Skin-to-deltoid-muscle distance at three recommended sites for intramuscular vaccination in a population with obesity: an observational study

The study also explored i) the associations between skin-to-deltoid-muscle distance across the three recommended sites with sex, body mass index (BMI), and arm circumference, and ii) the proportion of participants with a skin-to-deltoid-muscle distance >20 millimetres (mm), in whom the standard 25mm needle length would not ensure deposition of vaccine within the deltoid muscle. method: When choosing the required needle length to achieve intramuscular vaccination in obese vaccine recipients, consideration needs to be given to the injection site location, sex, BMI and/or arm circumference, as these factors all influence the skin-to-deltoid-muscle distance. Published data report that a standard needle length (25mm) is suitable for most people with a body mass index (BMI) <25 kilograms [kg]/m2.48 However, progressively higher BMIs increase the likelihood of requiring a longer-than-standard needle length for deltoid intramuscular injection.810 Worldwide, immunisation guidelines vary in their instructions on how to choose the correct needle length based on BMI and body weight, or contain non-specific terms such as "larger arms".1113 An accurate measurement of BMI for a vaccine recipient is not always readily available and the interpretation of arm size is subjective, resulting in an increased risk of inappropriate needle length choice and subcutaneous vaccine delivery. An observational study of a SARS-CoV-2 mRNA vaccine, administered with needles of different lengths at the discretion of the vaccinator, did not demonstrate a difference in immunogenicity between those vaccinated with a needle of sufficient versus insufficient length to achieve intramuscular deposition of vaccine.14 However, there is evidence that intramuscular injection results in significantly better immune response compared to subcutaneous delivery of influenza and hepatitis B vaccines.15 Further, there is high-grade evidence that subcutaneous administration of different vaccine types (adjuvanted, live virus and non-adjuvanted) is associated with increased local side effects including abscess and granuloma formation, compared to intramuscular delivery.15" The location of the deltoid intramuscular injection site is defined variably between countries based on anatomical landmarks (Figure 1).

COVID-19 vaccination and the skin to deltoid MUSCLE distance in adults with diabetes.

Objectives: To estimate the proportion of adult diabetics with a skin to deltoid muscle distance (SDMD) of > 25 mm, representing a distance greater than the standard needle length used for intramuscular COVID-19 vaccination, and to assess whether anthropometric measurements predict ultrasound SDMD measurements. Design: Non-interventional cross-sectional study. Setting: Single site, non-clinical setting, Wellington, New Zealand. Participants: One hundred participants (50 females) aged at least 18 years diagnosis with diabetes. All participants completed the study. Main outcome measures: The proportions of participants with a SDMD > 25 mm and a SDMD > 20 mm (indicating that the needle would not have penetrated at least 5 mm into the deltoid, which is considered necessary to ensure deposition of vaccine into muscle); the relationship between anthropometric measurements (body weight, body height, body mass index (BMI), skinfold thickness, arm circumference) and SDMD measured by ultrasound. Results: The proportion (95 %CI) of participants with a SDMD > 25 mm was 6/100; 6 % (2.2 to 12.6), and the proportion with a SDMD > 20 mm was 11 % (5.6 to 18.8), of which 9/11 had a BMI ≥ 30 kg/m2 and 9/11 were female. The strongest relationships between anthropometric measurements and SDMD were with arm circumference (r = 0.76, P < 0.001) and BMI (r = 0.73, P < 0.001). Arm circumference and BMI were the best predictors of SDMD measurements with AUC for ROC curves of 0.99 and 0.94 above the 25 mm cut point, 0.97 and 0.89 above the 20 mm cut point respectively. Conclusions: The standard needle length of 25 mm is likely to be insufficient to ensure deposition of COVID-19 vaccine within the deltoid muscle in a small but important proportion of obese adults with diabetes. Arm circumference and BMI are simple measurements that could identify those that need a long needle to ensure successful intramuscular vaccine administration. Funding: Ruth Maud Ring Spencer Estate; Health Research Council of New Zealand (Independent Research Organisation).

Automatic versus manual oxygen titration using a novel nasal high-flow device in medical inpatients with an acute illness: a randomised controlled trial.

