Rosen & Barkin's 5-Minute Emergency Medicine Consult (417 page)

• May be delayed for hours
  
• Blunt trauma recognition is most challenging
  
• Blood, cervical collar, or polytrauma may distract from subtle findings
  
• Neck tenderness
  
• Bruising or abrasions over the anterior neck
  
• Hoarseness or voice changes
  
• Hemoptysis
  
• Dysphonia
  
• Stridor
  
• SC or mediastinal emphysema
  
• Dyspnea
  
• Pneumothorax
  
• Loss of normal cartilaginous landmarks of neck
  
• Difficulty with mechanical ventilation
  

• Endoscopic evaluation should take precedence over radiography, as mucosal edema may contribute to airway compromise more than skeletal injury.
  
• Cervical spine imaging:
  
  • Plain radiographs are not very helpful and should not supplant cervical CT scan
    
• CXR:
  
  • Identify pneumothorax, SC emphysema, and pneumomediastinum
    
• CT scan (with IV contrast) of cervical spine with fine cuts of larynx:
  
  • Contrast may identify vascular injuries
    
  • Recommended unless the patient is going directly to surgery
    
  • Useful even in cases of apparently less severe symptoms and minor abnormalities on indirect laryngoscopy
    
• Pulse oximetry
  

Arterial blood gas potentially useful if the patient is having respiratory difficulty:

• Identifies hypoxia, hypercarbia
  

• Fiberoptic laryngoscopy:
  
  • Visualization of injuries involving the airway, vocal cords, ideally with a nasopharyngoscope
    
• Angiography:
  
  • Penetrating injuries
    
  • Only when concern exists for possible vascular injuries
    
• CT angiogram offers advantages to conventional angiography:
  
  • Readily accessible and less invasive
    
  • Can be rapidly performed
    
  • Few complications
    
  • Provides useful information on cervical soft tissues, aerodigestive tract, spinal canal, and spinal cord
    
• Fiberoptic bronchoscopy and esophagoscopy
  
• Surgery:
  
  • As indicated by severity of injury
    
  • Emergent surgical repair if necessary
    

Associated injuries:

• Intracranial injuries (13%)
  
• Open neck injuries (9%)
  
• Cervical spine injuries (8%)
  
• Esophageal injuries (3%)
  
• Carotid artery injury
  
• Phrenic nerve injury
  
• Hypoxic cerebral injury
  
• Airway edema
  
• Aspiration pneumonitis
  
• Air embolism
  

• The pediatric larynx is located higher in the neck and is more cartilaginous and mobile than in adults; thus, pediatric patients are more resistant to laryngeal fractures.
  
• Loosely attached submucosal tissue allows for greater soft-tissue trauma, massive edema, and hematoma formation:
  
  • With smaller airway diameter, airway compromise can occur rapidly.
    
• Symptoms can vary from neck tenderness or hoarseness to respiratory distress and stridor.
  
• CT imaging may not add much to the physical and fiberoptic exam of the child as fractures of the poorly mineralized larynx may not be visualized.
  

TREATMENT

• Cautions:
  
  • Aggressive airway management may be necessary: Oxygen, suctioning
    
  • Cervical spine immobilization
    
  • Injury may be overlooked if patient is intubated pre-hospital for other injuries owing to loss of subjective complaints.
    
• Controversies:
  
  • Elective intubation is not advocated.
    

Airway management is of primary concern:

• Severe injuries may require operative management.
  
• Early intubation to preclude progressive respiratory compromise.
  
• Formal tracheostomy under local anesthesia may be required rather than endotracheal intubation when more severe neck injury is present.
  
• Avoid
  repeated orotracheal intubation attempts:
  
  • Proceed to surgical airway.
    
• Cricothyrotomy for severe maxillofacial injuries and injuries cephalad to cricothyroid cartilage.
  
• Avoid
  cricothyrotomy if hematoma present over the cricothyroid membrane or there is evidence of cricotracheal disruption.
  
• Emergent tracheostomy may be the only option to secure an airway.
  

• Elective intubation is not recommended.
  
