| dc.description.abstract | Background: Antibiotics are drugs that are used to treat infections caused by bacteria. Approximately one third of hospital inpatients are prescribed an antibiotic at some point during their hospital stay. Prescribing errors contribute to many patient safety incident reports with some degree of prescribing error affecting up to 50% of hospital admissions. Gentamicin is one of the most frequently prescribed aminoglycoside antibiotics in UK hospitals. However, despite its common use in clinical practice, it is challenging to prescribe due to its low oral bioavailability and a narrow therapeutic index. The evidence basis for prescribing is limited and consequently each Hospital Trust in the UK has developed their own individual prescribing protocol. Aim: To explore two distinct protocols for prescribing gentamicin in hospital settings, in order to understand the mechanisms they trigger and the outcomes they achieve. Objective 1: To elicit an initial Programme Theory (IPT) by analysis of the protocols that articulate the intended process of gentamicin prescribing in the two hospital settings (Phase 1) Objective 2: To test the IPT using empirical data from a mixed methods study in order to identify the important contexts, mechanisms and outcomes associated with the actual process of gentamicin prescribing (Phase 2) Objective 3: To refine the Programme Theory in order to understand what works (outcome) as well as how (mechanisms) and under what conditions (context) in terms of gentamicin prescribing in the hospital setting (Phase 3) Methods: This study was a realist evaluation and was conducted in three phases: IPT generation, testing and refinement (as stated above). We used a mixed methods approach to collect the empirical data. The quantitative data collection was in the form of a clinical audit reviewing the ‘accuracy’ of gentamicin prescribing at each site. A secondary purpose of the audit was to assess clinical outcomes and provide quantitative data to triangulate with our qualitative data sources in order to support our theories. The clinical audit commenced at the same time as the initial programme theory was developed and continued alongside the qualitative research. The qualitative research involved semi-structured audio-recorded interviews of healthcare professionals’ experiences of prescribing gentamicin. The qualitative and quantitative data were analysed together and integrated. The RAMESES II reporting standards and COREQ checklist were followed to ensure standards of research were maintained. Results: 30 participants were recruited for interview. Participants included nursing staff, all grades of doctor and pharmacists. The final audit data set consisted of 100 prescribing episodes: 67 data sets from Site 1 and 33 data sets from Site 2. We developed the IPT from analysis of the local policies for gentamicin prescribing. This allowed us to detail the ‘intended’ process of gentamicin prescribing and identify what appeared to be important contexts, mechanisms and outcomes in this process. The outcomes we were concerned with included: adherence (or not) to protocol and appropriate dosing. The clinical audit found that prescribing at Site 2 adhered more closely to Trust protocol. The mean accuracy of gentamicin prescribing at Site 2 was 78.79 %; Site 1 was 65.67 %. The audit results were found to be significant with a p-value of 0.0038 when a two-tailed T-test was completed in Excel. On review of renal function, seven patients at Site 1 and one patient at Site 2 developed an acute kidney injury (AKI). Of the 8 patients that developed an AKI, 5 had received what was deemed a ‘safe’ (accurate) dose of gentamicin, 2 of the patients had been under-dosed and 1 received too large a dose. With the data from our mixed methods study we were able to refine our IPT and develop the final Programme Theory. The audit data supported the suggested mechanisms. For example: fear of side effects related to gentamicin leads to under-dosing.6,7 All participants at both sites made reference to concerns about gentamicin and the possibility of nephrotoxicity. This leads to cautious prescribing which is more likely to under-dose: Site 1: 24% under-dosed, 10% over-dosed; Site 2: 12% under-dosed 9% over-dosed. The key contexts we noted included: clinician experience; length and prescriptiveness of protocol; availability of patient information; complexity of calculations; involvement of multiple individuals to acquire all relevant data; involvement of different teams. The important mechanisms included: fear of outcomes (such as incorrect dose, damage to kidneys, delay in prescribing in unwell patients); frustration; concern; and confidence. Conclusions: This realist evaluation explored two distinct protocols to prescribing gentamicin in hospital settings. We have identified key contexts (such as properties of the prescribing protocol, the prescribing environment, clinician experience) that trigger hidden mechanisms (uncertainty, fear, confidence and frustration). And these can lead to both the intended outcome of adherence to the prescribing protocol, but also unintended outcomes: intentional deviation from the protocol, unintentional non-adherence and unnecessary gentamicin levels being taken. Our data suggests that a simplified prescribing protocol for gentamicin is better received by those involved in the process of prescribing and leads to both better adherence to protocol and more accurate prescribing. | en_GB |
