Contamination of laryngoscope handles

A proposed cleaning classification system for reusable medical devices to complement the Spaulding classification

A central tenet in infection prevention is application of the Spaulding classification system for the safe use of medical devices. Initially defined in the 1950s, this system defines devices and surfaces as being critical, semi-critical or non-critical depending on how they will be used on a patient. Different levels of antimicrobial treatment, defined as various levels of disinfection or sterilization, are deemed appropriate to reduce patient risk of infection. However, a focus on microbial inactivation is insufficient to address this concern, which has been particularly highlighted in routine healthcare facility practices, emphasizing the underappreciated importance of cleaning and achieving acceptable levels of cleanliness. A deeper understanding of microbiology has evolved since the 1950s, which has led to re-evaluation of the Spaulding classification along with a commensurate emphasis on achieving appropriate cleaning. Albeit underappreciated, cleaning has always been important as the presence of residual materials on surfaces can interfere with the efficacy of the antimicrobial process to inactivate micro-organisms, as well as other risks to patients including device damage, malfunction and biocompatibility concerns. Unfortunately, this continues to be relevant, as attested by reports in the literature on the occurrence of device-related infections and outbreaks due to failures in processing expectations. This reflects, in part, increasing sophistication in device features and reuse, along with commensurate manufacturer's instructions for use. Consequently, this constitutes the first description and recommendation of a new cleaning classification system to complement use of the traditional Spaulding definitions to help address these modern-day technical and patient risk challenges. This quantitative risk-based classification system highlights the challenge of efficient cleaning based on the complexity of device features present, as an isolated variable impacting cleaning. This cleaning classification can be used in combination with the Spaulding classification to improve communication of cleaning risk of a reusable medical device between manufacturers and healthcare facilities, and improve established cleaning practices. This new cleaning classification system will also inform future creation, design thinking and commensurate innovations for the sustainable safe reuse of important medical devices.

Reprocessing semicritical items: An overview and an update on the shift from HLD to sterilization for endoscopes

BACKGROUND

Semicritical medical devices are defined as items that come into contact with mucous membranes or nonintact skin (e.g., gastrointestinal endoscopes, endocavitary probes). Such medical devices require minimally high-level disinfection.

METHODS

Analyze the methods used to reprocess semicritical medical devices and identify methods and new technologies to reduce the risk of infection.

RESULTS

The reprocessing methods for semicritical medical devices is described as well as a shift from high-level disinfection to sterilization for lumened endoscopes.

CONCLUSIONS

Strict adherence to current guidelines and transition to sterilization for endoscopes is required as more outbreaks have been linked to inadequately disinfected endoscopes and other semicritical items than any other reusable medical devices.

Reprocessing semicritical items: Outbreaks and current issues

Semicritical medical devices are defined as items that come into contact with mucous membranes or nonintact skin (eg, gastrointestinal endoscopes, endocavitary probes). Such medical devices require minimally high-level disinfection. As many of these items are temperature sensitive, low-temperature chemical methods must be used rather than steam sterilization. Strict adherence to current guidelines is required as more outbreaks have been linked to inadequately cleaned or disinfected endoscopes and other semicritical items than any other reusable medical devices.

Mandated wrapping of airway cart instruments: Limited access without the intended safety benefits

OBJECTIVES/HYPOTHESIS

Isolated case studies have shown improper sterilization or contamination of equipment from anesthesia carts can lead to transmission of disease and even death. Citing this literature, national accrediting agencies mandated all instruments in the otolaryngology airway carts at San Antonio Military Medical Center be packaged to prevent contamination. This study sought to determine the infection and safety implications of packaged airway cart instruments.

STUDY DESIGN

Retrospective chart review.

METHODS

A review of upper aerodigestive tract procedures, some of which penetrated mucosa, was performed by analyzing 100 patient records during the unpackaged period and 100 during the packaged period. A comparison of infections, deaths, and length of stay in the hospital was included in the analysis. Additionally, a timed simulation to setup a simple group of instruments for an emergency airway situation from both the unpackaged and packaged airway carts was performed using a total of 11 surgical technologists and nurses.

RESULTS

Each group had a total of four airway infections and neither had any deaths. The average length of hospital stay was 0.36 days for the unpackaged period and 0.44 days from the packaged period. None of these variables reached statistical significance. The average time to find and set out the correct instruments for the two groups was 46.6 and 95.5 seconds for the unpackaged and packaged airway carts, respectively (P = .004).

