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.

Do oropharyngeal throat packs prevent fluid ingestion during orthognathic surgery?

The oropharyngeal throat pack is commonly used in oral and maxillofacial surgery despite debated evidence regarding its barrier function. The study objectives were to investigate whether the oropharyngeal pack reduces blood ingestion and to evaluate its relationship with postoperative nausea and vomiting (PONV) and throat pain. This was a single-center, parallel group, single-blind randomized controlled trial. Participants undergoing orthognathic surgery, age ≥16 years, were included in the study. After intubation and prior to surgery start, the treatment group received oropharyngeal packing; the control group received no packing. Outcome variables were the quality of gastric contents aspirated by nasogastric tube (bloody or not bloody), PONV, and throat pain (visual analog scale). Thirty patients (treatment n = 15; control n = 15) were randomized and analyzed. There was no difference between the groups in quality of gastric contents (P = 1.00) or incidence of PONV at 2 hours and 24 hours (P = 1.00). Throat pain incidence and severity at 2 hours were both higher in the treatment group, but this was not statistically significant (P = 0.128, P = 0.223). The results indicate that the oropharyngeal pack is not an effective barrier against blood ingestion. Oropharyngeal packs do not improve or worsen PONV, but may increase throat pain.

Asset-based approaches to promote health in place-based communities: when the context matters

Background

In recent years, asset-based approaches (ABAs) to promote health have increasingly been adopted as a strategy to reduce health inequalities between neighbourhoods. However, evidence of impact is still limited due to their complexity. This research aimed to explore what changes ABAs generate, studying two asset-based initiatives that train local lay people to become peer health promoters, implemented in two different settings (Spain and UK).

Methods

A five months ethnography was conducted in each setting between March 2018 and March 2019. Data were collected through 127 hours of observations and interviews with 44 participants (learners, community workers and health professionals). Thematic analysis was performed to explore the impacts of the interventions and their interactions with local contexts.

Results

Preliminary findings indicate that learners' self-confidence, knowledge and skills for addressing local health determinants increased in both settings. However, contextual factors played an important role in supporting or hindering wider impacts in the communities where the initiatives were implemented. Opportunities for working together across sectors and being supported by local institutions were key elements supporting learners to transfer the acquired confidence, skills and knowledge to other settings beyond the time and space of the initiatives. These learners reported volunteering more in their communities, developing new activities, or transferring skills in their workplace to change practice and attitudes.

Conclusions

This study found that ABAs initiatives implemented in communities have the potential to support reduction of inequalities through increasing people's skills, knowledge and self-confidence. However, it is key to work intersectorally to create enabling environments where these acquired capacities can be mobilised, as the context can support or hinder wider changes to occur.

Key messages

Asset-based interventions to promote health increase people knowledge, skills and self-confidence, but it is key to consider how contextual factors can favour or hinder the potential for wider impacts. Community structures and institutional support for joint working influence mobilisation of learners’ acquired confidence, skills and knowledge beyond the formal spaces of asset-based interventions.

Reducing inequalities in child health: a case study in an English local authority

Background

Many health outcomes for children and young people in England, UK remain poor compared to international peers, with persistent inequalities across the country. Our study sought to understand, from the perspectives of local stakeholders, the key factors affecting the development and implementation of policy to improve child health and reduce inequalities.

Methods

We carried out a detailed case study in an English local authority area. Our fieldwork comprised: documentary review of local policies, observation of key strategic and operational meetings and semi-structured interviews with local stakeholders. We followed Jessop's (2016) approach in using specific policy areas and policies (mental health, obesity and the early years) as 'entry points' to understand the local context.

Results

First, and most importantly, there was an overriding consensus that local action to reduce inequalities in child health is hampered by a persistent unequal distribution of the social determinants of health. Second, local stakeholders highlighted the damaging impact of austerity measures and poverty in the UK, which, they argued, had impacted most upon the most vulnerable. Third, while national policies often provided a framework and incentive for local action, there was an emphasis on the importance of local knowledge and place-based approaches, developed through close work with communities.

Conclusions

Our study highlights the need for progressive policies to begin to reduce the uneven distribution of the social determinants of health to enable local stakeholders to make progress in tackling inequalities in child health. It emphasises the futility of funding national policies to improve child health and reduce inequalities in the context of greatly reduced budgets for local authorities. National policy should also facilitate the mobilisation of context specific knowledge, produced in conjunction with community members.

