2 Courtesy of BCM Dept. OTO-HNS. Grand Rounds Archives. 16 Sept 2010 CASE: HPIBV. 14 year old FRemote tonsillectomy and ESS x 2In 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 F. Had emesis. Not tolerating PO.Courtesy of BCM Dept. OTO-HNS. Grand Rounds Archives. 16 Sept 2010
3 CASE: PHYSICALVITALS: T | BP 138/66 | HR 116 | R 24 | SpO2 97% RAGEN: Sitting comfortably. Phonation is normal. No drooling.EARS: L pre-auricular tenderness. External ears normal. TMs quiet bilaterally.NOSE: Normal nares, septum, and turbinates.MOUTH: Mandible centered. Moderate trismus. Tonsils surgically absent. Posterior pharynx with L > R fullness, no erythema or exudates.NECK: No meningismus. Mildly restricted active ROM to L. Tenderness at Level II on L > R.PULM: Respirations relaxed. No stridor. Lung fields clear throughout.NEURO: Mental status is clear. No lateralizing deficits.
4 CASE: LABS and STUDIES CBC: WBC 21,000 with 85% PMNs, 15% band forms BMP: Na 149, K 5.1, Cr 1.4, BUN: 30Rapid Strep: Non-reactiveAP Neck Film: UnremarkableCXR: Unremarkable
5 Common Infections of the Deep Neck Spaces: An Overview Victor Tseng, MS-3OTO-HNS Subrotation
6 DEFINITIONSDEEP NECK SPACES: Eleven anatomic or potential compartments created by interfascial planes within the neckDEEP NECK INFECTION: A supperative (usually bacterial) infection within the deep neck spaces of the deep cervical fascia
10 HEAD AND NECK AXIAL MRI FLYTHROUGH (LINK) RADIOLOGIC ANATOMYHEAD AND NECK AXIAL MRI FLYTHROUGH (LINK)
11 A MENU OF SPACES: PEARLS SUPRAHYOIDPARAPHARYNGEAL (PP): A major nexus of contiguous spread. Transmits the carotid sheath. Isolated involvement is uncommon.SUBMANDIBULAR (SM): Infection may lead to upper airway obstructionMASTICATOR: Most closely associated with trismus. Almost exclusively secondary to odontogenic causes.PAROTID: Most likely seen in dehydrated and decrepit patients with poor dentitionTEMPORAL: Between temporalis fascia and temporal bone periostiumPERITONSILLAR (PTS): Most common site overall, but not aknowledged as a true DNI, since it is not defined by fascial appositionINFRAHYOIDRETROPHARYNGEAL (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 spacePREVERTEBRAL (PV): Extends to coccyx and may develop into psoas absess.CAROTID: Associated with IVDA and septic thromboembolismPRETRACHEAL (PT): Associated with anterior perforation of the esophageal wall
12 HOOFBEATS: COMMONS PERITONSILLAR (49%) RETROPHARYNGEAL (22%, 43% non-PTS)Most common DNI across all age groupsBut it is predominantly a pediatric infectionSUBMANDIBULAR (14%, 27% non-PTS)PAROTID (11%)
13 RETROPHARYNGEAL ABSCESS (RPA) EPIDEMIOLOGY> 75% of cases occur < 6 years old. 50% of cases occur by 12 mos.Overall (treated) mortality approximately 1%ETIOLOGYChildren (< 18 years): 60% related to supperative LAD due to URI, AOM, acute sinusitisAdults: Mostly due to trauma, foreign body, instrumentation, or contiguous extension from primary DNIMICROBIOLOGY>90% are polymicrobial. Average n = 5 microbes isolated from culture.>50% of isolates grow anerobesS. pyogenes > S. aureus > oropharyngeal anaerobes > H. influenzaePATHOPHYSIOLOGYsupperative lymphadenitis → organized phlegmon → mature abscessMorbidty and mortality is due to development of complications
14 RETROPHARYNGEAL ABSCESS (RPA) CLINICAL PRESENTATIONAdults: Sore Throat > Fever > Dysphagia > Odynophagia > Nuchal Pain > Dyspnea > HoarsenessChildren: Sore Throa (84%) > Fever (64%) > Odynophagia (55%) > CoughInfants: Neck Fullness (97%) > Fever (85%) > Poor PO (55%)DIFFERENTIAL DIAGNOSISEpiglottitis, PTA, Croup, DiphtheriaAngioedemaRespiratory lymphagiomas or hemangiomasTraumatic esophagus or airway, foreign body impactionCOMPLICATIONSAcute Mediastinitis: very high (>50%) mortalityEmpyemaPericardial effusion with tamponade physiologyMass effect: supraglottic airway obstruction (anterior) or epidural abscess (posterior)
15 RETROPHARYNGEAL ABSCESS (RPA) PHYSICAL FINDINGSAdults: pharyngeal edema > cervical LAD > nuchal rigidity > drooling > stridorChildren: fever and nuchal rigidity (64%) > retropharyngeal bulge and neck mass (55%) > agitation or lethargy > drooling (22%) > respiratory distress or stridorOther: dystonic reactions (torticollis), dysphonia (‘hot potato’ voice), trismusIn a drooling or stridorous patient, be minimally invasive when examining the pharynxLABORATORYCBC: 20% of cases may not show leukocytosis or relative left shiftStandard GAS rapid throat swab and cultureBlood cultures: rarely return positive growthWound culture: 91% sensitivity for polymicrobial infectionCRP 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)
16 RETROPHARYNGEAL ABSCESS (RPA) IMAGINGLateral Neck Film: look for widened AP diameter of retropharyngeal tissue. Maximal reported sensitivity of 88%.CT Neck with ContrastMost important imaging test to considerHypodense lesion of retropharyngeal space with rim enhancementAbsolute Indications: equivocal LNF, negative LNF with high clinical suspicionSensitivity 77 – 100% , Specificity 95%High-Resolution U/SMaybe 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 untimelinessFlexible Endoscopy: not recommended
18 RETROPHARYNGEAL ABSCESS (RPA) MEDICAL MANAGEMENTPARENTERAL ANTIBIOTIC THERAPY is guided by suspected source of infection!Must have MRSA coverage if strain is endemic, poor clinical response to clindamycin, or in patients with very severe diseaseSUSPECTED SOURCEFIRST-LINE THERAPYALTERNATIVEOdontogenicAmpicillin-Sulbactam 3 g IV q6hPenicillin G 2-4 MU IV q4-6h + Metronidazole 500 mg IV q6-8hClindamycin 600 mg IV q6-8hImipenem 500 mg IV q6hMeropenem 1 g IV q8hRhinogenic and OtogenicAmpicillin-sulbactam 3 g IV q6hCeftriaxone 1 g IV q24h +Metronidazole 500 mg IV q6-8hCiprofloxacin 400 mg q12h + Clindamycin 600 mg IV q6-8hAs aboveImmuncompromisedCefipime 2 g IV q12h + Metronidazoole 500 g IV q6hPiperacillin-Tazobactam 4.5 g IV q6h
19 RETROPHARYNGEAL ABSCESS (RPA) SURGICAL INDICATIONSImportant: > 50% of patients with uncomplicated RPA achievespontaneous resolution with medical therapy aloneRespiratory distressUrgent complication of RPA (e.g. mediastinitis, empeyema, septic thrombophlebitis)Diameter of abscess > 2 cm on CT NeckNo response to ABx therapy at 48 hrsSURGICAL APPROACHU/S guided FNA: preferred in hemodynamically unstable patients, or those with small and accessible loculationsI/D: Usually requires trans-cervical entry. Small abscesses may be drained via trans-oral aspiration.