Review Article

Evidence-based clinical pathway development for airway pressure release ventilation in adult acute respiratory distress syndrome: Findings from a rapid literature review

Johanna Albertse, Isabel Coetzee-Prinsloo, Irene Lubbe

Received: 03 Nov. 2025; Accepted: 29 June 2026; Published: 17 Aug. 2026

Copyright: © 2026. The Authors. Licensee: AOSIS.
This work is licensed under the Creative Commons Attribution 4.0 International (CC BY 4.0) license (https://creativecommons.org/licenses/by/4.0/).

Abstract

Clinical pathways (CPs) are structured, multidisciplinary plans that translate evidence into practice to improve care quality and consistency. Airway pressure release ventilation (APRV) is an advanced ventilator mode with potential benefits for adults with acute respiratory distress syndrome (ARDS), yet its implementation lacks standardised protocols. In South African critical care settings, nurses often adjust ventilators and respond to clinical changes without respiratory therapists or immediate physician oversight, highlighting the need for structured, evidence-informed support. To synthesise evidence on APRV ventilator settings, protocols and implementation considerations to inform the development of an evidence-based clinical pathway for APRV therapy to treat adults with ARDS. A rapid literature review of peer-reviewed studies published from January 2016 to July 2022 was conducted. Searches were performed in PubMed, EBSCOhost Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Google Scholar. Twenty-one studies meeting eligibility criteria were analysed using descriptive thematic synthesis, focusing on APRV protocols, ventilator parameters, sedation strategies and alarm guidance. No universally accepted APRV protocol was identified. Implementation is largely guided by institution-specific protocols and physician preference. Sedation management is recognised as essential, but detailed recommendations are limited. Information on alarm limits and safety parameters within the mode is minimal. These findings emphasise the variability and uncertainty in APRV practice and the importance of context-specific, evidence-informed CPs.

Contribution: Clear pathways can standardise care, improve patient safety and strengthen multidisciplinary collaboration in critical care settings.

Keywords: acute respiratory distress syndrome; airway pressure release ventilation; clinical pathways; critical care nursing; mechanical ventilation; rapid literature review.

Introduction

Background

Clinical pathways (CPs) are multidisciplinary, structured plans of care designed to translate the best available evidence into routine clinical practice for defined patient populations and clinical problems. In critical care settings, CPs support complex, multidisciplinary clinical decision-making by standardising key interventions, reducing unwarranted variation in practice and promoting consistent, evidence-based care while allowing adaptation to local healthcare contexts. As evidence-informed tools, CPs depend on the systematic identification, appraisal and synthesis of relevant research to ensure methodological rigour, clinical relevance and contextual applicability (Albertse et al., 2023; Aspland et al., 2021; Herawati et al., 2022; Trimarchi et al., 2021).

The development of CPs is particularly important in the management of complex and high-risk conditions such as acute respiratory distress syndrome (ARDS), where care is resource intensive, and outcomes are influenced by timely, coordinated and evidence-based interventions. Acute respiratory distress syndrome is defined according to the Berlin criteria, which provide standardised diagnostic parameters based on timing of onset, chest imaging findings, severity of hypoxaemia and the origin of pulmonary oedema (Matthay et al., 2019; Papazian et al., 2019; Smith & Richards, 2021). The use of standardised diagnostic criteria ensures consistency in identifying the target population and strengthens the alignment between evidence synthesis and clinical application.

Airway pressure release ventilation (APRV) has been used for more than three decades as a mode of invasive mechanical ventilation and is associated with potential physiological and clinical benefits for patients with ARDS. Despite increasing interest in APRV therapy, there remains limited consensus and insufficient practical guidance regarding ventilator settings, initiation, titration and weaning strategies for its use in adult patients with ARDS (Andrews et al., 2022; Chen et al., 2021; Fredericks et al., 2020; Smith & Richards, 2021). This lack of standardised guidance contributes to variability in clinical practice and uncertainty among critical care clinicians, particularly nurses, highlighting the need for a structured, evidence-based clinical pathway to support the safe and consistent implementation of APRV therapy in this population (Andrews et al., 2022).

The development of an evidence-based clinical pathway requires a robust synthesis of available research. Systematic literature reviews are widely regarded as the gold standard for evidence synthesis because of their comprehensive search strategies, transparent methodologies and rigorous appraisal processes (Kabir et al., 2023; Toronto & Remington, 2020). However, traditional systematic reviews are often time consuming and resource intensive, which may limit their feasibility when timely evidence is required to inform clinical practice.

