Weaning from mechanical ventilation is influenced by patient, clinician, and organizational factors.
To identify factors that may influence weaning and adoption of weaning strategies and tools, clinicians’ perceptions of weaning strategies, and weaning experiences of patients and patients’ families.
A scoping review of indexed and nonindexed publications (1990–2012) was done. Qualitative studies of health care providers, patients, and patients’ families involved in weaning were included. Two investigators independently screened 8350 publications and extracted data from 43 studies. Study themes were content analyzed to identify common categories and themes within the categories.
The study sample consisted of nurses in 15 studies, nurses and patients in 1 study, various health care providers in 11, patients in 10, and physicians in 4. Categories identified were as follows: for nurses, role or scope of practice, informing decision making, and influence on weaning outcome; for health care providers, factors influencing weaning decisions or use of protocols, role or scope of practice related to weaning, and organizational structure or practice environment; for patients, experience of mechanical ventilation and weaning, experience of the intensive care environment, psychological phenomena, and enabling success in weaning; and for physicians, tools or factors to facilitate weaning decisions and perceptions of nurses’ role and scope of practice.
Important issues identified were perceived importance of interprofessional collaboration and communication, need to combine subjective knowledge of the patient with objective clinical data, balancing of weaning systematization with individual needs, and appreciation of the physical and psychological work of weaning.
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List 3 key factors that influence ventilator weaning.
Define a scoping review.
Describe the steps in conducting a scoping review.
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Weaning from mechanical ventilation is a time-sensitive and complex intervention influenced by patient, clinician, and organizational factors and by clinical interventions such as sedation management, delirium prevention, and early mobilization. Research since the early 1990s has shown that optimizing the weaning process involves 3 key ingredients, all of which should occur without unnecessary avoidable delays: recognition of weaning readiness, adjustments in mechanical ventilation to promote spontaneous breathing, and recognition of readiness for extubation and cessation of mechanical ventilation. Despite this knowledge, weaning remains suboptimal at times, and research continues to focus on ways to improve the weaning process and related outcomes for patients.1
Most patients are easily and successfully weaned from mechanical ventilation on the first attempt.2 However, even for these easy-to-wean patients, organizational and clinician factors such as staffing levels, skill mix, experience, and decision-making hierarchy influence the weaning process and can delay weaning and extubation. Such delays may result in prolonged duration of mechanical ventilation and stay in the intensive care unit (ICU) and increased costs.3 Approximately 30% of patients treated with mechanical ventilation experience difficult or prolonged weaning.4 For these patients, similar organizational and clinician factors influence the duration and success of weaning. Because of the risk of further prolongation of mechanical ventilation, reintubation, and increased mortality,5,6 identification of potentially modifiable factors that cause delays in weaning, unsuccessful weaning trials, and unsuccessful attempts in extubation is needed.
An important step in ascertaining patient, clinician, and organizational factors that influence weaning is obtaining the views and perceptions of clinicians, patients, and patients’ families who experience the process. Using qualitative study methods to examine patients’ experiences in weaning can provide further understanding of the causes of unsuccessful weaning and indicate strategies to prevent unsuccessful attempts. Patients’ family members, who know patients better than any health care provider does and who spend time at the bedside observing interactions between patients, the ventilator, and clinicians, can offer important insights.
About 30% of patients using a ventilator experience difficult or prolonged weaning.
Therefore, we used a rigorous scoping review to map recent publications on contextual factors (organizational, professional, behavioral, attitudinal) that influence processes related to weaning, clinicians’ perceptions and attitudes toward tools to promote timely weaning, and weaning experiences of patients and patients’ family members. The purpose of the review is to inform clinical practice, policy development, and future research to optimize the weaning process.
