Severity of oEsophageal Anastomotic Leak in patients after oesophagectomy: the SEAL score

Background

Anastomotic leak (AL) is a common but severe complication after oesophagectomy. It is unknown how to determine the severity of AL objectively at diagnosis. Determining leak severity may guide treatment decisions and improve future research. This study aimed to identify leak-related prognostic factors for mortality, and to develop a Severity of oEsophageal Anastomotic Leak (SEAL) score.

Methods

This international, retrospective cohort study in 71 centres worldwide included patients with AL after oesophagectomy between 2011 and 2019. The primary endpoint was 90-day mortality. Leak-related prognostic factors were identified after adjusting for confounders and were included in multivariable logistic regression to develop the SEAL score. Four classes of leak severity (mild, moderate, severe, and critical) were defined based on the risk of 90-day mortality, and the score was validated internally.

Results

Some 1509 patients with AL were included and the 90-day mortality rate was 11.7 per cent. Twelve leak-related prognostic factors were included in the SEAL score. The score showed good calibration and discrimination (c-index 0.77, 95 per cent c.i. 0.73 to 0.81). Higher classes of leak severity graded by the SEAL score were associated with a significant increase in duration of ICU stay, healing time, Comprehensive Complication Index score, and Esophagectomy Complications Consensus Group classification.

Conclusion

The SEAL score grades leak severity into four classes by combining 12 leak-related predictors and can be used to the assess severity of AL after oesophagectomy.

Clinical Relevance of the Tumor Location-Modified Laurén Classification System for Gastric Cancer in a Western Population

Background

The Tumor Location-Modified Laurén Classification (MLC) system combines Laurén histologic subtype and anatomic tumor location. It divides gastric tumors into proximal non-diffuse (PND), distal non-diffuse (DND), and diffuse (D) types. The optimum classification of patients with Laurén mixed tumors in this system is not clear due to its grouping with both diffuse and non-diffuse types in previous studies. The clinical relevance of the MLC in a Western population has not been examined.

Methods

A cohort study investigated 404 patients who underwent gastrectomy for gastric adenocarcinoma between 2005 and 2020. The classification of Laurén mixed tumors was evaluated using receiver operating characteristic (ROC) curve analysis and comparison of clinicopathologic characteristics (chi-square). Survival analysis was performed using multivariable Cox regression.

Results

The ROC curve analysis demonstrated a slightly higher area under the curve value for predicting survival when Laurén mixed tumors were grouped with intestinal-type rather than diffuse-type tumors (0.58 vs 0.57). Survival, tumor recurrence, and resection margin positivity in mixed tumors also was more similar to intestinal type. Distal non-diffuse tumors had the best 5-year survival (DND 64.7 % vs PND 56.1 % vs diffuse 45.1 %; p = 0.006) and were least likely to have recurrence (DND 27.0 % vs PND 34.3 % vs diffuse 48.3 %; p = 0.001). Multivariable analysis demonstrated that MLC was an independent prognostic factor for survival (PND: hazard ratio [HR], 1.64; 95 % confidence interval [CI], 1.16–2.32 vs diffuse: HR, 2.20; 95 % CI, 1.56–3.09)

Conclusions

The MLC was an independent prognostic marker in this Western cohort of patients with gastric adenocarcinoma. The patients with PND and D tumors had worse survival than those with DND tumors.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-021-11252-y.

Learning lessons from the community response to COVID-19 in Wales

Background

During the pandemic, community action sprang up in response to the health and social consequences of the virus. Communities were driven to support each other and those perceived as vulnerable. Community support and social capital are key for strengthening resilience, and an important contributor to population health. The aim was to explore what factors enabled community-led action in response to need amongst the most deprived areas in Wales during COVID-19.

Methods

Mixed-methods approach, with a strong focus on qualitative research with a systems-lens. Quantitative data was collected through a survey of 2500 adults >18 years; living, working or volunteering in Wales engaged in community action, and analysed descriptively. Outcomes were motivation, benefits, current and past activities, barriers, socio-economic characteristics [age, education, employment, postcode], digital volunteerism, resilience [RRC-ARM 12], and health and wellbeing [WEMWBS-14]. Qualitative data was collected in two communities in South Wales from 46 semi-structured interviews with recipients, volunteers, and strategic leads and analysed thematically. This explored determinants and experience of community-led action, levers and drivers, and integration with the wider system.

Results

Results are preliminary. They include individual-level factors underlying volunteerism and pro-social behaviour across different categories of volunteer (unstructured, informal, formal) and across national area-level deprivation indicators (WIMD), and perspectives across the system on community-led response and its role in community empowerment in supporting the vulnerable within communities.

Conclusions

Improved understanding of the role of community-led action as a protective factor against widening health inequalities during, and in recovery from COVID-19, was brought together to develop and coproduce a framework to empower community-led action and support sustainable integration with existing services.

Key messages

Understanding how community-led action sustained and be better supported and integrated into the health, third sector and social support system is important for building resilient communities.

Understanding community-led action during COVID-19 will inform how this can best supported to help protect against the longer-term differences in the health, social and economic impact.

A mixed methods study of lived experiences of homelessness in Wales and childhood adversity

Background

Homelessness is a serious and complex societal and public health issue with multiple causes and solutions. Dealing with homelessness involves both supporting people at risk of homelessness and addressing personal and structural causes occurring through the life-course, including Adverse Childhood Experiences (ACEs). We examine the relationship between ACEs and homelessness in Wales, and consider priority areas for early intervention and prevention.

Methods

Data was retrospectively analysed from a 2017 cross-sectional national 2017 (n = 2452) of adults aged 16-69 years living in Wales using a stratified random probability sampling methodology. Outcome measures included number of ACEs, lifetime homelessness, and childhood resilience assets and were analysed using bivariate statistics. Pathways interviews with people experiencing homelessness (n = 27) and services (n = 16) explored experiences and views, and were analysed thematically.

Results

Homelessness affects 1 in 14 (7%) of the Welsh population in their lifetime. 87% of those with lived experience of homelessness had experienced at least one ACE compared with a Welsh average of 46%; and 50% of those with lived experience of homelessness had experienced 4+ ACEs, compared to 11% in the wider population. Compared with those with no ACEs, individuals with 4+ ACEs were 16 times more likely to report experiencing homelessness (95% CI 9.73,26.43), but Childhood Resilience Assets were protective reducing this by half (adjusted odds ratio 8.073, 95% CI 4.68,13.93). From interviews, early years/schools are critical in supporting children with ACEs, and services through the life-course need to be ACE-aware and better able to cope with impacts of ACEs.

Conclusions

A clear association is seen between ACEs and homelessness. Early intervention that prevents ACEs is needed, as well as better addressing support needs of both child and adult vulnerable populations to prevent homelessness and intervene earlier.

Key messages

In a national Welsh study, 87% of those reporting lived experience of homelessness had experienced at least one adverse childhood experience (ACE), and 50% reported four or more ACEs. Early intervention that prevents ACEs, combined with a trauma-informed approach that builds resilience in at-risk children and adults, is likely to contribute to reducing and preventing homelessness.

Supporting farmer and fisher communities in Wales through uncertainty: two mixed methods studies

Background

Rural, farming and fishing communities in Wales were highlighted as vulnerable to uncertainty and change from Brexit, with likely impacts to mental health and wellbeing in these groups. Policy needs to understand how to prevent challenges, protect against health impacts, and promote mental health and wellbeing in these hard-to-reach/engage groups using evidence-based solutions.

Methods

Two mixed-methods studies were undertaken in 2019-20, using identical methodologies, one in farming and one in fishing communities. For both, MEDLINE, Embase, PsycINFO, NICE, and Cochrane databases were searched for keywords associated with farmers/fishers, mental health, wellbeing, resilience, support, and suicide; for studies of any design published in English, in 2005-19. Evidence was further supported by stakeholder engagement through two world café workshops in each group (farmers n = 19, fishers n = 13). For farmers, additional face-to-face and telephone consultation took place (n = 26). Challenges, existing support, and relevance of the evidence review were examined. Engagement was recorded through researcher's field notes and analysed thematically.

