Page 587 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

CHAPTER 47: Upper Airway Obstruction 407

Peritonsillar abscesses are located between the tonsil and the supe- or anesthesiologist. Visualization of a swollen, cherry-red epiglottis con-
rior constrictor muscle of the pharynx. Affected patients are typically firms the diagnosis. This examination is preferentially performed in the
young adults and have a history of prior tonsillitis; not surprisingly, operating room, or at a minimum with all necessary airway personnel
Streptococcus species are most commonly isolated, frequently along and equipment available. Although many adults with epiglottitis may be
with other oral organisms. Presenting symptoms include sore throat, managed with antibiotics and observation in the ICU, the potential for
13
trismus, and voice change. Physical signs include trismus, uvular devia- acute airway obstruction should always be considered to be extremely
tion, and inferior displacement of the superior pole of the tonsil on the high. 14,15 A tracheostomy tray should be at the bedside, and all relevant
affected side. Despite the prevalence of this disorder, there are several airway personnel—anesthesia as well as otolaryngology—should be
11
aspects of management that remain controversial. While steroids are alerted to the patient’s condition and location. At no time should the
12
occasionally administered to patients with peritonsillar abscess, there patient be sent unaccompanied to another location in the hospital.
are no good studies to support or refute their efficacy. Contemporary While blood cultures may on occasion reveal the etiology, in most
surgical approaches tend to favor needle aspiration and incision and cases the specific organism is not identified, and antibiotic treatment is
drainage over immediate tonsillectomy. Complications of this disease empirical. The response to treatment is typically prompt.
include UAO and, rarely, thrombophlebitis of the internal jugular vein, Infections of the larynx may be caused by viruses, bacteria, or fungi.
a condition known as Lemierre syndrome. This condition is usually Laryngotracheitis in children (croup) is usually caused by a viral
associated with Fusobacterium necrophorum, but other oral flora may infection, and UAO may result. While viral infections of the larynx
be responsible. Bacteremia and septic emboli may result. The role of are rarely serious in adults, bacterial laryngotracheitis can be life-
anticoagulation in Lemierre syndrome is controversial. threatening. Because the causative organisms include Staphylococcus
Occasionally, tonsillar enlargement from infectious mononucleosis aureus, Streptococcus pneumoniae, and Haemophilus influenzae, pneu-
may be so significant as to obstruct the airway. Management consists of monia may be present as well. Corynebacterium diphtheriae should be
close observation of the airway in a monitored setting, and the admin- considered in the differential diagnosis despite the infrequency with
istration of corticosteroids. which it is currently encountered in the United States. In particular,
Other Causes: Angioedema from a variety of causes can involve the nonimmunized persons and those individuals returning from countries
tongue and hypopharynx and threaten airway patency both above and at with high rates of infection are at risk. Diphtheria commonly presents
the level of the larynx. This disorder is discussed below along with other initially as tonsillitis and pharyngitis. Subsequent spread inferiorly may
disorders of the larynx. Stevens-Johnson syndrome and toxic epidermal cause laryngitis, although occasionally the larynx is the only site of
necrolysis are rare vesiculobullous diseases that involve the skin and involvement. Clinical manifestations include fever, sore throat, malaise,
mucous membranes. Affected patients may develop bullae and edema headache, and vomiting. Physical examination may reveal a tenacious
of the upper airway mucosa, leading to obstruction. Causes typically gray or black membrane overlying involved sites, and cervical lymph-
include medications (with antibiotics, nonsteroidal anti-inflammatory adenopathy may be present. Delays in treatment increase the likelihood
medications, and anticonvulsants frequently being implicated), infec- of systemic complications from circulating toxin, such as myocarditis,
tions, and malignancies. Depending on their location, facial fractures neuritis, and nephritis. Death occurs in 5% to 10% of cases, either from
may lead to UAO through local swelling and a loss of support for the systemic effects of diphtheria toxin or from UAO, the latter occurring
tongue and/or facial skeleton. Cancers of the head and neck are impor- more commonly in infants. Treatment includes antibiotics and equine
tant causes of upper airway obstruction and may present with associated antitoxin, which can be obtained through the Centers for Disease
infections, potentially obscuring the diagnosis. While oral neoplasms Control and Prevention. Sensitivity to horse serum should be assessed
are common, patients typically, although not invariably, present for prior to administration of the antitoxin, and desensitization should be
evaluation before the airway can be compromised. Obstructive sleep performed as necessary. Because infection does not ensure immunity,
apnea is a form of chronic UAO that is exhibited only during sleep, and immunization is indicated after recovery.
Fungal laryngotracheitis may be caused by Candida albicans, histo-
is considered in greater detail in Chap. 130. plasmosis, blastomycosis, and coccidioidomycosis. In addition to fever
■ LARYNGEAL CAUSES and sore throat, affected patients may develop dyspnea and voice change
Infectious Causes: Supraglottitis, or infection of the supraglottic por- from vocal cord nodules and/or vocal cord fixation. The diagnostic
tion of the larynx, may cause life-threatening UAO primarily through approach depends on the presentation, as other sites of involvement—
for example, pulmonary infiltrates—may be present. Respiratory pap-
involvement of the epiglottis. Vaccination against Haemophilus influ-
enzae has successfully decreased the number of cases of epiglottitis in illomatosis is caused by human papillomavirus types 6 and 11, and
is manifested by multiple—sometimes innumerable—papules in the
children caused by this organism. As a result, adults comprise a greater
proportion of all cases of epiglottitis. In addition to H influenzae, larynx and trachea.
Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus parain- Iatrogenic and Traumatic Causes
fluenzae, group A streptococci, viruses, anaerobes, and fungi all have Related to Endotracheal Intubation A variety of upper airway problems can
been implicated as causes of epiglottitis. Because many physicians who follow endotracheal intubation and are listed in Table 47-1. Several of
treat adults will work a lifetime without seeing a single patient with the these problems merit further discussion here. Laryngospasm consists
acute onset of sore throat go on to develop UAO, the diagnosis may be of uncontrolled glottic closure, and respiratory distress with inability
missed. The classic presentation is that of a patient sitting upright and to ventilate the patient may result. It can be provoked by a variety of
leaning forward, drooling; however, these signs may not be present stimuli, including stimulation of the glottic aperture and/or superior
initially. An additional clue is the rapid onset and severity of odyno- laryngeal nerve during intubation, medications including general anes-
phagia. Many, but not all, patients have a muffled or “hot potato” voice, thetics and opioids, and the presence of secretions or blood in the upper
and signs of toxicity, such as fever and tachycardia, may be present. airway. Careful suctioning of the mouth and endotracheal tube prior to
Otolaryngology and anesthesiology consultation should be obtained if extubation may reduce the likelihood of laryngospasm after extubation,
the diagnosis is suspected, while an oral examination should be per- in addition to improving pulmonary toilet. When laryngospasm occurs,
formed extremely carefully, if at all. The approach to diagnosis depends mask ventilation with 100% oxygen should be performed along with jaw
on the patient’s overall clinical status. While lateral films of the neck may thrust and chin lift. If the laryngospasm fails to break and ventilation is
reveal the diagnosis, a negative examination does not exclude epiglot- not possible, the short-acting paralytic succinylcholine may be adminis-
titis. A fiberoptic examination can often be performed carefully via the tered followed by mask ventilation or endotracheal intubation. It should
nasopharyngeal route, but should be performed only by a person expe- be emphasized that in the ICU, laryngeal edema is a much more likely
rienced in treating this problem, preferably a seasoned otolaryngologist cause of postextubation stridor than laryngospasm.

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