SARS in the Emergency Department

SARS SARS in thein the

Emergency Emergency DepartmentDepartment

Aric Storck PGY2Aric Storck PGY2Resident Oral PresentationResident Oral Presentation

February 12, 2004February 12, 2004

OutlineOutline The anatomy of an outbreakThe anatomy of an outbreak

Diagnosis in the Emergency Diagnosis in the Emergency DepartmentDepartment

The Calgary Health RegionThe Calgary Health Region

SARSSARSa unique diseasea unique disease

Don’t know where it came Don’t know where it came fromfrom

Spread easily between peopleSpread easily between people

No vector requiredNo vector required

No geographical affinityNo geographical affinity

Mimics other diseasesMimics other diseases

Very effective spread in Very effective spread in hospitalhospital

Superspreader phenomenonSuperspreader phenomenon

SARS & the EDSARS & the EDa unique challengea unique challenge

SARS difficult to recognize early in SARS difficult to recognize early in course of illnesscourse of illness

Early accurate diagnosis critical in Early accurate diagnosis critical in preventing spread and avoidable preventing spread and avoidable mortalitymortality

the anatomy of the anatomy of an outbreakan outbreak

•November 19, 2002•First reported case – Fushan, Guandong

•November – January, 2003•Local spread within Guandong

•February 11, 2003•WHO advised of “atypical pneumonia”•305 sick, 5 dead

http://maps.expedia.com/

February 21February 21 Doctor from Doctor from

Guangdong checks Guangdong checks into ninth floor into ninth floor room in Metropole room in Metropole Hotel in Hong Hotel in Hong KongKong

Elderly woman Elderly woman from Toronto also from Toronto also stays at same hotelstays at same hotel

February 23February 23 Elderly woman Elderly woman

returns to Torontoreturns to Toronto Falls ill shortly afterFalls ill shortly after Cared for at home by Cared for at home by

her son her son

Another guest Another guest travels to Vietnamtravels to Vietnam 13 cases 13 cases

subsequently linked subsequently linked to index case at to index case at Metropole HotelMetropole Hotel

March 5

Patient A dies at home

March 7

Patient B falls sick and presents to hospital

Source: Mcgeer A. The Toronto outbreak. (Accessed January 31, 2004 at http://www.niaid.nih.gov/sars/meetings/05_30_03/pdf/mcgeer.pdf

March 7, 2003March 7, 2003Emergency DepartmentEmergency Department

•Patient B presents with respiratory symptoms

•Received nebulized salbutamol

•admitted


•Patient C•Rapid atrial fibrillation•In bed 1.5 metres away from B•Separated by curtain•Discharged home after nine hours

•Patient D•Pleural effusion/SOB•5 metres away from B•Admitted then d/c’d home March 10

B,C,D all cared for by same nurse

March 8March 8 Patient B transferred to ICUPatient B transferred to ICU Airborne isolation precautions initiated – Airborne isolation precautions initiated –

concerned about TBconcerned about TB

March 10March 10 Contact precautions initiatedContact precautions initiated

March 12March 12 WHO alerts world to “severe atypical WHO alerts world to “severe atypical

pneumonia” (SARS)pneumonia” (SARS)

March 13-14March 13-14 ““B” diesB” dies Five family members admitted to three different Five family members admitted to three different

hospitalshospitals

Back to our atrial Back to our atrial fibberfibber

Remember ….Remember …. March 7 – discharged from EDMarch 7 – discharged from ED

March 10March 10 became febrilebecame febrile

March 16March 16 To hospital via EMSTo hospital via EMS 9 hours in ED (all isolation precautions used)9 hours in ED (all isolation precautions used) ““C”s wife falls illC”s wife falls ill

March 21March 21 ““C” dies in ICUC” dies in ICU



People “C” infectedPeople “C” infected WifeWife Two other family Two other family

membersmembers Two paramedicsTwo paramedics One firefighterOne firefighter 5 ED staff5 ED staff 2 other hospital 2 other hospital

staffstaff

2 ED patients2 ED patients 7 visitors to ED7 visitors to ED ICU MD during ICU MD during

intubationintubation Transmitted to one Transmitted to one

member of familymember of family 3 ICU nurses at 3 ICU nurses at

intubationintubation One family member One family member

infectedinfected

What about the fellow with What about the fellow with the pleural effusion?the pleural effusion?

March 13March 13 ““D” falls ill – Symptoms resemble MID” falls ill – Symptoms resemble MI Brought to ED by EMSBrought to ED by EMS No precautions initiatedNo precautions initiated Admitted to CCUAdmitted to CCU


Patient “D”Patient “D” Develops renal failureDevelops renal failure Transferred to another hospital for Transferred to another hospital for

dialysisdialysis


People “D” infectedPeople “D” infected His wifeHis wife 1 ED patient1 ED patient 3 ED staff3 ED staff 1 housekeeper1 housekeeper 1 physician1 physician 2 hospital 2 hospital

technologiststechnologists 2 CCU patients2 CCU patients 7 CCU staff7 CCU staff 1 paramedic1 paramedic

