Blood haemoglobin and pulse oximetry oxygen saturation measurement error

Pulse oximetry utilises the differential absorption, by both oxy- and deoxyhaemoglobin, of a light signal passing through tissue to provide a measure of blood oxygen saturation. Although pulse oximetry devices are widely used to monitor patients in real time, and to provide an estimate of risk of deterioration, no studies exist on the association of haemoglobin levels and pulse oximetry measurement error. We examined the effect of different haemoglobin levels on pulse oximetry measurements in patients admitted to a large UK teaching hospital from 1 February 2020 to 31 December 2021 with a possible diagnosis of Covid-19 infection. Pulse oximetry and arterial blood gas oxygen saturations were compared. Two measures of blood haemoglobin levels were available;from a venous sample within 24 hours of the arterial blood gas sampling and directly from the arterial blood gas sample itself. Data were available from 1086 patients. Using the measurement of haemoglobin from the venous blood sample within 24 hours of the blood gas, there was an inverse linear association between haemoglobin and pulse oximetry measurement error of -0.06% per 1 g/L increase of haemoglobin (95% confidence intervals CI: -0.02 to -0.09). This equates to patients with a venous haemoglobin of 70g/L having a measurement error of +8.0% (95% CI: +5.9% to +10.0%) and those with a haemoglobin of 150g/L having a measurement error of +3.6% (95% CI: +2.2% to +4.9%). Similar associations were observed using arterial haemoglobin values. The association between haemoglobin and measurement error of oxygen saturation as determined by pulse oximetry is inverse and linear. It is relatively large in patients with anaemia and may affect clincial assessment.

The changing vaccine landscape: rates of COVID-19 vaccine acceptance and hesitancy in young adults during vaccine rollout.

AIMS: Development and rollout of vaccines offers the best opportunity for population protection against the SARS-CoV-2 (COVID-19) virus. However, hesitancy towards the vaccines might impede successful uptake in the United Kingdom, particularly in young adults who demonstrate the highest rates of hesitancy. This prospective study explored COVID-19 vaccine hesitancy in young adults and whether the reasons behind these attitudes changed during the initial stages of the United Kingdom's vaccine rollout. METHOD: Data on vaccination intention were collected from a British university student cohort at three time points: October 2020, February 2021, and March 2021. This online survey included items on intention to receive a vaccine and a free-text response for the reasons behind this intention. Cochran's Q tests examined changes in rates of hesitancy and acceptance over time and free-text responses were analysed thematically. RESULTS: At baseline, 893 students provided data, with 476 participants completing all three time points. Hesitancy declined over time, with 29.4% of participants expressing hesitancy at baseline, reducing to 9.1% at wave 2 and 5.9% at wave 3. The most commonly endorsed themes for those willing to accept a vaccine were self-protection against COVID-19 and pro-social reasons, including protecting the population or unspecific others, and ending the pandemic/returning to normal life. The most commonly endorsed hesitancy themes related to 'confidence' in the vaccines and potential personal risk, including insufficient testing/scientific evidence, concern about side effects, and long-term effects. These reasons remained the most commonly endorsed at both waves 2 and 3. CONCLUSIONS: While a decline in hesitancy was observed over time, the key reasons behind both vaccine acceptance and hesitancy remained consistent. Reasons behind hesitancy aligned with those of the general public, providing support for the use of generalist interventions. Pro-social reasons frequently underpinned vaccine acceptance, so cohort-specific interventions targeting those factors may be of benefit.

Understanding and addressing vaccine hesitancy in the context of COVID-19: development of a digital intervention.

