and upper airway obstruction喘鸣和上呼吸道阻塞课件

Stridor and Upper Airway Obstruction Kevin R Schwartz Massachusetts General Hospital Department of Pediatrics Stridor: Definition Extrathoracic obstruction: -Supraglottic: epiglottitis, retropharyngeal abscess, diptheria, anaphylaxis -Glottic/Subglottic: croup, laryngomalacia, vocal cord paralysis Intrathoracic obstruction: -foreign body aspiration, compression by lymph nodes or tumor, vascular wings/webs Stridor: Differential Diagnosis State the main ideas youll be talking about Viral Croup Pathophysiology: viral infection with measles, parainfluenza type I and 3, influenza A/B, RSV or metapneumovirus causeslaryngo tracheobronchitis. Edema in the subglottic region, which is bound by the cricoid cartilage causes upper airway narrowing. Epidemiology: Mainly affects children aged 6mos to 3yrs with peak incidence in second year of life. Boysgirls. Viral Croup Clinical Presentation: Often antecedent URI symptoms x12-48 hours followed by onset of “barky” characteristic cough, hoarse voice, stridor and respiratory distress, may be accompanied by fever as high as 40 C but patient should NOT drool or appear toxic Physical Examination Findings: Observe pts positioning (?sniffing position), mental status, retractions/flaring, cyanosis, stridor at rest vs. w/ agitation, hydration status, Viral Croup Labs/Studies: Labs uneccessary for diagnsosis and obtaining bloodwork may be distressing to patient, worsening condition. AP and lateral neck radiographs: Viral Croup: Treatment Viral Croup: Treatment Viral Croup: Treatment Bjornson, CL et al. Croup. The Lancet 2008;371:329- 339 d/c home admit Diptheria: Pathophysiology and Epidemiology Pathophysiology: Corynebacterium diptheriae(gram-positive pleomorphic bacillus) infects upper respiratory tract and, after 2-4 days incubation, elaborates a toxin which causes necrosis of mucous membranes and formation of pseudomembranes. The toxin may also affect heart, nerves and kidneys. Epidemiology: endemic in Africa, Asia, South America. V. rare in immunized populations, mostly affecting children 6m/o, with incidence peaking 2-3 y/o Clinical Presentation: Acute onset of stridor in the child with no antecedent illness or fever of the appropriate age group. Labs/Studies: Radio opaque objects may be visible on X ray. Retropharyngeal Abscess: Pathophysiology and Epidemiology Usually an antecedent pharyngitis causes suppuration of retropharyngeal lymph nodes with subsequent abscess formation in the retropharyngeal space. Occur most commonly in children aged 2 to 4y/o, majority of cases occur in children 38.8), severe sore throat, dysphagia and drooling. Child generally appears toxic and generally sits with neck hyperextended and chin thrust forward. Physical Exam: stridor not generally present or not prominent, increase WOB not apparent, but inspiratory distress. Generally, direct visualization of throat is contraindicated as this may cause agitation precipitating complete airway obstruction. Leukocytosis 20K generally present on CBC with left shift. Epiglottitis: Imaging Lateral neck film shows “thumb sign” Epiglottitis: Management 1) Airway Patient should be nasotracheally intubated in an OR setting with a team standing by who can perform tracheostomy. Usually patient remains intubated x 2-3 days. 2) Antibiotics: Oxacillin/Nafcillin(50mg/kg IV Q6) AND Ceftriaxone 50mg/kg IV QD x7-10 days. References Wald, E et al. Peritonsillar and Retropharyngeal Abscess in Children. 2008 Woods, C et al. Epiglottitis. 2008 Quintero, D et al. Assesment of