19 Jan 2011 | Medication Safety
Following a medication error which involved potassium chloride, Capital & Coast DHB introduced a number of changes to control the storage, supply and administration of intravenous potassium.
Potassium chloride is used to prevent or treat low blood levels of potassium, and is critical for optimal cardiac function. Potassium di-hygdrogen phosphate is used to treat low blood levels of phosphate which is essential in cell function. However, intravenous forms of these medications can cause cardiac arrest if administered by rapid direct intravenous injection.
The DHB reviewed the event to understand what had happened and to improve and strengthen safety systems with the aim of preventing any similar events in the future.
Patient Safety Officer Kate MacIntyre says the review identified that the main reason for the error was that two medications, which look very similar, were stored next to each other in the main drug cupboard, and the wrong one was selected.
Subsequently Capital & Coast DHB introduced an organisation-wide policy on the storage, supply and administration of intravenous potassium. The policy includes guidance on prescribing potassium and specifies clear labelling, storage and checking requirements.
Kate MacIntyre says the concentrated version of the medication, which comes in sealed plastic ampoules, must now be stored in labelled containers in either controlled drug safes or computerised medication stations.
‘Wherever possible, intravenous bags premixed with the right amount of potassium are the first choice of treatment and we only use the concentrated ampoules where there is no other option,’ she says.
’This has meant we now only stock the ampoules in a few specialist clinical areas whereas before they were available in most clinical areas. Just by using more premixed IV fluids, having fewer ampoules stored in wards and having them more securely stored, we have reduced the risk.’
She says, as with all change, the DHB has had to evaluate how well it is working and in one area had to reintroduce the ampoules because the right premix is not available in New Zealand at the moment.
‘However, these ampoules are now stored in the ward controlled drug safe and not in the ward medication cupboard.’
In intensive care, where large volumes of potassium chloride are stored, it is not practical to store the ampoules in the locked safe. However, they are separated from other medications in labelled containers in the wider controlled drug cupboard.
Kate MacIntyre says the policy has been widely publicised to staff by teaching sessions, a newsletter and emails to all staff, posters in all areas and walk-around audits.
‘We also sent a learning report to every DHB so they could understand what happened and apply what we learned and changed here to their DHB if it was relevant.’
Since the introduction of the new policy, no serious adverse events involving potassium have occurred.