Anesthesiologists’ and surgeons’ perceptions about routine pre-operative testing in low-risk patients: application of the Theoretical Domains Framework (TDF) to identify factors that influence physicians’ decisions to order pre-operative tests

Pre-operative tests are ordered to aid in the management of surgical patients. These pre-operative tests provide information about the function of the biological systems that may not be directly affected by the surgical condition, but may be relevant to the perioperative course[1]. However, many pre-operative tests are routinely ordered for apparently healthy patients without any clinical indication, and the subsequent test results are rarely used[2]. In addition, unnecessary testing may lead physicians to pursue and treat borderline and false-positive laboratory abnormalities[3]. A randomized control study (RCT) of over 19,000 cataract patients found no benefit to routine pre-operative medical testing when stratified according to age, gender, or race of the patient, and most abnormalities in laboratory values could be predicted from patient’s history and physical exam[4]. Further, Chung et al. conducted an RCT of routine pre-operative testing in 1,057 ambulatory patients where one arm received pre-operative tests ordered according to the Ontario Pre-operative Testing Grid[5] and the other received no pre-operative tests routinely ordered for anesthesia management[6]. They reported no significant difference between rates of perioperative adverse events and the rates of adverse events 30 days after surgery between groups[6].

The Canadian Anesthesiologists’ Society (CAS) has published guidelines to aid pre-admission teams about the appropriateness of certain tests prior to surgery[7]. They advocate that investigations should not be ordered on a routine basis, but should be based on the patient’s health status, drug therapy, and with consideration to the proposed surgical intervention[7]. However, in a study conducted by Hux et al. that looked at patterns of pre-operative chest x-rays and electrocardiogram—two tests commonly ordered routinely for anesthesia management—use in Ontario surgical patients, they reported considerable variation in testing rates in low-risk procedures across the province as well as within institutions[8]. In 50 Ontario hospitals, for low-risk (outpatient) procedures (cystoscopy, cataract removal, laparoscopic cholescystectomy, hysterectomy), hospital-specific rates of patients receiving chest x-ray, electrocardiogram, or both ranged from less than 1% to 98%[8]. These findings suggest that factors other than evidence of patient benefit may influence test ordering behaviour.

Failure to convert recommendations into practice is often not related to the content or quality of the guideline but to difficulties in changing established behaviours of the clinicians and institutions[9]. Canadian surgical patients encounter a number of healthcare providers responsible for their experience in the healthcare system including the family physician writing the referral, the attending surgeon, the attending anaesthesiologist, nursing staff, and the myriad of professionals in the pre-admissions clinic. Translating guidelines into clinical practice is notoriously difficult when one healthcare professional has decision-making autonomy; it can be even more so when a group of professionals are responsible, as is the case with pre-operative test ordering. While the guidelines for pre-operative testing are recommendations for anaesthesiologists, other clinicians can and do order pre-operative tests. Bryson reported that surgeons were responsible for 80% of the test ordering that were in non-compliance with the Ontario Pre-operative Testing Grid at the Ottawa Hospital[10]. When many groups of professionals can be the potential target of behaviour change interventions, understanding the thoughts and opinions of the key clinical decision makers about the behaviour in question becomes important. However, much of the work examining health practitioner behaviour change has, to date, been largely atheoretical[11‐14]. Using theory for identifying determinants of behaviour and selecting interventions can increase the likelihood of the complex interventions being appropriate[15]. Empirically-supported theories of behaviour change may thus inform attempts to change test-ordering behaviour. Establishing a better theoretical understanding of healthcare professional behaviours and their perceptions of team behaviours may increase the likely success of interventions to change clinical practice.

Psychological theories have long been used to understand, predict, or generate behaviour change in healthcare providers[11, 16‐19]. Commonly, researchers have tested a single or small number of theories. As a result, only a small range of the potential influences on behaviour are tested. Such studies may be uninformative if the key determinants of the behaviour under question are not represented in the tested theories. Currently, there is little rationale to guide choice of potentially relevant theories. In an attempt to address these problems, Michie et al.[20] applied a systematic consensus approach to develop a framework grounded in psychological theory that simplifies theories relevant to behaviour change. The consensus identified 12 theoretical domains from 33 theories and 128 constructs that may explain health-related behaviour change. The Theoretical Domains Framework (TDF) can be used to inform the choice of potential behaviour change techniques to develop interventions as well as to investigate determinants of behaviour[20].

In this study, we used the TDF to systematically examine the beliefs of anaesthesiologists and surgeons about the use of pre-operative testing routinely ordered for anesthesia management in healthy patients undergoing low-risk surgical procedures. This article is one in a series of articles documenting the development and use of the Theoretical Domains Framework (TDF) to advance the science of implementation research[21‐24]. Greater detail about the TDF can be found in the introductory article of this series[23].

