Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

A decadal synthesis of atmospheric emissions, ambient air quality, and deposition in the oil sands region

This review is part of a series synthesizing peer-reviewed literature from the past decade on environmental monitoring in the oil sands region (OSR) of northeastern Alberta. It focuses on atmospheric emissions, air quality, and deposition in and downwind of the OSR. Most published monitoring and research activities were concentrated in the surface-mineable region in the Athabasca OSR. Substantial progress has been made in understanding oil sands (OS)-related emission sources using multiple approaches: airborne measurements, satellite measurements, source emission testing, deterministic modeling, and source apportionment modeling. These approaches generally yield consistent results, indicating OS-related sources are regional contributors to nearly all air pollutants. Most pollutants exhibit enhanced air concentrations within ~20 km of surface-mining activities, with some enhanced >100 km downwind. Some pollutants (e.g., sulfur dioxide, nitrogen oxides) undergo transformations as they are transported through the atmosphere. Deposition rates of OS-related substances primarily emitted as fugitive dust are enhanced within ~30 km of surface-mining activities, whereas gaseous and fine particulate emissions have a more diffuse deposition enhancement pattern extending hundreds of kilometers downwind. In general, air quality guidelines are not exceeded, although these single-pollutant thresholds are not comprehensive indicators of air quality. Odor events have occurred in communities near OS industrial activities, although it can be difficult to attribute events to specific pollutants or sources. Nitrogen, sulfur, polycyclic aromatic compounds (PACs), and base cations from OS sources occur in the environment, but explicit and deleterious responses of organisms to these pollutants are not as apparent across all study environments; details of biological monitoring are discussed further in other papers in this special series. However, modeling of critical load exceedances suggests that, at continued emission levels, ecological change may occur in future. Knowledge gaps and recommendations for future work to address these gaps are also presented. Integr Environ Assess Manag 2022;18:333-360. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

History, overview, and governance of environmental monitoring in the oil sands region of Alberta, Canada

Over the past decades, concerns regarding the local and cumulative impacts of oil sands development have been increasing. These concerns reflect the industry's emissions, land disturbance, water use, and the resulting impacts to Indigenous Rights. Effective environmental management is essential to address and ultimately manage these concerns. A series of ambient regional monitoring programs in the oil sands region (OSR) have struggled with scope and governance. In the last 10 years, monitoring has evolved from a regulatory-driven exercise implemented by industry into a focused, collaborative, multistakeholder program that attempts to integrate rigorous science from a multitude of disciplines and ways of knowing. Monitoring in the region continues to grapple with leadership, governance, data management, scope, and effective analysis and reporting. This special series, "A Decade of Research and Monitoring in the Oil Sands Region of Alberta, Canada," provides a series of critical reviews that synthesize 10 years of published monitoring results to identify patterns of consistent ecological responses or effects, significant gaps in knowledge, and recommendations for improved monitoring, assessment, and management of the region. The special series considered over 300 peer-reviewed papers and represents the first integrated critical review of the published literature from the region. This introductory paper of the series introduces the history of ambient environmental monitoring in the OSR and discusses historic and ongoing challenges with the environmental monitoring effort. While significant progress has been made in areas of governance, expanded geographical scope, and inclusion of Indigenous communities in monitoring in the region, significant issues remain regarding a lack of integrated reporting on environmental conditions, public access to data, and continuity of monitoring efforts over time. Integr Environ Assess Manag 2022;18:319-332. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Essential components and pathways for developing Indigenous community-based monitoring: Examples from the Canadian oil sands region

Historically, environmental research and monitoring in the Alberta oil sands region (OSR) located in northeastern Alberta, Canada, have largely neglected, meaningful Indigenous participation. Through years of experience on the land, Indigenous knowledge (IK) holders recognize change on the landscape, drawing on inextricable links between environmental health and practicing traditional rights. The cumulative impacts of crude oil production are of great concern to Indigenous communities, and monitoring initiatives in the OSR provide unique opportunities to develop Indigenous community-based monitoring (ICBM). A review of ICBM literature on the OSR from 2009 to 2020 was completed. Based on this review, we identify best practices in ICBM and propose governance structures and a framework to support meaningful integration of ICBM into regulatory environmental monitoring. Because it involves multimedia monitoring and produces data and insights that integrate many aspects of the environment, ICBM is important for natural science research. ICBM can enhance the relevance of environmental monitoring by examining relationships between physical and chemical stressors and culturally relevant indicators, so improving predictions of long-term changes in the environment. Unfortunately, many Indigenous communities distrust researchers owing to previous experiences of exploitive use of IK. In the present paper, we recommend important practices for the integration of IK into regional environmental monitoring programs. ICBM is important to communities because it includes conditions to which communities can exercise traditional rights, and highlight how industrial activities affect this ability. Equally important, ICBM can generate a resurgence of Indigenous languages and subsequently traditional practices; it can also revive the connection with traditional lands and improve food security. Integr Environ Assess Manag 2022;18:407-427. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

