System for open-chest, multidirectional electrical defibrillation

Abstract Background Post-surgical infections due to Mycobacterium chimaera appeared as a novel nosocomial threat in 2015, with a worldwide outbreak due to contaminated heater-cooler units used in open chest surgery. We report the results of investigations conducted in France including whole genome sequencing comparison of patient and HCU isolates. Methods We sought M. chimaera infection cases from 2010 onwards through national epidemiological investigations in healthcare facilities performing cardiopulmonary bypass together with a survey on good practices and systematic heater-cooler unit microbial analyses. Clinical and HCU isolates were subjected to whole genome sequencing analyzed with regards to the reference outbreak strain Zuerich-1. Results Only two clinical cases were shown to be related to the outbreak, although 23% (41/175) heater-cooler units were declared positive for M. avium complex. Specific measures to prevent infection were applied in 89% (50/56) healthcare facilities although only 14% (8/56) of them followed the manufacturer maintenance recommendations. Whole genome sequencing comparison showed that the clinical isolates and 72% (26/36) of heater-cooler unit isolates belonged to the epidemic cluster. Within clinical isolates, 5 to 9 non-synonymous single nucleotide polymorphisms were observed, among which an in vivo mutation in a putative efflux pump gene observed in a clinical isolate obtained for one patient under antimicrobial treatment. Conclusions Cases of post-surgical M. chimaera infections were declared to be rare in France, although heater-cooler units were contaminated as in other countries. Genomic analyses confirmed the connection to the outbreak and identified specific single nucleotide polymorphisms, including one suggesting fitness evolution in vivo.

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Surveillance and control of M. chimaera infections in the Tuscany Region, Italy

European Journal of Public Health ◽

10.1093/eurpub/ckaa166.705 ◽

2020 ◽

Vol 30 (Supplement_5) ◽

Author(s):

B Casini ◽

B Tuvo ◽

M Totaro ◽

A Baggiani ◽

G Privitera

Keyword(s):

Cardiac Surgery ◽

Cardiopulmonary Bypass ◽

Water Sample ◽

Case Finding ◽

Microbial Count ◽

Clinical Specimens ◽

Open Chest ◽

Microbiological Parameters ◽

History Of ◽

And Control

Abstract Background Disseminated M. chimaera infections among patients who underwent open-chest surgery with cardiopulmonary bypass have been associated with the contamination of heater-cooler devices (HCDs). The Tuscany region in the Decree 3822/2019 issued recommendations for the surveillance and control of M. chimaera infections. Methods In three Tuscan cardiac surgery centers, the case finding was carried out through evaluation and testing of patients with a history of HCD exposure (past 6 years) was performed. Water and aerosol samples were analyzed from each HCDs to determine the microbiological parameters required by the Directive 98/83/CE and to assess the presence of non-tuberculous mycobacteria (NTMs), according to the regional protocol. Results M. chimaera infection was not found in any patient and all clinical specimens tested negative. 22 HCDs were sampled (n.12 LivaNova, n.1 Terumo and n.9 Maquet) for a total of 114 samples (45, 8, 2 and 59 respectively). All the microbiological parameters were compliant, excepted for total microbial count at 36 °C that exceeded 100 CFU/ml in 50% (57/114) of samples and for the presence of P.aeruginosa in 10% (12/114). NTMs were detected in 16% (18/114) of HCDs: M. chimaera was identified in 11% (13/114) of samples and in 4% (5/114) M. gordonae. All aerosol samples were negative for NTMs, but in the HCDs Maquet, B.cereus were detected in 7% (4/59) of the samples, K.oxytoca in 2% (1/59), B.ursincola in 2% (1/59) and S. paucimobilis in 3% (2/59). Only S. paucimobilis was isolated also in the same HCD water sample. Conclusions The implementation of maintenance and disinfection procedures of HCDs was able to reduce the risk of contamination and aerosolization by NTMs but not of other microorganisms. Key messages Further strategies should be put in place for the cases finding. Moreover, reliable decontamination and identification of agents that can disrupt biofilms and increase chlorine susceptibility of mycobacteria are required.

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