This study applied the TDF[20] to help understand the influences of pre-operative test ordering practices for anesthesia management in healthy patients by anesthesiologists and surgeons. The results show that the most frequently mentioned influences on the clinicians’ test ordering practice were categorised primarily in the Social/professional role and identity, Beliefs about capabilities, Beliefs about consequences, Environmental context and resources, and Social influences domains, and centred around two key issues. First, the lack of clarity by hospital management and lack of written policies as to who was ultimately responsible for ordering the tests (Social/professional role and identity, and Environmental context and resources) is a considerable factor influencing whether or not they order routine pre-operative tests. Respondents reported that hospitals commonly either failed to identify which group was specifically responsible for test ordering or identified surgeons as the group responsible for test ordering. Further, the existence of hospital directives varied from hospital to hospital throughout the province (Environmental context and resources). The finding that surgeons often order pre-operative tests according to hospital policies seems counterintuitive because the Canadian Anesthesiologists’ Society is the professional body making the recommendations and state that policies regarding pre-anesthetic assessment should be established by the department of anesthesia[7]. Yet, the anesthesiologists and surgeons interviewed report this finding as accurate and is further supported by evidence documented by Bryson et al.[29]. The likelihood that an alternative professional group would review another’s guidelines is rare because they struggle to keep up-to-date with their own ever-changing evidence-based practice. So how do we ensure that those responsible obtain the best and most current evidence? A directive by hospital management that is supported by the professional groups involved, as to which group holds the role and responsible for ordering the tests required for anesthesia management would likely reduce confusion and encourage greater consistency in test ordering practices.

Second, evidence of the inter-professional influences among the attending surgeon performing the surgery, the anesthesiologist at pre-admission ordering the tests, and attending anesthesiologist providing intraoperative care was reported by the vast majority of respondents (Social/professional role and identity, Beliefs about capabilities, Belief about consequences, and Social influences). The lack of clarity about who is responsible for routine test ordering appears to lead to a propensity to order tests ‘ just in case’ they are expected by another colleague. A surgeon may order the tests ‘ in case’ the attending anesthesiologist needs it and in hopes that the patient will move smoothly through the pre-admission assessment process. The anesthesiologist who sees the patient prior to the surgery orders the tests ‘ in case’ the attending anesthesiologist needs them and could not cancel tests ordered by the surgeon because they have not identified the reason for ordering the tests. Furthermore, the anesthesiologists interviewed reported they seldom reviewed test results when caring for low-risk patients in the operating room. The interesting thing about the team influence is that although anesthesiologists and surgeons greatly influence whether pre-operative test are ordered by another team member, these clinicians rarely have direct contact with one another and communication is difficult. A study by Lingard et al. examined intraoperative communication in a surgical team comprising surgeons, nurses, anesthesiologists, and trainees[30]. They found marked differences in the professionals’ perceptions around issues of role authority, motivation, and value with respect to communication among team members. Although their study looked at four professional groups, their findings are consistent with ours in identifying a problem in the lack of clarity relating to roles of surgeons and anesthesiologists. They suggest that communications of these team members are probably motivated by some combination of concern for the patient, the day’s schedule, ethical issues, economic implications, and many other factors[30], an idea that is reflected in our finding of professionals ordering test just ‘ in case’ the tests are needed. Further, communication with respect to pre-operative testing is additionally complicated by the surgeons’ and anesthesiologists’ separation by time and space.

This study is one of the first to attempt to examine why anesthesiologists and surgeons order routine pre-operative tests when no clinical indicators exist. There has been a large body of work reporting pre-operative testing practices[2, 4, 6, 10, 31‐33]. However, few attempt to explain why clinicians do one thing when the guidelines recommend another with respect to test ordering for anesthesia management[7]. A systematic review by Munro et al. reported that the value of pre-operative ECGs in predicting postoperative cardiac complications seems to be very small, and the indirect evidence suggests that routinely recorded pre-operative ECGs as a baseline measure are likely to be of little or no value[34]. Further the anesthesiologists and surgeons interviewed appear to lend credence to this report. Yet, reports continue to document unnecessary routine test ordering[2, 4, 6, 10, 31‐33], and we have attempted to ask those clinicians involved why unnecessary tests for anesthesia management continue to be ordered. Bryson et al. was the only paper reviewed to suggest a need to change ‘ established behaviour’ that should include not only anesthesiologists but surgical colleagues and clinic personnel[10]. By examining the views of the clinical decision makers (anesthesiologists and surgeons) in a theory-based systematic manner, we have identified the theoretical domains we propose best predict pre-operative test ordering for anesthesia management when assessing healthy patients undergoing low-risk surgeries.