A scoping review was used to examine the extent, range, and nature of qualitative research on patient, clinician, and organizational factors that might influence weaning. The purpose of scoping studies is “to map rapidly key concepts underpinning a research area and the main sources and types of evidence available, . . . especially where an area is complex or has not been reviewed comprehensively before.”7 (p194) Thus, the objective was not to synthesize research findings in depth but to map the field of study to facilitate visualization of the range of material available.8 The results can inform future decision making on the need for a metasynthesis or further research. The original framework put forward by Arksey and O’Malley8 and refined by Levac et al9 (Figure 1) was used for the study.
The 3 study questions were as follows:
What factors (organizational, professional, behavioral, attitudinal) influence the weaning process?
What are health care providers’ (nurses, physicians, respiratory therapists) perceptions of and attitudes toward strategies for optimizing weaning, including adoption, implementation, and effectiveness of strategies such as weaning protocols, guidelines, and weaning teams?
What are the weaning experiences of patients and patients’ family members?
Qualitative studies of health care personnel who provided care during the weaning process and of patients and patients’ family members who experienced weaning in the ICU (adult and children) were included in the review. Typical of scoping reviews, the inclusion criteria were based on the relevance of the studies rather than on the quality. Empirical studies (primary studies or part of larger, mixed-method studies) were included if qualitative methods were used. Study types included participant and nonparticipant observation, interviews (1 on 1 or focus group), and case studies underpinned by theoretical frameworks such as phenomenology, ethnography, grounded theory, action, and narrative research. Quantitative surveys that included content analysis of open-ended questions were included. Studies with quantitative designs (randomized and controlled clinical trials, cohort and case-control studies), commentaries, editorials, and individual opinion papers were excluded.
Indexed and nonindexed publications and gray literature (material with no bibliographical information) for January 1, 1990, to August 31, 2012, were reviewed. Studies were not excluded on the basis of language. Electronic databases included Medline, CINAHL, EMBASE, ISI Web of Science and Conference Proceedings, and PsycINFO. Gray literature sources included BIOSIS, Scirus, Scientific Web-Plus, ScienceWatch, US Department of Health and Human Services (National Guideline Clearing House, Annotated Bibliographies, Expert Commentaries, Guideline Syntheses), Google, MSN, ProQuest Dissertations and Theses, ProQuest Nursing and Allied Health Source, and ProQuest Biological Science. The website www.healthtalkonline.org was searched to identify gray literature on patients’ experience. Additional sources included websites of relevant professional societies and conference abstracts from annual meetings of the Society of Critical Care Medicine, American Association of Critical-Care Nurses, Australian and New Zealand Intensive Care Society/ Australian College of Critical Care Nurses, and the American Thoracic Society for January 2006 to August 2012. PubMed was used for a citation search of relevant articles, and reference lists were examined.
Selection of Studies and Data Extraction
Two of the investigators (J.J. and L.R.) independently examined titles and abstracts to identify eligible studies. Full-text articles considered potentially relevant by either investigator were obtained and examined for eligibility. Disagreements were resolved through discussion with a third investigator (B.B.).
Two investigators (K.D. and L.R.) independently extracted study data by using a standardized form and then met to achieve consensus. Data included the country where the study was performed, methodological approach, methods of data collection and analysis, phenomena of interest, setting, sample inclusion and exclusion criteria, study findings (themes and subthemes), and conclusions. Extraction of these data were deemed necessary to address the research questions, confirm study eligibility, and provide a clear summary of each study. Data extractors were not blinded to study citations.
Collation of Findings
As recommended by Levac et al,9 3 steps were used to collate results. First, for analyzing the data, spreadsheets of descriptive characteristics were generated, including citation information; country; setting; participants; and themes, subthemes, and conclusions reported by the author or authors of each article. Studies were grouped according to type of respondent (patient, nurse, physician, health care provider) on the basis of presumed differences in the perspectives of each type of respondent. Thematic content analysis of themes and subthemes reported by the author or authors of included studies was done to identify common categories and themes within these categories. Second, for reporting results, tables were generated according to the thematic analysis to provide an overview of the breadth of and commonalities within the main themes or categories of included studies and to identify gaps in evidence. Third, for applying meaning to the results, recommendations for practice, policy, and future research were developed on the basis of the analyses.