Rapid literature reviews (RLRs) offer a pragmatic alternative by retaining core principles of systematic review methodology – such as structured search processes, explicit eligibility criteria and transparent reporting – while allowing greater methodological flexibility. This flexibility commonly includes narrower research questions, focused search strategies and shorter timelines, enabling timely synthesis of evidence that is directly applicable to clinical decision-making (Devane et al., 2024; Garritty et al., 2021; Kabir et al., 2023; Snyder, 2019). Rapid reviews are increasingly used to inform healthcare interventions, including guideline development and clinical pathway design (Wilson et al., 2021).

The purpose of this study was therefore to conduct a semi-systematic RLR to synthesise evidence on ventilator settings, protocols and clinical guidance to inform the development of an evidence-based clinical pathway for APRV therapy in adult patients with ARDS. The review question guiding this study was: What evidence is available regarding ventilator settings, clinical protocols and implementation considerations for the use of APRV in adult patients with ARDS?

Methods

This study employed a semi-systematic RLR methodology to synthesise evidence relevant to informing the development of a clinical pathway for APRV in adult patients with ARDS. Rapid reviews are appropriate for focused, practice-oriented questions that require timely evidence synthesis while retaining transparency and methodological rigour (Garritty et al., 2021, 2024; Snyder, 2019). The review was guided by the stepwise framework for semi-systematic reviews described by Snyder (2019), alongside methodological guidance from the Cochrane Rapid Reviews Methods Group (Garritty et al., 2021).

To ensure that the evidence synthesis addressed a clearly defined and clinically relevant question, the review population was specified as adult patients diagnosed with ARDS according to the Berlin criteria (Matthay et al., 2019; Smith & Richards, 2021). The review question was framed using the Population, Phenomenon of Interest, and Context (PICo) qualitative framework. This framework guided the systematic identification and selection of literature relevant to the use of APRV therapy in adult critical care patients with ARDS (Covvey et al., 2024; Hosseini et al., 2024).

Consistent with rapid review methodology, pragmatic methodological adaptations were applied, including restriction of databases searched, a defined publication timeframe and omission of a formal critical appraisal of included studies. These adaptations were implemented to enhance feasibility while preserving systematic processes for literature searching, study selection and data synthesis (Garritty et al., 2021).

Review design

A semi-systematic RLR design was selected because of the narrow, practice-oriented focus of the review question and the need for timely synthesis to inform clinical pathway development. Airway pressure release ventilation represents an evolving mode of invasive mechanical ventilation, with increasing clinical interest following its expanded use during the COVID-19 pandemic (Alqahtani et al., 2020; Mahmoud et al., 2021; Rola & Daxon, 2022; Smith & Richards, 2021; Zorbas et al., 2021). The emerging nature of the evidence base and the absence of standardised clinical protocols further supported the selection of a rapid review approach to efficiently identify and synthesise relevant contemporary literature (Andrews et al., 2022; Mahmoud et al., 2021; Navas-Blanco & Dudaryk, 2020; Smith & Richards, 2021).

The review followed a structured, stepwise process comprising formulation of the review question, planning of the review, systematic searching, study selection, data extraction, thematic synthesis and presentation of findings using a synthesis matrix. Figure 1 illustrates the steps undertaken, adapted from Snyder (2019).

FIGURE 1: Steps and actions of the rapid literature review process.

Review question

The review question was structured using the PICo framework, which identifies the Population, Phenomenon of Interest and Context relevant to the study (Covvey et al., 2024; Hosseini et al., 2024). The PICo elements directly informed the search strategy, study selection and eligibility criteria, as summarised in Table 1. The review question asked: What evidence is available regarding ventilator settings, clinical protocols and implementation considerations for the use of APRV in adult patients with ARDS?

Justification of PICo elements and eligibility criteria

Population

The review population was limited to adults (≥18 years) because of physiological differences in mechanical ventilation management between adult and paediatric patients, as well as distinct approaches to ventilation in paediatric critical care. The commissioning panel for the clinical pathway development specified an adult patient population.

Phenomenon of interest

Airway pressure release ventilation therapy was selected as an advanced mode of invasive mechanical ventilation with ventilator settings and implementation considerations that differ substantially from conventional volume- and pressure-controlled modes. This focus enabled targeted synthesis of evidence related to ventilator settings, protocols and clinical guidance specific to APRV therapy (Albertse et al., 2023; Andrews et al., 2022; Smith & Richards, 2021).

