Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

BACKGROUND

Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks.

METHODS

The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned.

RESULTS

A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31).

CONCLUSION

Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov).

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.

Lack of anti-TNF drugs levels in fistula tissue - a reason for nonresponse in Crohn's perianal fistulating disease?

INTRODUCTION

Anti-TNF therapy is recommended as treatment for patients with Crohn´s perianal fistulas. However, a significant proportion of patients have a sub-optimal response to anti-TNF therapy. Higher serum levels of anti-TNF agents have been associated with improved outcomes in perianal Crohn's disease. Currently, it is unknown whether anti-TNF agent levels can be detected in tissue from fistula tracts themselves and whether this is associated with response.

AIMS AND METHODS

We undertook a pilot study to measure fistula tissue levels of anti-TNF medication (infliximab and adalimumab). We used a previously validated targeted proteomic technique, employing ultraperformance liquid chromatography-mass spectrometry, to detect/quantify anti-TNF drugs. Biopsies were obtained from fistula tracts of patients with Crohn's disease on maintenance treatment; with idiopathic (cryptoglandular) fistula tissues used as negative controls as well as positive controls (by spiking the latter tissues with anti-TNF drugs).

RESULTS

Tissue was sampled from the fistula tracts of seven patients with Crohn's perianal disease (five patients were on adalimumab and two patients were on infliximab). The anti-TNF drugs, infliximab and adalimumab, were not detected in fistula samples from any of the Crohn's patients despite detection in 'spiked' positive control samples.

CONCLUSION

Absence of detection of the anti-TNF drugs in fistula tissue raises the question on the role of tissue penetrance of anti-TNF drugs in response to therapy. Further work is required in a larger number of patients to validate the findings observed and investigate if any correlation exists between tissue and serum levels of anti-TNF and clinical outcome.

SUMMARY

Predicting response in Crohn's fistula patients on biologic therapy is difficult with no reliable biomarkers. This pilot study uses targeted proteomics to investigate the potential role of tissue drug levels in acting as a biomarker of treatment response.

Megarectum: systematic histopathological evaluation of 35 patients and new common pathways in chronic rectal dilatation

AIMS

Megarectum is well described in the surgical literature but few contemporary pathological studies have been undertaken. There is uncertainty whether 'idiopathic' megarectum is a primary neuromuscular disorder or whether chronic dilatation leads to previously reported and unreported pathological changes. We sought to answer this question.

METHODS

Systematic histopathological evaluation (in accord with international guidance) of 35 consecutive patients undergoing rectal excision surgery for megarectum (primary: n=24) or megarectum following surgical correction of anorectal malformation (secondary: n=11) in a UK university hospital with adult/paediatric surgical and gastrointestinal neuropathology expertise.

RESULTS

We confirmed some previously reported observations, notably hypertrophy of the muscularis propria (27 of 35, 77.1% of patients) and extensive fibrosis (30 of 35, 85.7% of patients). We also observed unique and previously unreported features including elastosis (19 of 33, 57.6%) and the presence of polyglucosan bodies (15 of 32, 46.9% of patients). In contrast to previous literature, few patients had any strong evidence of specific forms of visceral neuropathy (5 of 35, including 3 plexus duplications) or myopathy (6 of 35, including 3 muscle duplications). All major pathological findings were common to both primary and secondary forms of the disease, implying that these may be a response to chronic rectal distension rather than of primary aetiology.

CONCLUSIONS

In the largest case series reported to date, we challenge the current perception of idiopathic megarectum as a primary neuromuscular disease and propose a cellular pathway model for the features present. The severe morphological changes account for some of the irreversibility of the condition and reinforce the need to prevent ongoing rectal distension when first identified.

Systematic evaluation of cough-anorectal pressure responses in health and in fecal incontinence: A high-resolution anorectal manometry study

BACKGROUND

Anorectal manometry is the most commonly performed test of anorectal function. The cough-anorectal response is frequently assessed as part of a routine manometric investigation but has not previously been the subject of detailed analysis. This study systematically examined anorectal pressure responses to cough in health and evaluated the impact of parity and symptoms of fecal incontinence (FI) on measurements.

