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 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 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 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