Factors influencing decisions by critical care physicians to withdraw life-sustaining treatments in critically ill adult patients with severe traumatic brain injury
====================================================================================================================================================================

* Alexis F. Turgeon
* Kristin Dorrance
* Patrick Archambault
* François Lauzier
* François Lamontagne
* Ryan Zarychanski
* Robert Fowler
* Lynne Moore
* Jacques Lacroix
* Shane English
* Amélie Boutin
* John Muscedere
* Karen E.A. Burns
* Donald Griesdale
* Lauralyn A. McIntyre
* Damon Scales
* Francis Bernard
* Janet Yamada
* Janet E. Squires

## Abstract

**BACKGROUND:** Most deaths in critically ill patients with severe traumatic brain injury are associated with a decision to withdraw life-sustaining treatments. We aimed to identify the behavioural determinants that influence recommendations by critical care physicians to consider the withdrawal of life-sustaining treatments in this population.

**METHODS:** We conducted a descriptive qualitative study based on the Theoretical Domains Framework of critical care physicians caring for patients with severe traumatic brain injury across Canada. We stratified critical care physicians by regions and used a purposive sampling strategy. We conducted semistructured phone interviews using a piloted and pretested interview guide. We transcribed the interviews verbatim and verified the content for accuracy. We performed the analysis using a 3-step approach: coding, generation of specific beliefs and generation of specific themes.

**RESULTS:** We recruited 20 critical care physicians across 4 geographic regions. After reaching saturation, we identified 7 core themes across 4 Theoretical Domains Framework domains for factors relevant to the decision to withdraw life-sustaining treatments. Four factors (i.e., clinical triggers, social triggers, interaction with families and intentions with medical decisions) were identified before the decision is made and 3 were identified during the decision-making process (i.e., considerations, priorities and knowledge needs). We identified multiple themes reflecting internal (*n* = 18, 8 Theoretical Domains Framework domains) and external (*n* = 15, 6 Theoretical Domains Framework domains) influences on the decision to withdraw life-sustaining treatments.

**INTERPRETATION:** We identified several core themes and domains considered by critical care physicians in Canada in the decision to withdraw life-sustaining treatments in critically ill patients with severe traumatic brain injury. Future research should aim at identifying the factors influencing surrogate decision-makers in the decision to withdraw life-sustaining treatments in these patients.

Severe traumatic brain injury is a major public health issue, and the leading cause of death and disability among people under 45 years of age.1 Mortality rates remain high, and a substantial proportion of survivors have severe neurologic sequelae despite improved patient management and the development of evidence-based practice guidelines.2–4 Data correlating early assessments and neurologic prognosis in this patient population are scarce, of limited clinical usefulness and variable among physicians.2,3,5 In the absence of conclusive evidence supporting the available prognostic models, families and medical teams are faced with making life-altering, level-of-care decisions in these patients that may include the withdrawal of life-sustaining treatments. The consequences of these decisions for the lives of patients and families are immeasurable. Concerns have been raised over the years about clinicians making decisions about withdrawal of life-sustaining treatments in the absence of appropriate prognostic information in previously healthy patients.6–8

We previously documented a significant variation in mortality following severe traumatic brain injury across trauma centres in Canada, including marked variation associated with the decision to withdraw life-sustaining treatments.9 Moreover, of all deaths after withdrawal of life-sustaining treatments following traumatic brain injury, half occurred during the first 3 days of care, which many physicians consider to be premature for making such decisions.5,9 Although critical care physicians commonly lead end-of-life discussions with caregivers based on perceived prognosis, clinicians often disagree when evaluating the prognosis of critically ill patients.5

Little is known about factors influencing the evaluation of prognosis and the shared decision to withdraw life-sustaining treatments made by physicians and families or surrogate decision-makers for patients with severe traumatic brain injury. The recent advent of organ donation programs after cardiac arrest following withdrawal of life-sustaining treatments that target populations with severe neurologic injuries (including traumatic brain injury) has added an ethical perspective to these difficult decisions, especially considering that the physicians involved in the care of these patients are often the same ones who are involved in the recognition and care of organ donors.10 This phenomenon underscores the need for a better understanding of the determinants of end-of-life decisions by physicians and families of patients with severe traumatic brain injury.

