May 17, 2015
The Promise and Perils of Computerised Prescription Systems
Prescribing medications to sick people is a difficult task. The person prescribing needs to choose the right medication, choose the right dose, choose the right timing for delivering those doses, and check whether the medication will interact with any other medications that the patient might already be on.
Clearly, computerised prescription order entry systems (or CPOE) systems have vast potential benefits here. Computers are much better than humans at storing masses of information. In principle, computer systems allow much faster and better access to all kinds of records, which means no more rustling through paper records distributed across several locations.
What’s more, CPOE also allows better stock management. Once medication has been ordered, the system knows exactly how much is needed, how much is still in stock, and can create valuable data sets that can be used to optimise stock management and anticipate demands.
CPOE also generates a data stream that can make it easy to audit prescription patterns and compare those patterns to best practice and evidence-based guidelines.
In short, CPOE is a win-win proposition, and if there is a module that fits with an existing medical record system, there’s no reason why it should not be implemented quickly and efficiently.
That’s what one children’s hospital thought. They were linked to a University Hospital System and treated many children who required urgent access to top specialist medical care. So they rolled out CPOE.
And then, the children died.
In the words of Han and coauthors:
“Univariate analysis revealed that mortality rate significantly increased from 2.80% (39 of 1394) before CPOE implementation to 6.57% (36 of 548) after CPOE implementation. Multivariate analysis revealed that CPOE remained independently associated with increased odds of mortality (odds ratio: 3.28; 95% confidence interval: 1.94–5.55) after adjustment for other mortality covariables.“ (from the abstract)
The authors looked at the data first. They surveyed all children who were transferred to their hospital’s Intensive Care Unit from other hospitals within a time span of 18 months, 12 before and 6 after CPOE introduction. Then, they looked for the reasons.
These children were a special case. They needed the correct treatment, fast. Over the years, the hospital ICU team had evolved procedures that enabled them to be as fast as possible. They were as finely tuned as the team changing the wheels on a Formula 1 racing car.
The new system destroyed these processes, because it was slow. Before, doctors would pass quick written notes to nurses, who were always on the lookout for new instructions. Now, it took up to ten clicks to enter a medication order. Low bandwidth then added another delay until the order was transmitted to the pharmacists. Before, everybody was free to help tend to the patient, if needed. Now, one member of staff had to be at the computer, tending to the CPOE system. Before, staff could just grab what they needed to stabilise the patient. Now, everything went through central ordering.
With hindsight, it is easy to criticise the hospital team for what seems to be a rushed introduction of a system that was not ready for prime time. But if you look at the hype surrounding much of telehealth and telemedicine (“Act now! We know it works! You OWE it to your PATIENTS! (And to the taxpayers …)“), it is easy to see how this might have happened.
You will often hear telemedicine and eHealth evangelists say that the world could be so much better and brighter if it weren’t for those pesky practitioners who are clinging on to the old way of doing things.
In this case, the old way of getting medication to very sick children on arrival in the hospital ICU was actually working very well. Speed, and having as many hands as possible on deck, were essential.
The new way, with its ten clicks to achieve a single order, was more suitable for a situation where prescriptions were not urgent, where safety was paramount, and where there was spare personnel to focus on data entry.
In short, the new way was not usable.
Usability is far more than “do people like it?”. At the very minimum, per ISO 9241 definition, a usable system has to do what it is designed to do (effectiveness), and it has to do so with an appropriate speed (efficiency). If the users like it, that’s nice (user satisfaction), but it’s far from the whole story.
The key point where the CPOE system that Han and colleagues describe fell down was efficiency, which made it unsuitable for the task.
In theory, CPOE is a great idea, but it has to be usable in practice. Otherwise, it just won’t work.
Han, Y. et al. (2005). Unexpected Increased Mortality After Implementation of a Commercially Sold Computerized Physician Order Entry System PEDIATRICS, 116 (6), 1506-1512 DOI: 10.1542/peds.2005-1287