Therefore, previous thoughts that one smoke plume producing unit was worse than any other should be dismissed and the hazards resulting from the use of both diathermy and laser should be treated as equal.
Having undertaken various research studies involving electrosurgical units, Ott (1993) concluded that there are three main areas for concern with regards staff safety when inhaling the smoke plume. These hazards being, the odour, size of the particulate matter and the smokes potential to contain viable tissues. Two main groups of particulate matter have been identified within the plume; the first of these is biological, consisting of such matter as potentially infectious viruses and bacteria, blood and carbonised tissue. This group of matter itself could be harmful to those in close proximity. The remaining components of plume has been categorised as chemical, containing over 80 various chemicals such as cyanide and acetylene (Kokosa et al1989). A large proportion of these chemicals have been found to hold carcinogenic properties (Hallmo 1991).
No direct link between surgical smoke, aerosol and identifiable cases of infectious diseases has yet been identified. However, with day to day exposure, it is generally accepted that the hazards to the surgical team are increased (Hoglan 1995). If effective evacuation of the small particles and smoke created during surgical procedures is not carried out, the natural dispersion of the particulate matter into the air can result in inhalation. (Wenig et al1993). Hensman et al (1998) state that to date, research has limited its focus to encompassing the potential health risks to personnel within theatre and patients; viruses, viable cells, non-viable particles and hazardous chemicals.
Garden et al (1988) found that throughout one surgical procedure, staff ran the risk of being exposed to a large number of hazards including those of being exposed to live viral DNA and bacterial contaminates. Forming chronic skin irritations and respiratory tract inflammation in the form of bronchitis are a distinct possibility, along with irritation of the nasopharyngeal mucous membranes. All of these factors are linked with the staff sickness levels, which again has an impact on the departmental budget. Whilst concluding a study involving animals, it was found that DNA particulate matter extracted from smoke plume formed when vaporising cattle warts, when injected into host cattle, resulted in the formation of new lesions (Garden et al 1988). Although few formal published studies regarding human safety have been undertaken, it is generally understood that the same reaction would occur (Beebe et al 1993).
To attempt to undertake reduction in any risks that staff members are exposed to, routine risk assessments are undertaken both trust wide and within the department itself.
The topic of risk and risk assessment is one which is unfamiliar to a large proportion of National Health Service staff, although risk assessment is carried out continuously, the processes and outcomes are often masked within daily routines.
Many social theorists have broached the subject of risk with a view to critically analyse the definition of risk. The German sociologist Ulrich Beck is a prime example of this, although speaking in much larger terms than those involving surgical smoke plume; he described the continuing increase in the production of pollutants and corrosives as producing a risk society. (Beck 1992). By this, he meant that the more pollutant substances that are emitted into the atmosphere, the risk of detrimental effects arising from it increase at a parallel rate.
Health care in general emphasises the prevention of disease and the promotion of health (Jones et al 2002). This however is aimed at the health of the general public and is not aimed as intensely at the health of staff members. As Goldman (2004) stated, although risk assessment is a major governing factor throughout the NHS, this in turn is governed partially by budgets and cost implications to individual departments.
Various measures are available within the surgical market which can be put into place to reduce the exposure of staff members to surgical smoke plume and the implied risks involved with this exposure (Brandon et al 1997).
No legal standards are in place in regards to surgical smoke evacuation, only recommendations. Paragraph 7.6 of the Medical Devices Agency (1995) general laser safety advice recommends the use of filtered surgical suction. Also the American National Standards Institute recommend that airborne contaminants should be removed by the use of an efficient filtered evacuation system; they state that this is particularly important where there is a likelihood of viral or carcinogenic particles being present in the surgical smoke plume (ANSI 1988).
Sliney et al (1992) took these recommendations that one step further by stating that a well designed smoke plume evacuator should incorporate a disposable primary filter which removes airborne particles down to 3µm and a second carbon filter which removes odours. Hospital wall and mobile suction units are not suitable for these requirements and therefore must be avoided in the interest of staff safety.
