Bacterial Contamination of Ultrasound and Stethoscope Surfaces in Low- and High-Resource Settings

ESICM-ESPNIC international expert consensus on quantitative lung ultrasound in intensive care

PURPOSE

To provide an international expert consensus on technical aspects and clinical applications of quantitative lung ultrasound in adult, paediatric and neonatal intensive care.

METHODS

The European Society of Intensive Care (ESICM) and the European Society of Paediatric and Neonatal Intensive Care (ESPNIC) endorsed the project. We selected an international panel of 20 adult, paediatric and neonatal intensive care experts with clinical and research expertise in quantitative lung ultrasound, plus two non-voting methodologists. Fourteen clinical questions were proposed by the chairs to the panel, who voted for their priority (1-9 Likert-type scale) and proposed modifications/supplementing (two-round vote). All the questions achieved the predefined threshold (mean score > 5) and 14 groups of 3 mixed adult/paediatric experts were identified to develop the statements for each clinical question; predefined groups of experts in the fields of adult and paediatric/neonatal intensive care voted statements specific for these subgroups. An iterative approach was used to obtain the final consensus statements (two-round vote, 1-9 Likert-type scale); statements were classified as with agreement (range 7-9), uncertainty (4-6), disagreement (1-3) when the median score and ≥ 75% of votes laid within a specific range.

RESULTS

A total of 46 statements were produced (4 adults-only, 4 paediatric/neonatal-only, 38 interdisciplinary); all obtained agreement. This result was also achieved by acknowledging in the statements the current limitations of quantitative lung ultrasound.

CONCLUSION

This consensus guides the use of quantitative lung ultrasound in adult, paediatric and neonatal intensive care and helps identify the fields where further research will be needed in the future.

Bacterial contamination of ultrasound probes in emergency departments: A multicentre observational study

BACKGROUND

Ultrasound is frequently used in emergency departments (ED) for patient evaluation and diagnosis. Despite the risk of probe contamination from body fluids and blood, the rate of such contamination remains unclear.

AIM

This study aimed to evaluate bacterial contamination of ultrasound probes in EDs, focusing on hospital types and reprocessing methods.

METHODS

A multicentre prospective observational study was conducted at a university hospital, a non-academic tertiary hospital, and a regional hospital in 2023. Samples were collected from probes used on ED patients. Reprocessing methods included water-moistened wipes alone, water-moistened wipes with ethanol wipes, quaternary ammonium wipes alone, and quaternary ammonium wipes with ethanol or hypochlorite wipes. Outcomes included the level of bacterial contamination, measured by colony-forming units (CFU) per total surface area of each probe, and resistant bacterial strains.

FINDINGS

The median CFU was 10 (IQR: 0-50) at the university hospital, 40 (10-135) at the non-academic tertiary hospital, and 30 (1-95) at the regional hospital. By reprocessing method, the median CFU was 20 (1-90) for water-moistened wipes alone, 10 (0-20) for water-moistened wipes and additional ethanol wipe, 90 (40-180) for quaternary ammonium wipes alone, and 20 (1-50) for quaternary ammonium wipe and additional ethanol or hypochlorite wipe. Resistant bacterial strains were found on 18.2% of probes.

CONCLUSION

High levels of bacterial contamination, including resistant strains, were observed on ultrasound probes in EDs, regardless of facility type and reprocessing method.

CLINICAL TRIAL NUMBER

Not applicable.

Optimizing Ultrasound Probe Disinfection for Healthcare-Associated Infection Control: A Comparative Analysis of Disinfectant Efficacy

Background/Aims: Ultrasound is a key diagnostic tool in modern medicine due to its ability to provide real-time, high-resolution images of the internal structures of the human body. Despite its undeniable advantages, there are challenges related to the contamination of ultrasound probes, with the risk of healthcare-associated infections. The aim of this review was to identify the most effective disinfectants for disinfecting ultrasound probes to prevent the transmission of pathogens between patients. Methods: A narrative review was conducted using the PubMed, CINAHL, Embase, and Cochrane Library databases, resulting in the inclusion of 16 studies from an initial 1202 records. Results: Hydrogen peroxide (H2O2) was the most effective disinfectant, especially in automated systems, achieving a >5-log10 reduction in viral load, including that of resistant pathogens like Human Papillomavirus. Chlorhexidine gluconate (4%) demonstrated strong antibacterial efficacy, eliminating 84.62% of bacterial contamination, but was less effective against viral pathogens. Glutaraldehyde was effective in some cases, though its use carried a higher risk of probe damage. The use of sodium hypochlorite varied across guidelines; some endorsed it for COVID-19 prevention, while others cautioned against its application due to potential probe damage. Conclusions: This study highlights the importance of advanced disinfection technologies and strict adherence to protocols in improving infection control. Automated systems utilizing H2O2 strike an ideal balance between antimicrobial efficacy and equipment preservation. Future research should focus on developing disinfection methods that prioritize safety, cost-effectiveness, and environmental sustainability in various clinical environments.

Monitoring of pulmonary involvement in critically ill COVID-19 patients - should lung ultrasound be preferred over CT?

BACKGROUND

It is unclear if relevant changes in pulmonary involvement in critically ill COVID-19 patients can be reliably detected by the CT severity score (CTSS) and lung ultrasound score (LUSS), or if these changes have prognostic implications. In addition, it has been argued that adding pleural abnormalities to the LUSS could improve its prognostic value. The objective of this study was to compare LUSS and CTSS for the monitoring of COVID-19 pulmonary involvement through: first, establishing the correlation of LUSS (± pleural abnormalities) and CTSS throughout admission; second, assessing agreement and measurement error between raters for LUSS, pleural abnormalities, and CTSS; third, evaluating the association of the LUSS (± pleural abnormalities) and CTSS with mortality at different timepoints.

METHODS

This is a prospective, observational study, conducted during the second COVID-19 wave at the AmsterdamUMC, location VUmc. Adult COVID-19 ICU patients were prospectively included when a CT or a 12-zone LUS was performed at admission or at weekly intervals according to local protocol. Patients were followed 90 days or until death. We calculated the: (1) Correlation of the LUSS (± pleural abnormalities) and CTSS throughout admission with mixed models; (2) Intra-class correlation coefficients (ICCs) and smallest detectable changes (SDCs) between raters; (3) Association between the LUSS (± pleural abnormalities) and CTSS with mixed models.

RESULTS

82 consecutive patients were included. Correlation between LUSS and CTSS was 0.45 (95% CI 0.31-0.59). ICCs for LUSS, pleural abnormalities, and CTSS were 0.88 (95% CI 0.73-0.95), 0.94 (95% CI 0.90-0.96), and 0.84 (95% CI 0.65-0.93), with SDCs of 4.8, 1.4, and 3.9. The LUSS was associated with mortality in week 2, with a score difference between patients who survived or died greater than its SDC. Addition of pleural abnormalities was not beneficial. The CTSS was associated with mortality only in week 1, but with a score difference less than its SDC.

CONCLUSIONS

LUSS correlated with CTSS throughout ICU admission but performed similar or better at agreement between raters and mortality prognostication. Given the benefits of LUS over CT, it should be preferred as initial monitoring tool.