Transmission from Transmission from those tothose to 6 family members6 family members 1 patient1 patient 1 medical clinic staff1 medical clinic staff 1 ED nurse1 ED nurse

21 ED staff 21 ED staff infectedinfected

3 prehospital staff3 prehospital staff

Source: CMAJ Aug. 19, 2003

November 2002 – November 2002 – May 2003May 2003

the final tallythe final tally WorldwideWorldwide

29 countries29 countries 8422 cases8422 cases 908 fatalities908 fatalities

CanadaCanada 438 cases438 cases

250 probable250 probable 188 suspect188 suspect

375 in Ontario375 in Ontario

Attack RatesAttack Rates Emergency Department NursesEmergency Department Nurses

Six 12-hour unprotected shifts where SARS exposure Six 12-hour unprotected shifts where SARS exposure possiblepossible

22.2% (8/36)22.2% (8/36) 13.6 cases per 1000 nursing hours13.6 cases per 1000 nursing hours

ICU NursesICU Nurses 3 unprotected hours3 unprotected hours 10.3% (4/39)10.3% (4/39) 2.4 cases per 1000 nursing hours2.4 cases per 1000 nursing hours

CCU NursesCCU Nurses 6 unprotected shifts6 unprotected shifts 60% (6/10)60% (6/10) 31.3 cases per 1000 nursing hours31.3 cases per 1000 nursing hours

Source: CMAJ Aug. 19, 2003

So how do we So how do we recognize SARS in recognize SARS in

the Emergency the Emergency Department?Department?

WHO Case Definition of WHO Case Definition of SARSSARS

Suspect CaseSuspect CaseRevised May 1, 2003Revised May 1, 20031.1. A person presenting after November 1, 2002 with history A person presenting after November 1, 2002 with history

of:of: high fever (>38 °C) high fever (>38 °C)

ANDAND

cough or breathing difficultycough or breathing difficulty

AND one or more of the following exposures during the 10 one or more of the following exposures during the 10 days prior to onset of symptoms:days prior to onset of symptoms:

close contact with a person who is a suspect or probable case of close contact with a person who is a suspect or probable case of SARSSARS

history of travel, to an area with recent local transmission of SARShistory of travel, to an area with recent local transmission of SARS residing in an area with recent local transmission of SARS residing in an area with recent local transmission of SARS

WHO Case Definition of WHO Case Definition of SARSSARS

Probable CaseProbable Case A suspect case with radiographic A suspect case with radiographic

evidence of infiltrates consistent with evidence of infiltrates consistent with pneumonia or ARDS on CXRpneumonia or ARDS on CXR

A suspect case that is positive for SARS A suspect case that is positive for SARS coronavirus by one or more assayscoronavirus by one or more assays

A suspect case with autopsy findings A suspect case with autopsy findings consistent with the pathology of RDS consistent with the pathology of RDS without an identifiable causewithout an identifiable cause

Is the WHO definition Is the WHO definition useful in the Emergency useful in the Emergency

Department?Department? CriticismsCriticisms

Based on studies of patients already in Based on studies of patients already in hospitalhospital

Based on common symptomsBased on common symptoms

Difficult to determine contact historyDifficult to determine contact history

How accurate is it?How accurate is it?

Rainer, Rainer, et alet al. Evaluation of WHO criteria for . Evaluation of WHO criteria for identifying patients with SARS out of hospital: identifying patients with SARS out of hospital:

prospective observational study. BMJ 2003; prospective observational study. BMJ 2003; 326: 1354-8.326: 1354-8.

ObjectivesObjectives Determine clinical and radiological features of SARSDetermine clinical and radiological features of SARS Evaluate accuracy of WHO case definitionEvaluate accuracy of WHO case definition

WhoWho 556 hospital staff, patients, relatives who had contact with confirmed 556 hospital staff, patients, relatives who had contact with confirmed

SARS patientSARS patient

WhereWhere SARS screening clinic in ED of tertiary care hospital in Hong KongSARS screening clinic in ED of tertiary care hospital in Hong Kong

Outcome Outcome Confirmed cases of SARS defined byConfirmed cases of SARS defined by

Known contact with SARS patientKnown contact with SARS patient Persistent fever (>38)Persistent fever (>38) Evidence of pneumoniaEvidence of pneumonia Consistent course of illnessConsistent course of illness Did not respond to antibiotics within 48 hoursDid not respond to antibiotics within 48 hours

NB: serological testing not available at this timeNB: serological testing not available at this time

Symptoms more common Symptoms more common among patients who did not among patients who did not

develop SARSdevelop SARS Cough - 72% vs 64% p=0.12Cough - 72% vs 64% p=0.12 Sputum production – 29% vs 26% Sputum production – 29% vs 26%

p=0.52p=0.52 Sore throat – 39% vs 35% p=0.53Sore throat – 39% vs 35% p=0.53 Runny nose – 33% vs 26% p=0.20Runny nose – 33% vs 26% p=0.20

Significant findings more Significant findings more common among SARS patientscommon among SARS patients