METHODS

High-resolution anorectal manometry (HR-ARM) traces from nulliparous (n = 25) and parous (n = 25) healthy volunteers (HV: aged 41, range 18-64), and 57 parous patients with FI (age 47, range 28-72) were retrospectively reviewed. Cough-anorectal pressure responses were analyzed between groups by qualitative and quantitative approaches.

KEY RESULTS

In health, traditional anal pressure measurements ("rest" and "squeeze") were similar between nulliparous and parous women. In contrast, incremental anal-rectal pressure difference during cough significantly differed: nulliparous 42 mm Hg (95% CI: 21-64) vs. parous 6 mm Hg (-14-25), P < 0.036). This measure also differed significantly between nulliparous HVs and patients with FI (-2 mm Hg (95% CI: -15-12), P < 0.001), but not between parous HVs and FI. Qualitatively, a color-contour trace resembling a "spear" in the upper anal canal was observed uniquely in FI. Of 25 patients with normal anal function by traditional measures, cough parameters were abnormal in 52%.

CONCLUSIONS AND INFERENCES

Novel HR-ARM measures during coughing revealed differences in anal function between nulliparous and parous HV, and patients with FI, which were not detected by traditional measures. Cough-anorectal measurements may improve manometric yield, though clinical utility would require assessment by longitudinal studies.

DyNeuMo Mk-2: An Investigational Circadian-Locked Neuromodulator with Responsive Stimulation for Applied Chronobiology

Deep brain stimulation (DBS) for Parkinson's disease, essential tremor and epilepsy is an established palliative treatment. DBS uses electrical neuromodulation to suppress symptoms. Most current systems provide a continuous pattern of fixed stimulation, with clinical follow-ups to refine settings constrained to normal office hours. An issue with this management strategy is that the impact of stimulation on circadian, i.e. sleep-wake, rhythms is not fully considered; either in the device design or in the clinical follow-up. Since devices can be implanted in brain targets that couple into the reticular activating network, impact on wakefulness and sleep can be significant. This issue will likely grow as new targets are explored, with the potential to create entraining signals that are uncoupled from environmental influences. To address this issue, we have designed a new brain-machine-interface for DBS that combines a slow-adaptive circadian-based stimulation pattern with a fast-acting pathway for responsive stimulation, demonstrated here for seizure management. In preparation for first-in-human research trials to explore the utility of multi-timescale automated adaptive algorithms, design and prototyping was carried out in line with ISO risk management standards, ensuring patient safety. The ultimate aim is to account for chronobiology within the algorithms embedded in brain-machine-interfaces and in neuromodulation technology more broadly.

Prolonged operative time increases risk of blood loss and transfusion requirements in revision hip surgery

INTRODUCTION

Revision hip surgery is well documented to have a high association with substantial blood loss and the associated need for a blood transfusion. This exposes the patient to increased risk of transfusion reaction and blood borne infection. There are many strategies to minimize allogeneic transfusion rates in revision surgery such as pre-operative autologous donation, peri-operative tranexamic acid, thrombin sealants, normovolaemic haemodilution, intra-operative blood salvage and the use of post-operative autologous drains.

PATIENTS AND METHODS

We prospectively looked at 177 consecutive cases performed at one centre by a single surgical and anaesthetic team to identify which patient and operative factors were most significant in minimizing the requirement for an allogeneic blood transfusion.

RESULTS

Our results identified the duration of surgery as being the only significant variable affecting the level of blood loss. We noted a 3% increase in the probability of massive blood loss (> 2000 mls) for every minute of increased surgical time in our series.

CONCLUSIONS

We conclude that measures to minimize the duration of surgery would be beneficial in reducing blood loss and the risks of requiring blood transfusions in revision hip surgery.

Randomised, double-blind, placebo controlled multi-centre study to assess the efficacy, tolerability and safety of Enterosgel® in the treatment of irritable bowel syndrome with diarrhoea (IBS-D) in adults

BACKGROUND

Irritable bowel syndrome (IBS) with diarrhoea (IBS-D) is a common and chronic condition that can significantly impair quality of life. The emergence of new drugs for IBS-D has been slow and there is a need for new treatments, including drug-free treatments, which are easy to use and suitable for different patient groups. Currently available drug-free treatments include Enterosgel®, an intestinal adsorbent approved for use in IBS-D and acute diarrhoea and available over-the-counter in the UK and 30 countries worldwide. The aim of this randomised, double-blind, placebo-controlled, multi-centre study is to test the efficacy and safety of Enterosgel® compared to placebo in symptomatic treatment in IBS-D.