A synthetic review of terrestrial biological research from the Alberta oil sands region: 10 years of published literature

In the past decade, a large volume of peer-reviewed papers has examined the potential impacts of oil and gas resource extraction in the Canadian oil sands (OS). A large proportion focuses on terrestrial biology: wildlife, birds, and vegetation. We provide a qualitative synthesis of the condition of the environment in the oil sands region (OSR) from 2009 to 2020 to identify gaps and progress cumulative effects assessments. Our objectives were to (1) qualitatively synthesize and critically review knowledge from the OSR; (2) identify consistent trends and generalizable conclusions; and (3) pinpoint gaps in need of greater monitoring or research effort. We visualize knowledge and terrestrial monitoring foci by allocating papers to a conceptual model for the OS. Despite a recent increase in publications, focus has remained concentrated on a few key stressors, especially landscape disturbance, and a few taxa of interest. Stressor and response monitoring is well represented, but direct monitoring of pathways (linkages between stressors and responses) is limited. Important knowledge gaps include understanding effects at multiple spatial scales, mammal health effects monitoring, focused monitoring of local resources important to Indigenous communities, and geospatial coverage and availability, including higher attribute resolution in human footprint, comprehensive land cover mapping, and up-to-date LiDAR coverage. Causal attribution based on spatial proximity to operations or spatial orientation of monitoring in the region is common but may be limited in the strength of inference that it provides. Integr Environ Assess Manag 2022;18:388-406. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

An integrated knowledge synthesis of regional ambient monitoring in Canada's oil sands

The desire to document and understand the cumulative implications of oil sands (OS) development in the ambient environment of northeastern Alberta has motivated increased investment and release of information in the past decade. Here, we summarize the knowledge presented in the theme-based review papers in this special series, including air, surface water, terrestrial biology, and Indigenous community-based monitoring in order to (1) consolidate knowledge gained to date, (2) highlight key commonalities and gaps, and (3) leverage this knowledge to assess the state of integration in environmental monitoring efforts in the OS region and suggest next steps. Among air, water, and land studies, the individual reviews identified a clear focus on describing stressors, including primarily (1) contaminant emission, transport, transformation, deposition, and exposure, and (2) landscape disturbance. These emphases are generally partitioned by theme; air and water studies focus heavily on chemical stressors, whereas terrestrial monitoring focuses on biological change and landscape disturbance. Causal attribution is often stated as a high priority objective across all themes. However, studies often rely on spatial proximity to attribute cause to industrial activity, leaving causal attribution potentially confounded by spatial covariance of both OS- and non-OS-related stressors in the region, and by the complexity of interacting pathways between sources of environmental change and ecological receptors. Geospatial and modeling approaches are common across themes and may represent clear integration opportunities, particularly to help inform investigation-of-cause, but are not a replacement for robust field monitoring designs. Cumulative effects assessment remains a common focus of regional monitoring, but is limited in the peer-reviewed literature, potentially reflecting a lack of integration among monitoring efforts beyond narrow integrated interpretations of results. Addressing this requires greater emphasis on a priori integrated data collection and integrated analyses focused on the main residual exposure pathways, such as atmospheric deposition. Integr Environ Assess Manag 2022;18:428-441. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Comparing tiltmeters for crustal deformation measurement--a preliminary report

A collection of high-precision tiltmeters is being operated at Pinon Flat Observatory, southern California, both to compare instruments and to measure tectonic deformation. We report on 1.2 years of data from four of these: two Michelson-Gale long fluid tiltmeters, one long center-pressure tiltmeter, and a shallow borehole tiltmeter. The three long-base instruments are all located on the same baseline, with a precise leveling line running between their end-monuments. At nontidal frequencies, only the two Michelson-Gale instruments show some coherence (gamma 2 = .3 for periods of 2 to 4 days), while the center-pressure instrument is correlated with air temperature at periods from a few days to a few weeks. The most stable tilt record shows a secular rate of 0.28 mu rad/a, which may be real. Over much longer times, leveling to specially stabilized bench-marks should confirm this. Comparing instruments has identified more and less successful measurement techniques; it appears that low-noise data will most probably be produced only by relatively complex and expensive instruments, though even for these, the operating costs over any reasonable lifetime will exceed the capital cost. Even the best existing sensors must be improved to measure continuous tectonic motions.