Deep Space Infections of the Neck: Considerations in Diagnosis and Management
Despite the decreased incidence of deep space neck infections since the advent of antibiotics, preventive healthcare, and improved hygiene, this condition still carries a high rate of complications and morbidity.
Complications
Even in the modern antibiotic era, life-threatening complications, namely, airway compromise, jugular vein thrombosis, mediastinal involvement, pneumonia, septic shock, and intracranial extensions may develop due to delays in diagnosis and treatment.7,10 Rare reports of cavernous sinus thrombosis have even been described.23 Abscesses left untreated can rupture spontaneously into the pharynx, leading to aspiration.15 In one study of 20 patients with descending necrotizing mediastinitis (DNM) as a severe complication of odontogenic infections, 30.4% of patients died as a result of septic shock and multiorgan failure.24 Descending necrotizing mediastinitis is associated with chest pain, dyspnea, fever, and significant toxemia. When DNM is suspected, CT imaging should be continued inferiorly into the chest, and a thoracic surgeon should be consulted.
Predictors of complications include patients older than age 65 years (OR, 6.12; 95% CI, 1.63-22.89), diabetes mellitus (OR, 9.0; 95% CI, 2.08-38.95), other comorbidities (OR, 5.44; 95% CI, 1.72-17.17), multiple space involvement (OR, 10.80; 95% CI, 2.59-44.97), and anterior visceral space involvement (larynx, thyroid, trachea, cervical esophagus) (OR, 26.80; 95% CI, 5.95-120.76).20 The size, shape, and dimensions of the anterior visceral space plays a key role in determining airway obstruction as well as the spread of infection to the anterior mediastinum.20
,Treatment and Management
Deep neck infections are treated with airway control, IV antibiotics, and, if necessary, surgical drainage.20 Although surgical drainage has been the mainstay of treatment for decades, newer studies suggest that patients who have abscesses less than 3.0 cm, are in stable clinical condition, and lack “danger” space involvement, may do well with antimicrobial therapy alone. Patients tolerating this approach tend to have shorter hospital stays with decreases in overall cost of treatment. However, prompt consultation for diagnosed or presumed deep space neck infection is key. In one study, more than 90% of the patients required surgical intervention. Without rapid medical/surgical intervention, patients tend to progress to critical status.3 Thus, the general consensus is for admission to a tertiary care center under the supervision of the head and neck surgical team.
Antibiotic Therapy
Due to the predictable makeup of the majority of polymicrobial neck infections, most patients can be treated empirically with antibiotic regimens that include clindamycin and β lactams alone or in combination with metronidazole. In odontogenic infections, nearly 20% of isolated species were penicillin resistant5; only 4% were resistant to clindamycin.8 Empiric antibiotic coverage must consider aerobic and anaerobic pathogens that synthesize β lactamase.3 Second- or third-generation cephalosporins such as cefoxitin or ceftriaxone, also are effective. Alternatively, a penicillin and β-lactamase inhibitor combination such as ampicillin-sulbactam provides appropriate coverage of predicted flora. De-escalation of antibiotic regimen is typical following return of culture and sensitivity testing.
Other Medical Therapy
Additional medical management should include initiation of IV fluid resuscitation. Until patients have demonstrated stability with positive clinical trajectory, the possibility of impending airway compromise should be considered and patients should be placed on a “nothing by mouth” status.
The debate is ongoing over use of corticosteroids, with controversy stemming from the anti-inflammatory and immunosuppressant effects of this intervention. Consensus recommendations are for dexamethasone 10 mg as an initial dose with 4 mg every 6 hours for 48 hours to aid in decreasing edema and chemical decompression with a goal of airway protection and improved antibiotic tissue penetration.24
Airway Management
Airway compromise can progress rapidly and is the most immediate, life-threatening complications encountered in the management of deep space neck infections. Direct compression of the airway may result from either displacement of the tongue posteriorly or secondary to laryngeal edema. Patients should be presumed to have a difficult airway and present challenges even when in a relatively controlled operating-room environment. In several studies, up to 75% of patients with Ludwig’s angina required tracheostomy. In a study reviewing 20 attempts at oral intubation, 11 were unsuccessful with failed airways requiring emergent tracheostomy. In one of the few prospective studies, airway management was accomplished by endotracheal intubation in over 90% of patients aided by a near equal number of fiberoptic and laryngoscopic approaches.5
There are multiple options for airway management, including close clinical observation, endotracheal intubation (fiberoptic or direct), and surgery. There is a lack of data in the literature to help determine the best method.25 A decision to observe the airway, perform intubation, or obtain tracheostomy must be made on an individual basis, considering the advantages and disadvantages of each.4,20
Observation. If initial evaluation reveals no impending airway compromise, close observation of the airway in an ICU setting is appropriate. The main complications of observation without mechanical intervention are unrecognized impending airway loss, risk of over sedation and loss of airway, or extension of infection and edema leading to asphyxiation. The benefit is that there is no mechanical intervention, which carries inherent risks.