METHODS/DESIGN

We will recruit 430 participants with IBS-D from approximately 30 primary and secondary care sites in England. Participants meeting the required abdominal pain and stool consistency criteria over a 2-week screening period will be randomly allocated to receive blinded treatment (Enterosgel® or placebo) for 8 weeks. This will be followed by an 8-week open-label treatment phase with Enterosgel®. Participants will be allowed to adjust their daily dosage during both phases based on their symptoms. Participants will then return to standard care and those who responded to treatment will receive a follow-up call 8 weeks later. Co-medication with loperamide will be permitted and use recorded. The primary outcome measure is the percentage of participants defined as responders for abdominal pain and stool consistency during at least 4 weeks in the 8-week blinded phase. Secondary outcome measures include stool frequency, stool consistency, abdominal pain, bloating, urgency, adequate relief, questionnaire scores and rescue medication use. Exploratory outcomes will be assessed in subsets of participants including qualitative and quantitative data on faecal microorganisms and biomarkers and gut-related measurements from magnetic resonance imaging data.

DISCUSSION

This is the first large scale randomised controlled trial investigating Enterosgel® in IBS-D. A study design with blinded phase followed by an open-label phase was chosen to encourage participation and study completion. Demonstrating that Enterosgel® is effective and safe in IBS-D could encourage adoption by patients and healthcare professionals and foster future clinical trials assessing its use in related conditions.

TRIAL REGISTRATION

ISRCTN17149988. Prospectively registered on 14 November 2017.

Evaluation of a Novel Field-placement Algorithm for Locoregional Breast Cancer Radiotherapy Including the Internal Mammary Chain

AIMS

Irradiation of the internal mammary chain (IMC) is increasing following recently published data, but the need for formal delineation of lymph node volumes is slowing implementation in some healthcare settings. A field-placement algorithm for irradiating locoregional lymph nodes including the IMC could reduce the resource impact of introducing irradiation of the IMC. This study describes the development and evaluation of such an algorithm.

MATERIALS AND METHODS

An algorithm was developed in which six points representing lymph node clinical target volume borders (based on European Society for Radiotherapy and Oncology consensus nodal contouring guidelines) were placed on computed tomography-defined anatomical landmarks and used to place tangential and nodal fields. Single-centre testing in 20 cases assessed the success of the algorithm in covering planning target volumes (PTVs) and adequately sparing organs at risk. Plans derived using the points algorithm were also compared with plans generated following formal delineation of nodal PTVs, using the Wilcoxon signed rank test. Timing data for point placement were collected. Multicentre testing using the same methods was then carried out to establish whether the technique was transferable to other centres.

RESULTS

Single-centre testing showed that 95% of cases met the nodal PTV coverage dose constraints (binomial probability confidence interval 75.1-99.9%) with no statistically significant reduction in mean heart dose or ipsilateral lung V17Gy associated with formal nodal delineation. In multicentre testing, 69% of cases met nodal PTV dose constraints and there was a statistically significant difference in IMC PTV coverage using the points algorithm when compared with formally delineated nodal volumes (P < 0.01). However, there was no difference in axillary level 1-4 PTV coverage (P = 0.11) with all cases meeting target volume constraints.

CONCLUSIONS

The optimal strategy for breast and locoregional lymph node radiotherapy is target volume delineation. However, use of this novel points-based field-placement algorithm results in dosimetrically acceptable plans without the need for formal lymph node contouring in a single-centre setting and for the breast and level 1-4 axilla in a multicentre setting. Further quality assurance measures are needed to enable implementation of the algorithm for irradiation of the IMC in a multicentre setting.

Feasibility of using a novel non-invasive ambulatory tibial nerve stimulation device for the home-based treatment of overactive bladder symptoms

Background

To evaluate safety, acceptability and pilot efficacy of transcutaneous low-frequency tibial nerve stimulation (TNS) using a novel device as home-based neuromodulation.

Methods

In this single-centre pilot study, 48 patients with overactive bladder (OAB) (24 with neurogenic and 24 with idiopathic OAB) were randomized to use a self-applicating ambulatory skin-adhering device stimulating transcutaneously the tibial nerve at 1 Hz for 30 minutes, either once daily or once weekly, for 12 weeks. Changes in OAB symptoms and QoL were measured at baseline, weeks 4, 8, and 12 using validated scoring instruments (ICIQ-OAB and ICIQ-LUTSqol), 3-day bladder diary and a Global Response Assessment (GRA) at week 12.