Seven domains were considered potentially important for changing test-ordering behaviour (Social/professional role and identity, Beliefs about capabilities, Beliefs about consequences, Environmental context and resources, Social influences, Behavioural regulation, Nature of the behaviour), while five were consistently identified as not relevant (Knowledge, Skills, Emotion, Motivation and goals, and Memory, attention and decision processes). Of the seven identified the five that appeared to be the most influential, based on the frequency of utterances coded and content of the responses, were Social/professional role and identity, Beliefs about capabilities, Beliefs about consequences, Environmental context and resources, and Social influences. The TDF is a relatively new framework that attempts to help understand clinical behaviour from a psychological perspective. Previous attempts to understand clinicans’ behaviour has either been atheoretical[11‐14] or have used a limited number of theories[35‐37] with varying effectiveness. Ideally, researchers should have ready access to a definitive set of theoretical explanations of behaviour change and a means of identifying which are relevant to particular contexts[20]. The TDF allow for a categorisation of respondents’ views in a theoretically-based systematic way that attempts to encompass a broad range of psychology theories without favouring a specific one.

While this study has provided valuable insight into the factors that may influence routine test ordering practices, there were several limitations. It is possible that saturation could have been prematurely reached if participants recommended interviewing others with similar opinions. In an attempt to avoid this, one of the criteria used in our purposive sampling was to ask the participants to recommend additional anesthesiologists with differing opinions. Subsequently, our results show that there was evidence of differing opinions from the anesthesiologists and surgeons about order test routinely ordered for anesthesia management.

Identification of themes does not provide evidence of the actual influences on clinical practice. These are merely clinicians’ views about what might influence their test ordering behaviour. Although interview studies are required in the exploratory stages of research in this field, different research designs would be required to establish which of these factors could be key to changing practice.

In this study the interview guide used a combination of questions that elicited descriptive and diagnostic responses (e.g., ‘ What thought processes might guide your decision to order pre-operative test for a patient having a low-risk surgery?’ is descriptive, whereas ‘ Are you confident that you are able to perform a pre-operative evaluation for a low-risk surgery without pre-operative tests?’ is diagnostic). It thus required further interpretation by the research team to decide whether a descriptive response represented a barrier to changing practice. For studies that use the TDF for problem analysis, it may be preferable to use more questions of the diagnostic kind.

Our study has shown that in various hospitals across the province of Ontario anesthesiologists are often not the professional responsible for ordering the pre-operative tests, even though the Canadian Anesthesiologists’ Society has published guidelines directing this aspect of perioperative care. Interviewing surgeons in addition to anesthesiologists strengthened our findings because it gave us the perspectives from both key professional groups responsible for ordering pre-operative test. It also identified the link between attending surgeon, assessing anesthesiologist, and attending anesthesiologist as an important social influence of pre-operative test ordering. Additional strength in our findings was that even though the two groups differ in their role in the care of patients, their responses around pre-operative test order practice largely converged. Both groups throughout the province repeatedly identified the same issues of concern. Recently, there have been a numbers of studies examining the inter-professional dynamics within a team of healthcare providers[30, 38‐41] but further work is necessary to better understand the inter-professional dynamics of a healthcare team. Developing an intervention that would take into consideration the roles of all personnel involved in the care of a patient undergoing low-risk surgery has the greatest likelihood of being successful and should be developed using the domains identified in this study; in particular social/professional role and identity, beliefs about consequences, environmental context and resources and social influence.

This study is one of the first to attempt to examine why anesthesiologists and surgeons order routine pre-operative tests. Our results identified potential influences, as defined by the TDF, upon test ordering behaviour of anaesthesiologists and surgeons when clinical indictors are not present. It offers a possible explanation to the test ordering differences reported by Hux et al.[8] and may help explain why routine tests are continually ordered when evidence shows their lack of value for perioperative management[2, 4, 29, 32]. Our findings can be used to develop a confirmatory predictive study to further explore determinants of routine pre-operative test order practice by developing a questionnaire for the key professionals based on the domains and content of the interviews. In addition, the results can be used to develop an intervention using intervention mapping directly from the domains[42]. By using the TDF, our study provides a theory-driven basis to identify predictors of clinician behaviour as well as generate possible interventions for the reduction of unnecessary pre-operative tests routinely ordered for anesthesia management.

JMG holds a Canada Research Chair in Health Knowledge Transfer and Uptake. The Canada PRIME Plus team is an international collaboration of researchers consisting of health services researchers, health psychologists and statisticians.