Forecasting ultra-early intensive care strain from COVID-19 in England

Jacob Deasy; Emma Rocheteau; Katharina Kohler; Daniel J. Stubbs; Peitro Barbiero; Pietro Liò; Ari Ercole

The COVID-19 pandemic has rapidly caused an enormous worldwide medical and socioeconomic impact since the first case emerged on November 16th 2019 [1] . Although a self-limiting illness for most, the percentage of COVID-19 patients with hypoxaemic respiratory failure requiring ICU admission for mechanical ventilation translates into large numbers which may challenge healtcare provision. In Northern Italy, an exponential increase in COVID-19 admissions rapidly overwhelmed normal ICU capacity [2] and surge capacity had to be created quickly. The exact reason for the sudden need for ICU surge capacity in Italy, and whether this will generalise to other countries, is unclear, but both demographic factors and healthcare system structure are likely to be important. Notably, UK availability of ICU beds per capita compares poorly with other highincome countries-including Italy [3] . Whilst standard acute wards may be re-purposed easily, creating ICU capacity is constrained by the need for complex equipment and the delivery of highly specialised medical and nursing care. Nevertheless, there are mechanisms by which ICU capacity could be increased in an emergency, including facilitating ICU discharge of recovering patients through liberating downstream beds by reducing elective work, by stopping elective work likely to require ICU admission, or by changing referral policies. Such changes are likely to be relatively quick to implement but have important repercussions for normal healthcare provision and ideally would not be instituted until absolutely necessary. Furthermore, since ICUs in the UK typically undertake a high proportion of emergency work, much of which will continue despite the pandemic, and since occupancy is typically well above 80%, such strategies are likely to result in only a relatively modest increase in capacity. A greater increase in emergency physical capacity for mechanical ventilation could be achieved by opening new level 3 beds with additional equipment (e.g. operating theatre ventilators). This requires significant changes to infrastructure, processes, or sta ng and is therefore logistically complex, expensive, and most importantly slow to implement. Forecasting was therefore essential in guiding such di cult policy decisions in Italy [2] . The explosion of cases seen in Italy means that an early warning of need for surge capacity is likely to be required in other countries including England.