BACKGROUND: Guideline recommendations state oxygen should be administered to acutely unwell patients to achieve a target oxygen saturation (SpO2) range. The current practice of manual oxygen titration frequently results in SpO2 outside of a prescribed range. The aim of this study was to assess the efficacy of automatic oxygen titration using a closed-loop feedback system to achieve SpO2 within a prescribed target range METHODS: An open-label randomised parallel group trial was undertaken comparing automatic oxygen titration using a novel nasal high-flow device to manual oxygen titration using nasal high flow. Medical inpatients requiring oxygen therapy in Wellington Regional Hospital, New Zealand with a prescribed target SpO2 range of 88%-92% or 92%-96% were recruited and randomised equally between the interventions for a period of 24 hours. The primary outcome was the proportion of time spent with SpO2 within the prescribed range. RESULTS: 20 patients were included in the analysis. Automatic oxygen titration resulted in a median (IQR) 96.2% (95.2-97.8) of time within the target range compared with 71% (59.4-88.3) with manual titration; difference (95% CI) 24.2% (7.9% to 35%), p<0.001. There was a reduction in the time spent with SpO2 ≥2% above and ≥2% below range in the automatic titration group, although the point estimate for the differences were small; -1% (-8.2% to -0.04%), p=0.017 and -2.4% (-11.5% to 0.3%), p=0.05 respectively. CONCLUSIONS: Nasal high-flow with automatic oxygen titration resulted in a greater proportion of time spent with SpO2 in target range compared with manual titration. TRIAL REGISTRATION: The trial was registered with the Australian and New Zealand Clinical Trials Registry (ACTRN12619000901101).

How big is your bubble? Characteristics of self-isolating household units ('bubbles') during the COVID-19 Alert Level 4 period in New Zealand: a cross-sectional survey.

OBJECTIVE: To characterise the self-isolating household units (bubbles) during the COVID-19 Alert Level 4 lockdown in New Zealand. DESIGN, SETTING AND PARTICIPANTS: In this cross-sectional study, an online survey was distributed to a convenience sample via Facebook advertising and the Medical Research Institute of New Zealand's social media platforms and mailing list. Respondents were able to share a link to the survey via their own social media platforms and by email. Results were collected over 6 days during Alert Level 4 from respondents living in New Zealand, aged 16 years and over. MAIN OUTCOMES MEASURES: The primary outcome was the mean size of a self-isolating household unit or bubble. Secondary outcomes included the mean number of households in each bubble, the proportion of bubbles containing essential workers and/or vulnerable people, and the mean number of times the home was left each week. RESULTS: 14 876 surveys were included in the analysis. The mean (SD) bubble size was 3.58 (4.63) people, with mean (SD) number of households 1.26 (0.77). The proportion of bubbles containing one or more essential workers, or one or more vulnerable persons was 45.3% and 42.1%, respectively. The mean number of times individual bubble members left their home in the previous week was 12.9 (12.4). Bubbles that contained at least one vulnerable individual had fewer outings over the previous week compared with bubbles that did not contain a vulnerable person. The bubble sizes were similar by respondent ethnicity. CONCLUSION: In this New Zealand convenience sample, bubble sizes were small, mostly limited to one household, and a high proportion contained essential workers and/or vulnerable people. Understanding these characteristics from a country which achieved a low COVID-19 infection rate may help inform public health interventions during this and future pandemics.

Using comics and curiosity to drive pandemic research on a national scale.

An independent online Public Health survey regarding the COVID-19 pandemic was conducted during an Alert Level 4 lockdown, the highest possible, in New Zealand. An illustrated and curiosity-driven public engagement campaign was designed to advertise survey participation, and performance compared with a standard approach using randomised controlled A/B Split tests. The 'Caretoon' approach featured comic illustrations, appealed to goodwill and was intended to pique curiosity. This linked to an illustrated version of the survey which, upon completion, gave a personalised comic summary showing how respondent's answers compared with national averages. The standard ad and survey were not illustrated with comics, and did not provide a personalised comic summary on completion. Both approaches were cost- and time-effective, together resulting in 18,788 responses over six days. The Caretoon approach outperformed the standard approach in terms of the number of people reached, engaged, survey link clicks, gender and ethnic diversity amongst respondents, and cost-effectiveness of advertising. This came at the expense of a small reduction in the proportion of completed surveys and male respondents. The research evidences objective value of public engagement activity, comics and curiosity as tools which can support Public Health research on a national scale.