Key messages

Our work evidences the pressing need to address structural inequalities and adequately resource and facilitate work to reduce inequalities at a local level. National policy should facilitate the mobilisation of context specific knowledge, produced in conjunction with community members.

System-mapping the child health system at a local level to reduce health inequalities

Background

Systems thinking has emerged as a promising approach to addressing complex public health issues. For children, the focus of the approach has been on single outcomes e.g. obesity, rather than addressing the broad range of inequalities in health outcomes. We report on an approach to developing a system-oriented perspective on the determinants of inequalities in child health and wellbeing in English local authorities.

Methods

Qualitative group concept mapping workshops (a 'soft' system science approach) were held in two contrasting English local authorities with a range of stakeholders: professionals (N = 35); children and young people (N = 33) and carers (N = 5). Initial area maps were refined using data from qualitative interviews with professionals (N = 16) and resulting maps reviewed and validated by expert stakeholders in each area (N = 9; N = 35). Commonalities between two area-specific system maps (and removal of locality-specific factors) were used to develop a map that could be applied in any English local area. Two rounds of online consultation (N = 21; N = 8) and qualitative interviews (N = 12) with experts in public health, local governance and systems science refined the final system map displaying the determinants of child health inequalities, and give insight into its potential utilisation.

Results

The process created a map of over 150 factors influencing inequalities in health outcomes for children aged 0-25 years at the local area level. The system map has six domains; physical environment, governance, economic, social, service, and personal.

Conclusions

To our knowledge this is the first study taking a systems approach to addressing inequalities across all aspects of child health. Group concept mapping can support systems thinking at the local level. The resulting system map illustrates the complexity of factors influencing child health inequalities and is a useful tool for strategy development, action prioritisation and systems evaluation planning.

Key messages

Group concept mapping can be successfully applied to facilitate a systems approach to child health inequalities at the local area level. Mapping the local child health system highlights complex relationships between physical, social, personal, service, governance and economic factors which influence inequalities and health outcomes.

Skin Toxicity in Early Breast Cancer Patients Treated with Field-In-Field Breast Intensity-Modulated Radiotherapy versus Helical Inverse Breast Intensity-Modulated Radiotherapy: Results of a Phase III Randomised Controlled Trial

AIMS

Skin toxicity is a common adverse effect of breast radiotherapy. We investigated whether inverse-planned intensity-modulated radiotherapy (IMRT) would reduce the incidence of skin toxicity compared with forward field-in-field breast IMRT (FiF-IMRT) in early stage breast cancer.

MATERIALS AND METHODS

This phase III randomised controlled trial compared whole-breast irradiation with either FiF-IMRT or helical tomotherapy IMRT (HT-IMRT), with skin toxicity as the primary end point. Patients received 50 Gy in 25 fractions and were assessed to compare skin toxicity between treatment arms.

RESULTS

In total, 177 patients were available for assessment and the median follow-up was 73.1 months. Inverse IMRT achieved more homogeneous coverage than FiF-IMRT; erythema and moist desquamation were higher with FiF-IMRT compared with HT-IMRT (61% versus 34%; P < 0.001; 33% versus 11%; P < 0.001, respectively). Multivariate analysis showed large breast volume, FiF-IMRT and chemotherapy were independent factors associated with worse acute toxicity. There was no difference between treatment arms in the incidence of late toxicities. The 5-year recurrence-free survival was 96.3% for both FiF-IMRT and HT-IMRT and the 5-year overall survival was 96.3% for FiF-IMRT and 97.4% for HT-IMRT.

CONCLUSIONS

Our study showed significant reduction in acute skin toxicity using HT-IMRT compared with FiF-IMRT, without significant reduction in late skin toxicities. On the basis of these findings, inverse-planned IMRT could be used in routine practice for whole-breast irradiation with careful plan optimisation to achieve the required dose constraints for organs at risk.

