Revised recommendations from the CSO-HNS taskforce on performance of tracheotomy during the COVID-19 pandemic - what a difference a year makes.

BACKGROUND: During the early part of the COVID-19 pandemic, the Canadian Society of Otolaryngology - Head & Neck Surgery (CSO-HNS) task force published recommendations on performance of tracheotomy. Since then, our understanding of the virus has evolved with ongoing intensive research efforts. New literature has helped us better understand various aspects including patient outcomes and health care worker (HCW) risks associated with tracheotomy during the COVID-19 pandemic. Accordingly, the task force has re-evaluated and revised some of the previous recommendations. MAIN BODY: Based on recent evidence, a negative reverse transcription polymerase chain reaction (RT-PCR) COVID-19 swab status is no longer the main deciding factor in the timing of tracheotomy. Instead, tracheotomy may be considered as soon as COVID-19 swab positive patients are greater than 20 days beyond initial symptoms and 2 weeks of mechanical ventilation. Furthermore, both open and percutaneous surgical techniques may be considered with both techniques showing similar safety and outcome profiles. Additional recommendations with discussion of current evidence are presented. CONCLUSION: These revised recommendations apply new evidence in optimizing patient and health care system outcomes as well as minimizing risks of COVID-19 transmission during aerosol-generating tracheotomy procedures. As previously noted, additional evidence may lead to further evolution of these and other similar recommendations.

Recommendations from the CSO-HNS taskforce on performance of tracheotomy during the COVID-19 pandemic.

INTRODUCTION: The performance of tracheotomy is a common procedural request by critical care departments to the surgical services of general surgery, thoracic surgery and otolaryngology - head & neck surgery. A Canadian Society of Otolaryngology - Head & Neck Surgery (CSO-HNS) task force was convened with multi-specialty involvement from otolaryngology-head & neck surgery, general surgery, critical care and anesthesiology to develop a set of recommendations for the performance of tracheotomies during the COVID-19 pandemic. MAIN BODY: The tracheotomy procedure is highly aerosol generating and directly exposes the entire surgical team to the viral aerosol plume and secretions, thereby increasing the risk of transmission to healthcare providers. As such, we believe extended endotracheal intubation should be the standard of care for the entire duration of ventilation in the vast majority of patients. Pre-operative COVID-19 testing is highly recommended for any non-emergent procedure. CONCLUSION: The set of recommendations in this document highlight the importance of avoiding tracheotomy procedures in patients who are COVID-19 positive if at all possible. Recommendations for appropriate PPE and environment are made for COVID-19 positive, negative and unknown patients requiring consideration of tracheotomy. The safety of healthcare professionals who care for ill patients and who keep critical infrastructure operating is paramount.

Perfluorodecalin and bone regeneration.

Perfluorodecalin (PFD) is a chemically and biologically inert biomaterial and, as many perfluorocarbons, is also hydrophobic, radiopaque and has a high solute capacity for gases such as oxygen. In this article we have demonstrated, both in vitro and in vivo, that PFD may significantly enhance bone regeneration. Firstly, the potential benefit of PFD was demonstrated by prolonging the survival of bone marrow cells cultured in anaerobic conditions. These findings translated in vivo, where PFD incorporated into bone-marrow-loaded 3D-printed scaffolds substantially improved their capacity to regenerate bone. Secondly, in addition to biological applications, we have also shown that PFD improves the radiopacity of bone regeneration biomaterials, a key feature required for the visualisation of biomaterials during and after surgical implantation. Finally, we have shown how the extreme hydrophobicity of PFD enables the fabrication of highly cohesive self-setting injectable biomaterials for bone regeneration. In conclusion, perfluorocarbons would appear to be highly beneficial additives to a number of regenerative biomaterials, especially those for bone regeneration.

High levels of HCV core+1 antibodies in HCV patients with hepatocellular carcinoma.

The core region of the hepatitis C virus (HCV) genome possesses an overlapping ORF that has been shown to encode a protein, known as the alternate reading frame protein (ARFP), F or core+1. The biological role of this protein remains elusive, as it appears to be non-essential for virus replication. However, a number of independent studies have shown that the ARFP/F/core+1 protein elicits humoral and cellular immune responses in HCV-infected individuals and interacts with important cellular proteins. To assess the significance of the core+1 humoral response in HCV-infected patients, we examined the prevalence of anti-core+1 antibodies in sera from patients with hepatocellular carcinoma (HCC) in comparison with chronically HCV-infected individuals without HCC. We produced two HCV core+1 histidine-tagged recombinant proteins for genotypes 1a (aa 11-160) and 1b (aa 11-144), as well as a non-tagged highly purified recombinant core+1/S protein (aa 85-144) of HCV-1b. Using an in-house ELISA, we tested the prevalence of core+1 antibodies in 45 patients with HCC in comparison with 47 chronically HCV-infected patients without HCC and 77 negative-control sera. More than 50 % of the serum samples from HCC patients reacted with all core+1 antigens, whereas <26 % of the sera from the non-HCC HCV-infected individuals tested positive. No core+1-specific reactivity was detected in any of the control samples. In conclusion, the high occurrence of anti-core+1 antibodies in the serum of HCC patients suggests a role for the ARFP/F/core+1 protein in the pathogenesis of HCC.