3 or 4 weeks. 2 During the first few days of infection, the symptoms of an acute upper respiratory infection and acute bronchitis may be indistinguishable. However, the cough will persist for more than 5 days, and abnormal pulmonary function test ing (e.g., reversible decrease in forced expiratory volume in 1 second) consistent with bronchial hyperresponsiveness can be observed in acute bronchitis. 7-9 Cough due to acute bronchitis can persist for 10 to 20 days. History of yellow or green sputum is a poor predictor of bacterial infection and may be present in patients with acute viral bronchitis.6,8  DIAGNOSIS Acute bronchitis is a clinical diagnosis. Acute bronchitis is diagnosed when acute cough (dry or productive) is present for more than 5 days and when evidence of bacterial pneumonia, acute asthma, and exacer bation of chronic bronchitis is absent. Routine sputum cultures are not necessary. 9 Since bronchitis is a self-limited respiratory disorder, other diagnoses should be considered if cough persists for more than 3 weeks. 9,10 Acute bronchitis and bacterial pneumonia can have very similar clinical characteristics. Unlike acute bronchitis, however, pneu monia is not self-limiting and is associated with significant morbidity and mortality if not treated properly. Therefore, it is important to distinguish between the two respiratory infections, especially in the elderly, among whom distinctive signs and symptoms of pneumonia may be lacking. Tintinalli_Sec08_p0425-0472.indd 436 8/1/19 2:10 PM

ting and is associated with significant morbidity and mortality if not treated properly. Therefore, it is important to distinguish between the two respiratory infections, especially in the elderly, among whom distinctive signs and symptoms of pneumonia may be lacking. Tintinalli_Sec08_p0425-0472.indd 436 8/1/19 2:10 PM CHAPTER 64: Acute Bronchitis and Upper Respiratory Tract Infections 437 If there is suspicion for pneumonia, obtain a chest radiograph. 10 The absence of fever, tachycardia, tachypnea, hypoxia, and abnormalities on chest auscultation makes the diagnosis of pneumonia unlikely. 9-11 As a method of differentiating bacterial from viral etiology in lower respira tory tract infections and reducing unnecessary antibiotic prescribing, both calcitonin and rapid point-of-care molecular viral testing have been advocated as a trigger to guide antibiotic treatment decisions. 12,13 However, large, well-conducted, randomized controlled trials failed to show reduction in unnecessary antibiotic prescriptions using calcitonin (ProAct) 14 or rapid point-of-care molecular viral testing (ResPOC) 15 as decision points.  TREATMENT Antibiotics do not provide significant benefit in patients with acute bronchitis. 15-18 Although patients given antibiotics report shorter mean cough duration and a reduction in days feeling ill, the net benefit is small (approximately ½ day), and adverse effects of antibiotic therapy are significant. 2 Despite the lack of evidence supporting antibiotic use for acute bronchitis in any patient population, the majority of acute bronchitis patients receive antibiotics, especially elderly patients and smokers. 1,10,19-21 Antibiotics should be considered when there is strong suspicion for a specific treatable pathogen (e.g., B. pertussis; see “Pertussis” below). 9,10 Additional study is needed to help clinicians determine which patients with acute bronchitis are most likely to benefit from antibiotic treatment. The routine use of β 2-agonists for acute bronchitis should be avoided.1,10,19,22 However, among patients with evidence of airflow obstruction (wheezing), β 2-agonist use is associated with lower symp tom scores and faster resolution of cough. 22,23 Recent evidence does not support the use of oral corticosteroids in acute bronchitis patients with no history of chronic obstructive pulmonary disease or asthma. 24 Antitussives, expectorants, antihistamines, and mucolytics can be considered for cough relief in acute bronchitis; however, limited quality data exist on the efficacy of these agents. 10,19 Benzonatate and guaifenesin may provide modest cough relief.25 COMMON COLD  EPIDEMIOLOGY The common cold afflicts adults up to two or three times every year, whereas children suffer up to eight colds annually, with peak activity during autumn months. 26,27 Responsible for 26 million missed school days and 23 million lost work days, the common cold generates an enormous economic burden.28  PATHOPHYSIOLOGY Rhinovirus is the most common causal agent for the common cold. 29 Coronavirus and adenovirus infection are also associated with the common cold.30 After these viruses are spread by contact with or inhaling aerosolized secretions from an infected individual, they invade the upper respiratory tract, triggering symptoms as soon as 10 to 12 hours after inoculation.  CLINICAL FEATURES A common cold is commonly characterized by sore throat, malaise, rhinitis, rhinorrhea, and cough, which typically persist for up to 7 days. Fever is more common in children than in adults with the common cold. 31,32 Clinical signs of rhinovirus infection include nasal discharge and hoarse voice.  DIAGNOSIS The diagnosis of the common cold is made on clinical grounds alone, based on the typical symptoms listed earlier.