Results

For farmers, 843 records were identified after duplicated removed, screened, 130 full text records examined, and 14 interventions included. For fishers, 415 records identified, 135 full text examined, and 7 interventions included. Evidence-based programmes supporting farmers were centred on health promotion, mental health literacy, and cross-agency partnership development; and for fishers, support was centred solely on health promotion. Qualitative engagement uncovered challenges faced in Wales, barriers to seeking support, and assets available to each group.

Conclusions

The evidence from the review and engagement was brought together to create action frameworks for supporting both farmers and fishers in Wales, centred on prevention, protection, and promotion of mental health and wellbeing.

Key messages

Farming and fishing are contributors to Wales’ rural economy and cultural identity. A strong evidence-base of how to support mental health of these groups is vital to help them cope with change. Action for supporting both farmers and fishers in Wales should be centred on prevention, protection, and promotion of mental health and wellbeing.

Differences in the impact of precarious employment on health across population subgroups: a scoping review

Aim:

Precarious employment is known to be detrimental to health, and some population subgroups (young individuals, migrant workers, and females) are at higher risk of precarious employment. However, it is not known if the risk to poor health outcomes is consistent across population subgroups. This scoping review explores differential impacts of precarious employment on health.

Methods:

Relevant studies published between 2009 and February 2019 were identified across PubMed, OVID Medline, PsycINFO, and Scopus. Articles were included if (1) they presented original data, (2) examined precarious employment within one of the subpopulations of interest, and (3) examined health outcomes.

Results:

Searches yielded 279 unique results, of which 14 met the eligibility criteria. Of the included studies, 12 studies examined differences between gender, 3 examined the health impacts on young individuals, and 3 examined the health of migrant workers. Mental health was explored in nine studies, general health in four studies, and mortality in two studies.

Conclusion:

Mental health was generally poorer in both male and female employees as a result of precarious employment, and males were also at higher risk of mortality. There was limited evidence that met our inclusion criteria, examining the health impacts on young individuals or migrant workers.

Laparoscopic-assisted left thoracoabdominal esophagectomy (LLTA): an innovative approach for locally advanced tumors of the gastroesophageal junction

PURPOSE

To report a novel approach for locally advanced tumors located at the gastroesophageal junction (GEJ) using a laparoscopic abdominal phase and open left thoracotomy with the patient in a single right lateral decubitus position.

BACKGROUND

The standard open left thoracoabdominal approach offers excellent exposure and access to the GEJ and lower esophagus. It also involves a single position for the procedure, shortening the operation time. The disadvantages are a large incision, division of the costochondral junction, and a low-level thoracotomy. The laparoscopic-assisted left thoracoabdominal esophagectomy (LLTA) is performed with the patient in the same right lateral decubitus position, but initially rolled away from the operator at 45° allowing laparoscopic gastric mobilization and lymphadenectomy. The patient is then tilted back to the lateral position for the thoracic phase. An anterolateral left thoracotomy is performed through the higher fifth intercostal space allowing a high intrathoracic anastomosis, just below the aortic arch. No disruption of the costochondral junction is made.

METHODS

Consecutive patients selectively treated for locally advanced GEJ tumors with an LLTA approach between 2013 and 2019 were analyzed and compared to national standards (NOGCA).

RESULTS

This series of 74 consecutive patients had a mean age of 63 years. The median operation time was 235 minutes. The median inpatient stay was 10 days (NOGCA 9 [11-17]). The tumors were predominantly adenocarcinoma (95%) and located at the GEJ (92%). The majority were locally advanced T3 or T4 tumors. Postoperative morbidity was low, Clavien-Dindo (C-D) 0 in 52.7% patients, C-D1 (1.4%), C-D2 (31.1%), C-D3a (5.4%), C-D4a (9.5%), and C-D5 (1.4%). The median number of total lymph nodes (LN) excised was 28 (NOGCA >15); LN % yield ≥18 was 90% (NOGCA 82.5%). Positive nodes were located at the lesser-curve (40%), paraesophageal (32.4%), and subcarinal regions (2.7%). Positive circumferential resection margins (<1 mm) were present in 28.4% of resected specimens (NOGCA 25.1%). This is reflective of the high proportion T3/T4 tumors selected for this approach. Hospital and 30-day mortality was 1.4% (NOGCA 2.7%). Recurrence after LLTA was 25.7% (local 5.4%, systemic 17.6%, mixed 2.7%) at a median of 311 days (62-1,158).

CONCLUSION

This series demonstrates a novel, safe, and reproducible approach for locally advanced cancer of the GEJ. It offers a better exposure of the hiatus than the right-sided approach and avoids division of the costochondral junction and low thoracotomy seen with the open left thoracoabdominal approach.

Adjuvant therapy following oesophagectomy for adenocarcinoma in patients with a positive resection margin

BACKGROUND

The role of adjuvant therapy in patients with oesophagogastric adenocarcinoma treated by neoadjuvant chemotherapy is contentious. In UK practice, surgical resection margin status is often used to classify patients for receiving adjuvant treatment. The aim of this study was to assess the survival benefit of adjuvant therapy in patients with positive (R1) resection margins.

METHODS

Two prospectively collected UK institutional databases were combined to identify eligible patients. Adjusted Cox regression analyses were used to compare overall and recurrence-free survival according to adjuvant treatment. Recurrence patterns were assessed as a secondary outcome. Propensity score-matched analysis was also performed.

RESULTS

Of 616 patients included in the combined database, 242 patients who had an R1 resection were included in the study. Of these, 112 patients (46·3 per cent) received adjuvant chemoradiotherapy, 46 (19·0 per cent) were treated with adjuvant chemotherapy and 84 (34·7 per cent) had no adjuvant treatment. In adjusted analysis, adjuvant chemoradiotherapy improved recurrence-free survival (hazard ratio (HR) 0·59, 95 per cent c.i. 0·38 to 0·94; P = 0·026), with a benefit in terms of both local (HR 0·48, 0·24 to 0·99; P = 0·047) and systemic (HR 0·56, 0·33 to 0·94; P = 0·027) recurrence. In analyses stratified by tumour response to neoadjuvant chemotherapy, non-responders (Mandard tumour regression grade 4-5) treated with adjuvant chemoradiotherapy had an overall survival benefit (HR 0·61, 0·38 to 0·97; P = 0·037). In propensity score-matched analysis, an overall survival benefit (HR 0·62, 0·39 to 0·98; P = 0·042) and recurrence-free survival benefit (HR 0·51, 0·30 to 0·87; P = 0·004) were observed for adjuvant chemoradiotherapy versus no adjuvant treatment.

CONCLUSION

Adjuvant therapy may improve overall survival and recurrence-free survival after margin-positive resection. This pattern seems most pronounced with adjuvant chemoradiotherapy in non-responders to neoadjuvant chemotherapy.

Health and mass unemployment events-developing a framework for preparedness and response

BACKGROUND

Mass unemployment events are not uncommon yet the impact on health is not well recognised. There is a need for a preparedness and response framework, as exists for other events that threaten population health.

METHODS

Framework informed by a narrative review of the impact of mass unemployment on health (studies published in English from 1990 to 2016), and qualitative data from 23 semi-structured interviews with individuals connected to historical national and international events, addressing gaps in published literature on lessons learnt from past responses.

RESULTS

Economic and employment shock triggered by mass unemployment events have a detrimental impact on workers, families and communities. We present a public health informed response framework which includes (i) identify areas at risk, (ii) develop an early warning system, (iii) mobilise multi-sector action including health and community, (iv) provision of support across employment, finance and health (v) proportionate to need, (vi) extend support to family members and (vii) communities and (viii) evaluate and learn.

CONCLUSION

Mass unemployment events have an adverse impact on the health, financial and social circumstances of workers, families, and communities. This is the first framework for action to mitigate and address the detrimental impact of mass unemployment events on population health.

Prediction of a positive circumferential resection margin at surgery following neoadjuvant chemotherapy for adenocarcinoma of the oesophagus

Background

A positive circumferential resection margin (CRM) has been associated with higher rates of locoregional recurrence and worse survival in oesophageal cancer. The aim of this study was to establish if clinicopathological and radiological variables might predict CRM positivity in patients who received neoadjuvant chemotherapy before surgery for oesophageal adenocarcinoma.

Methods

Multivariable analysis of clinicopathological and CT imaging characteristics considered potentially predictive of CRM was performed at initial staging and following neoadjuvant chemotherapy. Prediction models were constructed. The area under the curve (AUC) with 95% confidence intervals (c.i.) from 1000 bootstrapping was assessed.