CONCLUSIONS

This study suggests individually packaging of instruments used for emergency airway cases may put lives at risk when time matters and fails to decrease the risk of infection.

LEVEL OF EVIDENCE

3 Laryngoscope, 129:715-719, 2019.

Surface contamination in the operating room: use of adenosine triphosphate monitoring

PURPOSE

We prospectively investigated contamination of high-contact surfaces in the operating room (OR) using adenosine triphosphate (ATP) monitoring. We tested whether contamination would increase from morning (AM) to afternoon (PM), despite cleaning between cases. Second, we compared the degree of OR contamination to non-OR control sites.

METHODS

ORs with high case volumes were selected for the study. Ten sites in each OR were swabbed using the AccuPoint^® HC ATP Sanitation Monitoring device, which provided a numerical measure of contamination (relative light units, RLUs). According to the manufacturer, surfaces are considered clean at ≤ 400 RLUs. AM measurements were taken before the start of surgical cases and PM measurements were taken after cases were completed.

RESULTS

Eighty morning and 70 afternoon samples were obtained from 8 ORs. Apart from the OR floor, laryngoscope handles had the highest level of morning contamination (1204 RLUs, interquartile range 345, 2603), with 75% of AM samples and 100% of PM samples exceeding 400 RLUs. This contamination was comparable to hospital toilet seats (87% of samples exceeding 400 RLUs). No sites showed statistically significant increases in contamination from AM to PM.

CONCLUSION

Apart from the OR floors, laryngoscope handles emerged as a key OR site where improved cleaning practices may reduce cross-contamination risk. While some sites showed increased contamination over the course of the day, none of these met statistical significance thereby offering tentative evidence that current cleaning practices during case turnover are effective for most sites.

Pattern of anaesthetic equipment contamination and infection prevention in anaesthesia practice at university hospitals

BACKGROUND AND AIMS

Infection control is essential in anaesthetic practice for both personnel and equipment used. This study aims to evaluate knowledge of anaesthesiologists about infection control practices and to detect the pattern of anaesthetic devices contamination.

METHODS

Cross-sectional observational study at two university hospitals was done. Self-administered questionnaires were distributed to 80 anaesthesiologists and 90 nursing staff. Forty-four samples were taken from rigid laryngoscopes (22 pairs from handle and blade) for detection of bacterial or fungal contamination. Same laryngoscopes were tested for occult blood.

RESULTS

The response rate among the physicians was 72% while for nurses 94.4%. The responses were variable reflecting lack of adequate knowledge and unsatisfactory compliance to infection control practices. Tested samples showed no fungal growth. Fourteen (31.8%) samples were negative for bacteriological contamination and 5/44 (11.4%) showed gram-positive bacilli; gram-positive cocci were isolated from 12 samples (27.3%) where Staphylococcus epidermidis and Staphylococcus aureus, respectively, shared 18.2% and 9.1% of the total samples. Gram-negative bacilli were isolated from 13 samples (29.5%), of which Klebsiella spp. were most frequent (11.4%). Both Pseudomonas aeruginosa and Acinetobacter baumannii were isolated from 6.8% each. Citerobacter spp. was isolated from 4.5%. Occult blood was found in 45.5% of samples.

CONCLUSION

The current study showed contamination of ready-to-use laryngoscopes in operative theatres and ICUs.

Bacterial Contamination and Disinfection Status of Laryngoscopes Stored in Emergency Crash Carts

Objectives

To identify bacterial contamination rates of laryngoscope blades and handles stored in emergency crash carts by hospital and area according to the frequency of intubation attempts.

Methods

One hundred forty-eight handles and 71 blades deemed ready for patient use from two tertiary hospitals were sampled with sterile swabs using a standardized rolling technique. Samples were considered negative (not contaminated) if no colonies were present on the blood agar plate after an 18-hour incubation period. Samples were stratified by hospital and according to the frequency of intubation attempts (10 attempts per year) using the χ²-test and Fisher exact test.

Results

One or more species of bacteria were isolated from 4 (5.6%) handle tops, 20 (28.2%) handles with knurled surfaces, and 27 (18.2%) blades. No significant differences were found in microbial contamination levels on the handle tops and blades between the two hospitals and two areas according to the frequency of intubation attempts. However, significant differences were found between the two hospitals and two areas in the level of microbial contamination on the handles with knurled surfaces (p<0.05).

