Goal: Look for sources that require surgery in patients that present with severe infections.

Transcription

1 High Risk EM Sukhjit Takhar, MD Assistant Clinical Professor of Emergency Medicine Faculty, Division of Infectious Disease UCSF-Fresno Goal: Look for sources that require surgery in patients that present with severe infections. Source Control: Draining infected fluid collection Debridement of infected solid tissue and removing foreign bodies Correct anatomic derangement We will focus on four diseases that require emergent surgical intervention Necrotizing soft tissue infections (necrotizing fasciitis) A necrotizing soft tissue infection is a soft tissue infection with necrotic changes on pathology. A diverse group of diseases. Can involve: Dermis, subcutaneous tissue, fascia, muscle Many names have been used depending on the organism and location. It is more important to understand that these infections are all soft tissue infections with necrotic changes and they require immediate surgical treatment. Patients often have co-morbid conditions. The diagnosis and treatment is in the operating room. Clinical Signs of soft tissue infection with systemic toxicity Severe pain (out of proportion to exam) Hard Signs (Easy to make the diagnosis now but, a little late) Bullae, crepitus, gas on xrays, hypotension, skin necrosis Diagnosis Obvious cases go straight to the operating room Diagnosis of early necrotizing infection can be difficult Radiographs are often used. Remember that soft tissue gas is not seen with Streptococcus pyogenes. CT and MRI can visualize facial planes. Patients are often too sick to get these studies. Gas rules in disease. Preliminary data on using a laboratory risk score looks promising (LRINEC score). Consider using it; especially if your surgeons like it. A score of 6 or greater increases the risk of NSTI. Pathogenesis ) Infection ) Inflammation 3) Endothelial disruption 4) Tissue hypoxia Involve your surgeons early if you are in doubt. Call them when you start thinking about calculating a LRINEC score. Early diagnosis is

2 High Risk EM difficult and experience with the disease is very important. Consider a necrotizing infection in your sick cellulitis cases; remember cellulitis does not cause septic shock. Early and aggressive surgical intervention Decreased bacterial inoculum Decreaed inflammatory response Improved survival Broad Spectrum Antibiotics Life threatening infection: Must cover MRSA, group A strep, and enteric gram negatives Vancomycin + Piperacillin/Tazobactam + Clindamycin Supportive care Laboratory risk indicator for necrotizing fasciitis Severe kidney infections The majority of urinary tract infections are uncomplicated and respond well to short courses of empiric antibiotics. Occasionally, patients present or rapidly develop sepsis or septic shock. It is imperative for the ED physician to perform an appropriate work up which includes imaging and early urologic consultation. An infected obstructed stone ( pus under pressure ) can rapidly kill a young-healthy patient. Pyelonephritis is usually diagnosed by clinical and lab findings (fever, flank pain, and pyuria). It responds quickly to antibiotics (48-7 hours). Most patients do not require imaging or specialty care. Image patients (ultrasound or CT) that present with sepsis or do not improve after 48 hours of appropriate therapy. Consider imaging patients that are sick enough to require admission for pyelonephritis. What am I looking for on imaging? Obstruction Abscess Necrotizing infections Value C-reactive protein <5 5 WBC count <5 5-5 >5 Hemoglobin > < Sodium 35 <35 Creatinine.6 >.6 Glucose 8 >8 LRINEC score 4 We are imaging patients to look for complications that require an intervention. The obstruction must be relieved, the abscess drained, and the necrotizing infection debrided. Necrotizing infections (emphysematous pyelonephritis) typically occur in the setting of obstruction and the patients are often diabetic. Occasionally a nephrectomy is life saving. RX Antibiotics Cover enteric gram negative organism (Quinolone, 3 rd /4 th generation cephalosporin, pip/ tazo, aminoglycoside, etc ) Hemodynamic resuscitation Fluids, Pressors Surgical drainage Percutaneous drainage, nephrectomy

3 High Risk EM Epidural abscess An epidural abscess is a collection of pus in between the dura and bone (vertebral column in spinal epidural abscess). The disease is uncommon (. cases/, hospital admissions) and there is a high potential for permanent neurologic disabilities. Many cases are missed on initial presentation. However, prompt diagnosis and treatment are the most important factors in outcome. Pathogenesis: Bacteria can gain access to the epidural space via: ) Hematogenous spread, ) Contiguous spread, 3) Direct inoculation The culprit organisms Staphylococcus aureus, Streptococci spp, Aerobic gram-negative rods Risk Factors Bacteremia Immunocompromise Direct Inoculation IVDA Diabetes Penetrating injuries CVC Chronic systemic diseases Decubitus ulcers Endocarditis, skin infections, UTI, etc... Alcoholism Epidural analgesia, spinal surgery Clinical Features The classic triad of fever, back, pain and neurlogic deficits is rare. However, most patients will present with at least one of the three. Pain is the most consistent feature midline (percussion tenderness), not relieved when lying down Fevers are variable Presence of fever is important, lack of fever is not helpful Neurologic abnormalities present late Diagnosis: Early recognition is difficult because of the infrequency of the disease and the non-specific nature of early symptoms. Not considering the diagnosis is often the reason why these infections are missed. MRI with contrast CT with IV contrast CT Myelogram Stage of disease (progression of an untreated abscess). Back pain. Nerve root pain 3. Motor weakness and bowel/bladder dysfunction 4. Paralysis Study of choice No other option (pacemaker, cochlear implant) Rarely done 3