(p<0.05)(p<0.05) SymptomsSymptoms

Fever – 81% vs 37%Fever – 81% vs 37% Chills – 54% vs 21%Chills – 54% vs 21% Malaise – 34% vs 20%Malaise – 34% vs 20% Myalgia – 27% vs 12%Myalgia – 27% vs 12% Rigor – 12% vs 4%Rigor – 12% vs 4% Neck pain - 3% vs Neck pain - 3% vs

0.2%0.2% loss of appetite 5% vs loss of appetite 5% vs

1%1% SOB – 12% vs 7% SOB – 12% vs 7% Vomiting – 6% vs 2%Vomiting – 6% vs 2% Diarrhea – 7% vs 3%Diarrhea – 7% vs 3%

SignsSigns Higher heart rateHigher heart rate Lower sBPLower sBP Higher tempHigher temp No difference in RRNo difference in RR

NB: of respiratory NB: of respiratory symptoms only SOB symptoms only SOB was significantwas significant

Predictive value of WHO Predictive value of WHO criteriacriteria

Odds ratios for Odds ratios for predicting SARSpredicting SARS

Fever 12.0 (6.8-21.0)Fever 12.0 (6.8-21.0)

Cough 1.0 (0.6-1.7)Cough 1.0 (0.6-1.7)

SOB 1.5 (0.7-3.5)SOB 1.5 (0.7-3.5)

CXR infiltrate 32.1 (18.0-57.3)CXR infiltrate 32.1 (18.0-57.3)

ConclusionsConclusions WHO criteria is based on respiratory WHO criteria is based on respiratory

symptoms which are uncommon in early symptoms which are uncommon in early SARSSARS

WHO criteria miss 74% of SARS cases WHO criteria miss 74% of SARS cases in the pre-hospital settingin the pre-hospital setting

Radiological infiltrates often proceed Radiological infiltrates often proceed fever in early SARS - thus CXR fever in early SARS - thus CXR mandatory for SARS screeningmandatory for SARS screening

Wong W, et al. Accuracy of clinical Wong W, et al. Accuracy of clinical diagnosis versus the WHO case diagnosis versus the WHO case

definition in the Amoy Garden SARS definition in the Amoy Garden SARS cohort. CJEM 2003;5(6):384-91.cohort. CJEM 2003;5(6):384-91.

ObjectiveObjective Compare WHO case definition with ED Compare WHO case definition with ED

physician clinical diagnosisphysician clinical diagnosis

WhoWho Retrospective cohort of 818 residents of Retrospective cohort of 818 residents of

Amoy Gardens presenting to a SARS Amoy Gardens presenting to a SARS screening clinic during a 2 month screening clinic during a 2 month outbreakoutbreak

Amoy GardensAmoy Gardens Largest community Largest community

outbreak in worldoutbreak in world 323 resident cases323 resident cases

37 deaths37 deaths 18% of all Hong 18% of all Hong

Kong casesKong cases Spread linked toSpread linked to

Faulty sewageFaulty sewage Poor ventilationPoor ventilation

OutcomesOutcomes Confirmed SARSConfirmed SARS

Clinical SARS and virological confirmationClinical SARS and virological confirmation

UndeterminedUndetermined Clinical SARS without virology Clinical SARS without virology

confirmation (lab testing not performed or confirmation (lab testing not performed or incomplete)incomplete)

Non-SARSNon-SARS Final diagnosis unrelated to SARSFinal diagnosis unrelated to SARS

ResultsResults SARS – 205 casesSARS – 205 cases Undetermined SARS – 35 casesUndetermined SARS – 35 cases Non-SARS – 581 casesNon-SARS – 581 cases

NB: disease prevalence = 26% in NB: disease prevalence = 26% in study populationstudy population

Table 2. WHO case definition criteria by final diagnosisTable 2. WHO case definition criteria by final diagnosis

Presenting Presenting features*features*

YesYes NoNo YesYes NoNo

1. ED temperature 1. ED temperature >38>38 o oCC

129 (63)129 (63) 75 (37)75 (37) 61 (11)61 (11) 485 (89)485 (89)

2. Contact history2. Contact history 187 (91)187 (91) 18 (9)18 (9) 466 (81)466 (81) 112 (19)112 (19) Social†Social† 130 (63)130 (63) NANA 390 (84)390 (84) NANA Close‡Close‡ 28 (14)28 (14) NANA 56 (12)56 (12) NANA Clustering§Clustering§ 25 (12)25 (12) NANA 12 (3)12 (3) NANA Health care worker¶Health care worker¶ 4 (2)4 (2) NANA 8 (1)8 (1) NANA 3. Respiratory 3. Respiratory symptoms (any)symptoms (any)

101 (49)101 (49) 104 (51)104 (51) 237 (41)237 (41) 338 (59)338 (59)

DyspneaDyspnea 10 (5)10 (5) 195 (95)195 (95) 20 (4)20 (4) 554 (96)554 (96) CoughCough 95 (46)95 (46) 110 (54)110 (54) 223 (39)223 (39) 352 (61)352 (61) SputumSputum 19 (9)19 (9) 185 (91)185 (91) 53 (9)53 (9) 522 (91)522 (91) WHO criteria 1, 2 WHO criteria 1, 2 and 3**and 3**