The value of local registry data for describing cervical cancer management and outcomes over three decades in Australia

Registry data on invasive cervical cancers (n = 1,274) from four major hospitals (1984-2012) were analysed to determine their value for informing local service delivery in Australia. The methodology comprised disease-specific survival analyses using Kaplan-Meier product-limit estimates and Cox proportional hazards models and treatment analyses using logistic regression. Five- and 10-year survivals were 72% and 68%, respectively, equating with relative survival estimates for Australia and the USA. Most common treatments were surgery and radiotherapy. Systemic therapies increased in recent years, generally with radiotherapy, but were less common for residents from less accessible areas. Surgery was more common for younger women and early-stage disease, and radiotherapy for older women and regional and more advanced disease. The proportion of glandular cancers increased in-step with national trends. Little evidence of variation in risk-adjusted survival presented over time or by Local Health District. The study illustrates the value of local registry data for describing local treatment and outcomes. They show the lower use of systemic therapies among residents of less accessible areas which warrants further investigation. Risk-adjusted treatment and outcomes did not vary by socio-economic status, suggesting equity in service delivery. These data are important for local evaluation and were not available from other sources.

Assessing impact of organised breast screening across small residential areas-development and internal validation of a prediction model

Monitoring screening mammography effects in small areas is often limited by small numbers of deaths and delayed effects. We developed a risk score for breast cancer death to circumvent these limitations. Screening, if effective, would increase post-diagnostic survivals through lead-time and related effects, as well as mortality reductions. Linked cancer and BreastScreen data at four hospitals (n = 2,039) were used to investigate whether screened cases had higher recorded survivals in 13 small areas, using breast cancer deaths as the outcome (M1), and a risk of death score derived from TNM stage, grade, histology type, hormone receptor status, and related variables (M2). M1 indicated lower risk of death in screened cases in 12 of the 13 areas, achieving statistical significance (p < .05) in 5. M2 indicated lower risk scores in screened cases in all 13 areas, achieving statistical significance in 12. For cases recently screened at diagnosis (<6 months), statistically significant reductions applied in 8 areas (M1) and all 13 areas (M2). Screening effects are more detectable in small areas using these risk scores than death itself as the outcome variable. An added advantage is the application of risk scores for providing a marker of screening effect soon after diagnosis.

'Venus trapped, Mars transits': Cu and Fe redox chemistry, cellular topography and in situ ligand binding in terrestrial isopod hepatopancreas

Woodlice efficiently sequester copper (Cu) in ‘cuprosomes' within hepatopancreatic ‘S' cells. Binuclear ‘B’ cells in the hepatopancreas form iron (Fe) deposits; these cells apparently undergo an apocrine secretory diurnal cycle linked to nocturnal feeding. Synchrotron-based µ-focus X-ray spectroscopy undertaken on thin sections was used to characterize the ligands binding Cu and Fe in S and B cells of Oniscus asellus (Isopoda). Main findings were: (i) morphometry confirmed a diurnal B-cell apocrine cycle; (ii) X-ray fluorescence (XRF) mapping indicated that Cu was co-distributed with sulfur (mainly in S cells), and Fe was co-distributed with phosphate (mainly in B cells); (iii) XRF mapping revealed an intimate morphological relationship between the basal regions of adjacent S and B cells; (iv) molecular modelling and Fourier transform analyses indicated that Cu in the reduced Cu⁺ state is mainly coordinated to thiol-rich ligands (Cu–S bond length 2.3 Å) in both cell types, while Fe in the oxidized Fe³⁺ state is predominantly oxygen coordinated (estimated Fe–O bond length of approx. 2 Å), with an outer shell of Fe scatterers at approximately 3.05 Å; and (v) no significant differences occur in Cu or Fe speciation at key nodes in the apocrine cycle. Findings imply that S and B cells form integrated unit-pairs; a functional role for secretions from these cellular units in the digestion of recalcitrant dietary components is hypothesized.

Colorectal cancer treatment and survival over three decades at four major public hospitals in South Australia: trends by age and in the elderly

Data from registries at four major public hospitals in South Australia indicate increased 5-year disease-specific survivals for colorectal cancer from 48% to 63% between 1980-1986 and 2005-2010. For 80+ year olds, the increase was smaller, from 47% to 52%. Risk of case fatality halved overall, adjusting for age, gender, stage, differentiation and sub-site. Patients aged 80+ years had a lower risk reduction of about a third (hazards ratio: 0.69; 95% confidence limits, 0.52-0.92). Percentages having surgery and other specified treatments were lower for 80+ year olds than younger cases, although increases in treatment intensity occurred in this age range during 1980-2010, as seen in younger ages, in accordance with guidelines. The study illustrates the important feedback clinical registries can provide to clinicians on care patterns and outcomes in their hospital settings. Feedback can be the subject of local deliberations on how to achieve the best outcomes, including in the elderly by considering the best trade-offs between optimal cancer care and accommodations for co-morbidity and frailty. Clinical registry data can be used in comparative effectiveness research in local settings where there are sufficient case numbers.