Results

Thirty-four patients completed the study (idiopathic n=15, neurogenic n=19). No significant adverse effects were noted. Patients found the device acceptable. Eighteen patients (53%) reported a moderate or marked improvement in symptoms from the GRA. Between baseline and week-12, ICIQ-OAB part A sub-scores improved from mean (SD) 9.3 (2.5) to 7.5 (3.1), and from 9.1 (1.9) to 5.9 (1.7) in the daily and the weekly arms, respectively. ICIQ-LUTSqol part A sub-scores improved from mean (SD) 51 (12.8) to 44.2 (13.1) and 44.9 (9.0) to 35.9 (8.8) in the daily and the weekly arms, respectively. Bladder diary mean 24-hour frequency episodes improved from 11.5 to 8.8 at week 12 for both arms.

Conclusions

This novel ambulatory transcutaneous TNS (TTNS) device is safe and acceptable for use in patients reporting OAB symptoms as a form of home-based neuromodulation. A larger study however is required to confirm clinical efficacy.

When all seems lost: management of refractory constipation-Surgery, rectal irrigation, percutaneous endoscopic colostomy, and more

While the pharmacological armamentarium for chronic constipation has expanded over the past few years, a substantial proportion of constipated patients do not respond to these medications. This review summarizes the pharmacological and behavioral options for managing constipation and details the management of refractory constipation. Refractory constipation is defined as an inadequate improvement in constipation symptoms evaluated with an objective scale despite adequate therapy (ie, pharmacological and/or behavioral) that is based on the underlying pathophysiology of constipation. Minimally invasive (ie, rectal irrigation and percutaneous endoscopic colostomy) and surgical therapies are used to manage refractory constipation. This review appraises these options, and in particular, percutaneous endoscopic colostomy, which as detailed by an article in this issue, is a less invasive option for managing refractory constipation than surgery. While these options benefit some patients, the evidence of the risk: benefit profile for these therapies is limited.

Low-volume versus high-volume initiated trans-anal irrigation therapy in adults with chronic constipation: study protocol for a randomised controlled trial

BACKGROUND

Constipation is common in adults and up to 20% of the population report this symptom. Chronic constipation (CC), usually defined as more than 6 months of symptoms, is less common but results in 0.5 million UK GP consultations per annum. The effect of symptoms on measured quality of life (QOL) is significant, and CC consumes significant health care resources. In the UK, it is estimated that 10% of district nursing time is spent on constipation. Trans-anal irrigation therapy has become a widely used treatment despite a lack of robust efficacy data to support its use. The long-term outcome of treatment is also unclear. A randomised comparison of two different methods of irrigation (high- and low-volume) will provide valuable evidence of superiority of one system over the other, as well as providing efficacy data for the treatment as a whole.

METHODS

Participants will be recruited based on predetermined eligibility criteria. Following informed consent, they will be randomised to either high-volume (HV) or low-volume (LV) irrigation and undergo standardised radiological and physiological investigations. Following training, they will commence home irrigation with the allocated device. Data will be collected at 1, 3, 6 and 12 months according to a standardised outcomes framework. The primary outcome is PAC-QOL, measured at 3 months. The study is powered to detect a 10% difference in outcome between systems at 3 months; this means that 300 patients will need to be recruited.

DISCUSSION

This study will be the first randomised comparison of two different methods of trans-anal irrigation. It will also be the largest prospective study of CC patients treated with irrigation. It will provide evidence for the effectiveness of irrigation in the treatment of CC, as well as the comparative effectiveness of the two methods. This will enable more cost-effective and evidence-based use of irrigation. Also, the results will be combined with the other studies in the CapaCiTY programme to generate an evidence-based treatment algorithm for CC in adults.

TRIAL REGISTRATION

ISRCTN, identifier: ISRCTN11093872 . Registered on 11 November 2015. Trial not retrospectively registered. Protocol version 3 (22 January 2016).

