The clinical impact of maternal COVID-19 on mothers, their infants, and placentas with an analysis of vertical transfer of maternal SARS-CoV-2-specific IgG antibodies.

INTRODUCTION: The effect of SARS-CoV-2 severity or the trimester of infection in pregnant mothers, placentas, and infants is not fully understood. METHODS: A retrospective, observational cohort study in Chapel Hill, NC of 115 mothers with SARS-CoV-2 and singleton pregnancies from December 1, 2019 to May 31, 2021 via chart review to document the infants' weight, length, head circumference, survival, congenital abnormalities, hearing loss, maternal complications, and placental pathology classified by the Amsterdam criteria. RESULTS: Of the 115 mothers, 85.2% were asymptomatic (n = 37) or had mild (n = 61) symptoms, 13.0% had moderate (n = 9) or severe (n = 6) COVID-19, and 1.74% (n = 2) did not have symptoms recorded. Moderate and severe maternal infections were associated with increased C-section, premature delivery, infant NICU admission, and were more likely to occur in Type 1 (p = 0.0055) and Type 2 (p = 0.0285) diabetic mothers. Only one infant (0.870%) became infected with SARS-CoV-2, which was not via the placenta. Most placentas (n = 63, 54.8%) did not show specific histologic findings; however, a subset showed mild maternal vascular malperfusion (n = 26, 22.6%) and/or mild microscopic ascending intrauterine infection (n = 28, 24.3%). The infants had no identifiable congenital abnormalities, and all infants and mothers survived. DISCUSSION: Most mothers and their infants had a routine clinical course; however, moderate and severe COVID-19 maternal infections were associated with pregnancy complications and premature delivery. Mothers with pre-existing, non-gestational diabetes were at greatest risk of developing moderate or severe COVID-19. The placental injury patterns of maternal vascular malperfusion and/or microscopic ascending intrauterine infection were not associated with maternal COVID-19 severity.

Aerosolisation during tracheal intubation and extubation in an operating theatre setting.

Aerosol-generating procedures such as tracheal intubation and extubation pose a potential risk to healthcare workers because of the possibility of airborne transmission of infection. Detailed characterisation of aerosol quantities, particle size and generating activities has been undertaken in a number of simulations but not in actual clinical practice. The aim of this study was to determine whether the processes of facemask ventilation, tracheal intubation and extubation generate aerosols in clinical practice, and to characterise any aerosols produced. In this observational study, patients scheduled to undergo elective endonasal pituitary surgery without symptoms of COVID-19 were recruited. Airway management including tracheal intubation and extubation was performed in a standard positive pressure operating room with aerosols detected using laser-based particle image velocimetry to detect larger particles, and spectrometry with continuous air sampling to detect smaller particles. A total of 482,960 data points were assessed for complete procedures in three patients. Facemask ventilation, tracheal tube insertion and cuff inflation generated small particles 30-300 times above background noise that remained suspended in airflows and spread from the patient's facial region throughout the confines of the operating theatre. Safe clinical practice of these procedures should reflect these particle profiles. This adds to data that inform decisions regarding the appropriate precautions to take in a real-world setting.