h typically persist for up to 7 days. Fever is more common in children than in adults with the common cold. 31,32 Clinical signs of rhinovirus infection include nasal discharge and hoarse voice.  DIAGNOSIS The diagnosis of the common cold is made on clinical grounds alone, based on the typical symptoms listed earlier. Consider alternative causes of symptoms, such as allergic rhinitis, sinusitis, nonviral pharyngitis, Epstein-Barr virus, influenza, pertussis, and human immunodeficiency virus seroconversion illness.  TREATMENT The goal of treatment for the common cold is supportive care. Decon gestants and antihistamines provide modest symptom improvement in some adults with the common cold. 32-34 Topical nasal decongestants such as oxymetazoline provide moderate benefit in reducing nasal air way resistance.26,31,35 Cough and cold preparations are associated with harm in young children and should be avoided in children age 6 years or younger. Natural remedies are widely advertised by manufacturers and used by patients, although strong evidence to support their use is lacking. Vitamin C, zinc, and Echinacea are purported to decrease the duration, frequency, and symptoms of the common cold. Studies examining their efficacy have had mixed and inconclusive results. 37,38 INFLUENZA  EPIDEMIOLOGY The Centers for Disease Control and Prevention estimates that influenza has afflicted 9 to 60 million people and caused 12,000 to 56,000 deaths annually since 2010. 39 In 2009, a swine-origin H1N1 influenza strain resulted in the century’s first global pandemic. 39-41 This event signaled the emergence of a new pandemic threat, underscoring the importance of understanding the epidemiology of influenza and its potential to impact global health. Influenza viruses are unique pathogens because their evolution involves a complex process of antigenic shifts and spo radic cross-species transmissions between humans, swine, and birds. The intensity of seasonal influenza varies from one year to the next, and localized influenza outbreaks can occur during interpandemic years.  PATHOPHYSIOLOGY The Orthomyxoviridae family includes a diverse array of influenza viruses capable of causing seasonal, endemic, and pandemic infections. Influenza viruses A and B account for most seasonal influenza epidem ics. 39,43 Direct contact and droplet transfer are the predominant modes of transmission for influenza into the upper respiratory tract.44 The incubation period for influenza is 1 to 4 days. Complications of influenza infection include primary influenza viral pneumonia, secondary bacterial pneumonia, and severe hypoxemic respiratory failure. 45 The mortality associated with influenza infection rises in patients with immunosup pression and bacterial coinfection.46 Children with influenza-associated pneumonia are more likely than children admitted for influenza illness to develop respiratory failure and require intensive care unit admis sion. 47 Influenza is also a significant cause of morbidity and mortality in pregnant and postpartum women.48,49  CLINICAL FEATURES Influenza infection is characterized by abrupt onset of fever, chills, malaise, headache, dry cough, sore throat, myalgias, rhinitis, and fatigue. Oropharyngeal irritation and mild cervical lymphadenopathy may be present. Fever and intense myalgias are generally more prevalent dur ing influenza infection than other viral upper respiratory infections. Up to one third of patients do not have fever. 50 Healthy individuals with uncomplicated influenza illness generally experience resolution of symptoms in 3 to 7 days, although cough and malaise may persist beyond 2 weeks.  DIAGNOSIS During seasonal influenza outbreaks, most cases of influenza can be diagnosed on clinical grounds alone.