Functional Anorectal Disorders

This report defines criteria and reviews the epidemiology, pathophysiology, and management of common anorectal disorders: fecal incontinence (FI), functional anorectal pain and functional defecation disorders. FI is defined as the recurrent uncontrolled passage of fecal material for at least 3 months. The clinical features of FI are useful for guiding diagnostic testing and therapy. Anorectal manometry and imaging are useful for evaluating anal and pelvic floor structure and function. Education, antidiarrheals and biofeedback therapy are the mainstay of management; surgery may be useful in refractory cases. Functional anorectal pain syndromes are defined by clinical features and categorized into three subtypes. In proctalgia fugax, the pain is typically fleeting and lasts for seconds to minutes. In levator ani syndrome (LAS) and unspecified anorectal pain the pain lasts more than 30 minutes, but in LAS there is puborectalis tenderness. Functional defecation disorders are defined by >2 symptoms of chronic constipation or irritable bowel syndrome with constipation, and with >2 features of impaired evacuation i.e., abnormal evacuation pattern on manometry, abnormal balloon expulsion test or impaired rectal evacuation by imaging. It includes two subtypes; dyssynergic defecation and inadequate defecatory propulsion. Pelvic floor biofeedback therapy is effective for treating LAS and defecatory disorders.

Functional Anorectal Disorders

This report defines criteria and reviews the epidemiology, pathophysiology, and management of common anorectal disorders: fecal incontinence (FI), functional anorectal pain and functional defecation disorders. FI is defined as the recurrent uncontrolled passage of fecal material for at least 3 months. The clinical features of FI are useful for guiding diagnostic testing and therapy. Anorectal manometry and imaging are useful for evaluating anal and pelvic floor structure and function. Education, antidiarrheals and biofeedback therapy are the mainstay of management; surgery may be useful in refractory cases. Functional anorectal pain syndromes are defined by clinical features and categorized into three subtypes. In proctalgia fugax, the pain is typically fleeting and lasts for seconds to minutes. In levator ani syndrome (LAS) and unspecified anorectal pain the pain lasts more than 30 minutes, but in LAS there is puborectalis tenderness. Functional defecation disorders are defined by >2 symptoms of chronic constipation or irritable bowel syndrome with constipation, and with >2 features of impaired evacuation i.e., abnormal evacuation pattern on manometry, abnormal balloon expulsion test or impaired rectal evacuation by imaging. It includes two subtypes; dyssynergic defecation and inadequate defecatory propulsion. Pelvic floor biofeedback therapy is effective for treating LAS and defecatory disorders.

Comparative quantitative assessment of global small bowel motility using magnetic resonance imaging in chronic intestinal pseudo-obstruction and healthy controls

BACKGROUND

Chronic intestinal pseudo-obstruction (CIPO) is characterized by dilatation of the bowel lumen and abnormal motility. In this study, we aimed to quantify small bowel dysmotility in CIPO using a validated pan-intestinal motility assessment technique based on motion capture magnetic resonance imaging (MRI) compared to normal controls. In addition, we explored if motility responses of CIPO patients to neostigmine challenge differed from healthy volunteers.

METHODS

Twenty healthy volunteers (mean age 28, range 22-48) and 11 CIPO patients (mean age 47, range 19-90) underwent MRI enterography to capture global small bowel motility. Eleven controls and seven CIPO patients further underwent a randomized placebo-controlled crossover study of either intravenous neostigmine (0.5 mg) or saline with motility MRI repeated at a mean of 3 weeks. Motility was quantified in regions of interest placed to encompass the whole small bowel volume using a validated, postprocessing technique to give a global motility index in arbitrary units (AU). Baseline and stimulated motility was compared using Wilcoxon rank-sum paired T-tests.

KEY RESULTS

Baseline global small bowel motility was significantly lower in CIPO patients compared to controls (mean 0.25 AU vs 0.35 AU, p < 0.001). Motility in both groups increased significantly after neostigmine (0.06 AU increase, p = 0.016 in CIPO and 0.06 AU increase, p = 0.002 in controls). Three patients with scleroderma had a reduced response to neostigmine.

CONCLUSIONS & INFERENCES

Global small bowel motility in CIPO patients is significantly lower than controls and response to the pro-kinetic agent neostigmine may differ according to disease phenotype. Software-quantified bowel motility using cine MRI has potential as a future tool to investigate enteric dysmotility.

