Page 952 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

CHAPTER 73: Life-Threatening Infections of the Head, Neck, and Upper Respiratory Tract 683

is usually heralded by several minor bleeds before a major hemorrhage (eg, from chicken bones or following instrumentation); in such cases, the
occurs and signals the need for urgent surgical intervention. Such bleed- presence of a sore throat or difficulty in swallowing or breathing may be
ing may involve the oral cavity, nose, or ear or appear as ecchymosis in the first indications of infection. More distant sources include odonto-
the neck and surrounding tissues. An ipsilateral Horner syndrome, and genic sepsis and peritonsillar abscess (now a rare cause). Infection from
otherwise unexplained ninth to twelfth cranial nerve palsies, is an addi- these sources may often obscure the diagnosis because of associated
tional premonitory syndrome of carotid sheath involvement. trismus, which makes direct examination of the posterior pharyngeal
Treatment of lateral pharyngeal space infection initially depends on wall difficult. In this setting, CT and radiographic views of the lateral
whether local suppuration is present, but often this is difficult to deter- neck are especially helpful and may demonstrate cervical lordosis with
mine. CT, careful needle aspiration, or more-definitive incision and swelling and gas collections in the retropharyngeal space, causing ante-
drainage may be required. Most cases of postanginal sepsis with sup- rior displacement of the larynx and trachea (Fig. 73-10). Radiographs
purative jugular thrombophlebitis can be managed medically without may also help differentiate this infection from prevertebral space sepsis
the need for ligation or surgical resection of the infected vein. Prolonged arising from cervical osteomyelitis. Once a diagnosis is made, surgical
courses of intravenous antibiotics (3-6 weeks) will be required. Since exploration and wide drainage should be carried out without delay.
anaerobic bacteremia caused by Bacteroides species or Fusobacterium Acute necrotizing mediastinitis is the most feared complication of ret-
necrophorum is frequently present, and penicillin resistance among ropharyngeal space infections. 15,16 The onset is rapid and is characterized
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these organisms is increasingly recognized, therapy generally requires by the following: (a) widespread necrotizing process extending the length
addition of metronidazole, clindamycin, β-lactamase–stable cephalo- of the posterior mediastinum and occasionally into the retroperitoneal
sporins, or a carbapenem. Fever may be slow to resolve, even in cases space, (b) rupture of mediastinal abscess into the pleural cavity with
successfully treated, particularly if there is metastatic involvement. empyema or development of loculations, and (c) pleural or pericardial
Anticoagulants have sometimes been used in this setting, but their effusions, frequently with tamponade. Aspiration pneumonia is also a
efficacy is unconfirmed. Surgical ligation of the internal jugular vein, significant problem (50% of cases) and may be secondary to impairment
the only available therapeutic option in the pre-antibiotic era, is now of swallowing or spontaneous rupture of the abscess into the airway.
required only in the rare patient who fails to respond to antibiotic As might be expected, the mortality in adults is high (25%), even when
therapy alone. When there is impending or frank rupture of the carotid appropriate antibiotics are administered. Early diagnosis and timely
artery, the artery must be ligated immediately, with special attention debridement are the mainstays of successful treatment. Mediastinal
given to the airway and to restoration of blood volume. Predictably, drainage may be attained by either the cervicomediastinal or transtho-
morbidity (eg, stroke) and mortality are high (20%-40%). In all such racic approach. Although the cervical approach may be effective in early
cases, early surgical intervention is the key to a successful outcome. mediastinitis, thoracotomy is generally indicated once the necrotizing
Infections of the Retropharyngeal, “Danger,” and Prevertebral Spaces: The process has entered the danger space. In patients who are recovering, it
retropharyngeal, “danger,” and prevertebral spaces all lie between the is important to restrict all oral intake until the swallowing impairment,
deep cervical fascia surrounding the pharynx and esophagus anteri- which may have a prolonged course, has resolved completely.
orly and the vertebral spine posteriorly (Fig. 73-1). The retropharyn- ■ SUPPURATIVE PAROTITIS
