Cricoid pressure has been long used by clinicians to reduce the risk of aspiration during tracheal intubation. Historically, it is defined by Sellick as temporary occlusion of the upper end of the oesophagus by backward pressure of the cricoid cartilage against the bodies of the cervical vertebrae. The clinical relevance of cricoid pressure has been questioned despite its regular use in clinical practice. In this review, we address some of the controversies related to the use of cricoid pressure.
Cricoid Cartilage ; physiology ; Evidence-Based Medicine ; Humans ; Intubation, Intratracheal ; methods ; Pneumonia, Aspiration ; prevention & control ; Pressure

INTRODUCTION: Vaccination remains a key strategy to living endemically with COVID-19. The Pfizer-BioNTech COVID-19 vaccine was first granted interim authorisation for use in Singapore in December 2020. With overseas studies published about the safety and side effect profiles of mRNA COVID-19 vaccines focusing mainly on non-Asian populations, we described the side effects of Pfizer-BioNTech COVID-19 vaccination experienced by the healthcare workers (HCWs) in a tertiary hospital in Singapore. METHODS: Data were obtained from the Occupational Health Clinic (OHC) at the National University Hospital in Singapore, which monitored staff for any adverse effects within 30 minutes post vaccination on-site and any adverse effects after that. A cross-sectional study among the vaccinated HCWs was conducted using an online survey, which established basic demographics, histories of allergies or atopic disorders, and adverse events encountered after dose 1 and dose 2 of vaccination. RESULTS: No anaphylaxis was reported. Most common symptom was giddiness (32.7%) experienced by HCWs within 30 minutes. Adverse events attended post-vaccination by OHC were generally mild and self-limiting. From the survey, odds of experiencing an adverse event after dose 2 was significantly higher than after the first dose, especially for fever/chills (odds ratio [OR] 22.5). Fever/chills, injection site reactions, headache, aches and pains, and feeling unwell were significantly more common in HCWs below 60 years compared to those ≥60 years. An allergy to food (adjusted OR 2.7) and a history of eczema/sensitive skin (adjusted OR 2.6) were associated with a skin reaction not at injection site. CONCLUSION The side effects experienced after Pfizer-BioNTech COVID-19 vaccines are generally self-limiting and mild, with no anaphylaxis reported.
COVID-19 ; COVID-19 Vaccines ; Cross-Sectional Studies ; Health Personnel ; Humans ; SARS-CoV-2 ; Singapore/epidemiology* ; Tertiary Care Centers ; Vaccination