Abstract
A medication safety issue that we believe warrants urgent and thorough investigation is mental health nurses’ administration of i.m. injections. In brief, the problem is that many patients are not currently receiving their medication as it is prescribed. Historically, nurses have been taught to use the dorsogluteal site for the majority of i.m. injections. The rationale for the use of this site was that the gluteus maximus is a large muscle, which is particularly suited to high-volume injections and for depot or slow-release preparations such as some antipsychotics.
Up to 92% of i.m. injections made into the dorsogluteal site are delivered into subcutaneous tissue [1]. I.m. preparations injected into subcutaneous tissue may be poorly absorbed and can cause complications, such as injection granuloma. For overweight or obese patients, standard injection needles are of insufficient length to deliver i.m. medication [2]. Although administering injections using longer needles is possible, anecdotal evidence suggests that nurses are reluctant to use longer needles because they do not wish to cause patients undue pain. Because people with psychiatric conditions have higher rates of obesity than the general population [3], there is a greater risk that medications intended for i.m. administration will be administered s.c.
Nursing students in many Australian universities are taught that the ventrogluteal site is the preferred site for i.m. injections and that the dorsogluteal site should not be used at all. The practice reality is that most mental health nurses use the dorsogluteal site as a matter of course. Consequently, students have no opportunity for supervised practice using the ventrogluteal site when on clinical placement. These problems are compounded by the publication of conflicting information in the academic literature.
The use of the dorsogluteal site is also problematic because of the risk of damage to the sciatic nerve and of delivering medication into major blood vessels. The literature is replete with cases of i.m. injections causing sciatic nerve damage, and there have been several court judgements in favour of patients who have experienced injuries from injections into the dorsogluteal site [4]. Our investigations suggest that the ventrogluteal, deltoid, and vastus lateralis sites are viable, and probably safer, alternatives. More work needs to be conducted, however, to establish the injection sites that are most appropriate, taking into account the diverse range of environments in which mental health nurses administer medication (e.g. inpatient units, community settings) and the preferences of patients.
In summary, the majority of i.m. injections in Australian mental health services are administered in a way that is likely to fail to deliver the medication as intended in a large proportion of cases. The development of clinical practice guidelines for i.m. injection and strategies to ensure their implementation are urgently needed.