The purpose of our study was to identify the behavioural determinants that influence recommendations by critical care physicians to withdraw life-sustaining treatments in patients with severe traumatic brain injury.

## Methods

### Study design and participants

We conducted a descriptive qualitative study using semistructured interviews with critical care physicians who care for patients with severe traumatic brain injury across Canada. To identify our study population, we developed a comprehensive list of critical care physicians working in all Canadian Level 1 trauma centres (tertiary care facilities) through critical care department or service leads and trauma directors at each centre that cared for adult patients. We stratified critical care physicians by geographic and demographic regions: Eastern Canada (provinces of Newfoundland and Labrador, Nova Scotia, New Brunswick and Prince Edward Island), Quebec, Ontario and Western Canada (provinces of Manitoba, Saskatchewan, Alberta and British Columbia).

We used a purposive sampling strategy to recruit participants. We generated a random list of potential participants for each of the 4 regions and contacted the first name on the list for each region. We selected the subsequent potential participants from these random lists according to regular intervals, known as periods. One of the investigators (A.T.) asked selected potential participants via email about their interest in participating in the study. If a potential participant refused to participate or did not reply after 2 reminders, the next potential participant in the list corresponding to the geographic zone was solicited. Selected potential participants who were interested in participating were instructed to contact a member of our research team (K.D.).

### Data collection

We conducted semistructured phone interviews with critical care physicians guided by an interview guide. The interview guide contained open-ended questions with standard prompts available to the interviewer (K.D.) when needed and was informed by the Theoretical Domains Framework11,12 (Appendix 1, available at [www.cmaj.ca/lookup/suppl/doi:10.1503/cmaj.190154/-/DC1](http://www.cmaj.ca/lookup/suppl/doi:10.1503/cmaj.190154/-/DC1)). The Theoretical Domains Framework is a behaviour change framework from the field of health psychology developed jointly by health psychology theorists, health services researchers and health psychologists. It comprises 14 theoretical domains derived from 128 constructs from 33 different theories of health, behavioural and social psychology that explain changes in health-related behaviour.11,12 Considering the purpose of our study, we combined 2 Theoretical Domains Framework domains resulting in 12 domains versus 14 domains: “beliefs about capabilities” and “optimism” were combined as were “intentions” and “goals.” We piloted and pretested the interview guide with 5 critical care physicians and modified it accordingly. All interviews were conducted in English and audio recorded.

### Data analysis

We transcribed the interviews verbatim, and the interviewer (K.D.) verified the content for accuracy. We removed any information that could potentially identify the participant from the transcripts. We performed the analysis using a 3-step approach as follows.

#### Step 1: coding

Using thematic content analysis,13 2 study team members (K.D., J.Y.) independently coded the content of the interview transcripts into the 12 Theoretical Domains Framework domains that were proposed in the interview guide. These 2 team members met weekly to compare their coding and reach consensus on the Theoretical Domains Framework domain corresponding to each code generated. A third coder was involved to resolve disagreements (J.E.S).

#### Step 2: generation of specific beliefs

A specific belief refers to a collection of participant responses with a similar underlying theme that suggests a problem or influence on the target behaviour.14 Each code was rewritten as a specific belief by 1 team member (K.D.) and verified by the second team member (J.Y.). A third coder was involved to resolve disagreements (J.E.S).

#### Step 3: generation of specific themes

Similar specific belief statements from step 2 were then grouped into common themes. Themes represented a higher-level categorization of the data, with each theme subsuming multiple belief statements. The themes were our main unit of analysis; they were analyzed to identify which themes were part of the decision-making process, if they were internal or external influences on the decision, and if they affected a certain phase of the decision to withdraw life-sustaining treatments (i.e., before the decision is made or during the decision-making process).

We used NVivo software (QSR International) to code the analyses.

#### Sample size

Our sample size was based on the conduct of interviews within each of the 4 Canadian regions until data saturation was achieved.15 We defined saturation as when 3 consecutive interviews were conducted with no new themes emerging. We achieved saturation after conducting 20 interviews.

### Ethics approval

This study was approved by the Ottawa Hospital Research Institute Research Ethics Board (protocol 2015051701H).