Results

A total of 223 patients were included in the study. Poor differentiation (odds ratio (OR) 2·84, 95 per cent c.i. 1·39 to 6·01) and advanced clinical tumour status (T3-4) (OR 2·93, 1·03 to 9·48) were independently associated with an increased CRM risk at diagnosis. CT-assessed lack of response (stable or progressive disease) following chemotherapy independently corresponded with an increased risk of CRM positivity (OR 3·38, 1·43 to 8·50). Additional CT evidence of local invasion and higher CT tumour volume (14 cm3) improved the performance of a prediction model, including all the above parameters, with an AUC (c-index) of 0·76 (0·67 to 0·83). Variables associated with significantly higher rates of locoregional recurrence were pN status (P = 0·020), lymphovascular invasion (P = 0·007) and poor response to chemotherapy (Mandard score 4-5) (P = 0·006). CRM positivity was associated with a higher locoregional recurrence rate, but this was not statistically significant (P = 0·092).

Conclusion

The presence of advanced cT status, poor tumour differentiation, and CT-assessed lack of response to chemotherapy, higher tumour volume and local invasion can be used to identify patients at risk of a positive CRM following neoadjuvant chemotherapy.

A seven-Gene Signature assay improves prognostic risk stratification of perioperative chemotherapy treated gastroesophageal cancer patients from the MAGIC trial

Background

Following neoadjuvant chemotherapy for operable gastroesophageal cancer, lymph node metastasis is the only validated prognostic variable; however, within lymph node groups there is still heterogeneity with risk of relapse. We hypothesized that gene profiles from neoadjuvant chemotherapy treated resection specimens from gastroesophageal cancer patients can be used to define prognostic risk groups to identify patients at risk for relapse.

Patients and methods

The Medical Research Council Adjuvant Gastric Infusional Chemotherapy (MAGIC) trial (n = 202 with high quality RNA) samples treated with perioperative chemotherapy were profiled for a custom gastric cancer gene panel using the NanoString platform. Genes associated with overall survival (OS) were identified using penalized and standard Cox regression, followed by generation of risk scores and development of a NanoString biomarker assay to stratify patients into risk groups associated with OS. An independent dataset served as a validation cohort.

Results

Regression and clustering analysis of MAGIC patients defined a seven-Gene Signature and two risk groups with different OS [hazard ratio (HR) 5.1; P < 0.0001]. The median OS of high- and low-risk groups were 10.2 [95% confidence interval (CI) of 6.5 and 13.2 months] and 80.9 months (CI: 43.0 months and not assessable), respectively. Risk groups were independently prognostic of lymph node metastasis by multivariate analysis (HR 3.6 in node positive group, P = 0.02; HR 3.6 in high-risk group, P = 0.0002), and not prognostic in surgery only patients (n = 118; log rank P = 0.2). A validation cohort independently confirmed these findings.

Conclusions

These results suggest that gene-based risk groups can independently predict prognosis in gastroesophageal cancer patients treated with neoadjuvant chemotherapy. This signature and associated assay may help risk stratify these patients for post-surgery chemotherapy in future perioperative chemotherapy-based clinical trials.

Lymph node regression and survival following neoadjuvant chemotherapy in oesophageal adenocarcinoma

BACKGROUND

The aim was to define the pathological response in lymph nodes following neoadjuvant chemotherapy for oesophageal adenocarcinoma and to quantify any associated survival benefit.

METHODS

Lymph nodes retrieved at oesophagectomy were examined retrospectively by two pathologists for evidence of a response to chemotherapy. Patients were classified as lymph node-negative (either negative nodes with no evidence of previous tumour involvement or negative with evidence of complete regression) or positive (allocated a lymph node regression score based on the proportion of fibrosis to residual tumour). Lymph node responders (score 1, complete response; 2, less than 10 per cent remaining tumour; 3, 10-50 per cent remaining tumour) and non-responders (score 4, more than 50 per cent viable tumour; 5, no response) were compared in survival analyses using Kaplan-Meier and Cox regression analysis.

RESULTS

Among 377 patients, 256 had neoadjuvant chemotherapy. Overall, 68 of 256 patients (26·6 per cent) had a lymph node response and 115 (44·9 per cent) did not. The remaining 73 patients (28·5 per cent) had negative lymph nodes with no evidence of regression. Some patients had a lymph node response in the absence of a response in the primary tumour (27 of 99, 27 per cent). Lymph node responders had a significant survival benefit (P < 0·001), even when stratified by patients with or without a response in the primary tumour. On multivariable analysis, lymph node responders had decreased overall (hazard ratio 0·53, 95 per cent c.i. 0·36 to 0·78) and disease-specific (HR 0·42, 0·27 to 0·66) mortality, and experienced reduced local and systemic recurrence.

CONCLUSION

Lymph node regression is a strong prognostic factor and may be more important than response in the primary tumour.

Impact of incremental circumferential resection margin distance on overall survival and recurrence in oesophageal adenocarcinoma

Background

Previous analyses of the oesophageal circumferential resection margin (CRM) have focused on the prognostic validity of two different definitions of a positive CRM, that of the College of American Pathologists (tumour at margin) and that of the Royal College of Pathologists (tumour within 1 mm). This study aimed to analyse the validity of these definitions and explore the risk of recurrence and survival with incremental tumour distances from the CRM.

Methods

This cohort study included patients who underwent resection for adenocarcinoma of the oesophagus between 2000 and 2014. Kaplan-Meier and Cox regression analyses were performed to determine the hazard ratio (HR) with 95 per cent confidence intervals for recurrence and mortality in CRM increments: tumour at the cut margin, extending to within 0·1-0·9, 1·0-1·9, 2·0-4·9 mm, and 5·0 mm or more from the margin.

Results

A total of 444 patients were included in the study. Kaplan-Meier and unadjusted analyses showed a significant incremental improvement in overall survival (P < 0·001) and recurrence (P for trend < 0·001) rates with increasing distance from the CRM. Tumour distance of 2·0 mm or more remained a significant predictor of survival on multivariable analysis (HR for risk of death 0·66, 95 per cent c.i. 0·44 to 1·00). Multivariable analysis of overall survival demonstrated a significant difference between a positive and negative CRM with the Royal College of Pathologists' definition (HR 1·37, 1·01 to 1·85), but not with the College of American Pathologists' definition (HR 1·22, 0·90 to 1·65).

Conclusion

This study demonstrated an incremental improvement in survival and recurrence rates with increasing tumour distance from the CRM.

Patterns of recurrence in oesophageal cancer following oesophagectomy in the era of neoadjuvant chemotherapy

Background

Tumour recurrence following oesophagectomy for oesophageal cancer is common despite neoadjuvant treatment. Understanding patterns of recurrence and risk factors associated with locoregional and systemic recurrence might influence future treatment strategies.

Methods

This was a cohort study involving patients undergoing resection for adenocarcinoma or squamous cell carcinoma of the oesophagus between 2000 and 2014. Clinicopathological factors associated with locoregional and systemic recurrence were analysed using multivariable logistic regression to determine odds ratios (ORs) and 95 per cent confidence intervals.

Results

Some 698 patients were identified. Lymphovascular invasion (OR 2·09, 95 per cent c.i. 1·18 to 3·71) and preoperative stenting (OR 3·70, 1·34 to 10·23) were independent risk factors for isolated locoregional recurrence. Pathological nodal disease in patients with pT1–2 (pN1: OR 2·72, 1·35 to 5·48; pN2–3: OR 5·00, 2·35 to 10·66) or pT3–4 (pN1: OR 3·03, 1·51 to 6·07; pN2–3: OR 5·75, 3·15 to 10·49) disease predisposed to systemic recurrence. Poor or no response to chemotherapy was also an independent risk factor for isolated systemic recurrence (OR 1·85, 1·05 to 3·26). A positive resection margin (R1 resection) was not associated with a significantly increased risk of isolated locoregional recurrence (OR 1·37, 0·81 to 2·33).

Conclusion

These findings confirm that oesophageal adenocarcinoma is frequently a systemic disease. Understanding the key predictors of local and systemic recurrence may facilitate the tailoring of oncological therapies to the individual patient.