OBJECTIVES: Severe Acute Respiratory Coronavirus 2 (SARS-CoV-2) was identified in late 2019, spreading to over 200 countries and resulting in almost two million deaths worldwide. The emergence of safe and effective vaccines provides a route out of the pandemic, with vaccination uptake of 75-90% needed to achieve population protection. Vaccine hesitancy is problematic for vaccine rollout; global reports suggest only 73% of the population may agree to being vaccinated. As a result, there is an urgent need to develop equitable and accessible interventions to address vaccine hesitancy at the population level. STUDY DESIGN: & Method: We report the development of a scalable digital intervention seeking to address COVID-19 vaccine hesitancy and enhance uptake of COVID-19 vaccines in the United Kingdom. Guided by motivational interviewing (MI) principles, the intervention includes a series of therapeutic dialogues addressing 10 key concerns of vaccine-hesitant individuals. Development of the intervention occurred linearly across four stages. During stage 1, we identified common reasons for COVID-19 vaccine hesitancy through analysis of existing survey data, a rapid systematic literature review, and public engagement workshops. Stage 2 comprised qualitative interviews with medical, immunological, and public health experts. Rapid content and thematic analysis of the data provided evidence-based responses to common vaccine concerns. Stage 3 involved the development of therapeutic dialogues through workshops with psychological and digital behaviour change experts. Dialogues were developed to address concerns using MI principles, including embracing resistance and supporting self-efficacy. Finally, stage 4 involved digitisation of the dialogues and pilot testing with members of the public. DISCUSSION: The digital intervention provides an evidence-based approach to addressing vaccine hesitancy through MI principles. The dialogues are user-selected, allowing exploration of relevant issues associated with hesitancy in a non-judgmental context. The text-based content and digital format allow for rapid modification to changing information and scalability for wider dissemination.

The impact of COVID-19 on national screening programmes in England.

OBJECTIVES: This study aimed to review the trends in adult national screening programme performance in England before and during the COVID-19 pandemic and consider the future implications. STUDY DESIGN: This was a quantitative, longitudinal study. METHODS: Publicly available data on quarterly uptake of the five adult screening programmes in England were obtained from Public Health England. Trends from 2017 to 2021 were reviewed and discussed. RESULTS: From 2019 to 2020 Q4, there were substantial reductions in performance in four of the five national screening programmes that were not in keeping with recent trends. CONCLUSION: The reductions in screening performance coincide with the arrival of the COVID-19 pandemic in England and may be explained by the temporary suspension of national screening programmes, and the inability or unwillingness of invitees to partake in screening once the programmes had been restored. Because of the delay in publication of the analysed data, further COVID-19 lockdowns in recent months make it probable that the current true screening performance figures are substantially lower than those presented in this article. The impact on screening programme performance is likely to be detrimental to patient outcomes, meaning remedial action is urgently required.

Students' Views towards Sars-Cov-2 Mass Asymptomatic Testing, Social Distancing and Self-Isolation in a University Setting during the COVID-19 Pandemic: A Qualitative Study

We aimed to explore university students' perceptions and experiences of SARS-CoV-2 mass asymptomatic testing, social distancing and self-isolation, during the COVID-19 pandemic. This qualitative study comprised of four rapid online focus groups conducted at a higher education institution in England, during high alert (tier 2) national COVID-19 restrictions. Participants were purposively sampled university students (n = 25) representing a range of gender, age, living circumstances (on/off campus), and SARS-CoV-2 testing/self-isolation experiences. Data were analysed using an inductive thematic approach. Six themes with 16 sub-themes emerged from the analysis of the qualitative data: 'Term-time Experiences', 'Risk Perception and Worry', 'Engagement in Protective Behaviours', 'Openness to Testing', 'Barriers to Testing' and 'General Wellbeing'. Students described feeling safe on campus, believed most of their peers are adherent to protective behaviours and were positive towards asymptomatic testing in university settings. University communications about COVID-19 testing and social behaviours need to be timely and presented in a more inclusive way to reach groups of students who currently feel marginalised. Barriers to engagement with SARS-CoV-2 testing, social distancing and self-isolation were primarily associated with fear of the mental health impacts of self-isolation, including worry about how they will cope, high anxiety, low mood, guilt relating to impact on others and loneliness. Loneliness in students could be mitigated through increased intra-university communications and a focus on establishment of low COVID-risk social activities to help students build and enhance their social support networks. These findings are particularly pertinent in the context of mass asymptomatic testing programmes being implemented in educational settings and high numbers of students being required to self-isolate. Universities need to determine the support needs of students during self-isolation and prepare for the long-term impacts of the pandemic on student mental health and welfare support services.