## Results

We approached 104 critical care physicians to recruit 20 participants between November 2015 and March 2016. The distribution of participants across the 4 Canadian geographic regions was similar through the use of our sampling strategy. Most participants were male (*n* = 16, 80.0%), born in Canada (*n* = 12, 60.0%), had 10 years of experience or less (*n* = 11, 55.0%), and spent between 10 and 20 weeks per year in the intensive care unit (ICU; *n* = 17, 85.0%) (Table 1). A total of 499 specific belief statements were generated from the 20 interviews. The number of specific beliefs varied across the 12 Theoretical Domains Framework domains, ranging from a low of 17 beliefs (intention domain) to a high of 78 beliefs (social influences domain). Beliefs were merged to create common themes that are described next.

View this table:
[Table 1:](http://www.cmaj.ca/content/191/24/E652/T1)

Table 1: 
Demographic characteristics of the participants

### Factors considered when deciding to withdraw life-sustaining treatments

We identified 7 core themes across 4 Theoretical Domains Framework domains for factors considered by critical care physicians to be relevant to the decision to withdraw life-sustaining treatments (Table 2) in patients with severe traumatic brain injury. Four of these themes occurred as background factors, meaning that they occurred before making the decision, whereas 3 occurred during the decision-making process itself. Important background factors that emerged included a wide variety of triggers, both clinical (e.g., clinical examination and clinical significance of the injury) and social (e.g., family request to withdraw life-sustaining treatments), as well as a variety of intentions with respect to the patient and their family (e.g., letting the patient’s wishes guide the decision) and the decision to withdraw life-sustaining treatments (e.g., “take my time”). Additional factors were found to be important during the actual act of making the decision, including nature and degree of the injury, priorities (e.g., taking our time) and knowledge needs (e.g., prognosis for patients with severe traumatic brain injury).

View this table:
[Table 2:](http://www.cmaj.ca/content/191/24/E652/T2)

Table 2: 
Factors considered by critical care physicians in deciding to withdraw life-sustaining treatments in patients with severe traumatic brain injury

### Internal and external influences

Eighteen themes across 8 Theoretical Domains Framework domains and 15 themes across 6 Theoretical Domains Framework domains emerged that reflect internal (e.g., experience in making decisions to withdraw life-sustaining treatments) and external (e.g., legislation and culture of patients in Ontario affect how decisions are made about withdrawal of life-sustaining treatments) influences, respectively, on decisions by critical care physicians to withdraw life-sustaining treatments in critically ill patients with severe traumatic brain injury. We found less consistency among physicians with respect to the external influences in comparison with the internal influences that were identified: 26.7% (4 of 15) of the external influences compared with 61.1% (11 of 18) of the internal influences were reported by 50% or more of the physicians we interviewed. Of the 15 themes with the highest frequencies, 6 (5 internal and 1 external) reflected background influences, whereas the remaining 9 reflected influences that occur during the decision-making process (Table 3, Table 4).

View this table:
[Table 3:](http://www.cmaj.ca/content/191/24/E652/T3)

Table 3: 
Themes identified as internal influences on critical care physicians when deciding to withdraw life-sustaining treatments in patients with severe traumatic brain injury

View this table:
[Table 4:](http://www.cmaj.ca/content/191/24/E652/T4)

Table 4: 
Themes identified as external influences on critical care physicians when deciding to withdraw life-sustaining treatments in patients with severe traumatic brain injury

### Conflicting beliefs

We identified several potentially conflicting themes. We found disagreement between a clinician’s desire to respect a patient’s wishes and his or her need for more time to assess prognosis better, or to respect the patient’s autonomy and social justice to manage resources adequately in the context of limited resources. The experience of the physician (or lack of experience) and the need for better prognostic models were also raised as important themes. Although clinicians want to lead this discussion and direct the decision (based on their experience and knowledge about the final prognosis), they also want to consider fully what the previous wishes of the patient were and make a recommendation based on their best judgment as to how to harmonize the influence of each of these factors.

### Very strong beliefs that may affect behaviour or decision-making

The need for better prognostic models was identified as a very strong factor in the decision to withdraw life-sustaining treatments. Clinicians’ emotions, anxiety about validity of their prognosis and making the right recommendation when the stakes are so high (e.g., young patients and “miracle cases” from other colleagues) were also important reported factors. Diverging views among the clinical team will delay the withdrawal of life-sustaining treatments until consensus is obtained. Better prognostic models would help address these issues, as per respondents.