SINGLE CENTRE RANDOMISED PILOT STUDY OF TWO REGIMENS (30 MINS DAILY OR 30 MINS WEEKLY FOR 12 WEEKS) OF TRANSCUTANEOUS TIBIAL NERVE STIMULATION USING A NOVEL DEVICE FOR TREATING MULTIPLE SCLEROSIS-RELATED OVERACTIVE BLADDER SYMPTOMS

Introduction

Percutaneous tibial nerve stimulation (PTNS) is effective for managing multiple sclerosis (MS)-related overactive bladder (OAB) symptoms. However the need for weekly clinic visits restricts its use. The purpose of this study was to evaluate safety and efficacy of a novel, self-applying device for managing OAB symptoms.

Study design, materials and methods

48 patients reporting OAB (MS n=24, idiopathic n=24), were randomized (1:1) to either daily or weekly treatments for 12 weeks with geko™, a novel device stimulating the tibial nerve transcutaneously. Efficacy was assessed using validated questionnaires (ICIQ-OAB, ICIQLUTS-QoL) and bladder diaries filled at weeks 4, 8, and 12. Urinary neurotrophins (Nerve growth factor (NGF) and Brain derived neurotrophic factor) were measured.

Results

34 patients (MS n=19) completed the study. 18 patients responded to treatment (53%); 72% of responders belonged to the MS cohort. Multilevel regression analysis suggested significant improvements in questionnaire scores (ICIQ-OAB –10.2 (–13.5 to –6.9; p=0.001), ICIQLUTS-QOL –40.8 (–57.4 to –24.3; p=0.000)), without differences between weekly and daily-treated arms. No significant adverse effects were reported and patients rated the treatment as easy to use and comfortable. NGF levels at baseline were significantly greater in non-responders (p=0.05).

Concluding message

In this pilot study, a patch device suitable for self-application at home appears to be an effective, safe and convenient alternative for managing MS-related OAB symptoms.

Genetic control of platelet activation in inbred mouse strains

Platelet activation in inbred mouse strains was studied using expression of P-selectin as a marker of activated platelets. P-selectin expression in response to no added stimulus (spontaneous activation) or in response to adenosine diphosphate (ADP) and epinephrine or thrombin, was assessed using a flow cytometric assay. Wide variation in the responsiveness of different strains was observed with strains SJL and AKR in particular showing very high levels of spontaneous activation. Genetic studies suggest that this phenomenon is under control of a small number of genes and that the same loci are probably responsible for the high activation of both SJL and AKR. Bone marrow transplant experiments show that the trait is expressed in the platelet itself. Screening of SWXJ and AKXD recombinant inbred lines suggests that one of the responsible genes is located on chromosome 3.

Accuracy of set-up of thoracic radiotherapy: prospective analysis of 24 patients treated with radiotherapy for lung cancer

In thoracic radiotherapy, a number of factors hinder the use of portal films and electronic portal imaging devices for measuring field placement errors (FPEs). The aim of this study was to assess the accuracy of treatment set-up using simulator check films (SCFs) in radiotherapy for lung cancer. Prospective evaluation was performed on 24 patients. During their radiotherapy, patients returned to the simulator weekly for a minimum of four SCFs, for which the parameters from the original simulator planning film were set, positioning being achieved without fluoroscopy. A total of 96 SCFs were taken. FPEs in left-right (L-R) and superior-inferior (S-I) direction, as well as coronal rotational errors, were measured. The mean absolute FPE was 0.35 cm in the L-R axis and 0.43 cm in the S-I axis. Statistically, the FPEs in the S-I direction were greater than those in the L-R direction (p<0.001). A margin of 0.93 cm between the clinical target volume and the planning target volume would cover 95% of FPEs in the L-R direction, whilst a margin of 1.13 cm is needed for this degree of certainty in the S-I direction. Mean coronal rotational error was 1.6 degrees. Systematic errors were greater than random errors. This study demonstrated that the FPEs were within clinical tolerance (< or = 0.7 cm) in 84.9% of the measurements. The planning margins used in our clinical practice compare favourably with the FPEs in this study.

A randomised controlled trial of the effectiveness of combining video role play with traditional methods of delivering undergraduate medical education

OBJECTIVE

To determine the effectiveness of video role play with structured feedback in improving undergraduate communication skills and application of knowledge in genitourinary medicine.