Conclusions

Protocols and policies must be reviewed to standardize procedures to clean and disinfect laryngoscope blades and handles; handles should be re-designed to eliminate points of contact with the blade; and single-use, one-piece laryngoscopes should be introduced.

Comparison of efficacy and cost-effectiveness of 0.55% ortho-phthalaldehyde and 2% glutaraldehyde for disinfection of laryngoscopes: A prospective pilot study

BACKGROUND AND AIMS

The laryngoscope is a potential source of cross-infection as it involves contact with the mucous membrane, saliva and occasionally blood. This study compared efficacy and cost-effectiveness of two Centre for Disease Control approved agents for disinfection of laryngoscope blades.

METHODS

One hundred and sixty patients requiring laryngoscopy and intubation for general anaesthesia were randomly allocated into two groups. After tracheal intubation, used laryngoscope blades were cleaned with tap water. The blades were then immersed in either 2% w/v glutaraldehyde for a contact time of 20 min or 0.55% w/v ortho-phthalaldehyde (OPA) for 10 min. The handles were wiped with 0.5% w/v chlorhexidine wipes. Samples were collected using sterile cotton swabs from the tip, flange and light bulb area of the laryngoscope blade and one from the handle. They were cultured aerobically on blood and McConkey agar.

RESULTS

In 2% glutaraldehyde group, of 240 samples sent from the blades, 2 (0.8%) showed the growth of methicillin-resistant coagulase-negative staphylococci (MRCONS) and Enterobacter. In OPA group, of 240 samples, 2 (0.8%) showed growth of MRCONS. Thus, 2% glutaraldehyde and 0.55% OPA were comparable in terms of efficacy of disinfection. Growth was seen on 4 out of 160 handles.

CONCLUSIONS

We suggest OPA for high-level disinfection of laryngoscope blades as it is equally efficacious as compared to glutaraldehyde, with a shorter contact time and available as a ready to use formulation.

Disinfection and Sterilization in Health Care Facilities: An Overview and Current Issues

When properly used, disinfection and sterilization can ensure the safe use of invasive and noninvasive medical devices. The method of disinfection and sterilization depends on the intended use of the medical device: critical items (contact sterile tissue) must be sterilized before use; semicritical items (contact mucous membranes or nonintact skin) must be high-level disinfected; and noncritical items (contact intact skin) should receive low-level disinfection. Cleaning should always precede high-level disinfection and sterilization. Current disinfection and sterilization guidelines must be strictly followed.

Reprocessing semicritical items: Current issues and new technologies

Semicritical medical devices are defined as items that come into contact with mucous membranes or nonintact skin (eg, gastrointestinal endoscopes, endocavitary probes). Such medical devices minimally require high-level disinfection. Because many of these items are temperature sensitive, low-temperature chemical methods are usually used rather than steam sterilization. Strict adherence to current guidelines is required because more outbreaks have been linked to inadequately cleaned or disinfected endoscopes and other semicritical items undergoing high-level disinfection than any other reusable medical device.

Disinfection of transvaginal ultrasound probes in a clinical setting: comparative performance of automated and manual reprocessing methods

OBJECTIVES

Transvaginal and intracavitary ultrasound probes are a possible source of cross-contamination with microorganisms and thus a risk to patients' health. Therefore appropriate methods for reprocessing are needed. This study was designed to compare the standard disinfection method for transvaginal ultrasound probes in Germany with an automated disinfection method in a clinical setting.

METHODS

This was a prospective randomized controlled clinical study of two groups. In each group, 120 microbial samples were collected from ultrasound transducers before and after disinfection with either an automated method (Trophon EPR®) or a manual method (Mikrozid Sensitive® wipes). Samples were then analyzed for microbial growth and isolates were identified to species level.

RESULTS

Automated disinfection had a statistically significantly higher success rate of 91.4% (106/116) compared with 78.8% (89/113) for manual disinfection (P = 0.009). The risk of contamination was increased by 2.9-fold when disinfection was performed manually (odds ratio, 2.9 (95% CI, 1.3-6.3)). Before disinfection, bacterial contamination was observed on 98.8% of probes. Microbial analysis revealed 36 different species of bacteria, including skin and environmental bacteria as well as pathogenic bacteria such as Staphylococcus aureus, enterobacteriaceae and Pseudomonas spp.

