Evidence associating neutrophilia, lung damage, hyperlactatemia, blood acidosis, impaired oxygen transport, and mortality in critically ill COVID-19 patients (preprint)

Background: COVID-19 severity and high in-hospital mortality are often associated with severe hypoxemia, hyperlactatemia, and acidosis. Since neutrophil numbers in severe COVID-19 can exceed 80% of the total circulating leukocytes and that they are massively recruited to infected lungs, we investigated whether metabolic acidosis mediated by the glycolytic neutrophils is associated with lung damage and impaired oxygen delivery in critically ill patients. Methods: Based on prospective mortality outcome, 102 critically ill-hospitalized COVID-19 patients were divided into two groups: ICU-Survivors (ICU-S, n=36) and ICU-Non-survivors (ICU-NS, n=66). Blood samples were collected from patients and control subjects to explore correlations between neutrophil counts, lung damage, glycolysis, blood lactate, blood pH, hemoglobin oxygen saturation, and mortality outcome. We also interrogated isolated neutrophils for glycolytic activities and for apoptosis using high-throughput fluorescence imaging complemented with transcriptomic analyses. Stratified survival analyses were conducted to estimate mortality risk associated with higher lactate among predefined subgroups. Results: Neutrophil counts were consistently higher in critically ill patients while exhibiting remarkably lower apoptosis. Transcriptomic analysis revealed miRNAs associated with downregulation of genes involved in neutrophils apoptosis. Both CT lung damage scores and neutrophil counts predicted mortality. Severinghaus fitting of hemoglobin oxygen saturation curve revealed a right-shift indicating lower oxygen capacity in non-survivors, which is consistent with lower blood-pH observed in the same group. Levels of blood lactate were increased in patients but significantly more in the ICU-NS relative to the control group. ROC analysis followed by Kaplan-Meyer survival analysis stratified to the obtained cut-off values showed that CT damage scores, neutrophil counts, and lactate levels are predictors of mortality within 15 days following blood collection. Conclusion: The current results implicate neutrophilia as a potential player in metabolic acidosis and deranged oxygen delivery associating SARS-CoV-2 infection thus contributing to mortality outcome.

Exploring Breastfeeding Mothers’ and Lactation Consultants’ Experiences of Lactation Consultancy Throughout the Restrictions Put in Place Due to the COVID-19 Pandemic. (preprint)

Background Breastfeeding rates in Ireland are among the lowest in the world. Lactation consultancy provides mothers with support and information on how to cope with any challenges they encounter. There is emerging evidence that COVID-19 restrictions impacted access to and the quality of breastfeeding support.Aim The aim of this study was to explore breastfeeding mothers’ and lactation consultants’ experiences of breastfeeding support throughout the COVID-19 restrictions in Ireland. It also aimed to explore what adaptations had to be made to the delivery of lactation consultancy and how these changes impacted mothers’ experiences of breastfeeding support.Methods A qualitative research design was chosen. Semi-structured interviews were conducted with eight participants, three breastfeeding mothers and five lactation consultants. Interviews were conducted online via Zoom, audio-recorded and transcribed. The data were analysed using thematic analysis.Results Five key themes were identified: ‘Lack of Support’, ‘Adapting to COVID-19 Restrictions’, Emotional Response to COVID-19 and Restrictions’, Vaccination as a Barrier to and Facilitator of Support’ and Inconsistency of Lactation Support Across Ireland’. Both lactation consultants and mothers identified similar issues however, slight variations within lactation consultants' perceptions of mothers’ and mothers’ attitudes towards online services were seen. An unanticipated finding was the lack of support in hospitals pre-COVID-19.Conclusions Both mothers’ and lactation consultants’ experiences of lactation consultancy were impacted by the COVID-19 restrictions. Although exacerbated by COVID-19, the lack of support in hospitals existed before COVID-19. Provision of better breastfeeding support is required.Recommendations Increased availability of lactation consultants and the implementation of breastfeeding rooms within hospitals is required in addition to debrief counselling sessions for lactation consultants. Further research is required to understand the unavailability of lactation consultants in hospital settings and to identify how to manage breastfeeding support in future emergency situations.