Tuberculosis among the homeless, United States, 1994-2010

OBJECTIVES

1) To describe homeless persons diagnosed with tuberculosis (TB) during the period 1994-2010, and 2) to estimate a TB incidence rate among homeless persons in the United States.

METHODS

TB cases reported to the National Tuberculosis Surveillance System were analyzed by origin of birth. Incidence rates were calculated using the US Department of Housing and Urban Development homeless population estimates. Analysis of genotyping results identified clustering as a marker for transmission among homeless TB patients.

RESULTS

Of 270,948 reported TB cases, 16,527 (6%) were homeless. The TB incidence rate among homeless persons ranged from 36 to 47 cases per 100,000 population in 2006-2010. Homeless TB patients had over twice the odds of not completing treatment and of belonging to a genotype cluster. US- and foreign-born homeless TB patients had respectively 8 and 12 times the odds of substance abuse.

CONCLUSIONS

Compared to the general population, homeless persons had an approximately 10-fold increase in TB incidence, were less likely to complete treatment and more likely to abuse substances. Public health outreach should target homeless populations to reduce the excess burden of TB in this population.

A double-blind, randomized, placebo-controlled, parallel-group study of Sativex, in subjects with symptoms of spasticity due to multiple sclerosis

BACKGROUND

Muscle spasticity is common in multiple sclerosis (MS), occurring in more than 60% of patients.

OBJECTIVE

To compare Sativex with placebo in relieving symptoms of spasticity due to MS.

METHODS

A 15-week, multicenter, double-blind, randomized, placebo-controlled, parallel-group study in 337 subjects with MS spasticity not fully relieved with current anti-spasticity therapy.

RESULTS

The primary endpoint was a spasticity 0-10 numeric rating scale (NRS). Intention-to-treat (ITT) analysis showed a non-significant improvement in NRS score, in favor of Sativex. The per protocol (PP) population (79% of subjects) change in NRS score and responder analyses (> or =30% improvement from baseline) were both significantly superior for Sativex, compared with placebo: -1.3 versus -0.8 points (change from baseline, p=0.035); and 36% versus 24% (responders, p=0.040). These were supported by the time to response (ITT: p=0.068; PP: p=0.025) analyses, carer global impression of change assessment (p=0.013) and timed 10-meter walk (p=0.042). Among the subjects who achieved a > or =30% response in spasticity with Sativex, 98, 94 and 73% reported improvements of 10, 20 and 30%, respectively, at least once during the first 4 weeks of treatment. Sativex was generally well tolerated, with most adverse events reported being mild-to-moderate in severity.

DISCUSSION AND CONCLUSIONS

The 0-10 NRS and responder PP analyses demonstrated that Sativex treatment resulted in a significant reduction in treatment-resistant spasticity, in subjects with advanced MS and severe spasticity. The response observed within the first 4 weeks of treatment appears to be a useful aid to prediction of responder/non-responder status.

Semi-automated segmentation to assess the lateral meniscus in normal and osteoarthritic knees

OBJECTIVE

The goal of this study was to develop an algorithm to semi-automatically segment the meniscus in a series of magnetic resonance (MR) images to use for normal knees and those with moderate osteoarthritis (OA).

METHOD

The segmentation method was developed then evaluated on 10 baseline MR images obtained from subjects with no evidence, symptoms, or risk factors of knee (OA), and 14 from subjects with established knee OA enrolled in the Osteoarthritis Initiative (OAI). After manually choosing a seed point within the meniscus, a threshold level was calculated through a Gaussian fit model. Under anatomical, intensity, and range constraints, a threshold operation was completed followed by conditional dilation and post-processing. The post-processing operation reevaluates the pixels included and excluded in the area surrounding the meniscus to improve accuracy. The developed method was evaluated for both normal and degenerative menisci by comparing the segmentation algorithm results with manual segmentations from five human readers.