CONCLUSIONS

Considering the high number of contaminated probes and bacterial species found, disinfection of the ultrasound probe's body and handle should be performed after each use to decrease the risk of cross-contamination. This study favored automated disinfection owing to its significantly higher efficacy compared with a manual method. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Laryngoscope decontamination techniques: A survey

Background and Aims:

India is a vast country with variable, nonuniform healthcare practices. A laryngoscope is an important tool during general anesthesia and resuscitation. The study aimed to determine the current practices of laryngoscope decontamination in India.

Material and Methods:

An online survey was conducted amongst 100 anesthesiologists to determine the common methods of laryngoscope decontamination adopted in their settings. The survey was done over 6 months after validating the questionnaire.

Results:

A total of 73 responses were received out of 100. The result of the survey revealed that there is no uniform technique of laryngoscope decontamination. There is marked variability in techniques followed not only among different institutions, but also within the same institution.

Conclusion:

There are no fixed protocols adopted for laryngoscope decontamination. Thus, there is a need to develop definitive guidelines on this subject, which can be implemented in India.

A New Approach to Pathogen Containment in the Operating Room: Sheathing the Laryngoscope After Intubation

BACKGROUND

Anesthesiologists may contribute to postoperative infections by means of the transmission of blood and pathogens to the patient and the environment in the operating room (OR). Our primary aims were to determine whether contamination of the IV hub, the anesthesia work area, and the patient could be reduced after induction of anesthesia by removing the risk associated with contaminants on the laryngoscope handle and blade. Therefore, we conducted a study in a simulated OR where some of the participants sheathed the laryngoscope handle and blade in a glove immediately after it was used to perform an endotracheal intubation.

METHODS

Forty-five anesthesiology residents (postgraduate year 2-4) were enrolled in a study consisting of identical simulation sessions. On entry to the simulated OR, the residents were asked to perform an anesthetic, including induction and endotracheal intubation timed to approximately 6 minutes. Of the 45 simulation sessions, 15 were with a control group conducted with the intubating resident wearing single gloves, 15 with the intubating resident using double gloves with the outer pair removed and discarded after verified intubation, and 15 wearing double gloves and sheathing the laryngoscope in one of the outer gloves after intubation. Before the start of the scenario, the lips and inside of the mouth of the mannequin were coated with a fluorescent marking gel. After each of the 45 simulations, an observer examined the OR using an ultraviolet light to determine the presence of fluorescence on 25 sites: 7 on the patient and 18 in the anesthesia environment.

RESULTS

Of the 7 sites on the patient, ultraviolet light detected contamination on an average of 5.7 (95% confidence interval, 4.4-7.2) sites under the single-glove condition, 2.1 (1.5-3.1) sites with double gloves, and 0.4 (0.2-1.0) sites with double gloves with sheathing. All 3 conditions were significantly different from one another at P < 0.001. Of the 18 environmental sites, ultraviolet light detected fluorescence on an average of 13.2 (95% confidence interval, 11.3-15.6) sites under the single-glove condition, 3.5 (2.6-4.7) with double gloves, and 0.5 (0.2-1.0) with double gloves with sheathing. Again, all 3 conditions were significantly different from one another at P < 0.001.

CONCLUSIONS

The results of this study suggest that when an anesthesiologist in a simulated OR sheaths the laryngoscope immediately after endotracheal intubation, contamination of the IV hub, patient, and intraoperative environment is significantly reduced.

[Disinfection and recontamination of rigid endoscopes: improved safety using an immersion quiver system]

BACKGROUND

In Otorhinolaryngology, rigid endoscopes are used daily at a high frequency. There is no consensus for reprocessing these medical instruments. Often immersion disinfection procedures are used. The present study examined the possible risk of recontamination by this disinfection method and investigated the possibility of avoiding this risk by using a new immersion quiver system.

METHODS

Using coloured markers, a possible contact of the endoscope with the top edges of quivers of different diameters during endoscope removal was tested for. In addition, it was evaluated whether Staphylococcus aureus transfer is possible via this route. The same methodology was applied to a new immersion quiver system.

RESULTS

Whenever removing the rigid endoscopes from the conventional quiver, these touched the top of the quiver, regardless of its diameter. A transfer of Staphylococcus aureus from the quiver to the endoscope via this route could be detected in five out of eight attempts. During endoscope removal from the new immersion quiver system, no contact of the endoscope with the outer quiver occurred in 20 passes. In none of eight trials was a transfer of Staphylococcus aureus from previously contaminated immersion quivers to the endoscope shown; all immersion quivers were sterile after disinfection.

