Estimating pandemic critical care drug requirements

Pharmacist Anita Hogg explains how the Medicines Optimisation Innovation Centre (MOIC) in Belfast developed and applied a model to estimate the critical care drug requirements during the covid-19 pandemic.

“One of things we wanted to do was to make sure that we had a process to estimate critical care drug requirements – what drugs and how much would be required for individual patients and for the wider health care system as a whole”, says Ms Hogg.

From the outset, the MOIC adopted a collaborative approach across all the relevant sectors. The first step was to identify the likely critical care drug requirements per patient and then to check them against emerging real world data. “Remember this was an evolving situation with more information becoming available on a weekly basis”, says Ms Hogg.  Real world data were drawn from Northern Ireland and also from ICNARC, the UK-wide Intensive Care National Audit and Research Centre. An unpublished tool that had been developed by Mark Borthwick and colleagues in England when dealing with the 2009 H1N1 swine flu pandemic provided some key elements of the model. This enabled the MOIC team to build a model that incorporated assumptions about the proportions of intensive care patients likely to need specific drugs in a particular therapeutic class together with an estimated duration of therapy for a typical ICU length of stay.

A good example is the neuromuscular blockers – something that made worldwide headline news because without neuromuscular blockers it is impossible to ventilate patients “It’s like having a car without petrol – and there were a lot of very worried clinicians on the ground”, says Ms Hogg.

The model assumed that about 85% of patients in ICU would need a neuromuscular blocker for a period of 7-8 days in a typical ICU stay of about 12 days. About 70% of patients who required a neuromuscular blocker would receive cisatracurium, about 20% rocuronium and the remaining 10% atracurium. Using this information, with support of colleagues they were able to map requirements for the current situation and for potential surges. The numbers were matched against the stock held in hospital and at pharmaceutical wholesalers in Northern Ireland and the current capacity was estimated.

The availability of drugs was RAG (red, amber, green)-rated. Thus, more than 14-days’ supply that was rated green, 7-14 days was amber and less than seven days was rated red. This gave a picture, as accurately as possible, of overall capacity in Northern Ireland.

A full report of this work can be found here.

Hogg A, Huey R, Scott MG, et al. Informing critical care drug requirements in response to the COVID-19 pandemic. Eur J Hosp Pharm. 2020;27:263–266.