• Mandatory flexible fiberoptic laryngoscopy
  
• CT scan if management course is in doubt
  

• Supplemental humidified oxygen
  
• Elevate head of bed to decrease cerebral and neck soft tissue edema
  
• Maintain NPO status
  
• Voice rest as much as possible
  
• Obtain IV access
  
• Consult otolaryngologist for surgical evaluation
  
• Positive end-expiratory pressure and volume-controlled ventilation for severe pulmonary injury associated with acute respiratory distress syndrome or aspiration pneumonitis
  

• For laryngeal injury with SC emphysema:
  
  • Assume that the mucosa of the upper airway has communicated with the deep tissue of the neck:
    
    • Ampicillin/sulbactam: 1.5–3 g IV (peds: 50 mg/kg IV) q6h
      
    • Clindamycin: 600–900 mg IV q8h (peds: 25–40 mg/kg/24h IV)
      
    • Histamine-2 blockers to prevent irritation to mucosal injuries (e.g., ranitidine 150–300 mg IV; peds: 2–4 mg/kg/d div. q6h IV) or proton-pump inhibitors (e.g., pantoprazole 40 mg IV, no pediatric dosing)
      
• For laryngeal edema, steroids may be indicated:
  
  • Not routinely used, but may be used for massive edema.
    
  • Methylprednisolone 250 mg IV q4h (faster acting)
    
  • Dexamethasone 8–10 mg IV q8h (peds: 0.15–0.6 mg/kg/dose IV)
    

If stridor present, consider nebulized racemic epinephrine: 2.25% 0.25–0.5 mL in 2.5 mL NS.

FOLLOW-UP

• Patients with true laryngeal injuries must be admitted to a monitored setting for observation and airway management; prepare for emergent surgical repair of laryngeal defect.
  
• Patients with suspected laryngeal injury or highly suspicious mechanism must be admitted to a monitored setting for observation and serial flexible fiberoptic laryngoscopic exams.
  

Mandatory admission is recommended in all patients for oximetry, oxygen, and serial fiberoptic laryngoscopic exams.

Patients without evidence of serious laryngeal injury or airway edema or compromise after an appropriate period of observation in the ED (usually 6 hr):

• Patients can appear deceptively normal for several hours after injury; if there is any doubt, admit to a monitored setting.
  

• Bell RB, Verschueren DS, Dierks EJ. Management of laryngeal trauma.
  Oral Maxillofac Surg Clin North Am
  . 2008;20(3):415–430.
  
• Comer BT, Gal TJ. Recognition and management of the spectrum of acute laryngeal trauma.
  J Emerg Med
  . 2012;43(5):e289–e293.
  
• Gómez-Caro A, Ausín P, Moradiellos FJ, et al. Role of conservative medical management of tracheobronchial injuries.
  J Trauma
  . 2006;61(6):1426–1434.
  
• Pancholi SS, Robbin WK, Desai A, et al. Laryngeal fracture: Treatment.
  Emed Otololaryngol Facial Plastic Surg
  . Available at:
  http://emedicine.medscape.com/article/865277-treatment
  . Updated October 22, 2012.
  
• Shires CB, Preston T, Thompson J. Pediatric laryngeal trauma: A case series at a tertiary children’s hospital.
  Int J Pediatr Otorhinolaryngol
  . 2011;75(3):401–408.
  

CODES

• 807.5 Closed fracture of larynx and trachea
  
• 807.6 Open fracture of larynx and trachea
  

BASICS

• Lead has multiple mechanisms of toxicity:
  
  • Binds sulfhydryl groups and affects multiple enzymatic processes
    
  • Resembles Ca
    ²⁺
    thereby interfering with Ca
    ²⁺
    -
    dependent processes, such as cell signaling
    
  • May have mutagenic potential and play a role in human carcinogenesis
    
• Distribution:
  
  • Up to 99% of lead is bound to erythrocytes after initial absorption.
    
  • Ultimately redistributed into bone:
    
    • 95% of total body lead in adults
      
    • 70% of total body lead in children
      
  • High lead levels in the serum compromise the blood–brain barrier and result in lead entry into the CNS and neurotoxicity.
    
• Often coexists with iron deficiency; this allows for increased lead absorption in the gut.
  
• Impairs heme synthesis, leading to elevated free erythrocyte protoporphyrin (FEP); these complex with zinc, resulting in elevated zinc protoporphyrin (ZPP).
  
• Levels correlate poorly with symptoms:
  
  • Associated with drops in intelligence quotient (IQ) and increase in violent behavior