Pyogenic Infections of the Deep Neck Spaces: An Overview

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CASE: HPI
 BV. 14 year old F
 Remote tonsillectomy and ESS x 2
 In the ED with 9 d h/o sore throat and
odynophagia. Antecedent ‘head cold’ 4 d prior, has
since resolved with conservative measures.
 Developed intense L otalgia 2 d ago. Treated with
amoxicillin for putative AOM → no improvement.
 Last night, spiked fevers to 101. 5 F. Had emesis.
Not tolerating PO.
Courtesy of BCM Dept. OTO-HNS. Grand Rounds Archives. 16 Sept 2010
CASE: PHYSICAL
 VITALS:
 GEN:
 EARS:
 NOSE:
 MOUTH:
 NECK:
 PULM:
 NEURO:
T 102.5 | BP 138/66 | HR 116 | R 24 | SpO2 97% RA
Sitting comfortably. Phonation is normal. No drooling.
L pre-auricular tenderness. External ears normal. TMs
quiet bilaterally.
Normal nares, septum, and turbinates.
Mandible centered. Moderate trismus. Tonsils surgically
absent. Posterior pharynx with L > R fullness, no
erythema or exudates.
No meningismus. Mildly restricted active ROM to L.
Tenderness at Level II on L > R.
Respirations relaxed. No stridor. Lung fields clear
throughout.
Mental status is clear. No lateralizing deficits.
CASE: LABS and STUDIES
 CBC:
 BMP:
 Rapid Strep:
 AP Neck Film:
 CXR:
WBC 21,000 with 85% PMNs, 15% band forms
Na 149, K 5.1, Cr 1.4, BUN: 30
Non-reactive
Unremarkable
Unremarkable
Victor Tseng, MS-3
OTO-HNS Subrotation
DEFINITIONS
DEEP NECK SPACES: Eleven anatomic or
potential compartments created by interfascial
planes within the neck
DEEP NECK INFECTION: A supperative (usually
bacterial) infection within the deep neck spaces of
the deep cervical fascia
AXIAL ANATOMY
SAGITTAL ANATOMY
SAGITTAL ANATOMY
RADIOLOGIC ANATOMY
HEAD AND NECK AXIAL
MRI FLYTHROUGH (LINK)
A MENU OF SPACES: PEARLS
 SUPRAHYOID
 PARAPHARYNGEAL (PP): A major nexus of contiguous spread. Transmits the
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carotid sheath. Isolated involvement is uncommon.
SUBMANDIBULAR (SM): Infection may lead to upper airway obstruction
MASTICATOR: Most closely associated with trismus. Almost exclusively secondary
to odontogenic causes.
PAROTID: Most likely seen in dehydrated and decrepit patients with poor dentition
TEMPORAL: Between temporalis fascia and temporal bone periostium
PERITONSILLAR (PTS): Most common site overall, but not aknowledged as a true
DNI, since it is not defined by fascial apposition
 INFRAHYOID
 RETROPHARYNGEAL (RPA): Extends from skull base to level of carina (T2). Does
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not communicate with the pleural space.
DANGER: Infection easily escapes into the mediastinum and pleural space
PREVERTEBRAL (PV): Extends to coccyx and may develop into psoas absess.
CAROTID: Associated with IVDA and septic thromboembolism
PRETRACHEAL (PT): Associated with anterior perforation of the esophageal wall
HOOFBEATS: COMMONS
 PERITONSILLAR (49%)
 RETROPHARYNGEAL (22%, 43% non-PTS)
 Most common DNI across all age groups
 But it is predominantly a pediatric infection
 SUBMANDIBULAR (14%, 27% non-PTS)
 PAROTID (11%)
RETROPHARYNGEAL ABSCESS (RPA)
 EPIDEMIOLOGY
 > 75% of cases occur < 6 years old. 50% of cases occur by 12 mos.
 Overall (treated) mortality approximately 1%
 ETIOLOGY
 Children (< 18 years): 60% related to supperative LAD due to URI, AOM,
acute sinusitis
 Adults: Mostly due to trauma, foreign body, instrumentation, or contiguous
extension from primary DNI
 MICROBIOLOGY
 >90% are polymicrobial. Average n = 5 microbes isolated from culture.