In order to define adequate filtration levels, the Institute of Environmental Sciences have rated filtration systems based on their ability to capture specific size particles at specific efficiencies (Rose 2002). Ultra Low Penetrating Air Filters (ULPA Filters) are utilised within many of the available filtration systems, these ULPA filters have the capability to capture sub micron particles with such efficiency that only one in one million will not be captured during the filtration process (Giordano 1997). The performance of the complete filtration system is dependent on a number of variables, these being, the chosen power setting of the vacuum system, the distance travelled by the evacuated substance between the vacuum and the capture device, the source of the smoke, the diameter of the capture device and the tubing (Rose 2002).
The effectiveness of the filtration systems have been noted to diminish over prolonged usage. The filter itself becomes loaded with the particles that cannot pass through, the demand of the suction unit that provides the power for the filtration then in turn pulls the particles through creating small channels within the filter, rendering the filter totally ineffective (American Health Consultants 1989)
Although the basic idea of surgical smoke evacuation systems is a highly commendable one, the practicality of the systems available is not always as true. An article by American Health Consultants (1989) mentions a few difficulties that arise during the use of evacuation systems that reduce their efficiency, although through no direct fault of the systems themselves, smoke plume is still allowed to be emitted into the atmosphere.
Limited space and access to the source of the surgical smoke increases the risk of some amount of the smoke bypassing the evacuator and entering the surgical atmosphere, to enable the extraction system to run to maximum efficiency the tip of the evacuator should ideally be placed within the shortest possible distance from the source. Also the amount of smoke plume produced has a direct link with the amount allowed into the atmosphere by the limited uptake of the extraction system, if a narrow bore smoke extraction tool is used, smaller amounts of smoke plume could be evacuated than with a larger bore.
During trials within a number of hospitals in the United States, it was found that the noise produced by the smoke extraction units were of a level to cause distraction to the surgeons Liu (1988).
Inhalation of surgical smoke and vapour produced during the process of tissue destruction (electro-cautery) may produce a number of physical symptoms, the most common of which are airway irritation and nausea (Belling et al1997).
The majority of staff members working within the theatre department are under the misconception that surgical face masks provide them with adequate protection from air-borne pathogens such as those found in smoke plume. (Rose 2002). From studies performed by medical researchers such as Chen et al (1992) and Tuomi (1985) it has been concluded that surgical face masks only provide the patient with a degree of protection from droplets produced by the theatre personnel, and provide no protection against the chemical or bacterial hazards found in surgical smoke or aerosols. Furthermore, they found that the already minimal efficiency of the face masks was greatly reduced with prolonged usage.
A more effective mask when requiring protection against surgical smoke plume is a respirator mask. Encompassed within the scope of European Standard EN149, there are three classifications of respirator mask. Those products which meet the third classification provide the better standard of filtration, being effective against 98% of fine test aerosol when tested. Those masks which meet the first and second classifications when tested provided 78% and 92% efficiency respectively (rose 2002). This efficiency however can also be categorised into price ranges, the more efficient the mask, the steeper the price (Paschall 1997).
In conclusion, management primarily have the responsibility of weighing up the cost implications of adequate smoke evacuation systems and staff protection verses the departmental, trust and NHS cost of staff sickness as a result of exposure to surgical smoke plume, and although it may seem dramatic, early retirement of staff on the grounds of ill health due to resulting chronic chest problems.
Sackett et al (1997) say that evidence based practice is regarding the application of current best practice, using external evidence and individuals’ clinical knowledge and expertise. Although there is a limited number of evidence available to show that electrosurgical smoke plume is harmful to staff members, all of the available information recommends that protection against exposure to the hazards of surgical smoke. The information available however, is adequate to encourage staff to question their own individual safety and in turn educate others.
Running concurrently with the clinical governance agenda, smoke evacuation needs to be addressed as a positive change and in such a way as to encourage discussion, education, understanding and most importantly, best quality of care (Hughes & Hughes 2001).
Prior to any major permanent changes being made to daily practices, staff must be educated as to the possible hazards they face through their routine of daily work. This, as with any major change, is a formidable task, however this needs to be undertaken for the health and prolonged working life of today’s theatre staff.
