Australian cardiac sonographers' use of industry guidelines when performing a transthoracic echocardiogram

Clinical practice guidelines (CPG) are a component of evidence‐based practice allowing standardisation across departments and individuals' skill levels. Australian Cardiac Sonographers (ACS) are not obliged to follow specific CPG when performing a transthoracic echocardiogram (TTE). This research aimed to determine guidelines/workplace protocols ACS follow when performing a TTE, and what attitudes, subjective norms and perceived behavioural controls exist that may prevent adherence to guidelines.


| INTRODUCTION
The primary role of a cardiac sonographer is the performance of a comprehensive transthoracic echocardiogram (TTE). 1 Using a variety of modes including M-mode, two-dimensional (2D) imaging, colour Doppler and spectral Doppler, a TTE provides information on cardiac valves, chambers, great vessels, myocardium and pericardium utilising a series of multiple views. 2 Results can determine cardiac normality or if medical or surgical intervention, chemotherapy regimens and cardiac device insertion, therefore reliable and reproducible results are essential. 3,4 There are no formal national clinical practice guidelines (CPG) for the performance of a comprehensive TTE in Australia.CPG are a component of evidence based practice, allowing evidence to be applied to clinical situations. 5 Adherence to guidelines is a suggested measure of best practice which can improve patient outcomes. 5,6 Existing guidelines include those from the American Society of Echocardiography (ASE) and the British Society of Echocardiography, however, individual practice protocols or cardiologist requests may also be utilised. 2,7 Australian Cardiac Sonographers (ACS) are under no formal obligation to follow a specific guideline in clinical practice. 2,3,6,8 Lack of TTE standardisation has the potential to increase variation in practice, and to affect lifesaving clinical decisions including patient medical and/or surgical management. 3,9 For example, a study comparing the measurements of the aortic root using TTE guidelines based on different age groups revealed different TTE guidelines produce differing and potentially clinically significant measurements. 10 Guidelines have been put in place to standardise practice. Barriers to using guidelines include the assumption that they may not fit the clinical presentation or may de-skill the workforce. However, guidelines have the advantage of providing a holistic approach across multiple departments and skill levels enabling transferability of clinical reasoning. 9 Adherence of ACS to guidelines can be understood by using a behavioural model-the 'Theory of Planned Behaviour' which is used to explain and predict behaviour. 11,12 This model argues a combination of (1) attitudes towards the behaviour under review, (2)

| Survey design
A national survey using purposive sampling of ACS was used with a convergent, parallel design. 21 Online platform SurveyMonkey ® was used. 22 A focus group of six senior and chief ACS were recruited through invitation email to test and refine the survey design. The survey was divided into five sections for analysis including (1) Sociodemographic and professional background characteristics; (2) Attitudes towards TTE guidelines; (3) Subjective norms to guideline adherence; (4) Perceived behavioural controls to following TTE guidelines; and (5) Perceived volitional behaviours to following TTE guidelines. Quantitative and qualitative data were collected, with separate analysis for each methodology.
Software IBM SPSS ® (v 28) was used for statistical analysis of quantitative data. 23 Qualitative data was analysed for themes using NVivo ® software (v12.6) applying a general inductive approach. 24

| Sociodemographic and professional background characteristics
The survey established sociodemographic and professional background information using categorical questions. Fisher's exact test was used to compare categorical data due to some small cell sizes.

| ACS attitudes, subjective norms, behaviours and perceived behavioural controls to TTE guidelines
A five-point Likert ordinal scale was used to assess ACS attitudes, subjective norms, perceived behavioural controls, and perceived volitional behaviour with regard to TTE guidelines and protocols. 25

| Sociodemographic and professional background characteristics
The survey was completed by 131 ACS working in Australia at the time of survey.   Negative themes that were seen to decrease adherence to guidelines included increased experience of sonographer, and a reported lack of consistency to following guidelines across different workplaces.

| ACS perceived attitudes towards using TTE guidelines
Attitudes towards using guidelines when performing a TTE were largely positive ( Figure 4).  peers, and unsupportive subjective norms including a lack of knowledge/interest from cardiologists and management, and a belief that experience negated the need to follow guidelines (Table 2).

| Perceived behavioural controls to following TTE guidelines
Perceived behavioural controls to following TTE guidelines included internal (knowledge and attitude) and external (guideline and environmental) facilitators and barriers. 26 Internal perceived behavioural controls ( Figure 6)   The Theory of Planned Behaviour has previously been used to study behaviour in various fields including education, healthcare and marketing. [27][28][29] It is based on the theory that behaviour of an individual is highly correlated to their intention, which is a summation of attitude (if the behaviour is viewed positively), subjective norm (if others view the behaviour positively), and perceived behavioural control (self-belief in the ability to perform a behaviour). 12 Using this model, an assessment of reported knowledge and behaviours in addition to the three core components of attitude, subjective norms, and perceived behavioural control were performed. While attitudes towards using guidelines when performing a TTE were largely positive, resultant behaviour was not F I G U R E 6 Perceived internal behavioural controls to following transthoracic echocardiogram guidelines F I G U R E 7 Perceived external behavioural controls to following transthoracic echocardiogram guidelines consistent, with 61% of participants reporting measurement or pathology discrepancies compared with TTEs from other practices.
We suggest this deviation may be a consequence of subjective norms and perceived behavioural controls negatively impacting the sonographers' intention to follow guidelines completely and precisely. We propose a national standardisation of guidelines and increased educational initiatives targeting leadership, quality control, and time constraints may improve guideline adherence.

| ACS reported knowledge and behaviours to performing TTEs and following guidelines
Seventy-three percent of participants reported using a combination of guidelines and practice protocols. Subsequently a large proportion

| ACS perceived subjective norms to using TTE guidelines
The Theory of Planned Behaviour demonstrates subjective norms have the weakest correlation with behavioural intention out of the three core components of attitudes, subjective norms and perceived behavioural control. 33 Our study assessed subjective norms as perceived encouragement to adhere to guidelines. We demonstrated that while the majority of ACS felt encouraged to adhere to guidelines by co-workers and cardiologists, a smaller number did not feel encouraged to adhere to guidelines, particularly by management. This indicates a possible obstacle in leadership support in different workplace environments. Themes indicated support was highly workplace dependant with variable knowledge and interest in adherence to guidelines from cardiologists and management.
Senior sonographers were perceived to focus on experience over rigidity.
We suggest any quality improvement initiatives for guideline adherence should involve leadership and senior sonographer groups to improve hierarchical expectations of sonographers to adhere to guidelines.

| CONCLUSION
This study has demonstrated ACS follow a combination of industry guidelines, practice protocols and cardiologist preference when performing a TTE. The most followed guideline is from the ASE,

CONFLICT OF INTEREST
Ann Quinton is an Editorial Board member of Sonography and a coauthor of this article. To minimise bias, they were excluded from all editorial decision-making related to the acceptance of this article for publication.