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SARS Update: Focus on Airway Management Robert C. Jones, M.D. LtCol, USAF, Medical Corps Staff Anesthesiologist Andrews Air Force Base, Maryland E-mail: rob@notbob.com Web site: http://www.notbob.com Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Overview A Brief History of the 2003 SARS epidemic The SARS Virus Diagnosis Treatment Lessons Learned from China/Canada Airway Management Guidelines Discussion Issues Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Brief History of SARS ? Zoonotic spread from unknown animal reservoir Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Brief History of SARS ? Zoonotic spread from unknown animal reservoir Nov 02: Index case in Guangdong Province, PRC; most early cases among food handlers (civets, raccoons…) Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Brief History of SARS ? Zoonotic spread from unknown animal reservoir Nov 02: Index case in Guangdong Province, PRC; most early cases among food handlers (civets, raccoons…) Feb 03: Hotel Metropole, HK, PRC Physician from Guangzhou (Superspreader) massive outbreak Hotel Metropole, Kowloon, HK, PRC Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Brief History of SARS ? Zoonotic spread from unknown animal reservoir Nov 02: Index case in Guangdong Province, PRC; most early cases among food handlers (civets, raccoons…) Feb 03: Hotel Metropole, HK, PRC Physician from Guangzhou (Superspreader) massive outbreak Mar 03: Amoy Gardens outbreak high prevalence of diarrheal disease due to poor sanitation design Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Brief History of SARS ? Zoonotic spread from unknown animal reservoir Nov 02: Index case in Guangdong Province, PRC; most early cases among food handlers (civets, raccoons…) Feb 03: Hotel Metropole, HK, PRC Physician from Guangzhou (Superspreader) massive outbreak Mar 03: Amoy Gardens outbreak high prevalence of diarrheal disease due to poor sanitation design Mar 03: SARS spreads to Beijing, Taiwan, Toronto, U.S. Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Brief History of SARS ? Zoonotic spread from unknown animal reservoir Nov 02: Index case in Guangdong Province, PRC; most early cases among food handlers (civets, raccoons…) Feb 03: Hotel Metropole, HK, PRC Physician from Guangzhou (Superspreader) massive outbreak Mar 03: Amoy Gardens outbreak high prevalence of diarrheal disease due to poor sanitation design Mar 03: SARS spreads to Beijing, Taiwan, Toronto, U.S. Apr 03: Virus identified, sequenced in record time Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Brief History of SARS ? Zoonotic spread from unknown animal reservoir Nov 02: Index case in Guangdong Province, PRC; most early cases among food handlers (civets, raccoons…) Feb 03: Hotel Metropole, HK, PRC Physician from Guangzhou (Superspreader) massive outbreak Mar 03: Amoy Gardens outbreak high prevalence of diarrheal disease due to poor sanitation design Mar 03: SARS spreads to Beijing, Taiwan, Toronto, U.S. Apr 03: Virus identified, sequenced in record time July 03: Epidemic declared over by WHO Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Timeline 774 Known Dead (9.1% fatality rate) Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS The SARS Coronavirus (SARS-CoV) Coronaviridae first identified in 1937 in chickens (avian infectious bronchitis) Crown-shaped peplomers surrounding RNA source of name (Corona = Crown in Latin) Responsible for common cold (2nd most common etiology after rhinoviridae) Exact number unknown: many don’t grow in cultures SARS virus can be grown in Vero culture (primate fibroblast cell line from 1962) Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Diagnosis: CDC Clinical Criteria Asymptomatic or mild respiratory illness Moderate respiratory illness Temperature of >100.4°F (>38°C)*, and One or more clinical findings of respiratory illness (e.g., cough, shortness of breath, difficulty breathing, or hypoxia). Severe respiratory illness Temperature of >100.4°F (>38°C)*, and One or more clinical findings of respiratory illness (e.g., cough, shortness of breath, difficulty breathing, or hypoxia), and – radiographic evidence of pneumonia, or – respiratory distress syndrome, or – autopsy findings consistent with pneumonia or respiratory distress syndrome without an identifiable cause Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Diagnosis: CDC Epidemiologic Criteria Travel (including transit in an airport) within 10 days of onset of symptoms to an area with current or previously documented or suspected community transmission of SARS (see Table below), or Close contact within 10 days (one incubation period) of onset of symptoms with a person known or suspected to have