Context

Critical care settings were selected to ensure alignment between the review findings and the clinical environment in which the proposed clinical pathway would be implemented.

Acute respiratory distress syndrome definition

The Berlin criteria were applied to define ARDS to ensure consistency in identifying the target population across included studies (Matthay et al., 2019; Papazian et al., 2019; Smith & Richards, 2021).

Time frame

Publications from January 2016 to July 2022 were included. The lower limit was informed by the first randomised controlled trial evaluating APRV therapy in patients diagnosed and treated for ARDS (Zhou et al., 2017), representing an important development in the evidence base. The upper limit of July 2022 was determined to allow synthesis of findings in time to inform the next step of the clinical pathway development process by September 2022.

Publication type

Only peer-reviewed articles published in accredited journals were included. Grey literature and non-academic sources were excluded to ensure scientific credibility.

The review question was further assessed using the FINER criteria – feasibility, interest, novelty, ethics and relevance – to confirm its suitability (Covvey et al., 2024; Hosseini et al., 2024). The assessment process is illustrated in Figure 2.

FIGURE 2: Assessment of the review question against the feasibility, interest, novelty, ethics and relevance criteria.

Based on the review question, the following eligibility criteria were defined.

Inclusion criteria

• Publications between January 2016 and July 2022
• English-language publications
• Peer-reviewed articles published in accredited journals
• Studies involving adult patients (≥ 18 years)
• Studies involving patients with ARDS as defined by the Berlin criteria
• Studies addressing the implementation and use of the APRV mode of ventilation and/or APRV therapy

Exclusion criteria

• Grey literature and non-academic sources
• Editorials, commentaries and letters to the editor
• Studies focusing on non-invasive ventilation strategies
• Animal studies

Sources of evidence and review process

A structured electronic search was conducted in PubMed, EBSCOhost (including CINAHL) and Google Scholar between May 2022 and July 2022. These databases were selected to ensure comprehensive coverage of medical, nursing and critical care literature.

Searches combined controlled vocabulary and free-text terms related to ARDS and APRV, including ‘acute respiratory distress syndrome’, ‘ARDS’, ‘airway pressure release ventilation’ and ‘APRV’, using Boolean operators. Searches were restricted to English-language publications and the predefined publication period.

Given the intended application of findings to South African critical care settings, an initial focused search for South African literature was conducted. Only one eligible South African publication was identified (Smith & Richards, 2021). Backward and forward citation tracking of this article was therefore performed to identify additional relevant international studies.

All retrieved articles were screened against the inclusion and exclusion criteria. Articles meeting eligibility criteria were included in the synthesis of evidence, focusing on ventilator settings, clinical protocols and implementation considerations for APRV in adult ARDS patients.

Study selection and screening

All identified records were collated, and duplicates were removed. Titles and abstracts were screened independently by two reviewers against the predefined eligibility criteria. Full-text articles of potentially eligible studies were retrieved and independently assessed. Discrepancies were resolved through discussion until consensus was achieved.

Studies examining APRV use in patients at risk of ARDS without a confirmed diagnosis (according to the Berlin criteria) were excluded to maintain population homogeneity. Backward and forward citation tracking of included studies was conducted using the same screening criteria. The study selection process is illustrated in the preferred reporting items for systematic reviews and meta-analyses (PRISMA) flow diagram (Figure 3).

FIGURE 3: Preferred reporting items for systematic reviews and meta-analyses flow diagram of the literature search and study selection process.

The search was limited to peer-reviewed publications from January 2016 to July 2022. This timeframe follows the publication of the first randomised controlled trial evaluating APRV for ARDS (Zhou et al., 2017) and aligns with the timeline required to inform clinical pathway development by September 2022.

Data analyses and synthesis

Data analysis followed a descriptive thematic synthesis approach, suitable for rapid reviews aiming to summarise and compare findings across heterogeneous study designs (Creswell & Creswell, 2023; Snyder, 2019). Following study selection, key data were extracted from each included article into a synthesis matrix, capturing study characteristics, APRV protocols, ventilator settings (including P_high, T_high, P_low and T_low) and adjunctive practices (e.g. sedation, FiO₂ titration, automatic tube compensation) (Albertse et al., 2023; Kabir et al., 2023).