87 (42)87 (42) 118 (58)118 (58) 78 (14)78 (14) 497 (86)497 (86)

Abnormal chest x-Abnormal chest x-ray††ray††

177 (86)177 (86) 24 (14)24 (14) 66 (20)66 (20) 258 (80)258 (80)

Note: Column totals may not equal diagnostic group totals because of missing data. Percentages are based on available data.Note: Column totals may not equal diagnostic group totals because of missing data. Percentages are based on available data.*Findings documented at the time of the ED visit.*Findings documented at the time of the ED visit.†Social contact refers to persons who did not meet criteria for close contact but had contact with a SARS case.†Social contact refers to persons who did not meet criteria for close contact but had contact with a SARS case.‡Close contact refers to persons who cared for, lived with or had direct contact with respiratory secretions and body fluids of a ‡Close contact refers to persons who cared for, lived with or had direct contact with respiratory secretions and body fluids of a person with SARS.person with SARS.§Clustering refers to an exposure where more than 2 family members were infected with SARS.§Clustering refers to an exposure where more than 2 family members were infected with SARS.¶Health care workers were patients working in private clinics or public hospitals who had contact with SARS cases.¶Health care workers were patients working in private clinics or public hospitals who had contact with SARS cases.**Patients with all 3 criteria meet the WHO case definition for suspected SARS.**Patients with all 3 criteria meet the WHO case definition for suspected SARS.††Abnormal chest x-ray was defined as unilateral or bilateral haziness, consolidation, infiltration or ground-glass abnormality on ††Abnormal chest x-ray was defined as unilateral or bilateral haziness, consolidation, infiltration or ground-glass abnormality on plain posterior-anterior chest x-ray, on presentation.plain posterior-anterior chest x-ray, on presentation.

Confirmed SARS

(n=205)

Non-SARS

(n=581)

Diagnostic accuracy of Diagnostic accuracy of WHO case definitionWHO case definition

Diagnosis Diagnosis by WHO by WHO definitiondefinition

Final Final Diagnosis: Diagnosis: Confirmed Confirmed

SARSSARS

Final Final DiagnosisDiagnosis

: Non-: Non-SARSSARS

TotalTotal

SARSSARS 8787 7878 165165Non-SARSNon-SARS 118118 497497 615615TotalTotal 205205 575575 780780 Sensitivity 42.4%Sensitivity 42.4% Specificity 86.4%Specificity 86.4% Accuracy 74.9%Accuracy 74.9% PPV 52.7PPV 52.7 NPV 80.8NPV 80.8 NB: 6 patients charts incompleteNB: 6 patients charts incomplete

Diagnostic Accuracy of ED Diagnostic Accuracy of ED diagnosisdiagnosis

Sensitivity 90.7%Sensitivity 90.7% Specificity 95.7%Specificity 95.7% Accuracy 94.4%Accuracy 94.4% PPV 88.2%PPV 88.2% NPV 96.7%NPV 96.7%

ED ED DiagnosisDiagnosis

Final Final Diagnosis: Diagnosis: Confirmed Confirmed

SARSSARS

Final Final DiagnosisDiagnosis

: Non-: Non-SARSSARS

TotalTotal

SARSSARS 186186 2525 211211Non-SARSNon-SARS 1919 556556 575575TotalTotal 205205 581581 786786

ConclusionsConclusions WHO definition would miss 58% of WHO definition would miss 58% of

SARSSARS

Clinical judgement superior to WHO Clinical judgement superior to WHO criteriacriteria

CaveatsCaveats Extremely high disease prevalence would Extremely high disease prevalence would

affect PPV/NPVaffect PPV/NPV

So if the WHO So if the WHO criteria doesn’t criteria doesn’t work in the ED, work in the ED,

how do I recognize how do I recognize SARS?SARS?

Wong W, et al. Early clinical Wong W, et al. Early clinical predictors of SARS in the ED. predictors of SARS in the ED.

CJEM 2004;6(1):xxCJEM 2004;6(1):xx ObjectivesObjectives

To assess diagnostic predictors To assess diagnostic predictors available in the ED with final diagnosis available in the ED with final diagnosis of SARSof SARS

WhoWho Same cohort as previous studySame cohort as previous study

Table 2. Univariable association of key predictors for patients with a final diagnosis of severe acute respiratory syndrome (SARS)

Presenting features

Confirmed SARS (n = 205),

no. (and %)

Non-SARS(n = 581),

no. (and %)

LR p value

Yes No Yes No

Chills and rigors 91 (44) 114 40 (7) 535 6.4 <0.000 Myalgia 85 (41) 120 38 (7) 537 6.3 <0.000 Temperature >38°C 129 (63) 75 61 (11) 485 5.7 <0.000 Malaise 67 (33) 138 44 (8) 530 4.3 <0.000 Abnormal chest x-ray 177 (86) 24 66 (20) 258 4.3 <0.000 History of fever 196 (96) 9 195 (34) 380 2.8 <0.000 Sore throat 24 (12) 181 102 (18) 472 0.7 0.04 Abdominal pain 2 (1) 203 24 (4) 550 0.2 0.01 Headache 31 (15) 174 60 (10) 514 1.5 0.08 Dyspnea 10 (5) 195 20 (4) 554 1.4 0.39 Cough 95 (46) 110 223 (39) 352 1.2 0.06 Sputum 19 (9) 185 53 (9) 522 1.0 0.97 Nausea 6 (3) 199 19 (4) 556 0.9 0.79 Vomiting 4 (2) 201 15 (3) 559 0.8 0.59 Rhinitis 26 (13) 179 102 (18) 473 0.7 0.09 Diarrhea 6 (3) 199 29 (5) 546 0.6 0.19

*Findings documented at the time of the ED visit.LR = likelihood ratio.Note: Column totals may not equal diagnostic group totals because of missing data.