A comparison of the left thoracoabdominal and Ivor-Lewis esophagectomy

The purpose of this study was to assess the oncological outcomes of a large multicenter series of left thoracoabdominal esophagectomies, and compare these to the more widely utilized Ivor-Lewis esophagectomy. With ethics approval and an established study protocol, anonymized data from five centers were merged into a structured database. The study exposure was operative approach (ILE or LTE). The primary outcome measure was time to death. Secondary outcome measures included time to tumor recurrence, positive surgical resection margins, lymph node yield, postoperative death, and hospital length of stay. Cox proportional hazards models provided hazard ratios (HR) with 95% confidence intervals (CI) adjusting for age, pathological tumor stage, tumor grade, lymphovascular invasion, and neoadjuvant treatment. Among 1228 patients (598 ILE; 630 LTE), most (86%) had adenocarcinoma (AC) and were male (81%). Comparing ILE and LTE for AC patients, no difference was seen in terms of time to death (HR 0.904 95%CI 0.749-1.1090) or time to recurrence (HR 0.973 95%CI 0.768-1.232). The risk of a positive resection margin was also similar (OR 1.022 95%CI 0.731-1.429). Median lymph node yield did not differ between approaches (LTE 21; ILE 21; P = 0.426). In-hospital mortality was 2.4%, significantly lower in the LTE group (LTE 1.3%; ILE 3.6%; P = 0.004). Median hospital stay was 11 days in the LTE group and 14 days in the ILE group (P < 0.0001). In conclusion, this is the largest series of left thoracoabdominal esophagectomies to be submitted for publication and the only one to compare two different transthoracic esophagectomy strategies. It demonstrates oncological equivalence between operative approaches but possible short- term advantages to the left thoracoabdominal esophagectomy.

Health-related quality of life after open transhiatal and transthoracic oesophagectomy for cancer

Background

Transhiatal and transthoracic oesophagectomy in patients with oesophageal cancer have similar survival rates. Whether these approaches differ in health-related quality of life (HRQoL) is uncertain and was examined in this study.

Methods

Patients undergoing transhiatal or transthoracic surgery for lower-third oesophageal or gastro-oesophageal junctional cancer between 2011 and 2015 were selected from an institutional database. HRQoL outcomes were measured at 6 and 12 months after surgery using validated written questionnaires (European Organisation for Research and Treatment of Cancer QLQ-C30 and QLQ-OG25). Linear mixed models provided mean score differences (MSDs) with 95 per cent confidence intervals, adjusted for preoperative HRQoL, age, physical status (ASA fitness grade), tumour location, tumour stage, neoadjuvant therapy, adjuvant therapy and postoperative complications. MSD values of 10 or more were regarded as clinically relevant.

Results

Some 146 patients underwent transhiatal (86, 58·9 per cent) or transthoracic (60, 41·1 per cent) oesophagectomy. The HRQoL questionnaires were returned by 111 patients at 6 months and 74 at 12 months. At 6 months, transthoracic oesophagectomy was associated with worse role function (MSD –12, 95 per cent c.i. –23 to 0; P = 0·046). At 12 months, patients in the transthoracic group had more nausea and vomiting (MSD 11, 0 to 22; P = 0·045), dyspnoea (MSD 13, 1 to 25; P = 0·029) and constipation (MSD 20, 7 to 33; P = 0·003) than those in the transhiatal group.

Conclusion

Transhiatal oesophagectomy seems to offer better HRQoL than transthoracic oesophagectomy 6 and 12 months after surgery.

A national audit of colonic interposition for esophageal replacement

Esophageal replacement by colonic interposition is an uncommon procedure. This study sought to identify the frequency of this operation in England, identify techniques and associated problems, and also assess health-related quality of life (HR QOL) from the two largest centers performing this procedure. Hospital Episode Statistics were used to identify patients and centers undertaking colon interposition between March 2001 and March 2015. An online survey of UK consultants discussed methods and experience. HR QOL was assessed using the Short Form 36(SF-36v2) with additional gastrointestinal questions. Hospital Episode Statistics identified 328 interpositions (22 in pediatric hospitals). The two highest volume units did 42 and 45 operations, respectively. Thirty-four surgeons (79% response rate) replied to the survey. Fifty-two percent preferred to use the left colon with 81% preferring a substernal placement. The HR QOL survey was performed on 24 patients with a median of 3 years after surgery (ranging from 9 months to 10 years) from the two largest centers and a 56% response rate. Five patients had physical QOL scores above population average and 10 had mental scores above population average. All patients had early satiety, 20 described dysphagia, and 18 regularly took antireflux medication. There was an estimated mean loss of 13.1% body weight (10.6 kg) postoperatively and three patients still relied on a feeding tube for nutrition after an average of 3 years. Colon interposition results in an acceptable long-term QOL. Few centers regularly perform this operation, and centralizing to high-volume centers may lead to better outcomes.

Worldwide Esophageal Cancer Collaboration: clinical staging data

To address uncertainty of whether clinical stage groupings (cTNM) for esophageal cancer share prognostic implications with pathologic groupings after esophagectomy alone (pTNM), we report data-simple descriptions of patient characteristics, cancer categories, and non-risk-adjusted survival-for clinically staged patients from the Worldwide Esophageal Cancer Collaboration (WECC). Thirty-three institutions from six continents submitted data using variables with standard definitions: demographics, comorbidities, clinical cancer categories, and all-cause mortality from first management decision. Of 22,123 clinically staged patients, 8,156 had squamous cell carcinoma, 13,814 adenocarcinoma, 116 adenosquamous carcinoma, and 37 undifferentiated carcinoma. Patients were older (62 years) men (80%) with normal body mass index (18.5-25 mg/kg² , 47%), little weight loss (2.4 ± 7.8 kg), 0-1 ECOG performance status (67%), and history of smoking (67%). Cancers were cT1 (12%), cT2 (22%), cT3 (56%), cN0 (44%), cM0 (95%), and cG2-G3 (89%); most involved the distal esophagus (73%). Non-risk-adjusted survival for squamous cell carcinoma was not distinctive for early cT or cN; for adenocarcinoma, it was distinctive for early versus advanced cT and for cN0 versus cN+. Patients with early cancers had worse survival and those with advanced cancers better survival than expected from equivalent pathologic categories based on prior WECC pathologic data. Thus, clinical and pathologic categories do not share prognostic implications. This makes clinically based treatment decisions difficult and pre-treatment prognostication inaccurate. These data will be the basis for the 8th edition cancer staging manuals following risk adjustment for patient characteristics, cancer categories, and treatment characteristics and should direct 9th edition data collection.

Worldwide Esophageal Cancer Collaboration: pathologic staging data

We report data-simple descriptions of patient characteristics, cancer categories, and non-risk-adjusted survival-for patients with pathologically staged cancer of the esophagus and esophagogastric junction after resection or ablation with no preoperative therapy from the Worldwide Esophageal Cancer Collaboration (WECC). Thirty-three institutions from six continents submitted de-identified data using standard definitions: demographics, comorbidities, clinical cancer categories, and all-cause mortality from first management decision. Of 13,300 patients, 5,631 had squamous cell carcinoma, 7,558 adenocarcinoma, 85 adenosquamous carcinoma, and 26 undifferentiated carcinoma. Patients were older (62 years) men (80%) with normal body mass index (51%), little weight loss (1.8 kg), 0-2 ECOG performance status (83%), and a history of smoking (70%). Cancers were pT1 (24%), pT2 (15%), pT3 (50%), pN0 (52%), pM0 (93%), and pG2-G3 (78%); most involved distal esophagus (71%). Non-risk-adjusted survival for both squamous cell carcinoma and adenocarcinoma was monotonic and distinctive across pTNM. Survival was more distinctive for adenocarcinoma than squamous cell carcinoma when pT was ordered by pN. Survival for pTis-1 adenocarcinoma was better than for squamous cell carcinoma, although monotonic and distinctive for both. WECC pathologic staging data is improved over that of the 7th edition, with more patients studied and patient and cancer variables collected. These data will be the basis for the 8th edition cancer staging manuals following risk adjustment for patient, cancer, and treatment characteristics, and should direct 9th edition data collection. However, the role of pure pathologic staging as the principal point of reference for esophageal cancer staging is waning.