SARS. Table. Travel criteria for suspect or probable U.S. cases of SARS Area First date of illness onset for inclusion as reported case‡ Last date of illness onset for inclusion as reported case† China (Mainland) November 1, 2002 July 13, 2003 Hong Kong February 1, 2003 July 11, 2003 Hanoi, Vietnam February 1, 2003 May 25, 2003 Singapore February 1, 2003 June 14, 2003 Toronto, Canada April 1, 2003 July 18, 2003 Taiwan May 1, 2003 July 25, 2003 Beijing, China November 1, 2002 July 21, 2003 Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Diagnosis: CDC Laboratory Criteria Confirmed Detection of antibody to SARS-associated coronavirus (SARS-CoV) in a serum sample, or Detection of SARS-CoV RNA by RT-PCR confirmed by a second PCR assay, by using a second aliquot of the specimen and a different set of PCR primers, or Isolation of SARS-CoV. Negative Absence of antibody to SARS-CoV in a convalescent–phase serum sample obtained >28 days after symptom onset.** Undetermined Laboratory testing either not performed or incomplete. Case Classification*** Probable case: meets the clinical criteria for severe respiratory illness of unknown etiology and epidemiologic criteria for exposure; laboratory criteria confirmed or undetermined. Suspect case: meets the clinical criteria for moderate respiratory illness of unknown etiology, and epidemiologic criteria for exposure; laboratory criteria confirmed or undetermined. Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Diagnosis: WHO Suspect case 1. A person presenting after 1 November 2002 with history of: - high fever (>38 °C) AND - cough or breathing difficulty AND one or more of the following exposures during the 10 days prior to onset of symptoms: - close contact with a person who is a suspect or probable case of SARS; - history of travel, to an area with recent local transmission of SARS - residing in an area with recent local transmission of SARS 2. A person with an unexplained acute respiratory illness resulting in death after 1 November 2002, but on whom no autopsy has been performed AND one or more of the following exposures during to 10 days prior to onset of symptoms: - close contact with a person who is a suspect or probable case of SARS; - history of travel to an area with recent local transmission of SARS - residing in an area with recent local transmission of SARS Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Diagnosis: WHO Probable case 1. A suspect case with radiographic evidence of infiltrates consistent with pneumonia or respiratory distress syndrome (RDS) on chest Xray (CXR). 2. A suspect case of SARS that is positive for SARS coronavirus by one or more assays. 3. A suspect case with autopsy findings consistent with the pathology of RDS without an identifiable cause. Exclusion criteria A case should be excluded if an alternative diagnosis can fully explain (his or her) illness. Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Clinical Manifestations Incubation period: 2-10 days Prodrome: 1-2 days myalgia, fever, malaise Fever > 38°C Less commonly diarrhea Respiratory Phase: 3-7 days after onset; lasts to day 11-14 Cough, SOB, hypoxia Severity varies Falling SpO2 (<94%) ICU; SpO2 < 92% likely intubation Entire illness lasts 3 weeks if you don’t die; ? long term effects Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. Source: Loutfy, M, SARS: The Frontline Experience; Powerpoint presentation, 20 Oct 03 SARS Clinical Manifestations (cont’d) Extreme anxiety out of proportion to hypoxia Hyperglycemia Thrombocytopenia Leukopenia Lymphopenia Increased LDH, CK, ALT, lipase Increased severity in elderly (up to 50% mortality > age 65); rare, less severe in children Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Radiologic findings CXR: focal or multifocal airspace disease/consolidation bilateral ground glass opacities consistent with ARDS/SIRS; may be NORMAL High Contrast CT: can determine disease in patients with “normal” CXR; parenchymal and airspace disease evident Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Treatment As of Nov 03, no specific treatment supportive Antibiotics: azithromycin, ceftriaxone not useful against virus, may help if bacterial superinfection High-dose steroids in China avascular necrosis, other side effects Ribavirin used not recommended (hemolytic anemia) Experimental: TNF-alpha, protease inhibitors… Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Lessons Learned from China and Canada Meta-Issues: Misinformation Lack of Communication Lack of Personnel Assumptions Transfers Post-Traumatic Stress Quarantine language issues, WHO travel warning in Toronto between countries, governments, hospitals public health authorities underfunded health care system; unions and contracts; overtime issues