Table 3. Association of exposure type with final diagnosis*

Type of contactConfirmed SARS (n = 205),

no. (and %)Non-SARS (n = 578),

no. (and %) LR

None 18 (9) 112 (19) 0.5

Social† 130 (63) 390 (67) 0.9

Close‡ 28 (14) 56 (10) 1.4

Clustering§ 25 (12) 12 (2) 6.0

Health care worker¶ 4 (2.0) 8 (1.4) 1.4

LR = likelihood ratio*The p value for linear trend for all types of contact is <0.000.†Social contact refers to persons who did not meet criteria for close contact but had contact with a SARS case.‡Close contact refers to persons who cared for, lived with or had direct contact with respiratory secretions and body fluids of a person with SARS.§Clustering refers to an exposure where more than 2 family members were infected with SARS.¶Health care workers were patients working in private clinics or public hospitals who had contact with SARS cases.Note: column totals may not equal diagnostic group totals because of missing data.

Table 4. Complete blood count results by final diagnosis (N = 176)

Variable

Confirmed SARS (n = 71),

no. (and %)Non-SARS (n = 105),

no. (and %) LR p value*

White blood cell count

<4000 13 (18) 13 (12) 1.5

<0.0004000-5999 25 (35) 20 (19) 1.86000-7999 23 (32) 21 (20) 1.6

>8000 10 (14) 51 (49) 0.3

Neutrophil

<3000 20 (28) 13 (11) 2.5

0.0023000-3999 16 (23) 21 (18) 1.34000-4999 16 (23) 24 (21) 1.1

>5000 19 (26) 56 (49) 0.5

Lymphocyte

<1000 32 (45) 9 (9) 5.0

<0.0001000-1499 29 (41) 19 (18) 2.31500-1999 7 (10) 32 (30) 0.3

>2000 3 (4) 45 (43) 0.1

Platelets (´103)

<100 5 (7) 2 (2) 3.5

<0.000100-199 49 (69) 22 (21) 3.3200-299 17 (24) 66 (63) 0.4

>300 0 (0) 15 (14) 0.0

LR = likelihood ratio*p values based on linear trend analysis.

Table 5. Logistic regression analysis of key predictor variables for all patients (n = 786)

Clinical predictorAdjusted

OR* 95% CI p value Crude OR† 95% CI p value

Abnormal chest x-ray

17.4 8.8-34.0 <0.000 28.8 17.4-47.8 <0.000

History of fever 9.7 3.6-26.4 <0.000 42.4 21.3-84.6 <0.000Temperature >38°C 6.4 3.2-12.8 <0.000 13.5 9.2-20.0 <0.000

Myalgias 5.5 2.6-11.3 <0.000 10.0 6.5-15.4 <0.000

Chills 4.0 2.0-8.1 <0.000 10.7 7.0-16.3 <0.000

Significant contact‡ 2.6 1.2-5.5 0.01 2.5 1.7-3.8 <0.000

Diarrhea 0.1 0.08-0.7 0.01 0.6 0.2-1.4 0.21Malaise 3.8 0.9-10.2 0.06 5.8 3.8-8.9 <0.000

Headache 1.4 0.6-3.2 0.50 1.5 1.0-2.4 0.07

Nausea 1.4 0.7-3.4 0.82 0.9 0.3-2.2 0.79

Abdominal pain 1.2 0.6-18.2 0.10 0.2 0.01-1.0 0.03

Sore throat 1.0 0.4-2.7 0.93 0.6 0.4-1.0 0.04Cough 1.0 0.5-1.8 0.93 1.4 1.0-1.9 0.06

Dyspnea 0.9 0.2-3.9 0.89 1.4 0.7-3.1 0.38

Rhinitis 0.7 0.3-1.6 0.37 0.7 0.4-1.1 0.10

Sputum 0.5 0.2-1.5 0.23 1.0 0.6-1.7 0.98

Vomiting 0.5 0.1-1.9 0.62 0.7 0.2-1.4 0.60

OR = odds ratio; CI = confidence interval*Adjusted ORs were determined by controlling for other predictors in the multiple logistic regression model.†Crude ORs were derived from univariate analysis without adjustment.‡Significant contact was defined by either "close contact," "clustering" or "health care worker." See Table 3 for a detailed description of these terms.Note: Shaded cells highlight the most powerful statistically significant clinical predictors of a final diagnosis of SARS.