Overall, the main domains involved in decision-making for physicians across Canada were memory, attention and decision process; intention; goals; and knowledge. Internal influences involved in the decision were consistent among critical care physicians who identified themes reflecting background influences. The domains affected by these internal influences were skills, social and professional roles and identities, reinforcement, emotion, social influences, beliefs about capabilities and beliefs about consequences. However, the external influences involved in the decision were not consistent among participants. The domains affected by these external influences were social and professional roles and identities; environment, context and resources; skills; behavioural regulation; and beliefs about consequences.

## Interpretation

We identified several core themes derived from domains of the Theoretical Domains Framework that are considered by critical care physicians in Canada in the decision to withdraw life-sustaining treatments in critically ill patients with severe traumatic brain injury. Memory, attention and decision process, intention, goals, and knowledge were the main domains involved in the decision-making for physicians across Canada. The Theoretical Domains Framework can help explain difficult decision processes such as level-of-care decisions in critically ill patients with severe traumatic brain injury.

Our study provides insight into how to improve decision-making in this very complex and emotionally charged clinical situation. The Theoretical Domains Framework commonly has been used in health care research to identify barriers and facilitators of the implementation or not of an intervention or a process of care to change behaviours.16–19 In our study, we used this framework to identify the behavioural determinants that influence physicians’ recommendations to withdraw life-sustaining treatments with the intent of identifying the targets for a future intervention to improve decision-making counselling among physicians.20 In particular, physicians in our study seemed to point toward the need for better knowledge (e.g., prognostic evidence to help guide their recommendations), for better experience and training to make recommendations, for more time to make better prognostic estimations (including time to create consensus among involved consultants) and eventual recommendations to patients’ surrogate decision-makers, and for better tools to integrate patient’s values and preferences into decision-making.

Common elements of the decision-making leading to the withdrawal of life-sustaining treatments identified in our study have also been identified in other populations such as critically ill extremely premature neonatal patients,21 critically ill patients with stroke and frail older adults.22,23 Critical care physicians in these fields state that poor prognosis, patient preferences and quality of life are important determinants in recommending the withdrawal of life-sustaining treatments. Similar to the extremely premature neonatal population whose premature delivery was not expected or impossible to prevent, younger patients with severe traumatic brain injury are at a time in their lives when they are for the most part free of major comorbidities and have the promise of continuing to live a high-quality life before their injury. Once their catastrophic injuries occur, the importance of adequate prognostication becomes essential in both populations. The extremely premature neonatal population risk living with multiple severe comorbidities.21 This contrasts with decision-making for the younger population with severe traumatic brain injury: it is influenced by a different set of ethical, social and medical issues.

In the population of older adults who are critically ill, decisions are not based only on prognosis and quality of life but are also very much influenced by the quality of dying and the strong aversion to suffering at end of life.22 In this population, where functional decline can already be occurring before admission to the ICU and most likely will be accelerated by their stay in the ICU, decision-making can be facilitated by a higher prevalence of advance directives to help guide surrogate decision-makers in decisions to withdraw life-sustaining treatments. We found that many clinicians struggle to make recommendations to withdraw life-sustaining treatments because they often face uncertainty when trying to match the preferences of the surrogate decision-makers on quality of life for the patient and how precisely physicians can predict a reliable functional prognosis. However, all respondents identified the influence of the patient and the family as an important factor in these decisions. These findings are reassuring but challenging when facing uncertainty. Most (90%) mentioned that past experiences influence how they approach and make decisions.

Overall, the lack of reliable prognostic models seems to be a substantial barrier for physicians when involved in a decision to withdraw life-sustaining treatments in patients with severe traumatic brain injury. We found an important unmet need for better prognostic models to help reduce uncertainty, and to decrease physicians’ negative emotions and anxiety about making better recommendations to withdraw life-sustaining treatments. Only 1 respondent out of 4 felt that adequate training during fellowship had helped them be able to make these decisions, which suggests that the training curriculum in critical care medicine could be improved.