Worldwide Esophageal Cancer Collaboration: neoadjuvant pathologic staging data

To address uncertainty of whether pathologic stage groupings after neoadjuvant therapy (ypTNM) for esophageal cancer share prognostic implications with pathologic groupings after esophagectomy alone (pTNM), we report data-simple descriptions of patient characteristics, cancer categories, and non-risk-adjusted survival-for pathologically staged cancers after neoadjuvant therapy from the Worldwide Esophageal Cancer Collaboration (WECC). Thirty-three institutions from six continents submitted data using variables with standard definitions: demographics, comorbidities, clinical cancer categories, and all-cause mortality from first management decision. Of 7,773 pathologically staged neoadjuvant patients, 2,045 had squamous cell carcinoma, 5,686 adenocarcinoma, 31 adenosquamous carcinoma, and 11 undifferentiated carcinoma. Patients were older (61 years) men (83%) with normal (40%) or overweight (35%) body mass index, 0-1 Eastern Cooperative Oncology Group performance status (96%), and a history of smoking (69%). Cancers were ypT0 (20%), ypT1 (13%), ypT2 (18%), ypT3 (44%), ypN0 (55%), ypM0 (94%), and G2-G3 (72%); most involved the distal esophagus (80%). Non-risk-adjusted survival for yp categories was unequally depressed, more for earlier categories than later, compared with equivalent categories from prior WECC data for esophagectomy-alone patients. Thus, survival of patients with ypT0-2N0M0 cancers was intermediate and similar regardless of ypT; survival for ypN+ cancers was poor. Because prognoses for ypTNM and pTNM categories are dissimilar, prognostication should be based on separate ypTNM categories and groupings. These data will be the basis for the 8th edition cancer staging manuals following risk adjustment for patient, cancer, and treatment characteristics and should direct 9th edition data collection.

The effect of augmenting early nutritional energy delivery on quality of life and employment status one year after ICU admission

Augmenting energy delivery during the acute phase of critical illness may reduce mortality and improve functional outcomes. The objective of this sub-study was to evaluate the effect of early augmented enteral nutrition (EN) during critical illness, on outcomes one year later. We performed prospective longitudinal evaluation of study participants, initially enrolled in The Augmented versus Routine approach to Giving Energy Trial (TARGET), a feasibility study that randomised critically ill patients to 1.5 kcal/ml (augmented) or 1.0 kcal/ml (routine) EN administered at the same rate for up to ten days, who were alive at one year. One year after randomisation Short Form-36 version 2 (SF-36v2) and EuroQol-5D-5L quality of life surveys, and employment status were assessed via telephone survey. At one year there were 71 survivors (1.5 kcal/ml 38 versus 1.0 kcal/ml 33; P=0.55). Thirty-nine (55%) patients consented to this follow-up study and completed the surveys (n = 23 and 16, respectively). The SF-36v2 physical and mental component summary scores were below normal population means but were similar in 1.5 kcal/ml and 1.0 kcal/ml groups (P=0.90 and P=0.71). EuroQol-5D-5L data were also comparable between groups (P=0.70). However, at one-year follow-up, more patients who received 1.5 kcal/ml were employed (7 versus 2; P=0.022). The delivery of 1.5 kcal/ml for a maximum of ten days did not affect self-rated quality of life one year later.

Surgical resection strategy and the influence of radicality on outcomes in oesophageal cancer

BACKGROUND

The optimal surgical approach to tumours of the oesophagus and oesophagogastric junction remains controversial. The principal randomized trial comparing transhiatal (THO) and transthoracic (TTO) oesophagectomy showed no survival difference, but suggested that some subgroups of patients may benefit from the more extended lymphadenectomy typically conducted with TTO.

METHODS

This was a cohort study based on two prospectively created databases. Short- and long-term outcomes for patients undergoing THO and TTO were compared. The primary outcome measure was overall survival, with secondary outcomes including time to recurrence and patterns of disease relapse. A Cox proportional hazards model provided hazard ratios (HRs) and 95 per cent confidence intervals (c.i.), with adjustments for age, tumour stage, tumour grade, response to chemotherapy and lymphovascular invasion.

RESULTS

Of 664 included patients (263 THO, 401 TTO), the distributions of age, sex and histological subtype were similar between the groups. In-hospital mortality (1·1 versus 3·2 per cent for THO and TTO respectively; P = 0·110) and in-hospital stay (14 versus 17 days respectively; P < 0·001) favoured THO. In the adjusted model, there was no difference in overall survival (HR 1·07, 95 per cent c.i. 0·84 to 1·36) or time to tumour recurrence (HR 0·99, 0·76 to 1·29) between the two operations. Local tumour recurrence patterns were similar (22·8 versus 24·4 per cent for THO and TTO respectively). No subgroup could be identified of patients who had benefited from more radical surgery on the basis of tumour location or stage.

CONCLUSION

There was no difference in survival or tumour recurrence for TTO and THO.

Cardiac dysfunction and N-terminal pro-B-type natriuretic peptide in exacerbations of chronic obstructive pulmonary disease

Elevated levels of B-type natriuretic peptides among patients with exacerbations of chronic obstructive pulmonary disease (COPD) are associated with higher mortality. The pathophysiology is unclear. To establish if elevated levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP) are due to right or left heart dysfunction, we performed echocardiograms in 18 patients admitted to hospital with COPD. Elevated levels of NT-proBNP were associated with both right and left heart dysfunction and indicate that these patients have biventricular dysfunction rather than isolated right ventricular compromise.

Salmonella enterica serovar Enteritidis phage type 4 outbreak associated with eggs in a large prison, London 2009: an investigation using cohort and case/non-case study methodology

In September 2009, an outbreak of Salmonella enterica serovar Enteritidis affected 327 of 1419 inmates at a London prison. We applied a cohort design using aggregated data from the kitchen about portions of food distributed, aligned this with individual food histories from 124 cases (18 confirmed, 106 probable) and deduced the exposures of those remaining well. Results showed that prisoners eating egg cress rolls were 26 times more likely to be ill [risk ratio 25.7, 95% confidence interval (CI) 15.5-42.8, P<0.001]. In a case/non-case multivariable analysis the adjusted odds ratio for egg cress rolls was 41.1 (95% CI 10.3-249.7, P<0.001). The epidemiological investigation was strengthened by environmental and microbiological investigations. This paper outlines an approach to investigations in large complex settings where aggregate data for exposures may be available, and led to the development of guidelines for the management of future gastrointestinal outbreaks in prison settings.

Hospital activity and cost incurred because of unregistered patients in England: considerations for current and new commissioners

BACKGROUND

Commissioners are responsible for providing health care for defined geographical areas. A lack of comprehensive national and local information on health needs of unregistered populations makes health service planning difficult.

METHODS

A cross-sectional study using Hospital Episode Statistics to quantify the level of inpatient and outpatient activity, and associated cost by patients not registered in primary care in English NHS hospitals. Unregistered patients were defined as those without a valid GP registration, prisoners, military personnel, asylum seekers/immigrants and the homeless.

RESULTS

Unregistered patients accounted for 99 615 inpatient admissions and 370 504 outpatient attendances in 2009/10, at a total cost of £242 m. Mental health accounted for 30% of all inpatient costs. The majority of unregistered patients were male and aged 20-39 years. There were high levels of activity and cost in urban local authorities (LAs) (Birmingham and London) and LAs with links to military services (Salisbury, Richmondshire, Southampton). A high total inpatient cost was attributed to trauma, general medicine and mental health specialties. A high total outpatient cost was attributed to genitourinary medicine and trauma specialties.

CONCLUSIONS

Health care use by unregistered populations is an important consideration for resource allocation and planning health care services at national and local levels.