ConclusionsConclusions WHO case definition not sufficiently WHO case definition not sufficiently

sensitive or specific to guide dispositionsensitive or specific to guide disposition

Positive predictorsPositive predictors Fever, lymphopenia, abnormal CXR, Fever, lymphopenia, abnormal CXR,

thrombocytopenia, myalgia, chillsthrombocytopenia, myalgia, chills

Negative predictorsNegative predictors DiarrheaDiarrhea

Cough and dyspnea not useful predictors in Cough and dyspnea not useful predictors in the EDthe ED

Chen S, et al. Sequential Chen S, et al. Sequential symptomatic analysis in probable symptomatic analysis in probable SARS cases. Annals of Emergency SARS cases. Annals of Emergency

Medicine 2004;43:27-33.Medicine 2004;43:27-33. ObjectiveObjective To determine chronology of symptoms in early To determine chronology of symptoms in early

SARSSARS

MethodsMethods Prospective cohort of febrile patients with Prospective cohort of febrile patients with

exposure risk presenting to Taipei hospitalexposure risk presenting to Taipei hospital SARS confirmed by PCRSARS confirmed by PCR

OutcomeOutcome Clinical symptoms over time in SARS and non-Clinical symptoms over time in SARS and non-

SARS casesSARS cases

ResultsResults SARS – 79SARS – 79

Non-SARS - 220Non-SARS - 220

Percentage of patients with Percentage of patients with initial symptoms and CXR initial symptoms and CXR

findingsfindings

Source: Chen et al. Annals of Emerg Med 2004

Chronology of symptomsChronology of symptoms

Sequential symptoms in SARS patients Sequential symptoms in non-SARS patients

Source: Chen et al. Annals of Emerg Med 2004

ConclusionsConclusions Characteristic SARS chronology: diarrhea, Characteristic SARS chronology: diarrhea,

myalgias & fever, without coryza or sore myalgias & fever, without coryza or sore throat, followed by later LRTI symptomsthroat, followed by later LRTI symptoms SARS patients 70% (CI 0.60-0.80)SARS patients 70% (CI 0.60-0.80) Non-SARS patients 3.2% (CI 0.008-0.05)Non-SARS patients 3.2% (CI 0.008-0.05)

Cough before feverCough before fever SARS patients 7.6% (CI 0.02-0.13)SARS patients 7.6% (CI 0.02-0.13) Non-SARS patients 51% (CI 0.44-0.58)Non-SARS patients 51% (CI 0.44-0.58)

Sore throat & coryza Sore throat & coryza rare in SARS but common in other URTI’srare in SARS but common in other URTI’s

CXR infiltrate on presentationCXR infiltrate on presentation SARS 75% (0.65-0.85)SARS 75% (0.65-0.85) Non-SARS 10% (0.06-0.14)Non-SARS 10% (0.06-0.14)

CXR infiltrate before feverCXR infiltrate before fever SARS 41% (0.30-0.51)SARS 41% (0.30-0.51)

Source: Peiris J, et al. The Severe Acute Respiratory Syncrome. NEJM 2003;349:2431-41

Clinical FeaturesClinical Featuresnot a typical atypical pneumonianot a typical atypical pneumonia

Radiological FindingsRadiological Findings Initial CXR abnormal in 60-100% of casesInitial CXR abnormal in 60-100% of cases

Often precedes respiratory symptomsOften precedes respiratory symptoms Depends on interval between onset and presentationDepends on interval between onset and presentation CT abnormal in 67% of patients with initial normal CXRCT abnormal in 67% of patients with initial normal CXR

Frequent findingsFrequent findings Ground class opacitiesGround class opacities

Do not obscure underlying vesselsDo not obscure underlying vessels Focal consolidationsFocal consolidations pneumomediastinumpneumomediastinum

Do not typically haveDo not typically have Mediastinal lymphadenopathyMediastinal lymphadenopathy CavitationCavitation Pleural effusionsPleural effusions

Source: Peiris J, et al. The Severe Acute Respiratory Syncrome. NEJM 2003;349:2431-41

Laboratory findingsLaboratory findings Multiple frequently observed Multiple frequently observed

abnormal lab findings including:abnormal lab findings including:

LymphocytopeniaLymphocytopenia ThrombocytopeniaThrombocytopenia Elevated D-dimerElevated D-dimer Elevated ALT, CK, LDHElevated ALT, CK, LDH

None distinguish between SARS and None distinguish between SARS and other causes of pneumoniaother causes of pneumonia

Emergency departments are the Emergency departments are the point of first contact and the primary point of first contact and the primary destination for the sickest patients in destination for the sickest patients in the systemthe system

ED staff evaluate and treat patients ED staff evaluate and treat patients before the risks and diagnostic before the risks and diagnostic possibilities are knownpossibilities are known

CAEP. Implications of the SARS CAEP. Implications of the SARS outbreak for Canadian emergency outbreak for Canadian emergency

departments.departments.CJEM 2003;5(5):343-7CJEM 2003;5(5):343-7

““As the Toronto SARS crisis As the Toronto SARS crisis demonstrated, the current demonstrated, the current practice of housing large practice of housing large numbers of sick admitted numbers of sick admitted

patients for prolonged times in patients for prolonged times in open, densely-populated EDs open, densely-populated EDs is a potential public health is a potential public health

hazard”hazard”

RECOMMENDATIONS RECOMMENDATIONS Develop national standards for emergency Develop national standards for emergency

department design and operations. department design and operations.