RESULTS

The semi-automated segmentation method produces results similar to those of trained observers, with an average similarity index over 0.80 for normal participants and 0.75, 0.67, and 0.64 for participants with established knee OA with Osteoarthritis Research Society International (OARSI) joint space narrowing (JSN) scores of 0, one, and two respectively.

CONCLUSION

The semi-automatic segmentation method produced accurate and consistent segmentations of the meniscus when compared to manual segmentations in the assessment of normal menisci in mild to moderate OA. Future studies will examine the change in volume, thickness, and intensity characteristics at different stages of OA.

Weakness in pregnancy - expect the unexpected

Guillain-Barré syndrome (GBS) is rare in pregnancy with an incidence estimated to be between 1.2 and 1.9 cases per 100,000 people annually, and it is generally accepted that it carries a high maternal risk. Delayed diagnosis is common because the initial non-specific symptoms may mimic changes in pregnancy. GBS should be considered in any pregnant patient complaining of muscle weakness, general malaise, tingling of the fingers and respiratory discomfort. This case aims to highlight the importance of early diagnosis, allowing prompt initiation of the immunomodulatory treatments which have been shown to improve outcome alongside multidisciplinary care.

Low tidal volume ventilation is associated with reduced mortality in HIV-infected patients with acute lung injury

BACKGROUND

Respiratory failure remains the leading indication for admission to the intensive care unit (ICU) and a leading cause of death for HIV-infected patients in spite of overall improvements in ICU mortality. It is unclear if these improvements are due to combination anti-retroviral therapy, low tidal volume ventilation for acute lung injury, or both. A study was undertaken to identify therapies and clinical factors associated with mortality in acute lung injury among HIV-infected patients with respiratory failure in the period 1996-2004. A secondary aim was to compare mortality before and after introduction of a low tidal volume ventilation protocol in 2000.

METHODS

A retrospective cohort study was performed of 148 consecutive HIV-infected adults admitted to the ICU at San Francisco General Hospital with acute lung injury requiring mechanical ventilation. Demographic and clinical information including data on mechanical ventilation was abstracted from medical records and analysed by multivariate analysis using logistic regression.

RESULTS

In-hospital mortality was similar before and after introduction of a low tidal volume ventilation protocol, although the study was not powered to exclude a clinically significant difference (risk difference -5.4%, 95% CI -21% to 11%, p = 0.51). Combination antiretroviral therapy was not clearly associated with mortality, except in patients with Pneumocystis pneumonia. Among all those with acute lung injury, lower tidal volume was associated with decreased mortality (adjusted odds ratio 0.76 per 1 ml/kg decrease, 95% CI 0.58 to 0.99, p = 0.043), after controlling for Pneumocystis pneumonia, serum albumin, illness severity, gas exchange impairment and plateau pressure.

CONCLUSIONS

Lower tidal volume ventilation is independently associated with reduced mortality in HIV-infected patients with acute lung injury and respiratory failure.

Hereditary angioedema and pregnancy

Hereditary Angioedema is a rare but potentially life threatening condition. It is important that Obstetricians are aware of this condition as it affects women in the reproductive years and thus its recognition and proper management in pregnancy is crucial.

Necrotizing neurosarcoid: three cases with varying presentations

BACKGROUND

Neurosarcoid affects approximately 5% of patients with sarcoidosis. A significantly more rare entity, necrotizing sarcoidosis affecting the central nervous system, has been confirmed previously in only three case reports. This paper documents three additional cases of necrotizing neurosarcoid, involving a wide spectrum of central nervous system (CNS) locations.

RESULTS

One patient presented to the emergency department after being found unresponsive. The second patient was referred due to hearing loss and the third patient sought care due to weakness and numbness of his left lower extremity. Locations of involvement were diverse and included diffuse leptomeningeal involvement, a cerebellopontine angle mass and a thoracic spinal cord lesion. All patients eventually underwent surgical biopsy, and histologic review of tissue samples revealed necrotizing granulomatous inflammation. Serum ACE levels were available for two of the patients and were within normal limits. Once the diagnosis of necrotizing neurosarcoid was confirmed, all patients were treated with systemic corticosteroid therapy; one patient was also treated with an immunosuppressive agent.

CONCLUSIONS

Necrotizing neurosarcoid may occur more commonly than previously described and should be considered in the differential diagnosis of patients without systemic manifestations of sarcoidosis.