A total of 8350 references were screened. After duplicates and obviously ineligible references were excluded, 117 full-text articles were retrieved, and 42 eligible studies were identified. An additional study was identified through reviews of conference abstracts (Figure 2).
Characteristics of Included Studies
Characteristics of included studies are shown in Table 1. The 2 studies,10,11 1 of which was a secondary analysis of the first, that reported experiences of patients’ family members also reported the perspectives of patients and health care providers on family presence. Only 1 study30 addressed weaning of children. A range of qualitative methods was used, including ethnographic or phenomenological approaches, case study, thematic content analysis, and a qualitative exploratory design similar to qualitative descriptive analysis53 ; however, most publications lacked detailed description of study methods. Several investigators claimed to use a grounded theory approach, although most used only constant comparative analysis techniques rather than full execution of this method (ie, theory generation).54
One of the goals was to understand decision-making processes and patient’s experiences.
The 2 most frequently described aims were understanding decision-making processes and the lived experience of patients during the weaning process from various perspectives. Other stated primary aims were to evaluate the impact of weaning protocols, technology in the weaning process, and organizational behavior related to successful implementation of weaning protocols.
Categories and Related Themes
Synthesized data from studies included in the review were grouped according to type of participant are presented in Tables 2 through 5. Column headings represent categories generated as a result of thematic analysis. Data described in cells are the themes and subthemes identified by the authors of the included studies.
Question 1: Factors Influencing the Weaning Process
For studies in which only nurses were included in the study sample, themes identified by the author or authors or the studies were grouped into 3 categories: nurses’ role or scope of practice, informing decision making, and influence on weaning outcome (Table 2). For nurses’ role and scope of practice, the themes identified were issues of credibility, accountability, and autonomy within a team and unwritten rules and boundaries that influence nurses’ role and scope of practice. Nurses’ role and scope of practice were explored from various perspectives, including the advantages and stressors of assuming a role in weaning management, the influence of technology, and weaning-related decision making. For the category informing decision making, 3 themes were identified: objective information, subjective information, and decision-making tools related to weaning. For the category influence on weaning outcome, 4 themes were identified: nurse-patient relationship, understanding the work of weaning, patients’ role in weaning, and role of the interprofessional team in weaning.
For studies that integrated perspectives from various health care providers, themes identified by the author or authors of the articles were grouped into 3 categories: role or scope related to weaning, factors that influence weaning decisions or use of protocols, and organizational structure or practice environment (Table 3). Lack or presence of understanding and respect for interprofessional roles and the respective impact of this lack or presence on weaning outcomes was the theme ascribed to role or scope related to weaning. For factors that influence weaning decisions or use of protocols, 3 themes were identified: knowledge, experience, or interpretation and the influence on competency and autonomy within the team; context of the decision; and the need to combine and/or balance subjective and objective information for decision making. Lack or presence of consistency, collaboration, communication, and organizational support and influence of the lack or presence on weaning outcomes was the theme identified for organizational structure or practice environment.
Themes identified by the author or authors of studies of physician respondents consisted of 2 categories: physicians’ perceptions of nurses’ role or scope of practice and tools or factors to facilitate weaning decisions (Table 4). Themes for physicians’ perceptions of nurses’ role or scope of practice were nurses’ competence, nurses’ experience, and interaction with nurses. Themes for tools or factors to facilitate weaning decisions included protocol- or tool-related issues, objective and subjective information, timing of weaning, and teamwork or team interaction.