Regional resources to be developed to implement Regional resources to be developed to implement infection control aspects of ED design and infection control aspects of ED design and operations. operations.

Develop relationships and enhance communication Develop relationships and enhance communication between public health and the emergency between public health and the emergency community. community.

Eliminate ED overcrowding by ensuring adequate Eliminate ED overcrowding by ensuring adequate long-term and acute-care resources and enforcing long-term and acute-care resources and enforcing strict adherence to occupancy limits. strict adherence to occupancy limits.

Rapid triage assessment of arriving patients by Rapid triage assessment of arriving patients by appropriately trained nurses at all times should be appropriately trained nurses at all times should be a national standard. a national standard.

SARSSARSin thein the

Calgary Health Calgary Health RegionRegion

2003 Outbreak2003 Outbreak 117 patients investigated117 patients investigated

1 hospitalized1 hospitalized 15 assessed in ED15 assessed in ED

10 Suspect Cases10 Suspect Cases 1 hospitalized1 hospitalized 1 assessed in ED1 assessed in ED

5 Probable Cases5 Probable Cases 1 hospitalized1 hospitalized 1 assessed in ED1 assessed in ED

Phases of Phases of SurveillanceSurveillance

Phase 0Phase 0 No SARS cases identified anywhere in the worldNo SARS cases identified anywhere in the world

Family physicians do not have a surveillance roleFamily physicians do not have a surveillance role screening required in ED onlyscreening required in ED only notification of MOH required if patient admitted to notification of MOH required if patient admitted to

hospitalhospital

Phase 1Phase 1 Cases or outbreaks occuring outside North Cases or outbreaks occuring outside North

AmericaAmerica family physicians have surveillance role of identifying family physicians have surveillance role of identifying

cases in the communitycases in the community ED screening requiredED screening required MOH to be notified of positive screensMOH to be notified of positive screens

Phase 2Phase 2 Cases occurring in North America, but not in AlbertaCases occurring in North America, but not in Alberta

family physicians have surveillance role of identifying family physicians have surveillance role of identifying cases in communitycases in community

ED screening requiredED screening required notification of MOH if patient screens positivenotification of MOH if patient screens positive

Phase 3Phase 3 Transmission of SARS in a well-defined setting in Transmission of SARS in a well-defined setting in

Alberta (e.g. health care facility, households)Alberta (e.g. health care facility, households) stand-alone assessment centres operationalstand-alone assessment centres operational ED and family physicians have role of telephone triage in the ED and family physicians have role of telephone triage in the

communitycommunity Notification of MOH only if patient seen in ED or Notification of MOH only if patient seen in ED or

outpatient office and screens positiveoutpatient office and screens positive


Phase 4Phase 4 Community spread within Alberta, not containedCommunity spread within Alberta, not contained

stand alone assessment centres operationalstand alone assessment centres operational family physicians have role of telephone triage of family physicians have role of telephone triage of

cases in the communitycases in the community Notification of MOH only if patient seen in ED or Notification of MOH only if patient seen in ED or

outpatient office and screens positiveoutpatient office and screens positive

Phase 5Phase 5 Widespread disease across Alberta/CanadaWidespread disease across Alberta/Canada

stand alone assessment centres operationalstand alone assessment centres operational family physicians have role of telephone triage of family physicians have role of telephone triage of

cases in the communitycases in the community Notification of MOH required only if patient is seen Notification of MOH required only if patient is seen

in office and screens positivein office and screens positive


Client enters ED with fever andrespiratory symptoms

Triage

Consider RespiratoryEtiquette Client proceeds to ER waiting

Room with fever and respiratorysymptomsED MD assessment

•Fever >38, and cough or difficulty breathing•AND Positive response to:

•“Did you travel to Asia in the 10 days before you got sick?”

•OR•“Did you live with or were in close contact with someone who has a similar illness and who traveled to Asia in the 10 days before they became sick?”

•OR•“Are you a health care worker in the CHR?”

•AND radiographic infiltrates consistent with pneumonia or ARDS•AND clinical condition warrants admission to hospital

Algorithm for Enhanced Surveillance for Severe Respiratory Illness Phase 0

Yes No

Treat as clinically indicatedNo further action

•Arrange for admission, continue isolation, use droplet precautions•Complete SRI Form 2 for ED Staff contact follow-up (if required)

•Admit to an inpatient isolation room or negative pressure room•Continue droplet precautions•Notify infection control•Initiate “Rule out” lab testingED MD to notify MOH of case under

Investigation (CUI)

Health CanadaHealth CanadaInfection Control GuidelinesInfection Control Guidelines

Non-outbreak settingNon-outbreak setting Screening questions asked >1 metre from Screening questions asked >1 metre from

patientpatient1.1. Fever or Respiratory Symptoms?Fever or Respiratory Symptoms?2.2. Travel to Asia past 2 weeks?Travel to Asia past 2 weeks?3.3. Contact with somebody who travelled to Asia past 2 Contact with somebody who travelled to Asia past 2

weeks?weeks?4.4. Health care worker?Health care worker?