Comparison of bacterial identification by MALDI-TOF mass spectrometry and conventional diagnostic microbiology methods: agreement, speed and cost implications

Identification of microbial pathogens still relies primarily on culture and phenotypic methods, which is labour-intensive and time-consuming. In this study, identification of bacteria with valid standard identification using BD Phoenix, API panels and other recommended procedures is compared to identification with matrix-assisted laser desorption/ionisation-time of flight (MALDI-TOF) mass spectrometry using the MALDI Biotyper (Bruker Daltonics) in the setting of a routine NHS diagnostic microbiology laboratory. In total, 928 bacterial isolates obtained from blood (n=463), wounds and pus (n=208), respiratory tract (n=100), faeces (n=86) and urines (n=71) were analysed. There were 721 (77.7%) isolates with a MALDI Biotyper score > or =2.0, indicating secure genus and probable species identification; and 149 (16.1%) isolates with a score > or =1.7 and <2.0 indicating probable genus identification. The isolates with scores of > or =2.0 and > or =1.7 comprised 31 and 33 genera and 65 and 67 species, respectively. Overall, 99.4% and 99.1% of organism identifications were in agreement between the MALDI Biotyper and conventional identification at the genus level, and 89.3% and 87.8% at species level when analysing organisms with MALDI Biotyper scores > or =2.0 and > or =1.7, respectively. With many but not all organisms, identification at the genus level is sufficient; however, MALDI Biotyper separation of 208 staphylococci into Staphylococcus aureus and coagulase-negative staphylococci was always correct when scores were > or =1.7. First results were obtained after 5-10 min and analysis of a full 96-well target plate was completed in approximately 90 min. Substantial savings of between pounds 1.79 and pounds 2.56 per isolate, depending on the cost model of acquisition of the MALDI Biotyper system and number of isolates tested, would be realised when all 928 isolates were identified using the MALDI Biotyper and disk-susceptibility testing when compared to the cost for 618 Phoenix ID panels and 158 API panels and disk-susceptibility tests only (i.e., not taking into account costs incurred for identification of the remaining 152 mixed isolates). Microbial identification by MALDI Biotyper offers a rare opportunity for significant cost-neutral or even cost-saving quality improvements in medical diagnostics.

Constituent country inequalities in myocardial infarction incidence and case fatality in men and women in the United Kingdom, 1996-2005

BACKGROUND

Understanding myocardial infarction (MI) incidence and case fatality trends across the four UK constituent countries is of importance following devolution of the government of health-care services.

METHODS

Retrospective cohort study using a primary care database (5.19 million patients) examining trends in incidence of first MI and 30-day case fatality.

RESULTS

From 1996 to 2005, the incidence of MI decreased in all countries, but reductions were greater in England (men, -3.1%; women, -2.8%) and Wales (men, -3.3%; women, -4.6%) than in Scotland (men, -1.9%; women, -0.6%) and Northern Ireland (men no change, women, -0.8%) (average annual percentage change). Greater reductions in England and Wales than Scotland and Northern Ireland meant a widening of north-south difference in MI incidence over the study period. Downward trends in 30-day case fatality were found in each country but less regional variation was evident (England men, -12.0%, women, -11.0%; Wales men, -18.4%, women, -12.6%; Scotland men, -9.5%, women, -9.0%; Northern Ireland men, -8.6%, women, -13.0%).

CONCLUSION

From 1996 to 2005, downward trends in the incidence of first MI and 30-day case fatality were evident in each constituent country. Greater improvements in case fatality, compared with incidence, were found within each country.

Quasi-Gaussian output from dual case I waveguide resonators with mirrors of step-index reflectivity profiles

There are three recognized low-loss configurations for waveguide laser resonators in which the waveguide is either closed at each end by a plane mirror (dual case I design) or one of the plane mirrors is replaced by a curved mirror at some distance from the guide exit. Some time ago, a variant of the latter design was proposed by exploiting the self-imaging properties of multimode waveguides. The resonator was predicted to produce a TEM(00)-like output with very low round-trip loss and excellent mode discrimination even though the curved mirror was placed much nearer to the guide exit (making the resonator more compact) than was conventional for achieving those results. In the present work, we show that the desirable features of the above design can be achieved even in a dual case I configuration by using end mirrors with suitable reflectivity profiles. Since there is no free space region between the waveguide and the mirrors, the resonator will have the additional advantages of being compact and portable. Furthermore, the absence of curved mirrors will also facilitate its realization in semiconductor integrated optics technology.

The multidisciplinary team meeting improves staging accuracy and treatment selection for gastro-esophageal cancer

The object of this article is to assess current staging accuracies for individual modalities and to investigate the influence of the multidisciplinary team (MDT) on clinical staging accuracies and treatment selection for patients with gastro-esophageal cancer. Patients newly diagnosed with gastric or esophageal cancer and who were deemed suitable for surgical resection by the MDT were studied. Patients were staged with a combination of computerized tomography (CT), endoscopic ultrasound (EUS) and laparoscopic ultrasound (LUS). Additionally, the MDT determined an overall clinical stage for each patient after discussion at the MDT meeting. Treatments were selected according to this final clinical stage. Final histopathological staging (pTNM) was available for all patients and was used as the gold standard for determining staging accuracy. Suitability of treatment selection was assessed once final pTNM was available. One hundred and eighteen patients were studied. Endoscopic ultrasound was the most accurate individual staging modality for the loco-regional assessment of esophageal tumors (T stage accuracy 78%, N stage accuracy 70%). Laparoscopic ultrasound was the most accurate modality in T staging of gastric cancers (91%). The MDT stage was more accurate than each individual staging modality for T and N staging for both gastric and esophageal cancers (accuracy range: 88-89%) and was better for the assessment of nodal disease than each individual modality (CT P < 0.001, EUS P < 0.01, LUS P < 0.01). Overall staging accuracy as determined at the MDT meeting was increased and resulted in only 2/118 (2%) patients being under-treated. The MDT significantly improves staging accuracy for gastro-esophageal cancer and ensures that correct management decisions are made for the highest number of individual patients.

Hypothermia improves outcome from traumatic brain injury

Hypothermia for patients with severe traumatic brain injury (TBI) remains controversial despite a strong biological rationale and reasonable evidence from the literature. The "negative" Clifton study seems to have reduced enthusiasm for hypothermia, however the aim of this review is to analyse the evidence from all randomised controlled trials (RCT) and meta-analyses on this topic to determine whether there is adequate support for the view that hypothermia does improve outcome from TBI. The biological rationale for hypothermia is supported by animal and human mechanistic studies of TBI and human clinical studies of brain injury caused by out-of-hospital cardiac arrest. Several small single-centre RCT's have demonstrated that hypothermia leads to both improved survival and improved favourable neurological outcome in TBI. The Clifton study, which was larger and multi-centre, found hypothermia had no major benefits in TBI, although this study can be criticised for several issues of trial methodology (trial design and application of the intervention) and group comparison. Several meta-analyses have given slightly discordant results, but the two most recent meta-analyses agree that hypothermia improves favourable neurological outcome and probably survival. Subsequent to these meta-analyses, a RCT was published which has confirmed that hypothermia is beneficial in a large group of TBI patients. When the published evidence is considered in total, even if hypothermia can't be justified in all TBI patients, if it is applied optimally in the most appropriate patients, hypothermia certainly improves outcome from TBI. If hypothermia is correctly applied (early, long and cool enough) in the optimal group of TBI patients (young with elevated ICP), there seems to be no doubt that hypothermia is effective in improving both survival and favourable neurological outcome from TBI.

Impact of increasing parenteral protein loads on amino acid levels and balance in critically ill anuric patients on continuous renal replacement therapy

OBJECTIVES

We wanted to establish optimum protein and glucose intakes during total parenteral nutrition by using a constant caloric but changing protein intake in critically ill, ventilated, anuric patients on continuous renal replacement therapy and measuring amino acid and glucose losses across the hemofilter.

METHODS

Eleven consecutive, critically ill patients (eight male, age, 43.5 +/- 21.8 y; Acute Physiology and Chronic Health Evaluation II score, 20.5 +/- 7.0; Acute Physiology and Chronic Health Evaluation risk of death: 36.5% +/- 23.0 and 6 +/- 1 impaired organ systems) entered this study. Patients were fed by continuous infusion of a total parenteral mixture consisting of Synthamin (a mixture of essential and non-essential amino acids), 50% dextrose, and intralipid (long-chain triglycerides) to meet caloric requirements as predicted by Schofield's equation corrected by stress factors. The amount of protein infused was varied (1 to 2.5 g. kg(-1). d(-1)) by increments of 0.25 g. kg(-1). d(-1). Patients were stabilized on each feeding regimen for at least 24 h before paired samples of blood and dialysate were taken for amino acid and glucose measurements. Continuous renal replacement therapy was performed by using a blood pump with a blood flow of 100 to 175 mL/min. Dialysate was pumped in and out counter-currently to the blood flow at 2 L/h. A biocompatible polyacrylonitrile hemofilter was used in all cases.