geal space is bound anteriorly by the constrictor muscles of the neck
and their fascia, and posteriorly by the alar layer of the deep cervical Acute bacterial parotitis primarily affects the elderly, malnourished,
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fascia, extending from the base of the skull to the level of the superior dehydrated, or postoperative patient. Ductal (Stensen) obstruction
mediastinum, where the two fascial layers fuse. The “danger” space secondary to sialolithiasis appears to be a major predisposing condi-
is interposed between the retropharyngeal space anteriorly and the tion. Other antecedent factors include sialogogic drugs and trauma.
prevertebral space posteriorly. It extends from the base of the skull Clinically, there is sudden onset of firm, erythematous swelling of the
and descends freely through the entire posterior mediastinum to the pre- and postauricular areas extending to the angle of the mandible. This
diaphragm. The prevertebral space is bound anteriorly by the alar is associated with exquisite local pain and tenderness but not trismus.
fascia, and posteriorly by the prevertebral fascia, which originates Systemic findings of high fevers, chills, and marked toxicity are gener-
on the spinous processes and encircles the splenius, erector spinae, ally present. Contiguous spread may lead to osteomyelitis of the adjacent
and semispinalis muscles. Before completing its circle anterior to the facial bones. S aureus has been the predominant causative organism.
vertebral bodies, it fuses to the transverse processes. The prevertebral Early surgical drainage and decompression of the gland are generally
space extends from the base of the skull to the coccyx, thus allowing required, since spontaneous drainage is uncommon. Because of its close
infectious spread as far down as the psoas muscle sheath. relationship with the posterior aspect of the lateral pharyngeal space,
Retropharyngeal abscesses are among the most serious of deep space progression of infection into the parotid space may lead to massive
infections, since infection can extend directly into the superior mediasti- swelling of the neck with respiratory obstruction and has the added
num, or the entire length of the posterior mediastinum via the “danger” potential risk of direct extension into the “danger” and retropharyngeal
space (Fig. 73-1). spaces and hence to the posterior mediastinum (Fig. 73-1).
young children, infection usually reaches this space via lymphatic chan- ■ PERITONSILLAR ABSCESS
Retropharyngeal infections may occur in both children and adults. In
nels, most commonly as complications of suppurative adenitis following This condition, also known as quinsy, is a suppurative complication of
an upper respiratory tract infection. The onset may be insidious, with acute tonsillitis involving the peritonsillar space. The latter consists of
little more than fever, irritability, drooling, or possibly nuchal rigidity. loose areolar tissue overlying the tonsil surrounded by the superior pha-
More acute symptoms include dysphagia and dyspnea. The latter may be ryngeal constrictor muscle and the anterior and posterior tonsillar pillars
due either to a local mass effect or to laryngeal edema. Generally there is (Fig. 73-6). Peritonsillar abscesses may affect patients of all ages but
little pain, but the neck may be held rigidly and tilted to the unaffected are most common among young adults between the ages of 15 and
side. Definite bulging of the posterior pharyngeal wall is usually seen 30 years. The patient appears ill, with fever, sore throat, dysphagia, tris-
but may need careful palpation to be appreciated. The main dangers mus, pooling of saliva, and a muffled voice. The abscess is usually unilat-
are severe laryngeal edema with airway obstruction and abscess rupture eral, with associated cervical lymphadenitis. Examination of the pharynx
with consequent aspiration pneumonia or asphyxia. Many cases will in the majority of cases reveals swelling of the anterior pillar and the
respond to antibiotic therapy alone if treatment precedes the develop- soft palate and, less commonly, the middle portion or lower pole of the
ment of frank suppuration. tonsil. Initially, needle drainage in the Trendelenburg position should be
In adults, infection may reach the retropharyngeal space from either attempted, and the patient should be monitored closely and managed
local or distant sites. The former usually results from penetrating trauma with intravenous antibiotics alone. Failure to obtain pus is an indication

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