If Yes to Q1 and one of Q2-Q4If Yes to Q1 and one of Q2-Q4 HCW should don surgical mask and eye protectionHCW should don surgical mask and eye protection Patient should don surgical mask and hand hygienePatient should don surgical mask and hand hygiene Patient should be moved to separate areaPatient should be moved to separate area Persons with patient should don surgical maskPersons with patient should don surgical mask

Client enters ED with feverand respiratory symptoms

Triage to institute SARS infection controlprocedures

•Fever >38, and cough or difficulty breathing•AND Positive response to:

•“Did you travel to zone of emergencce in the 10 days before you got sick?”

•OR•“Did you live with or were in close contact with someone who has a similar illness and who traveled to the zone of emergence in the 10 days before they became sick?”

•OR•“Are you a health care worker in the CHR?”

•OR•“Have you handled live SARS-CoV in a lab?”

Algorithm for Enhanced Surveillance for Severe Respiratory Illness Phase 1 & 2

Radiologic evidence consistent with pneumonia or ARDS

NoYes

•Classify as suspect case•report to MOH•treat as clinically indicated

Clinical condition warrantsadmission

NoYes

•Isolation and infection control•complete SRI Form 2 for

ED staff contacts•ED to fax Form 2 to PH•initiate R/O lab testing

•Arrange for admission•continue infection control•complete SRI forms 1 & 2•initiate R/O lab testing•negative pressure room

Health CanadaHealth CanadaInfection Control GuidelinesInfection Control Guidelines

Outbreak settingOutbreak setting Screening questions asked >1 metre from patientScreening questions asked >1 metre from patient

1.1. Fever or Respiratory Symptoms?Fever or Respiratory Symptoms?

If yes to Q1 don N95 mask and eye protection, If yes to Q1 don N95 mask and eye protection, isolate patient, patient to don surgical mask, then isolate patient, patient to don surgical mask, then ask:ask:

2.2. Travel to SARS-affected area in past 2 weeks?Travel to SARS-affected area in past 2 weeks?3.3. Contact with somebody who traveled to this area past 2 Contact with somebody who traveled to this area past 2

weeks?weeks?4.4. Health care worker?Health care worker?5.5. Been to SARS affected hospitalBeen to SARS affected hospital

If Yes to one of Q2-Q4If Yes to one of Q2-Q4 Immediately notify infection controlImmediately notify infection control

Surveillance AlgorithmSurveillance Algorithmcommentscomments

Based on WHO case definitionBased on WHO case definition

Phase 0 only screens the sickest patientsPhase 0 only screens the sickest patients

Should phases of surveillance be Should phases of surveillance be redefined?redefined? Eg: Phase 0 to include isolated & contained Eg: Phase 0 to include isolated & contained

casescases

Our Emergency Our Emergency DepartmentsDepartments

Negative pressure roomsNegative pressure rooms

SARS suppliesSARS supplies Surgical masksSurgical masks N95 masksN95 masks GownsGowns GlovesGloves PAPR’sPAPR’s Rule out lab kitRule out lab kit

SARSSARSthe presentthe present

SARS UpdateSARS Update September 2003September 2003

Medical researcher in SingaporeMedical researcher in Singapore

December 16, 2003 - presentDecember 16, 2003 - present 3 confirmed cases3 confirmed cases 1 probable case1 probable case

All in southern ChinaAll in southern China

No epidemiological link between casesNo epidemiological link between cases

SARSSARSthe futurethe future

??????

Where did SARSWhere did SARS come from?come from?

Is it still there?Is it still there?

Animal Reservoirs?Animal Reservoirs? Early cases included restaurant Early cases included restaurant

and market workers who handled and market workers who handled exotic meatsexotic meats

Virus very similar to SARS-CoV Virus very similar to SARS-CoV cultured from palm civets and cultured from palm civets and raccoon dogsraccoon dogs

SARS-CoV now found in domestic SARS-CoV now found in domestic cats and ferretscats and ferrets

Definitive animal reservoir not yet Definitive animal reservoir not yet identifiedidentified

Himalayan palm civet

Raccoon dog

How is it transmitted?How is it transmitted? Aerosol vs dropletAerosol vs droplet Are N95 masks really necessaryAre N95 masks really necessary Breakthrough cases in full PPEBreakthrough cases in full PPE

Superspreaders?Superspreaders?

““The fact that SARS was The fact that SARS was contained less than four contained less than four

months after the first months after the first global alert, despite the global alert, despite the

absence of a vaccine, absence of a vaccine, effective treatment, or effective treatment, or reliable point-of-care reliable point-of-care diagnostic test, is a diagnostic test, is a

triumph of public health triumph of public health and a tribute to the power and a tribute to the power of political commitment.”of political commitment.”WHO – November 2003

the endthe end

Documents

SARS in the Emergency Department