### Limitations

Our study has some limitations. In most health care systems, as in Canadian ICUs, the decision to withdraw life-sustaining treatments is a shared decision made by bedside critical care physicians and surrogate decision-makers. In our study, we did not interview family caregivers or surrogate decision-makers involved in these decisions, nor did we consult other health care professionals and members of the critical care team (i.e., nurses, spiritual support caregivers and social workers) who could also offer a rich perspective to the factors influencing decision-making about withdrawal of life-sustaining treatments in patients with severe traumatic brain injury. Our decision was deliberate because we chose to focus on only critical care physicians considering their pivotal role in family meetings and in these decisions.

The results of our study may not apply outside the Canadian context; critical care physicians from other countries, health care systems, societies and communities may have other perspectives with a different impact in the context of withdrawal of life-sustaining treatments.

Our interviews were not conducted in real time with physicians actually engaged in making recommendations about the withdrawal of life-sustaining treatments, which may expose our results to a potential recall bias. Respondents may have put more emphasis on exceptional situations rather than on more common ones considering that we may have a better recall of important events.

Our study was not designed to understand the determinants that influence surrogate decision-makers. Future research using direct observation of physicians and surrogate decision-makers for patients could help us deepen our understanding of the barriers and facilitators of making recommendations about the withdrawal of life-sustaining treatments and how interventions could improve the experience for surrogate decision-makers.

### Conclusion

Our study identified clinically useful information about the processes surrounding level-of-care decisions for the early care of critically ill patients with severe traumatic brain injury. Identifying clear determinants involved in this process should help to improve how physicians make recommendations to withdraw life-sustaining treatments in this population. Our study has implications for the care of critically ill patients with severe traumatic brain injury and can inform policy implementation to improve our approach to the evaluation of prognosis and level-of-care decisions in this population. Future research should aim at identifying the factors influencing surrogate decision-makers in the decision to withdraw life-sustaining treatments in critically ill patients with severe traumatic brain injury.

## Acknowledgements

The authors thank Olivier Costerousse and Marjorie Daigle for their administrative help. This study was developed with the Canadian Critical Care Trials Group (CCCTG) and the Canadian Traumatic Brain Injury Research Consortium (CTRC). The authors thank the CCCTG and the CTRC Grants and Manuscripts Committees for the critical review of the manuscript.

## Footnotes

*   Visual abstract available at [www.cmaj.ca/lookup/suppl/doi:10.1503/cmaj.190154/-/DC2](http://www.cmaj.ca/lookup/suppl/doi:10.1503/cmaj.190154/-/DC2)

*   **Competing interests:** None declared.

*   This article has been peer reviewed.

*   **Contributors:** Alexis Turgeon had the original idea for this work. Alexis Turgeon, Patrick Archambault, François Lauzier, François Lamontagne, Ryan Zarychanski, Robert Fowler, Lynne Moore, Jacques Lacroix, Shane English, Amélie Boutin, John Muscedere, Karen Burns, Donald Griesdale, Lauralyn McIntyre, Damon Scales, Francis Bernard and Janet Squires developed the protocol. Kristin Dorrance, Janet Squires and Alexis Turgeon developed the study instrument and interview framework. Kristin Dorrance performed the interviews. Kristin Dorrance, Janet Yamada and Janet Squires coded the interviews. Alexis Turgeon, Kristin Dorrance and Janet Squires wrote the first draft of the manuscript. All of the authors participated in the interpretation of the data, revised the manuscript critically for important intellectual content, gave final approval of the version to be published and agreed to be accountable for all aspects of the work.

*   **Funding:** This research was supported by the Fonds de la Recherche du Québec — Santé (FRQS; grant no. 24792) and by the Canadian Institutes of Health Research (CIHR; Foundation Scheme no. 354039). Alexis Turgeon holds the Canada Research Chair in Critical Neurology and Trauma. François Lauzier, François Lamontagne and Lynne Moore received research salary awards from the FRQS. Patrick Archambault received an embedded clinician researcher salary award from the CIHR. Amélie Boutin received a training award from the CIHR when this work was performed. Alexis Turgeon, François Lauzier and Lynne Moore are supported by the Traumatology Research Consortium (FRQS). The Canadian Critical Care Trials Group is funded by a Community Development Grant from CIHR, and the Canadian Traumatic Brain Injury Research Consortium is funded by a Team Grant from CIHR.

*   **Data sharing:** Individual participant data may not be available according to the consent obtained. However, any secondary use of the data can be submitted to the study steering committee for evaluation.

*   Accepted May 6, 2019.

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