Data coding was conducted manually. Extracted information was initially organised according to predefined clinical categories relevant to APRV use. Patterns and similarities across studies were then identified, and an inductive approach was applied to group related findings into overarching themes. This process resulted in the identification of three main themes, which are presented descriptively to highlight areas of convergence and variation across the literature rather than to generate theory.

The synthesis matrix enabled a systematic comparison of study findings and supported transparent presentation of results. Study characteristics are presented first in the Results section, followed by a thematic synthesis of findings related to APRV protocols, ventilator settings and safety considerations. A thematic map illustrating the three main themes identified from the data is presented in Figure 4.

FIGURE 4: Thematic map showing the three main themes identified from the included studies.

Review findings

Study’s characteristics

The final sample comprised 21 peer-reviewed articles published between 2016 and 2022. Most studies originated from North America, with additional publications from Asia, the Middle East, Australia and one South African study (Smith & Richards, 2021).

The included studies represented a range of research designs:

• 11 review articles, including three systematic reviews with meta-analyses
• Two retrospective analyses and one prospective observational study
• Three randomised controlled trials (RCTs)
• One survey
• One educational article
• One case study

Across the included literature, study aims and reporting focused on various aspects of APRV use in adult patients with ARDS, including ventilator settings, clinical protocols and adjunctive management strategies. Table 2 provides a descriptive summary of study characteristics, including year of publication, country of origin, study design, reported protocols and APRV ventilator settings.

Thematic findings

The included studies, summarised in Table 2, report substantial variation in the use of APRV, including differences in ventilator settings and adjunctive management practices across institutions. The findings are synthesised under three key areas: Protocols and guidelines, ventilator settings and alarm limits in adult patients treated with APRV for ARDS.

Protocols and guidelines

Across the included studies, no universally accepted or published protocol for APRV initiation, maintenance or weaning was identified. Most studies described institution-specific approaches to APRV application. Where protocols were referenced, practices were commonly informed by the time-controlled adaptive ventilation (TCAV) protocol (Habashi et al., 2021), the Zhou early-application protocol (Zhou et al., 2017) or variations combining elements of both approaches.

Sedation protocols and management were frequently discussed in relation to APRV use (Albert et al., 2020; Smith & Richards, 2021; Zhou et al., 2017). Several studies reported the use of sedation assessment tools, such as the Richmond Agitation-Sedation Scale (RASS), to guide sedative and analgesic titration. Zhou et al. (2017) described the titration of both ventilator settings and sedation during early APRV application, and the case study by Albert et al. (2020) emphasises the importance of planned sedation management during the weaning phase of APRV therapy.

Ventilator settings

Standard APRV parameters reported across studies included lung inflation pressure (P_high), lung inflation time (T_high), lung deflation pressure (P_low) and lung deflation time (T_low). The included literature described a range of approaches to setting and adjusting these parameters (Andrews et al., 2022; Fredericks et al., 2020; Joseph et al., 2021; Rola & Daxon, 2022; Smith & Richards, 2021). Swindin et al. (2020) provided practical guidance for clinicians less familiar with APRV, while the case study by Albert et al. (2020) described APRV settings according to stages within the ARDS disease continuum.

Several studies addressed titration of inspired oxygen fraction (FiO₂) in response to oxygenation status, particularly during weaning (Joseph et al., 2021; Li et al., 2016; Swindin et al., 2020; Zhou et al., 2017). Two studies reported on the activation and deactivation of automatic tube compensation (ATC) during APRV therapy (Albert et al., 2020; Swindin et al. 2020).

Alarm limits

Only one study explicitly reported on the configuration of alarm limits during APRV therapy (Albert et al., 2020), indicating limited published guidance in this area.

A summary of findings

Overall, the review revealed substantial variability in APRV application, ventilator settings and supporting protocols across studies and institutions. No universal guideline exists, and practice is largely guided by institution-specific protocols and physician preference, including the TCAV and Zhou early-application methods. Sedation management, FiO₂ titration and ATC activation are important adjuncts, but detailed guidance – particularly regarding alarm limits and safety parameters – is limited. These findings underscore the emerging role of APRV therapy in adult critical care and highlight the need for context-specific CPs to support safe and standardised implementation, especially in under-researched regions such as South Africa.