Question 2: Perceptions of Weaning Strategies
Data from studies of nurse respondents specific to weaning protocols indicated that perceived usefulness of the protocols was influenced by nurses’ level of experience and type of patient and that protocols should be used in conjunction with experiential knowledge and understanding of patients’ experiences. Studies of health care providers that addressed implementation of weaning protocols indicated that protocols were perceived to provide a framework that increased nurses’ participation, promoted interprofessional communication, standardized the weaning process, and legitimized nurses’ role. Negative perceptions focused on inconsistent adherence, protocol rigidity and relevance, and apathy. In 2 studies,46,47 the investigators examined physicians’ perceptions specific to weaning protocols and found both favorable and unfavorable perceptions. Diversity of opinion was expressed about whether protocols served as a prompt or decreased physicians’ focus on weaning. Issues of rigidity and difficulty with application in a heterogeneous population of patients were raised.
Although studies that provided content analysis of open-ended questions within quantitative surveys were excluded from the thematic grid, similar issues were detected in terms of role and scope of practice, collaboration, the need for systematic processes as well as individualization, potential influences on weaning outcome, patient data used to inform decision making and factors influencing use of protocols.
Question 3: Patients’ and Patients’ Family Members’ Experience of Weaning
Themes identified by the author or authors of studies of patients’ experience were grouped into 4 categories: experience of mechanical ventilation and weaning, experience of the ICU environment, psychological phenomena, and enablers of weaning success (Table 5). Themes for experience of mechanical ventilation and weaning were physical discomfort, impaired communication, and patient work. Negative aspects of both the physical environment and staff interaction were themes under the category experience of the ICU environment. Themes for psychological phenomena were fear, lack of control, realization of death, and concepts of self (ie, the effect on a patient’s sense of identity). Themes for enablers of weaning success included the role of health care providers, patients’ family members, self (ie, the patient), and faith. For the 2 studies (1 primary49 and 1 secondary50 analysis of the first study) that included members of a patient’s family, 1 category was detected: duality of the positive and negative influence of family presence and surveillance on weaning success and anxiety management.
Most reviews of weaning from mechanical ventilation have examined only quantitative data describing efficacy of spontaneous breathing trials, weaning modes, and care based on protocols2,55 to identify clinical strategies that enable successful weaning. Our objective was to assess the range of qualitative literature that includes contextual issues, clinicians’ perceptions of tools to promote timely weaning, and psychosocial aspects such as the experiences of patients and patients’ family members. We found several studies (n = 43); however, research objectives and perspectives were disparate. We identified only 1 study of weaning in children, so our findings primarily relate to weaning of adult ICU patients. Studies were divided between those that identified factors important to individualized care and experience and those that investigated methods of standardizing care, such as objective parameters for decision making or use of weaning protocols and guidelines. This characteristic made interpretive synthesis difficult, and thus we opted to generate a narrative summary to comprehensively map knowledge provided by the included studies.
We found several key themes across studies. The critical role of subjective knowledge, (knowing the patient) in association with objective clinical data was reported in several studies, highlighting the need to individualize the weaning process. Ethnographic studies indicated that weaning decision making is a social interactive process between health care providers and patients that involves assimilation of objective and subjective data influenced by context. Although the importance of this subjective knowledge and social interaction, primarily acknowledged by nurses, may affect the outcome of weaning, quantifying or determining the impact is difficult. As a result, subjective knowledge is devalued in decisions about weaning interventions, which are more commonly based solely on objective criteria.
Another key theme was the influence of interprofessional collaboration, professional boundaries, roles, practice scope, and teamwork on weaning success. International variation exists in ICU organizations and philosophies of interprofessional collaboration. For example, differences exist in nurse and physician staffing models, specialty education for nurses, decision-making hierarchy, and assignment of roles and responsibilities for weaning.56,57 Perceptions of nurses’ experience and competence were key themes related to physicians’ perspectives of nurses’ role, the impact of the perceptions on weaning success, and the usefulness of weaning protocols. Physicians often defined or limited nurses’ scope of practice in relation to weaning on the basis of these perceptions rather than using interprofessional collaborative discussion to define this.
