Applying the Hierarchy of Controls: What Occupational Safety Can Teach us About Safely Navigating the Next Phase of the Global COVID-19 Pandemic

Eighteen months into the COVID-19 pandemic, and as the world struggles with global vaccine equity, emerging variants, and the reality that eradication is years away at soonest, we add to notion of “layered defenses” proposing a conceptual model for better understanding the differential applicability and effectiveness of precautions against SARS-CoV-2 transmission. The prevailing adaptation of Reason's Swiss cheese model conceives of all defensive layers as equally protective, when in reality some are more effective than others. Adapting the hierarchy of controls framework from occupational safety provides a better framework for understanding the relative benefit of different hazard control strategies to minimize the spread of SARS-CoV-2.

774. Outbreak of Central-Line-Associated Bloodstream Infections (CLABSI) amid the COVID-19 Pandemic Associated with Changes in Central Line Dressing Care Accompanying Changes in Nursing Education, Nursing Documentation, and Dressing Supply Kits

Background National Healthcare Safety Network (NHSN) data have revealed an increase in CLABSI associated with the COVID-19 pandemic, but data on factors mediating the increase are limited. Our hospital had been free of CLABSI for 18 months, but we encountered an outbreak of 7 CLABSI over a 5-month period beginning in November 2020. This led to an investigation that revealed that some underlying issues were related to COVID-19. Methods Infection prevention staff at Omaha’s Veterans Affairs Medical Center interviewed hospital staff and performed a retrospective chart review of patients with CLABSI (based on the NHSN definition) amid the COVID-19 pandemic. Results The first case of CLABSI in the outbreak was detected in November 2020. Prior to that, there was no case of CLABSI since April 2019, as shown in the graph. Each case of CLABSI was associated with a different microorganism. Further investigation revealed deviations from our usual practices in central line dressing care. Our response to COVID-19 had included alterations in periodic competency training (including dressing care) for nursing staff as well as the rapid introduction of streamlined inpatient nursing documentation. Previously, dressing kits included chlorhexidine-impregnated dressings; in November, a kit without these dressings was introduced. A weekly audit of dressing care was begun in March 2021. No CLABSI was identified in April 2021. Types of Microorganisms identified Different types of microorganisms isolated during the CLABSI outbreak each month. The trend of CLABSI in VA Nebraska-Western Iowa Health Care System Conclusion We encountered a CLABSI outbreak associated with deviations from usual central line dressing care. Using the concept of the Swiss cheese model of error prevention, we recognized alterations in three barriers: competency training; thorough documentation; and complete supply kits. The first two of these factors were directly related to our COVID-19 response. Our findings illustrate the relevance of the Swiss cheese model for maintaining a safe healthcare environment. Disclosures Marvin J. Bittner, MD, Merck (Advisor or Review Panel member)Sanofi Pasteur (Speaker's Bureau)

Swiss Cheese

Swiss Cheese famously has holes, which can represent the holes and oversights that lead to harm. The Swiss Cheese Model has become a powerful way to help think more clearly about errors and harm.

Tuberculosis in times of COVID-19

The COVID-19 pandemic has caused widespread disruptions to tuberculosis (TB) care and service delivery in 2020, setting back progress in the fight against TB by several years. As newer COVID-19 variants continue to devastate many low and middle-income countries in 2021, the extent of this setback is likely to increase. Despite these challenges, the TB community can draw on the comprehensive approaches used to manage COVID-19 to help restore progress and mitigate the impact of COVID-19 on TB. Our team developed the ‘Swiss Cheese Model for Ending TB’ to illustrate that it is only through multisectoral collaborations that address the personal, societal and health system layers of care that we will end TB. In this paper, we examine how COVID-19 has impacted the different layers of TB care presented in the model and explore how we can leverage some of the lessons and outcomes of the COVID-19 pandemic to strengthen the global TB response.

The Impact of the Adjunct Heat-Treated Starter Culture and Lb. helveticus LH-B01 on the Proteolysis and ACE Inhibitory Activity in Dutch-Type Cheese Model during Ripening

Adjunct cultures are used in cheesemaking to improve the sensory characteristics of the ripened cheeses. In addition, it is known that different adjunct cultures are capable of producing enzymes with the specificity to hydrolyze caseins, leading to the release of various bioactive compounds (bioactive peptides, amino acids, etc.). The objective of this study was to evaluate the effect of adjunct heat-treated starter XT–312 and a cheese culture Lb. helveticus LH-B01 on the proteolytic activity and angiotensin converting enzymes inhibitors (ACE) in cheese models during ripening. Seven different cheese models were evaluated for: proteolytic activity using the spectrophotometric method with ortho-phthaldialdehyde (OPA), soluble nitrogen (SN), trichloroacetic acid-soluble nitrogen (TCA-SN) phosphotungstic acid-soluble nitrogen (PTA-SN), total nitrogen (TN), pH, contents of water, fat, as well as for total bacteria count (TBC), count of Lactococcus genus bacteria, count of Lb. helveticus, and number of non-starter lactic acid bacteria (NSLAB). Presence of adjunct bacterial cultures both in the form of a cheese culture LH-B01 and heat-treated XT–312 starter promoted primary and secondary proteolysis, which resulted in acceleration of the ripening process. ACE inhibitory activity and proteolytic activity was the highest throughout of ripening for cheese model with LH-B01 culture. The cheese models with the adjunct heat-treated starter were characterized by lower TBC, NSLAB and lower count of Lactococcus genus bacteria during ripening, compared to control cheeses.

Analyzing the cause of human electrical accidents using Swiss Cheese model

Purpose This study aims to explore the factors influencing electrical accidents. Here, the authors aim to understand and model the causes of electrical accidents at multiple levels. Design/methodology/approach In the study, the authors have tried to put causes of accidents in the electricity distribution segment, in the framework of the Swiss Cheese model. Delphi kind of expert survey was conducted to find the Cheese Slice (level) and the causes (holes) for electrical accidents. Inputs from a hundred experts having more than five years of experience in electrical utility companies have been used to find Cheese Slice and holes, to explain the occurrence of an electrical accident. Findings Effective training for safe work practices, safe knowledge and closer supervision would go a long way to plug the holes in the Cheese Slice in human factors. The difference in perception of managers, supervisors and workers on the importance of various causes of electrical accidents are also presented and discussed. Research limitations/implications This research is based on expert opinion and survey where respondent perception is reported. Actual accident data has not been used here. Practical implications The holes or causes of accidents at different levels (Cheese Slice) have been identified for plugging or removal for better safety. Social implications Electrical energy is widely used, and therefore, electrical safety is a social concern and also improving it is a social need. Originality/value The study contributes to electrical safety issues in the electrical utility sector.