DESIGN

A blind, randomised, controlled trial.

SUBJECTS AND SETTING

Fourth year undergraduates attending a 5 week attachment in genitourinary medicine during 1997 at a London medical school.

INTERVENTION

A randomly selected sample group of undergraduates were filmed in the role of a doctor interviewing a patient (played by an actor) presenting with a genitourinary (GU) problem. Structured feedback by a GU physician and an educational psychologist was given a week later. The control group of undergraduates did not receive this training intervention.

OUTCOME MEASURES

Student performance in two stations of an objective structured clinical examination (OSCE), administered at the end of their attachment. This tested communication skills and knowledge in GU settings.

RESULTS

132 undergraduates were assessed in the OSCE. 40 of these were in the sample group who received training using video role play with feedback and 92 were in the control group. The sample group scored significantly higher marks than the control group (p<0.001).

CONCLUSIONS

Video role play with structured feedback is effective in improving undergraduate communication skills and application of knowledge in GU medicine settings.

Increased acid-sensing ion channel ASIC-3 in inflamed human intestine

OBJECTIVES

Acid-sensing ion channels (ASICs) are expressed by rat sensory neurons and may mediate pain associated with tissue acidosis after inflammation or injury. Our aim was to examine the molecular forms and localization of ASICs in human intestine and dorsal root ganglia using immunochemical techniques, and to measure the effects of inflammation and injury.

DESIGN AND METHODS

Inflamed Crohn's disease intestine and injured human dorsal root ganglia, with appropriate controls, were studied by Western blotting and immunohistochemistry, using specific affinity-purified ASIC antibodies.

RESULTS

In the Western blot, there was a significant three-fold increase in the mean relative optical density of the ASIC-3 55-kDa band (but not ASIC-1 or ASIC-2) in full-thickness inflamed intestine, as well as in separated muscle and mucosal layers. There was a corresponding trend for an increased immunoreactive density and increased number of ASIC-3-positive neurons in the myenteric and sub-mucous plexus of inflamed intestine. In dorsal root ganglia, immunoreactivity for all ASICs was restricted to a sub-population (about 50%) of small-diameter (nociceptor) sensory neurons, and was generally less intense after injury.

CONCLUSIONS

Increased ASIC-3 in inflamed intestine suggests a role in pain or dysmotility, for which ASICs represent new therapeutic targets.

Vanilloid receptor 1 immunoreactivity in inflamed human bowel

Vanilloid receptor 1 (VR1) is expressed by sensory neurons. Once activated, these neurons evoke the sensation of burning pain and release neuropeptides that induce neurogenic inflammation. We used immunoblotting and immunostaining to estimate the density of VR1 in colonic tissues of patients with inflammatory bowel disease and of controls. Our study results indicate that VR1 immunoreactivity is greatly increased in colonic nerve fibres of patients with active inflammatory bowel disease. Thus, the discovery of new drugs that can bind the VR1 receptor, or antagonise endogenous inflammatory substances that activate this receptor, could lead to new therapies for pain and dysmotility.

Abnormal platelet function and calcium handling in Dahl salt-hypertensive rats

The effect of dietary salt on platelet function and Ca(2+) homeostasis was studied in Dahl (DS) rats, a genetic model of salt-sensitive hypertension. DS rats were fed a high-salt (DSHS) or a low-salt diet (DSLS) for up to 4 weeks, and the effects of salt loading on systolic blood pressure, platelet P-selectin expression, and platelet Ca(2+) homeostasis were measured. The high-salt diet increased blood pressure and markedly increased the amount of ionomycin (IM)-releasable Ca(2+) in platelet intracellular stores (Ca(2+)/IM). The alteration in Ca(2+) stores was not prevented when the hypertension was prevented by treatment with hydralazine and reserpine. The Ca(2+) store filling during platelet exposure to 1 mmol/L Ca(2+) for 5 minutes and the rate of sarcoplasmic/endoplasmic Ca(2+) ATPase-dependent Ca(45) uptake were higher in DSHS compared with that in DSLS. There was a decrease in thrombin-induced Ca(2+) influx in platelets from DSHS; consistent with this, agonist-induced P-selectin expression was decreased. In DSLS, nitric oxide accelerated reloading of platelet Ca(2+) stores after their emptying by thrombin but failed to do so in DSHS. These results indicate that in DS rats, a high-salt diet increases sarcoplasmic/endoplasmic Ca(2+) ATPase activity and the Ca(2+)/IM but decreases the reuptake of Ca(2+) caused by nitric oxide. Decreases in Ca(2+) influx and platelet P-selectin expression might be explained by changes in intracellular Ca(2+) stores in DSHS rats, which apparently is a heritable response to a high-salt diet.

