Cochrane Canada 9th Annual Symposium February 2011 - PowerPoint PPT Presentation

Surgical smokes in the operating theatre

Using best evidence for health risk assessment

Marc Rhainds, M.D., M.Sc., FRCPC

Mélanie Hamel, Ph.D

Martin Coulombe, D.A.A., M.Sc., MAP

Cochrane Canada 9th

Annual SymposiumFebruary 2011

CHUQ

Centre hospitalier universitaire de Québec

• CHUQ: Leader in research and technology assessment
• 3 hospitals
• 1,063 beds
• 535,887 users
• 8,880 staff; 1,051 physicians
• Annual budget: > 625M$

http://www.chuq.qc.ca

UETMIS (implemented in 2006)

Health Technology Assessment Unit

Health Technology Assessment (HTA)

• Introducing new technologies can be challenging for healthcare decision makers
• Maximize health benefits
• Risks minimization
• Cost-effectiveness
• Evidence-based information is required
• HTA is helpful to support decisions at the hospital level

Objectives

• To assess the health risks associated with surgical smokes exposure
• Using this example :
• To discuss how to manage uncertainty in the evidence-based decision making

It is suggested that surgical smokes produced during surgical procedures may be harmful for healthcare professionals

• Advertising: Surgical smoke = health hazard for the staff
• Healthcare professionals in the CHUQ want to have portable smoke evacuators devices
• But is there a real risk ?

www.filtechenterprise.com

www.aorn.org

www.users.qwest.net

Risk Assessment

• Biological risks
• Malignant cells
• Bacteria
• Virus

Objective

To assess health risks associated with occupational exposure to surgical smokes

• Chemical risks
• Volatile organic compounds
• Carbon monoxide
• Particulate matters

• Nuisance phenomena
• Surgical smoke:odour, obstructed vision, eye and throat irritation
• Device: Noise

Inclusion criteria

• Various surgeries
• All electrocautery devices

Until June 2010

• Systematic reviews
• Randomized controlled trials
• Experimental studies

• Pubmed
• Cochrane Library
• Grey literature

Limits

• Human & animal
• English and French

• Article selection, quality assessment, data extraction and synthesis  One reviewer
• Appraisal  Three reviewers
• Synthesis review  Expert groups

• One systematic review was found (Burrows, 2000)
• Centre for Clinical Effectiveness (CCE), Australia
• Request: Is smoke plume from laser / electric surgical procedures a health hazard?
• Based on two expert consensus
• Author’s conclusion: “A critical appraisal of the evidence for this question was not therefore undertaken.” (level IV evidence)
• No RCT assessing health risks associated with surgical smoke exposure was found.
• There is no data available regarding asthma, respiratory symptoms prevalence in surgical staff exposed to surgical smokes

Should we stop at this point?

• How do we help healthcare decision makers?

• Results from experimental studies show that surgical smoke may contain malignant cells, bacteria and virus
• However, viability of cells in the surgical smokes and the potential of communicable diseases to healthcare professionals remain unclear

• Data from experimental / environmental studies were compared to occupational health and safety standards

Volatile organic compounds (VOCs) and carbon monoxide (CO)

• ACGIH : American Conference of Governmental Industrial Hygienists
• IRRST : Institut de recherche Robert-Sauvé en santé et en sécurité du travail
• NIOSH : National Institute for Occupational Safety and Health
• WHO : World health organization
• OSHA : Occupational Safety and Health Administration

Particulate matters (PM)

• WHO : World health organization
• US EPA : US Environmental Protection Agency

Volatile organic compounds (VOCs),

• carbon monoxide (CO) and particulate matters (PM)

TWA: Time weighted average

• Data from surgical smokes analysis, measured in the breathing zone and the operating room, suggest that ambient air concentrations of CO, VOCs, and PM are very low and far below the occupational exposure limits (TWA, 8 hours / day, 5 days/ week).

Nuisance phenomena

According to NIOSH:

• Various symptoms are reported by surgical staff after exposure to surgical smokes:
• Headache, eyes, nose and throat irritations, obstructed vision, unpleasant odours
• Noise pollution caused by the suction of smoke outlets
• We did not find any evaluation of the nuisance phenomena

Organizationrecommendations

Although there is no clear evidence that surgical smoke may represent health hazard, many governmental organizations and professional health associations have recommended:

• Individual protection measures
• Smoke evacuation in the operating theatre
• Use of portable evacuation and filtration systems:
• To decrease the concentration of airborne pathogens in a room;
• When the HVAC system cannot meet building ventilation rate requirements;
• For applications which require higher flows;
• When the type of pathogen and transmission mode is not yet known.

Risk management considerations

General ventilation in operating rooms systems (HVAC)

• Usually sufficient to remove fumes (COSSH, England)

Smoke filtration effectiveness

• Limited ability for some particles (aerosols, particles of large size)
• Limited effectiveness for high-capacity filters (HEPA filter)
• Reduced distance between the suction nozzle and the source could increase the efficiency

• Perceived health risks > real risks
• Effectiveness of HVAC systems in operating rooms is not uniform between the three hospitals
• Beyond the biological and chemical risks: should health decision making be driven by the nuisance phenomena (odor, irritation)related to surgical smoke?
• Disadvantages associated with the use of portable smoke evactuators
• Noise
• Interference in the communication between members of the surgical team
• Size of smoke evacuators in limited space
• Device maintenance: staff formation and costs

• When there is no systematic review and no RCT available, what should local HTA units do to support decision making?
• Doing nothing appears not an option!
• In this example of the assessment of health risks associated with surgical smokes exposure,

1) we looked at data associated with a weak level of evidence:

• Experimental studies (e.g. environmental sampling and analysis)
• Expert consensus and judgment
• Occupational standards (chemical exposure limits)

2) we had face-to-face meetings with strategic committees of managers and clinicians to discuss the data available and enhance knowledge translation

• Use of other data than RCT to answer questions of efficacy and effectiveness, are we lowering the bar?
• Are we overweighting local evidence just because it is local?
• Are we overweighting our own evidence because we paid for it?
• Opportunities for field evaluation

• In this example, adapting of HTA processes was helpful to support the decision making with the best available evidence.
• CHUQ decisions :
• Positive reception from decision makers
• No systematic use of portable system is expected in the CHUQ
• Use of portable evacuation and filtration system restricted to specific type of surgeries (e.g. breast)
• Publication of a report : March 2011

Thank you !