RESULTS

With protein intakes below 2.5 g. kg(-1). d(-1), blood levels of 14% to 57% of the measured amino acids were below the lower limits of the normal range. At 2.5 g. kg(-1). d(-1), all measured amino acids were within the normal range. Amino acid balance became more positive as protein input increased (P = 0.0001). Glucose and amino acid losses were dependent on blood concentration. Overall, 17% (range, 13% to 24%) of infused amino acids and 4% of infused glucose were lost in the dialysate.

CONCLUSIONS

This study of critically ill, ventilated, anuric patients on continuous renal replacement therapy suggested that increases in protein and glucose are required to account for the increased losses across the hemofilter. A protein intake of 2.5 g. kg(-1). d(-1) appeared to optimize nitrogen balance and correct amino acid deficiencies.

Kv channel subunit expression in rat pulmonary arteries

Hypoxic pulmonary vasoconstriction (HPV) is a mechanism whereby capillary perfusion is modulated to match alveolar ventilation by diverting blood flow away from poorly ventilated regions of the lung. K+ channels, sensitive to changes in oxygen tension, are thought to play a pivotal role in initiating contraction of pulmonary arterial smooth muscle cells. However, the specific channel subtypes involved have not yet been identified. Using RT-PCR, we have investigated the expression of delayed rectifying (Kv) channel mRNA in rat main and small pulmonary arteries and, for comparison, the systemic mesenteric artery. We have identified and fully sequenced a rat Kv9.2 cDNA and also demonstrated the presence of Kv1.7 and Kv4.1. The presence and relative distribution of Kv1.2, Kv1.5, Kv2.1, and Kv9 mRNA is consistent with the proposed contribution of these subunits to oxygen sensing by K channels, previously described in pulmonary arteries. Our data addresses the controversy relating to the likely distribution of Kv channels involved in oxygen sensing without necessarily implying that such subunits are directly responsible for this process. The differential expression of other subunits, particularly Kv4, indicates that these too may have a role in HPV, revealing the need for further biophysical evaluation of these channel subtypes.

Identification of the glycosylation sites utilized on the V1a vasopressin receptor and assessment of their role in receptor signalling and expression

Most of the large family of G-protein-coupled receptors (GPCRs) possess putative N-glycosylation sites within their N-termini. However, for the vast majority of GPCRs, it has not been determined which, if any, of the consensus glycosylation sites are actually utilized or what the functional ramifications are of modification by oligosaccharide. The occurrence and function of glycosylation of the V(1a) vasopressin receptor (V(1a)R) has been investigated in this study. Using a combination of translation systems that are either glycosylation-competent or do not support glycosylation, we established that of the four putative N-glycosylation sites at Asn(14), Asn(27), Asn(198) and Asn(333) only the first three sites are actually modified by carbohydrate. This was confirmed by disruption of consensus sites by site-directed mutagenesis, individually and in combination. The V(1a)R is not O-glycosylated. The functionality of a series of glycosylation-defective V(1a)R constructs was characterized after expression in HEK 293T cells. It was found that carbohydrate moieties are not required for the receptor to bind any of the four classes of ligand available, or for intracellular signalling. The glycosylation status of the V(1a)R did, however, regulate the level of total receptor expression and also the abundance of receptor at the cell surface. Furthermore, the nature of this regulation (increased or decreased expression) was dictated by the locus of the oligosaccharide modification. Modification of any one of the consensus sites alone, however, was sufficient for wild-type expression, indicating a redundancy within the glycosylation sites. A role for the carbohydrate in the correct folding or stabilization of the V(1a)R is indicated. Glycosylation is not required, however, for efficient trafficking of the receptor to the cell surface. This study establishes the functional importance of N-glycosylation of the V(1a)R.

Evidence-based medicine in intensive care

The life-threatening nature of critical illness, requiring simultaneous, multiple interventions, makes it difficult, if not impossible, to study the effects of any one treatment. It is often not possible to conduct trials in critically ill patients, as they can not give informed consent. Some high quality, prospective studies have influenced clinical practice in intensive care, but others with lower grades of evidence have led to some controversy. In intensive care, clinical practice is still influenced by a combination of theory, experience and evidence.

High lactate predicts the failure of intraaortic balloon pumping after cardiac surgery

BACKGROUND

Despite the use of intraaortic balloon pump (IABP) support in complex cardiac surgical patients, morbidity and mortality rates are high. More advanced mechanical cardiovascular support should be considered in those patients who are highly likely to die despite IABP support. We sought to identify early, readily available prognostic markers for patients receiving IABP support.

METHODS

A retrospective analysis was performed on 39 patients requiring IABP support following cardiac surgery for more than 2 years. The accuracy and predictive ability of multiple potential markers of mortality were statistically assessed.

RESULTS

Sixty-seven percent of the patients were successfully weaned from IABP support and 46% survived to hospital discharge. Serious complications occurred in 13% of patients. Serum lactate more than 10 mmol/L in the first 8 hours of IABP support predicted a 100% mortality. Base deficit more than 10 mmol/L, mean arterial pressure less than 60 mm Hg, urine output less than 30 mls/h for 2 hours, and dose of epinephrine or norepinephrine more than 10 microg/min were other highly predictive prognostic markers.

CONCLUSIONS

Morbidity and mortality rates remain high despite IABP support following cardiac surgery. Mortality can be predicted by the presence of elevated serum lactate, elevated base deficit, hypotension, oliguria and large vasopressor doses, any of which should prompt appropriate consideration as to other mechanical cardiovascular support.

[3H]-Methyllycaconitine: a high affinity radioligand that labels invertebrate nicotinic acetylcholine receptors

Nicotinic acetylcholine receptors (nAChR) of insect and other invertebrates are heterogeneous and new tools are needed to dissect their multiplicity. [(3)H]-Methyllycaconitine ([(3)H]-MLA) is a novel radioligand which is a potent antagonist at vertebrate alpha7-type nAChR. Putative invertebrate nAChR of the aphid Myzus persicae, the moths Heliothis virescens and Manduca sexta, the fly Lucilia sericata, and the squid Loligo vulgaris were investigated in radioligand binding studies with [(3)H]-MLA. Saturable binding was consistent with a single class of high affinity binding sites for each of these invertebrates, characterised by a dissociation constant, K(d), of approximately 1 nM and maximal binding capacities, B(max), between 749 and 1689 fmol/mg protein for the insects and 14,111 fmol/mg protein for squid. [(3)H]-MLA binding to M. persicae membranes was characterised in more detail. Kinetic analysis demonstrated rapid association in a biphasic manner and slow, monophasic dissociation. Displacement studies demonstrate the nicotinic character of [(3)H]-MLA binding sites. Data for all nicotinic ligands, except MLA itself, are consistent with displacement from a high and a low affinity site, indicating that displacement is occurring from two or more classes of nicotinic binding site that are not distinguished by MLA itself. Autoradiographic analysis of the distribution of [(3)H]-MLA binding sites in Manduca sexta shows discrete labelling of neuropil areas of the optic and antennal lobes.

A microprocessor based instrument for the spectral analysis of the EEG in anaesthesia

An instrument for monitoring the frequency components contained in the electroencephalogram is described. The technique uses the fast Fourier transform which is implemented in a microprocessor controlled 'black box'. The control and display of the data are organised by a conventional microcomputer. The system is designed for use by practising anaesthetists in a district general hospital environment and is, therefore, inexpensive and simple to operate. The operation of the equipment is described and some limited results from early clinical trials are presented.

Using root cause analysis to address patient satisfaction and other improvement opportunities

BACKGROUND

Despite the considerable attention that health care organizations are devoting to the measurement of patient satisfaction, there is often confusion about how to systematically use these data to improve an organization's performance. A model to use in applying traditional quality improvement methods and tools to patient satisfaction problems includes five primary steps: (1) identifying opportunities, (2) prioritizing opportunities, (3) conducting root cause analysis, (4) designing and testing potential solutions, and (5) implementing the proposed solution.

PATIENT SATISFACTION SURVEYS

A satisfaction survey serves best as a high-level screening device, not as a tool to provide highly detailed information about the root causes of patient dissatisfaction. The primary purpose of the survey in the model is to identify improvement opportunities and areas of significant improvement or deterioration. Secondary tools such as brief patient interviews or focus groups may better serve to probe intensively into the problem areas identified by the survey. These tools allow for a direct dialog with the patient to uncover root causes of dissatisfaction and establish potential solutions.