Discussion

This RLR highlights considerable variability in the application of APRV therapy for adult patients with ARDS, with no universally accepted protocol for initiation, maintenance or weaning. Most studies referenced either the TCAV protocol (Habashi et al., 2021) or the Zhou early-application protocol (Zhou et al., 2017), indicating that APRV practice is largely institution specific and adapted to local expertise and resources.

Sedation management emerged as a critical adjunct to successful APRV therapy. Several studies emphasised careful titration of sedatives and analgesics to maintain patient–ventilator synchrony and optimise clinical outcomes. Additional strategies, including titration of FiO₂ and the activation or deactivation of ATC, were reported as methods to individualise care, particularly during the weaning phase. Alarm settings during APRV therapy were addressed insufficiently in the literature, highlighting a notable gap in published safety guidance.

These findings are particularly relevant in the South African critical care context, where nurses are often primarily responsible for ventilator management. In the absence of respiratory therapists and with limited immediate physician availability, nurses must make timely ventilator adjustments and respond rapidly to patient deterioration. This clinical reality underscores the importance of structured, evidence-informed CPs to support safe and consistent decision-making when using APRV therapy. Well-designed CPs can reduce practice variability, enhance multidisciplinary collaboration and support coordinated, evidence-based patient care.

Strengths of the study

This review has several strengths. The research question was focused, feasible and directly aligned with the practical objective of informing clinical pathway development. The structured RLR methodology enabled timely synthesis of available evidence while maintaining transparency and methodological rigour. Visual tools, including the synthesis matrix and thematic map, facilitated systematic comparison of findings and enhanced their clinical applicability. Inclusion of international literature alongside one South African study (Smith & Richards, 2021), supplemented by citation tracking, further strengthened contextual relevance.

Limitations of the study

Several limitations should be acknowledged. The number of included studies was relatively small, reflecting both the emerging nature of APRV therapy and the restrictive inclusion criteria. Considerable heterogeneity across study designs, protocols and ventilator settings limits generalisability. Exclusion of grey literature may have resulted in omission of additional context-specific guidance. In addition, a formal methodological quality appraisal was not conducted, which may affect the certainty of the synthesised evidence.

Conclusion

Airway pressure release ventilation offers potential benefits for adult patients with ARDS; however, current evidence remains variable and largely institution specific. This variability reinforces the need for structured, evidence-informed CPs, particularly in the South African private health critical care units where nurses must frequently make rapid clinical decisions in the absence of respiratory therapists or immediate physician support. Developing clear CPs can standardise APRV practice, improve patient safety and strengthen multidisciplinary collaboration. Future research should prioritise robust empirical studies and consensus-based guideline development to address existing evidence gaps and support the safe and effective implementation of APRV therapy for treating adult patients with ARDS.

Acknowledgements

This article is based on research originally conducted as part of Johanna Albertse’s master’s thesis titled ‘Developing a clinical pathway for using the airway pressure release ventilation mode to mechanically ventilate adult patients presenting with acute respiratory distress syndrome’, submitted to the University of Pretoria 2023. The thesis is currently unpublished and not publicly available. The thesis was supervised by Isabel Coetzee-Prinsloo and Irene Lubbe. The thesis was reworked, revised and adapted into a journal article for publication. The authors confirm that the content has not been previously published or disseminated and complies with ethical standards for original publication.

The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article.

Johanna Albertse: Conceptualisation, Data curation, Investigation, Methodology, Writing – original draft, Writing – review & editing. Isabel Coetzee-Prinsloo: Data curation, Methodology, Supervision, Writing – review & editing. Irene Lubbe: Conceptualisation, Data curation, Methodology, Supervision, Writing – original draft, Writing – review & editing. All authors reviewed the article, contributed to the discussion of results, approved the final version for submission and publication and take responsibility for the integrity of its findings.

The study was approved by the research and ethics committees of the University of Pretoria; ethics reference number 119/2022 and Mediclinic Southern Africa (reference number 20220523). The study adhered to the principles of the Declaration of Helsinki and the directives published by the South African National Health Research Ethics Council.

The authors received no financial support for the research, authorship and/or publication of this article.

The data that support the findings of this study are not openly available and are available from the corresponding author, Johanna Albertse, upon reasonable request.

The views and opinions expressed in this article are those of the authors and are the product of professional research. They do not necessarily reflect the official policy or position of any affiliated institution, funder, agency or that of the publisher. The authors are responsible for this article’s results, findings and content.

References