Most studies with a focus on patients were appropriately phenomenological, and the focus was lived experience of being weaned from mechanical ventilation. These studies elucidated the extreme physical and psychological challenges of weaning and underscored how horrible the experience can be for patients, regardless of how well weaning proceeds clinically. As well, a description of the roles of patients’ family members and health care providers from the patients’ perspectives provides insight into the influence of clinicians’ behaviors and organizational structure on the weaning process. These data provide a strong reminder to clinicians and researchers that understanding and considering the experiences of patients and patients’ family members are crucial to development of interventions aimed at weaning success.
Studies that included health care providers were more diverse than studies that included patients and patients’ family members. Studies that included physicians were clinically oriented and primarily sought opinions on procedures and decision making for weaning readiness. Studies that included interviews of nurses and other health care providers focused on experiential understanding of the weaning process. This focus may reflect differences in underlying care philosophies or role expectations of the various professions but also indicates the need for investigations with reverse aims, for example, how physicians experience the weaning process or interact with patients undergoing weaning.
Recommendations for Practice, Policy, and Future Research
We have several recommendations. Interprofessional collaboration, team communication that includes patients and patients’ family members, and care continuity should be prioritized to promote successful weaning. Systematic approaches that enable timely assessment of readiness for weaning and extubation and of the progression of weaning should be adaptable to individual needs and responses of patients. Clinicians and policy makers should consider the physical and psychological effect of prolonged weaning and promote patient- and family-centered strategies that incorporate collaborative goal setting and consider the role of therapeutic family presence. The usefulness of strategies such as weaning protocols should be evaluated in light of the existing organizational structure and clinical environment before widespread adoption is mandated.
A scoping review provides a map not only of existing literature but also of gaps in knowledge. We detected a need for improved understanding from physicians’ perspective because studies identified tensions associated with roles and scope of practice that may adversely influence weaning. Because weaning is a complex intervention influenced by various factors, well-designed qualitative studies to explore organizational factors such as interprofessional collaboration conducted alongside studies to examine effectiveness or implementation of strategies to optimize weaning are needed to evaluate the process of delivery and the effect on success.
Strengths, Weaknesses, and Challenges
On the basis of our review, we mapped existing qualitative literature, providing enhanced understanding of weaning from the perspectives of multiple key stakeholders and direction for clinical care, policy, and research. Strengths of our review are the application of highly systematic search methods, including an extensive search of gray literature with no language exclusions, and data extraction and mapping according to established methods for scoping reviews8,9 with input from authors with method and content expertise.
As in any review, we may have missed a small percentage of relevant studies. However, because of our extensive search strategy guided by librarian expertise, we think it unlikely that we missed important data. Scoping reviews differ from other types of systematic reviews in that they are designed to map existing literature without quality assessment or extensive data synthesis. To this end, we chose to synthesize only major themes of included studies to enable data presentation rather than impose our own analysis. This synthesis might have misrepresented or oversimplified the original interpretation of the data. Metasynthesis of qualitative data pertaining to each of our 3 research questions will further extend our understanding of current evidence. As an extension of this scoping review, we are now completing a metasynthesis of studies specific to weaning protocols.58
This review highlights various subjective and contextual influences that influence the weaning process. Consistent themes included the importance of interprofessional collaboration and communication, need for subjective knowledge of the patient involved combined with objective clinical data, need to balance systematic processes that reduce weaning delays with the individual needs of patients and patients’ family members, and appreciation of the physical and psychological work of patients. Although these themes may be considered predictable and well recognized, often they are ignored in the design and evaluation of strategies to improve weaning outcomes. Gaps in knowledge included better understanding of physicians’ perspectives and the influence of interprofessional relationships and ICU context on weaning outcomes and the experiences of patients and patients’ families.
This study was conducted at the Lawrence S. Bloomberg Faculty of Nursing, University of Toronto.
This research was supported by a research grant from the Ontario Respiratory Care Society.
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