DISCUSSION

Although the primary focus of this model has been patient satisfaction issues, the basic steps could easily be applied to virtually any improvement opportunity. Improvement teams should commit to a schedule of 90-minute weekly meetings for 7 weeks. The model, a simple translation of traditional improvement methods and tools to address the unique issues facing patient satisfaction improvement teams, can save improvement teams considerable time, resources, and frustration as they design and launch initiatives to improve patient satisfaction.

Endothelial cells freshly isolated from resistance-sized pulmonary arteries possess a unique K(+) current profile

We have, for the first time, developed a reliable method for freshly isolating viable endothelial cells from resistance-sized rat pulmonary arteries. The endothelial origin of these cells was confirmed using indirect immunofluorescence, utilizing fluorescently labeled low-density lipoprotein. Biophysical and pharmacological patch-clamp experiments conducted under quasiphysiological cationic gradients revealed that these cells had a mean resting membrane potential of approximately -38 mV and displayed a delayed-rectifying K(+) current. Immunohistochemical staining of rat lung cross-sections revealed an abundance of K(V)1.5 channel protein in pulmonary endothelium. This is the first report of a delayed-rectifying K(+) current in endothelial cells of resistance-sized pulmonary arteries. Since changes in membrane potential associated with K(+) channel activity affect release of vasoactive substances from endothelial cells, this finding has important implications for understanding the mechanisms underlying control of pulmonary vascular tone.

An autoradiographic study of the distribution of binding sites for the novel alpha7-selective nicotinic radioligand [3H]-methyllycaconitine in the mouse brain

[3H]-Methyllycaconitine ([3H]-MLA) is a new radioligand with selectivity for alpha7-type neuronal nicotinic acetylcholine receptors (nAChRs). In our previous study [Davies, A.R.L., Hardick, D.J., Blagbrough, I.S., Potter, B.V.L., Wolstenholme, A.J. & Wonnacott, S. (1999) Neuropharmacology, 38, 679-690], this radioligand labelled a single class of site in rat brain membranes; its pharmacology and distribution in crudely dissected brain regions closely paralleled that of the well-established alpha7-ligand [125I]-alpha-bungarotoxin. However, a small population of [3H]-MLA binding sites was apparently insensitive to alpha-bungarotoxin. Here we have extended the study to mouse brain, using autoradiography to examine the distribution of [3H]-MLA and [125I]-alpha-bungarotoxin binding sites. [3H]-MLA labelled a single class of site in mouse brain membranes with a KD of 2.2 nM and a Bmax of 45.6 fmol/mg protein. Specific binding, defined by unlabelled MLA (Ki = 0.69 nM), was completely inhibited by (-)-nicotine (Ki = 1.62 microM), whereas alpha-bungarotoxin inhibited only 85% of specific binding (Ki = 3.5 nM). The distributions of [125I]-alpha-bungarotoxin and [3H]-MLA binding sites were compared by autoradiography, and binding was quantitated in 72 brain regions. Binding of both radioligands was highly correlated, with highest densities in the dorsal tegmental nucleus of the pons, colliculi and hippocampus. Serial sections labelled with [3H]-MLA in the absence or presence of unlabelled MLA or alpha-bungarotoxin provided no evidence for any alpha-bungarotoxin-resistant binding. The results are discussed in terms of binding sites that are inaccessible to alpha-bungarotoxin in membrane preparations. This study demonstrates the utility of [3H]-MLA for characterization of alpha7-type nicotinic receptors in mammalian brain, and suggests that it labels a population identical to that defined by [125I]-alpha-bungarotoxin.

Understanding patient willingness to recommend and return: a strategy for prioritizing improvement opportunities

BACKGROUND

Beginning in April 1995, an ongoing, comprehensive measurement system has been developed and refined at BJC Health System, a regional integrated delivery and financing system serving the St Louis metropolitan area, mid-Missouri, and Southern Illinois, to assess patient satisfaction with inpatient treatment, outpatient treatment, outpatient surgery, and emergency care. This system has provided the mechanism for identifying opportunities, setting priorities, and monitoring the impact of improvement initiatives.

METHODS

Satisfaction with key components of the care process among 23,361 patients (7,083 inpatients, 8,885 patients undergoing outpatient tests/procedures, 5,356 patients undergoing outpatient surgery, and 2,037 patients receiving emergency care) at 15 BJC Health System facilities was assessed through weekly surveys administered in April 1995 through December 1996.

RESULTS

Structural equation models were developed to identify the key predictors of patient advocation-willingness to return for or recommend care. Across all venues of care the compassion provided to patients had the strongest relationship to patient advocation. Within each venue of care, however, a slightly different set of secondary factors emerged. The resulting models provided important information to help prioritize competing improvement opportunities in BJC Health System. In one hospital, a general medicine unit working for several years with little success to improve its patient satisfaction decided to focus on two primary factors predicting patient advocation: nursing care delivery and compassionate care. Root cause analysis was used to determine why two items-staff willingness to help with questions/concerns and clear explanation about tests and procedures-were rated low. On the basis of feedback from phone interviews with discharged patients, the care delivery process was changed to encourage patients to ask questions. Across the next two quarters, this unit experienced significant improvements in both targeted items.

DISCUSSION

The significance of compassionate care and care delivery again speaks not only to the importance of the technical quality of clinical care but also to the customer-focused way in which this care was provided. After the primary predictors of patient advocation were identified, management was able to strategically focus improvement initiatives to maximize their impact. Across the organization, improvement teams scanned their data to find key factors where performance was lacking. Once these key opportunities were identified, the teams developed potential solutions and launched initiatives to improve their performance.

SUMMARY AND CONCLUSIONS

Results suggest that some core issues are of extreme importance to patients regardless of whether they are receiving care in an inpatient, outpatient, or emergency setting. The compassion with which care is provided appears to be the most important factor in influencing patient intentions to recommend/return, regardless of the setting in which care is provided.

Characterisation of the binding of [3H]methyllycaconitine: a new radioligand for labelling alpha 7-type neuronal nicotinic acetylcholine receptors

Methyllycaconitine (MLA), a norditerpenoid alkaloid isolated from Delphinium seeds, is one of the most potent non-proteinacious ligands that is selective for alpha bungarotoxin-sensitive neuronal nicotinic acetylcholine receptors (nAChR). [3H]MLA bound to rat brain membranes with high affinity (Kd = 1.86 +/- 0.31 nM) with a good ratio of specific to non-specific binding. The binding of [3H]MLA was characterised by rapid association (t 1/2 = 2.3 min) and dissociation (t 1/2 = 12.6 min) kinetics. The radioligand binding displayed nicotinic pharmacology, consistent with an interaction with alpha bungarotoxin-sensitive nAChR. The snake alpha-toxins, alpha bungarotoxin and alpha cobratoxin, displaced [3H]MLA with high affinity (Ki = 1.8 +/- 0.5 and 5.5 +/- 0.9 nM, respectively), whereas nicotine was less potent (Ki = 6.1 +/- 1.1 microM). The distribution of [3H]MLA binding sites in crudely dissected rat brain regions was identical to that of [125I] alpha bungarotoxin binding sites, with a high binding site density in hippocampus and hypothalamus, but low density in striatum and cerebellum. [3H]MLA also labelled a sub-population of binding sites which are not sensitive to the snake alpha toxins, but which did not differ significantly from the major population with respect to their other pharmacological properties or regional distribution. [3H]MLA, therefore, is a novel radiolabel for characterising alpha 7-type nAChR. A good signal to noise ratio and rapid binding kinetics provide advantages over the use of radiolabelled alpha bungarotoxin for rapid and accurate equilibrium binding assays.

Comparison of Talbot and 1-to- N-way phase-locked array resonators

Phased-array resonators provide an important basis for achieving high output powers from arrays of low-power elements. We have recently proposed a novel form of 1-to-N-way phased-array resonator based on the beam splitting and regeneration characteristics of rectangular sectioned multimode waveguides. We compare its performance with that of the widely used, yet problematic, Talbot resonator. Our design is found to have significant advantages over the Talbot resonator in terms of improved modal stability, unique photon-mixing characteristics, and near- and far-field outputs of quasi-Gaussian form.