patients do not have fever. 50 Healthy individuals with uncomplicated influenza illness generally experience resolution of symptoms in 3 to 7 days, although cough and malaise may persist beyond 2 weeks.  DIAGNOSIS During seasonal influenza outbreaks, most cases of influenza can be diagnosed on clinical grounds alone. Testing should be performed on patients in whom results will influence management, such as hospital ized patients, pregnant women, and patients at higher risk for complications (Table 64-1). When testing for influenza, specimens should be obtained as close to symptom onset as possible, and nasopharyngeal swabs or aspirates are preferred. 51 Commercially available rapid influenza diagnostic tests are the most practical in ambulatory settings. However, with reported Tintinalli_Sec08_p0425-0472.indd 437 8/1/19 2:10 PM

ing for influenza, specimens should be obtained as close to symptom onset as possible, and nasopharyngeal swabs or aspirates are preferred. 51 Commercially available rapid influenza diagnostic tests are the most practical in ambulatory settings. However, with reported Tintinalli_Sec08_p0425-0472.indd 437 8/1/19 2:10 PM 438 SECTION 8: Pulmonary Disorders TABLE 64-1 Persons at Higher Risk for Complications of Influenza Infection •  Children  <5 y (especially <2 y) •  Adults  ≥65 y •  Persons  with chronic illnesses and/or conditions* •   Persons with immunosuppression, including secondary to human immunodeficiency virus infection or medications •  Women  who are pregnant or postpartum (within 2 wk of delivery) •  Persons  <18 y receiving long-term aspirin therapy •  Residents  of nursing homes and other chronic care facilities •  Persons  who are morbidly obese (body mass index ≥40 kg/m2) •  American  Indians/Alaska Natives *Includes persons with chronic pulmonary (including asthma, cystic fibrosis), cardiovascular (except hypertension alone), renal, hematologic (including sickle cell disease), and hepatic diseases; metabolic disorders (including diabetes mellitus); cancers; or neurologic and neurodevelopment conditions including disorders of the brain, spinal cord, peripheral nerve, and muscle such as cerebral palsy, epilepsy (seizure disorders), stroke, intellectual disability (mental retardation), moderate to severe developmental delay, muscular dystrophy, or spinal cord injury. TABLE 64-2 Rapid Influenza Testing Modalities Test Time to Results Comments Rapid influenza test– antigen detection (EIA) <15 min Sensitivity  <80% in adults;  followup testing  with RT-PCR should be considered to confirm negative result Rapid molecular assay (influenza viral RNA or nucleic acid detection) 15–30 min Detects influenza viral RNA or nucleic acids with higher sensitivity than rapid antigen detection tests (range 66%–94%) RT-PCR 2 h High sensitivity and specificity; highly recommended test for influenza Abbreviations: EIA = enzyme immunoassay; RNA = ribonucleic acid; RT-PCR = reverse transcription polymerase chain reaction. TABLE 64-3 Antiviral Medications for Influenza: Dosing Medication Treatment Chemoprophylaxis Oseltamivir (Tamiflu®) 75 milligrams orally twice daily × 5 d * 75 milligrams orally once daily × 7 d † Zanamivir (Relenza®) 10 milligrams (2 inhalations) twice daily × 5 d * 10 milligrams (2 inhalations) once daily × 7 d † Peramivir (Rapivab®) 600 milligrams IV over 15 to 30 minutes as a single dose No current recommendation for chemoprophylaxis Baloxavir Marboxil ‡ (Xofluza®) 40 milligrams single dose (two 40-milligram pills if weight over 80 kg) No current recommendation for chemoprophylaxis *Longer courses can be considered for patients who remain severely ill after 5 days of treatment. †For controlling outbreaks in long-term care facilities, the Centers for Disease Control and Prevention recommends a minimum of 2 weeks of chemoprophylaxis and up to 1 week after the last identified case, and 7 days after most recent known exposure in other cases. ‡Initial studies did not establish safety in pregnancy,   patients <12 or >65 years of age. sensitivities of <80%, rapid antigen detection influenza tests do not completely exclude infection.52,53 A study of a rapid molecular assay reported sensitivities of over 90% for both influenza A and B; however, specificity was only 54% to 63% (Table 64-2). 54-56  TREATMENT The antiviral neuraminidase inhibitors available in the United States for treating and preventing influenza A and B infections include oral oseltamivir, inhaled zanamivir, and intravenous peramivir (Table 64-3).