4 High Risk EM Blood cultures: CBC: ESR: Fever: Patients are often bacteremic (especially if SEA was hematogenously spread Many patients will have an elevated CBC (but not all) Most patients have an elevated ESR, not prospectively studied; some feel it is useful in moderate risk patients Many, but not all patients are febrile Immediate drainage Intravenous antibiotics directed against staphylococci, streptococci, and aerobic gram-negative organisms (Vancomycin + Cefepime) Rhinocerebral zygomycosis (Mucormycosis) An infection that originates in the paranasal sinuses and extends to the brain. Most commonly affects patients with diabetes who are in DKA. However, there have been a few cases in immunocompetent individuals. Early diagnosis is critical for a better outcome. The zygomyces species are relatively resistant to anti-fungal treatment and thus aggressive surgical debridement is the cornerstone of therapy. The diagnosis is suspected on clinical grounds and confirmed with radiographic studies and histopath. Pathogenesis The organism likes acidic and high glucose conditions. Thus, a patient with DKA is an ideal host. The fungus is angioinvasive; ischemia and infarction of infected tissue is characteristic. The onset is often rapid. Spores are inhaled and deposit themselves in the nares. The infection then spreads to the paranasal sinuses, orbits, and the brain. Risk Factors Symptoms Signs Diabetes/DKA, metabolic acidosis Hematologic malignancies, organ transplantation Deferoxamine and iron overload Acute sinusitis Facial anesthesia Facial pain or ocular pain Necrotic lesions (not always present) Ocular involvement Cavernous sinus thrombosis Diagnosis Radiographic findings Intense inflammation Unilateral nasal mucosal inflammation and then bone erosion/extrasinus extension Endoscopic evaluation and biopsy Emergent evaluation by ENT Removing necrotic and devitalized tissue Antifungal therapy Correction of immunosupression and metabolic status 4

5 High Risk EM Select References and Further Reading Marshall JC, Maier RV, Jimenez M, et al. Source control in the management of severe sepsis and septic shock: an evidence-based review. Crit Care Med. 4 Nov;3( Suppl):S53-6 Darouiche RO. Spinal epidural abscess. N Engl J Med. 6 Nov 9;355(9):- Rigamonti D, Liem L, Sampath P, et al. Spinal epidural abscess: contemporary trends in etiology, evaluation, and management. Surg Neurol. 999 Aug;5():89-9 Curry WT Jr, Hoh BL, Amin-Hanjani S, et al. Spinal epidural abscess: clinical presentation, management, and outcome. Surg Neurol. 5 Apr;63(4):364-7 Kawashima A, LeRoy AJ. Radiologic evaluation of patients with renal infections. Infect Dis Clin North Am. 3 Jun;7(): Huang JJ, Tseng CC. Emphysematous pyelonephritis: clinicoradiological classification, management, prognosis, and pathogenesis. Arch Intern Med. Mar 7;6(6): Abrahamian FM, Moran GJ, Talan DA. Urinary tract infections in the emergency department. Infect Dis Clin North Am. 8 Mar;():73-87 Anaya DA, Dellinger EP. Necrotizing soft-tissue infection: diagnosis and management. Clin Infect Dis. 7 Mar ;44(5):75- Wong CH, Khin LW, Heng KS, et al. The LRINEC (Laboratory Risk Indicator for Necrotizing Fasciitis) score: a tool for distinguishing necrotizing fasciitis from other soft tissue infections. Crit Care Med. 4 Jul;3(7):535-4 Napolitano LM. Severe soft tissue infections. Infect Dis Clin North Am. 9 Sep;3(3):57-9 Hasham S, Matteucci P, Stanley PR, et al. Necrotising fasciitis. BMJ. 5 Apr 9;33(7495):83-3 DeShazo R, Chapin K, Swain R. Fungal sinusitis. N Engl J Med. 997 Jul 4;337(4):54-9 Kontoyiannis DP, Lewis RE. Invasive zygomycosis: Update on pathogenesis, clinical manifestations, and management. Infect Dis Clin North Am. 6 Sep;(3):58-67 Mantadakis E, Samonis G. Clinical presentation of zygomycosis. Clin Microbiol Infect. 9 Oct;5 Suppl 5:5-5