Public health authorities assumed hospitals had adequate infection control ED ward long term care ED other hospitals (lots of opportunities for infection) Health-care workers, civilians; stigmatization of subsets of populace (e.g., Chinese) Legal issues: Canada had no legal definition of quarantine pre-SARS; difficulties enforcing home quarantine (e-mail, phone, videophone to read thermometer); people will cheat and go to work if not given paid leave No wakes, ritual washing of body caused stress Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Lessons Learned from China and Canada Hospital Infection Control: Wash your hands! Alcohol denatures proteins– good vs. enveloped viruses Single entry point for staff separate from patients Guard with personal protective equipment (PPE) to prevent unauthorized entry Non-critical hospital staff (med students) stay home Strict no visitor policy (difficult to enforce with hospital personnel patients) N95 mask + gown + no beards among ED staff for all patients during outbreak Change PPE after every high-risk encounter (respiratory dz vs. ankle fracture) Care with pens/cell phones/computers/pagers No hallway stretchers No humidified oxygen or nebs or BiPAP in ED send to ICU Limit staff contacts to minimum required for care (hard with sick colleagues) Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Airway Management High risk of transmission of SARS virus during airway manipulation/intubation 5/50 intubations in Toronto SARS transmitted 20 healthcare workers infected Conflicts among staff to avoid being the laryngoscopist for high-risk patients Intubation rarely emergency in SARS gradual decompensation over 12 hours should NOT be stat procedure (takes 5 minutes minimum to don appropriate protective equipment) 10-20% of patients will need to be intubated Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS High Risk Procedures laryngoscopy intubation airway suctioning neb treatment (use MDIs instead) bronchoscopy (including fiberoptic intubation) bagging via mask emesis care anything that causes patient to cough Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Intubation Guidelines Plan ahead! Will take at least 5 minutes to… Apply N95 mask, goggles, disposable footwear, gown, gloves, belt-mounted PAPR (powered air purifying respirator), head cover, extra gown, extra gloves; if no PAPR N95 mask, googles, disposable surgical cap, disposable full-face shield Most experienced intubationist (not resident) Reference: Anaesthesia and SARS, British Journal of Anaesthesia 90: 6, June 2003, 715-718 SARS Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. Intubation Guidelines (cont’d) Avoid awake fiberoptic intubation; consider surgical airway Plan for rapid sequence induction with skilled assistant available for cricoid pressure; be generous with sux unless contraindicated Minimal bagging pre-intubation: 5 mins preox with 100% FiO2 High-efficiency filter between facemask and bag Intubate and confirm correct placement Airway equipment sealed in double zip-locked bag and removed for decon Careful degowning/gloving with help of assistant Wash hands with alcohol-based cleanser prior to touching hair or face Reference: Anaesthesia and SARS, British Journal of Anaesthesia 90: 6, June 2003, 715-718 SARS Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. Discussion Issues Everyone should read intranet resource: HCW Surveillance Protocol for SARS– MGMC (links to CDC sources) PAPR availability at MGMC: Ortho space suits are kept where? Available to ED? Do we need to buy more for ICU, ED? Infectious Disease consultants: WRAMC. Phone #s in ICU, ED? ICU beds rate limiting step– 22 beds in Toronto’s North York hospital maxed out…Transfer MOU with other hospitals? Ambulance personnel trained/equipped (N95 masks, ?PAPR)? Quarantine issues: If hospital quarantined, policies for paying contractors, etc.? Sleeping arrangements, food, water? Training: Should we try a SARS drill starting from ED ICU OR to see how we do? Probably as important as mock code blue Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS Conclusions “The only thing we have to fear is LACK of fear itself” --former Deputy Treasury Secretary Lawrence Summers • SARS will recur– and may recur forever • SARS is a disease of healthcare workers out of proportion to the community • Until there is an effective treatment or vaccine, SARS will remain a lifethreatening diagnosis • The intangible costs of SARS (economic, post-traumatic) may rival the obvious effects (morbidity, mortality); unknown long-term effects • Protecting healthcare workers from SARS is difficult– takes time, money, communication, planning, training, communication… Copyright (C) 2004 Robert C. Jones, M.D. All Rights Reserved. SARS