Design and testing of the safety of the SARUS-CPR hood for novice resuscitators.

BACKGROUND AND AIMS: Bystanders should be protected against aerosols, droplets, saliva, blood and vomitus during resuscitation after cardiac arrest The SARUS (safer - airway - resuscitation) CPR airway hood™ is a clear plastic cover and integrated mask that envelopes the head and torso. Our objectives were to test leakage using saline aerosol generation tests, then assess the performance of the hood during mock cardio-pulmonary resuscitation on a manikin. METHODS: A checklist was validated by comparing the performance of 10 novices against 10 experts during mock resuscitation. Thereafter, 15 novices were tested with and without the hood, in a randomised cross-over study, one week apart. RESULTS: Laboratory analysis showed a > 99% reduction of saline particles detected 5 cm, 75 cm and 165 cm above volunteers wearing the hood. On manikins, experts scored better compared to novices, 8.5 (0.7) vs 7.6 (1.2), difference (95%CI) 0.9 (0.4-1.3), P = 0.0004. Novice performance was equivalent using the hood and standard equipment, 7.3 (1.4) vs 7.3 (1.1) respectively, difference (90%CI) 0.0 (-0.3 - 0.3), P = 0.90. CONCLUSION: Aerosol transmission reduced in the breathing zone. Simulated resuscitation by novices was equivalent with and without the hood.

Environmental impact of volatile anaesthetic use in Scotland over a 3-year period

Volatile anaesthetic agents are potent greenhouse gases (GHGs), representing approximately 5% of the carbon footprint of acute NHS services [1]. Desflurane is an especially potent GHG, with a global warming potential of 1620 CO2 equivalents (CO2e), compared with 210 CO2e for sevoflurane [2]. Efforts to promote environmentally responsible anaesthesia continue, mostly through education and spreading the message through the Scottish Environmental Anaesthesia Group. We aimed to measure changing patterns of volatile anaesthetic use over 3 years, and snapshot nitrous oxide use, within NHS Scotland. Methods The project was registered with clinical governance in NHS Tayside. We quantified volatile use in Scotland from 2018 to 2021 using purchasing data for each territorial health board on a quarterly basis, from point of peak use to the third quarter (Q3) of the 2020/2021 financial year. This was calculated per head of catchment population, with CO2e calculated using the data published by Sulbaek Andersen et al. [1]. Additionally, a survey of anaesthetists within Scotland was carried out to determine patterns of fresh gas flow rates and nitrous oxide use nationally. Results Desflurane fell from a mean of 17.2% to 9.6% of volatile use across larger Scottish hospitals from 2018 to 2021. Between health boards, desflurane use varied from 64.7 to 0 ml per 1000 catchment population, per quarter, at the end of the study period (Fig. 1). A sustained downward trend in desflurane was noted in most health boards, and overall consumption steeply declined, even outwith the COVID-19 pandemic. One hundred and sixty-six anaesthetists responded to the survey. The most common flow rate during maintenance was 0.5-1.9 min-1. Of the anaesthetists, 86% 'rarely' or 'never' used nitrous oxide, with only two anaesthetists out of 166 using it 'always' or 'often'. Default fresh gas flow on anaesthetic machines varied between hospitals and sometimes within hospitals. Figure 1 Desflurane use per quarter per health board. Discussion Even once the effects of COVID-19 are considered, we demonstrate a sustained reduction in desflurane use over 3 years, across an NHS catchment population of 5.5 million. This represents substantial reductions in CO2e emissions. Further reductions in desflurane and nitrous oxide purchasing could offer large environmental and financial benefits. At least one major hospital in Scotland is now decommissioning its nitrous oxide manifold and switching to cylinders for occasional use. Reducing default fresh gas flow rates on anaesthetic machines may offer a means of further reducing unnecessary volatile expenditure.