DISCUSSION

After conventional immersion disinfection, recontamination of rigid endoscopes by a contaminated quiver edge is possible. An immersion quiver system can resolve this risk of recontamination easily, by decontaminating not only the endoscope, but also the immersion quiver (inner quiver) itself in the disinfectant solution.

Double gloves: a randomized trial to evaluate a simple strategy to reduce contamination in the operating room

BACKGROUND

Oral flora, blood-borne pathogens, and bacterial contamination pose a direct risk of infection to patients and health care workers. We conducted a study in a simulated operating room using a newly validated technology to determine whether the use of 2 sets of gloves, with the outer set removed immediately after endotracheal intubation, may reduce this risk.

METHODS

Forty-one anesthesiology residents (PGY 2-4) were enrolled in a study consisting of individual or group simulation sessions. On entry to the simulated operating room, the residents were asked to perform an anesthetic induction and tracheal intubation timed to approximately 6 minutes; they were unaware of the study design. Of the 22 simulation sessions, 11 were conducted with the intubating resident wearing single gloves, and 11 with the intubating resident using double gloves with the outer pair removed after verified intubation. Before the start of the scenario, we coated the lips and inside of the mouth of the mannequin with a fluorescent marking gel as a surrogate pathogen. After the simulation, an observer examined 40 different sites using a handheld ultraviolet light in the operating room to determine the transfer of surrogate pathogens to the patient and the patient's environment. Residents who wore double gloves were instructed by a confederate nurse to remove the outer set immediately after completion of the intubation. Forty sites of potential intraoperative pathogen spread were identified and assigned a score.

RESULTS

The difference in the rate of contamination between anesthesiology residents who wore single gloves versus those with double gloves was clinically and statistically significant. The number of sites that were contaminated in the operating room when the intubating resident wore single gloves was 20.3 ± 1.4 (mean ± SE); the number of contaminated sites when residents wore double gloves was 5.0 ± 0.7 (P < 0.001).

CONCLUSIONS

The results of this study suggest that when an anesthesiologist wears 2 sets of gloves during laryngoscopy and intubation and then removes the outer set immediately after intubation, the contamination of the intraoperative environment is dramatically reduced.

Chlorhexidine to maintain cleanliness of laryngoscope handles: an audit and laboratory study

CONTEXT

Laryngoscope handles are a potential vector for infection transmission and require adequate decontamination.

OBJECTIVE

To establish an effective cleaning regimen for laryngoscope handles.

DESIGN

Three laboratory studies and an audit cycle.

SETTING

The Queen Elizabeth Hospital, King's Lynn, UK.

MATERIALS

Twenty Heine laryngoscope handles.

INTERVENTIONS

Twenty laryngoscope handles were contaminated with microbial broth and then disinfected with chemical wipes, either using Sani-Cloth CHG 2% (chlorhexidine 2%/alcohol 70%) or Tuffie 5 wipes. This was repeated with an interval of 24 h between cleaning and contamination. A further experiment repeatedly re-contaminated the handles at varying time intervals after cleaning. The audit established the current level of contamination of laryngoscope handles within the hospital, and this was repeated following a change in cleaning protocol.

MAIN OUTCOME MEASURES

Bacterial growth on agar plates was counted as the number of colony forming units.

RESULTS

Both Sani-Cloth CHG 2% and Tuffie 5 wipes were effective against microorganisms, including methicillin-resistant Staphylococcus aureus, immediately following wiping (P = 0.002). However, the chlorhexidine wipes also had a residual effect such that after wiping, the handle remained sterile following further contamination and this effect persisted for 24 h. Audit following the introduction of this practice showed significant improvements in the incidence and extent of contamination compared with the previous disinfection practice (P<0.002).

CONCLUSION

Decontamination with Sani-Cloth CHG 2% wipes confers additional advantages over routine autoclaving or handle disposal, due to a residual effect. Autoclaving handles may be desirable on a scheduled basis and if Clostridium difficile is encountered.

New developments in reprocessing semicritical items

Semicritical medical devices are defined as items that come into contact with mucous membranes or nonintact skin (eg, gastrointestinal endoscopes). Such medical devices require minimally high-level disinfection. Because many of these items are temperature sensitive, low-temperature chemical methods must be used rather than steam sterilization. Strict adherence to current guidelines is required because more outbreaks have been linked to inadequately cleaned or disinfected endoscopes undergoing high-level disinfection than any other medical device.