Traffic Control Strategy in Traffic Control Strategy in SARS Outbreak ControlSARS Outbreak Control

Muh-Yong Yen, Yu-sen E. Lin, Ih-Jen Su, Mei-Shang Ho, Kuang-Huan Tan,

Chen-Hsen Lee

Jen-Ai Municipal Hospital, Taipei City

Veterans General Hospital, Kaohsiung

STOP SARS at the bedsideSTOP SARS at the bedside

Life finds the way

SARS is looking for the niche/leak to jump into next

victims (HCW)

Niche, leakNiche, leak

Waves nichereasons/solution

1st wave 20-30 % mask & glove2nd wave 3-5 % PPE, NPIR3rd wave 1 – 0.1 % intubation teamNext wave ??

New concept !New concept !

HCW first, Patient next

Traffic Control

Myth of negative pressure

IntroductionIntroduction

The health officials shut down and quarantine the hospital to control nosocomial transmission.

More than one thousand persons afected, chaos and panic rapidly ensued within the hospital.

The president of Taiwan made an executive decision to evacuate the hospital within 36 hours.

METHODSMETHODS

Renovation of hospitalsA hospital: 67 bedsB hospital: 18 beds

Comparison Hospitals746 NPIRs

Hospital A, Hospital A, 松山松山 The first floor is an admission office

that has a special pathway which leads the patient directly to the elevator

The third floor is designated ward for

suspect SARS cases, the fourth floor is for probable or confirmed cases.

Hospital A, Hospital A, 松山松山 A residential apartment within 2 meters to

the east. A “negative-pressure like” environment all windows due east were sealed air tight. A 16-inch exhaust fan was installed in

patient’s rooms due west.All doors/bottom gap of patient’s rooms were

sealed.

Hospital A, Hospital A, 松山松山The exits and staircase of each floor was

sealed to prevent air interflow between floors.

A separate central air conditioning system was used to circulate air within each floor with 50% of air-exchange rate.

All of the exhaust air to the west was blow to a 60 by 30 meters restricted area,

Hospital B, Hospital B, 松德松德a 4-story healthcare facility for patients

with tbc / chronic diseases.the first floor is the admission office with

a special pathway to the elevator. The second floor is an 18-bed patient

ward in negative pressure isolated room (NPIR).

The path to elevator was isolated with wooden/acrylic boards to differentiate the pathways for patients from the HCWs.

There is a separate entrance/exit for each HCW to enter/leave the ward to avoid crossing or overlapping with the traffic of contamination zone that the patients have passed through.

Each zone was clearly designated by wooden/plastic barriers

To avoid casual breakthrough by any directly passing and contacting from contaminated zones into clean zones.

Each nurse’s station was shielded with transparent plastic shield to prevent interchange of material between nurse’s station (clean zone) and the hallway (intermediate zone)

Zone of ProtectionZone of Protection

biochemical warfare

clear zone inter-zone contamination

Enter with PPE, leaving with Decontamination

Checkpoint Hand washingCheckpoint Hand washing

Before entering/leaving each patient’s room, to prevent any contact transmission from the gloves to the knob, HCWs were required to disinfect their hands.

After entering/leaving the room and door was closed, their hands were again disinfected for protection of the next procedure.

Disinfect-Touch-Disinfect was enforced in all zones.

Traffic into HospitalTraffic into Hospital

Case mix and contact transmission inside ER

A “triage and dispatch” station is located outside the hospitals.

Traffic ControlTraffic Control

Zone of Protection

Checkpoint hand washing

Traffic into Hospital

ResultResult

During the study period, 462 HCWs including 85 physicians, 295 nurses, and 82 administrative personnel and volunteers were clinically evaluated for SARS in study hospitals.

2 nurses contracted SARS, PCR (+)

Using Using Traffic ControlTraffic Control Strategy During Outbreak Strategy During Outbreak Control to Minimize Nosocomial Infection of SARS Control to Minimize Nosocomial Infection of SARS

Among Health-Care WorkersAmong Health-Care Workers

Test Hospital Comparison H Hospitals

Bed A (67) B (18) Total (85) (746)

Suspected 0 (0 %)* 0 (0 %) 0 ( 0%) 43 (5.76 %) Probable 2 (2.98 %) 0 (0 %) 2 (2.35 %) 50 (6.70 %)

Total** 2 (2.98 %) 0 (0 %) 2 (2.35 %) 93 (12.47 %)

* SARS case divided by number of patient bed ** p = 0.004, Chi square, Fisher exact test

Muh-Yong Yen, et al. 2003Muh-Yong Yen, et al. 2003

NPIRPPE

Traffic control

contact

Respiratory

DiscussionDiscussion

Given that PPE and NPIR are tested and available throughout Taiwan, we postulated that PPE and NPIR appear to be unsatisfactory for preventing HCWs from contracting SARS virus if the standard operative procedure was not adherent strictly, which was not unusual in the time of outbreak.

DiscussionDiscussion

We suspect that HCWs especially those of inadequately trained cleaner, part-time workers, may still acquire the SARS virus through inappropriate donning or removal of PPE and accidentally transmitted the virus by hands afterwards.

DiscussionDiscussion

“Traffic Control” differentiates the pathways of patients and the HCWs within the hospital with barriers so that each pathway may not be casually overlapping or crossing, casual contamination will than be blocked.

the integrated checkpoint hand washing spots are mandatory to be accessible throughout the hospital.

DiscussionDiscussion

the checkpoint hand washing within traffic line may strengthen the adherence and to increase frequency of hand washing.

when working in the restricted traffic control area with physical barrier, HCWs/part-time workers will upraise their consciousness to a surroundings of self-control and discipline and to a highest grade infection control standard.

DiscussionDiscussion

our data suggest that probable or suspect SARS case patients may not need to be housed in standard NPIRs for their entire stay.

For stablized patients which indicate that the viral load of contamination is mild.

They may be placed in a step-down regular wards with minor renovation and traffic control instituted.

Using Using Traffic ControlTraffic Control Strategy During Outbreak Strategy During Outbreak Control to Minimize Nosocomial Infection of SARS Control to Minimize Nosocomial Infection of SARS

Among Health-Care WorkersAmong Health-Care Workers

Test Hospital Comparison Hospitals PMH

Bed Total (85) (746) (580)

Total** 2 (2.4 %) 93 (12.5 %) 62 (10.7 %) HCW 0.5 % / 0*** 2.0 %

* SARS case divided by number of patient bed ** p = 0.004, Chi square, Fisher exact test *** SARS hospital ( 松山 三重 )

Muh-Yong Yen, et al. 2003Muh-Yong Yen, et al. 2003

The EndThe End

Thanks for your attention