ver 90% for both influenza A and B; however, specificity was only 54% to 63% (Table 64-2). 54-56  TREATMENT The antiviral neuraminidase inhibitors available in the United States for treating and preventing influenza A and B infections include oral oseltamivir, inhaled zanamivir, and intravenous peramivir (Table 64-3). Antiviral treatment for influenza infection within 48 hours of symptom onset shortens the duration of influenza symptoms (0.5 to 1 day), but increases the risk of nausea and vomiting (4% to 5%) and psychiatric symptoms (hallucinations, abnormal behavior; 1%). 57 Approved in 2018, baloxavir marboxil inhibits an endonuclease involved in viral RNA replication. 58 Single dose treatment with baloxavir reduces symptom duration (see Table 64-3), providing a benefit similar to oseltamivir, but may have 4% fewer side effects. 58 Antiviral treatment may reduce the risk of complications and reduce mortality in hospitalized patients,59,60 but these benefits have been challenged.61,62 Antiviral medication should be started as early as possible, preferably within 48 hours of illness onset, in patients with confirmed or suspected influenza infection who are hospitalized, have severe or progressive illness, and are at higher risk for influenza complications (Table 64-2). 63 Antiviral treatment can provide benefit even after 48 hours in pregnant and other high-risk patients.64,65 Recommendations for the treatment of influenza are updated fre quently based on epidemiologic data and antiviral resistance patterns. Consult the Centers for Disease Control and Prevention for the latest updates on influenza treatment guidelines including pharmacotherapy, patient selection, dosing, and prophylaxis. 66 Annual vaccination is recommended for all persons aged 6 months and older because it is the most effective method of preventing influenza illness and decreasing all-cause mortality in those infected with influenza. 67-70 PERTUSSIS Pertussis, or “whooping cough, ” is an acute respiratory infection in humans caused by the aerobic gram-negative rod B. pertussis. Pertussis toxins cause respiratory epithelial and mucosal injury and interfere with immune cell function. Pertussis pneumonia can occur in children, but in school-age children, adolescents, and adults, upper respiratory infections are the rule.  IMMUNIZATION Although pertussis is often considered a disease of infants (primarily in those <1 year old who have not completed three doses of vaccination) and a disease in developing countries where immunization is not uni versal, in North America, the disease is now more common in schoolage children and adults. School-age children are the usual sources of infection, and adults may serve as carriers of disease. Cyclical outbreaks occur every 3 to 5 years. 71 However, the incidence and deaths due to pertussis have decreased over the past 20 years.72 There are two types of vaccines, whole cell and acellular. Wholecell pertussis vaccination is effective for about 10 years and is used in developing nations. The acellular diphtheria, tetanus, and pertussis vaccine (DTaP), developed to remove toxins from the cell membrane, does not protect as long as the whole-cell vaccine and is typically used in the developed world. 73 The typical immunization schedule is at 2, 4, 6, and 18 months of age with a booster at age 5. Adolescents should receive a DTaP booster. Pregnant women should receive a booster of DTaP to protect neonates and infants and to prevent infection in the mother. For the unimmunized elderly (>65 years old), one dose of DTaP is recommended.

unization schedule is at 2, 4, 6, and 18 months of age with a booster at age 5. Adolescents should receive a DTaP booster. Pregnant women should receive a booster of DTaP to protect neonates and infants and to prevent infection in the mother. For the unimmunized elderly (>65 years old), one dose of DTaP is recommended. 74 Although the vaccine is specifically not registered for the elderly, 75 a study of nearly 120,000 individuals ≥65 years old did not demonstrate any increase in inflammatory or allergic events in those receiving DTaP compared with those receiving only the tetanus and diphtheria vaccine. 76 There is no lifelong immunity after a clinical episode of pertussis.  CLINICAL FEATURES Clinical features in adults are those of the common cold, but after 1 week, prolonged, paroxysmal, and sleep-disturbing cough develops. Whooping is uncommon in adults. Consider pertussis in situations of chronic cough >2 weeks in duration. Cough may last for several months. Since pertus sis is highly communicable, with an attack rate of about 20% even in the immunized, suspect pertussis if there is contact with other individuals with prolonged cough. Except in the elderly, pertussis in adults is not associated with pneumonia. Clinical or radiologic evidence of pneumonia in adults or the elderly suggests secondary bacterial infection. Tintinalli_Sec08_p0425-0472.indd 438 8/1/19 2:10 PM