 >50% of isolates grow anerobes
 S. pyogenes > S. aureus > oropharyngeal anaerobes > H. influenzae
 PATHOPHYSIOLOGY
 supperative lymphadenitis → organized phlegmon → mature abscess
 Morbidty and mortality is due to development of complications
RETROPHARYNGEAL ABSCESS (RPA)
 CLINICAL PRESENTATION
 Adults: Sore Throat > Fever > Dysphagia > Odynophagia > Nuchal Pain >
Dyspnea > Hoarseness
 Children: Sore Throa (84%) > Fever (64%) > Odynophagia (55%) > Cough
 Infants: Neck Fullness (97%) > Fever (85%) > Poor PO (55%)
 DIFFERENTIAL DIAGNOSIS
 Epiglottitis, PTA, Croup, Diphtheria
 Angioedema
 Respiratory lymphagiomas or hemangiomas
 Traumatic esophagus or airway, foreign body impaction
 COMPLICATIONS
 Acute Mediastinitis: very high (>50%) mortality
 Empyema
 Pericardial effusion with tamponade physiology
 Mass effect: supraglottic airway obstruction (anterior) or epidural abscess
(posterior)
RETROPHARYNGEAL ABSCESS (RPA)
 PHYSICAL FINDINGS
 Adults: pharyngeal edema > cervical LAD > nuchal rigidity > drooling > stridor
 Children: fever and nuchal rigidity (64%) > retropharyngeal bulge and neck
mass (55%) > agitation or lethargy > drooling (22%) > respiratory distress or
stridor
 Other: dystonic reactions (torticollis), dysphonia (‘hot potato’ voice), trismus
 In a drooling or stridorous patient, be minimally invasive when examining the
pharynx
 LABORATORY
 CBC: 20% of cases may not show leukocytosis or relative left shift
 Standard GAS rapid throat swab and culture
 Blood cultures: rarely return positive growth
 Wound culture: 91% sensitivity for polymicrobial infection
 CRP and ESR to follow baseline. CRP is actually prognostic of hospitalization
legnth.
 Pre-operative labs in anticipation of surgical intervention (coagulation panel,
metabolic panel, type and cross)
RETROPHARYNGEAL ABSCESS (RPA)
 IMAGING
 Lateral Neck Film: look for widened AP diameter of retropharyngeal tissue.
Maximal reported sensitivity of 88%.
 CT Neck with Contrast
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Most important imaging test to consider
Hypodense lesion of retropharyngeal space with rim enhancement
Absolute Indications: equivocal LNF, negative LNF with high clinical suspicion
Sensitivity 77 – 100% , Specificity 95%
 High-Resolution U/S
 Maybe used to track abscess during hospitalization. Some anatomic insight into
surrounding vascular structures.
 Proof of concept. No data to support routine use.
 MRI: Not recommended for initial evaluation due to untimeliness
 Flexible Endoscopy: not recommended
RETROPHARYNGEAL ABSCESS (RPA)
RETROPHARYNGEAL ABSCESS (RPA)
 MEDICAL MANAGEMENT
PARENTERAL ANTIBIOTIC THERAPY is guided by suspected source of infection!
SUSPECTED SOURCE
Odontogenic
FIRST-LINE THERAPY
ALTERNATIVE
Ampicillin-Sulbactam 3 g IV q6h
Imipenem 500 mg IV q6h
Penicillin G 2-4 MU IV q4-6h +
Metronidazole 500 mg IV q6-8h
Meropenem 1 g IV q8h
Clindamycin 600 mg IV q6-8h
Rhinogenic and Otogenic
Ampicillin-sulbactam 3 g IV q6h
As above
Ceftriaxone 1 g IV q24h +
Metronidazole 500 mg IV q6-8h
Ciprofloxacin 400 mg q12h +
Clindamycin 600 mg IV q6-8h
Immuncompromised
Cefipime 2 g IV q12h +
Metronidazoole 500 g IV q6h
As above
Piperacillin-Tazobactam 4.5 g IV q6h
 Must have MRSA coverage if strain is endemic, poor clinical response to
clindamycin, or in patients with very severe disease
RETROPHARYNGEAL ABSCESS (RPA)
 SURGICAL INDICATIONS
Important: > 50% of patients with uncomplicated RPA achieve
spontaneous resolution with medical therapy alone
 Respiratory distress
 Urgent complication of RPA (e.g. mediastinitis, empeyema, septic
thrombophlebitis)
 Diameter of abscess > 2 cm on CT Neck
 No response to ABx therapy at 48 hrs
 SURGICAL APPROACH
 U/S guided FNA: preferred in hemodynamically unstable patients, or those
with small and accessible loculations
 I/D: Usually requires trans-cervical entry. Small abscesses may be drained
via trans-oral aspiration.
QUESTIONS
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