Variation in size and position of the planning target volume in the transverse plane owing to respiratory movement during radiotherapy to the lung

Movement of thoracic tumours with respiration poses a real dilemma in terms of the accuracy of delivering radical radiotherapy in patients with carcinoma of the lung. Movements in the craniocaudal direction have previously been described. This technical note describes ten patients planned for radical lung radiotherapy using CT. The study assesses the maximum impact of respiration on the planning target volume in the transverse plane by comparing the planning CT appearances during quiet respiration with those during full inspiration and full expiration. The study demonstrated the potential impact of respiratory movement on the planning target volume and, hence, implications for local tumour control.

Burger King, Dunkin Donuts and community mental health care

This paper describes the patchwork of cottage industries and human warehousing composing Montréal's 'community mental health care' system. It examines the ways in which this system's clients assemble a collage of ad hoc facilities including homeless shelters, rooming houses, food banks and soup kitchens through which they pursue the fragmented task of daily survival. In their various forms of transit around the city, released psychiatric patients, who rotate in and out of the local psychiatric wards, construe the grammar of urban space. In examining their use of key city sites - malls, fast food outlets, churches and the streets - it becomes apparent that the 'mad' have a particular relationship to these places which they pass through and use on certain terms. Examining the nature of their journeys, the scenes on which they are set and the social relationships of space in play, it is evident that the 'mad' have a particular (dialogical) relationship to the city: a relationship which they share with other, multiply disenfranchised people. This raises significant social questions concerning the politics of city space, and the kinds of fragmented lives and forms of subjectivity that they produce.

Clinical evaluation of an electronic pressure-relieving mattress

A 12-month clinical evaluation of the Talley Quattro Deep Cell 2000 mattress manufactured by Talley Medical was undertaken on both a trauma and surgical ward at the Royal Devon and Exeter Hospital. An identified registered nurse coordinated the evaluation with support from tissue viability clinical nurse specialists. Data on patients, including diagnosis, Waterlow score, pressure area condition and general comments by nurses and patients, were collected. The evaluation involved 35 patients who were at high- to very-high risk of pressure sore formation. The results showed that 16 out of 40 sores healed during the evaluation period and 16 sores remained unchanged. Only one patient developed broken skin while nursed on the mattress. Seventeen patients maintained tissue integrity. Although the study was limited the results suggest that the Talley Quattro Deep Cell 2000 mattress is useful in preventing and managing pressure sores in high- to very high-risk patients.

Cocaine effects on immunocompetent cells: an observation of in vitro cocaine exposure

This study investigated in vitro effects of cocaine on the function of T and B lymphocytes, natural killer cells and macrophages in a mouse model. In mature C57BL/6J mice (60-90 day-old), splenocytes were cultured with cocaine at different concentrations ranging from 4 to 64 microg/ml for 24 h. The exposure to cocaine in vitro was found to affect (1) T cell function, with reduced responses to stimulation of Con-A, PHA and Interleukin 2, and decreased production of gamma-IFN; (2) B cell function, with reduced response to LPS; (3) natural killer cell function, with attenuated killing capacity; (4) monocyte-macrophage function, with decreased ability to inhibit the growth of tumor cells. The results of the study indicated a direct cocaine effect on four major immune competent cells, and the generally suppressive effects of in vitro cocaine exposure may be related to its in vivo action on the immune system.

Deficient platelet-derived nitric oxide and enhanced hemostasis in mice lacking the NOSIII gene

Endothelial nitric oxide synthase (eNOS) has been identified in human platelets. Although platelet-derived nitric oxide (NO) has been shown to inhibit platelet recruitment in vitro, its role in the regulation of the hemostatic response in vivo has not been characterized. To define the role of platelet-derived NO in vivo, we studied mice that lacked a functional eNOS gene (NOSIII). Surface P-selectin expression in platelets from eNOS-deficient mice was not significantly altered; however, bleeding times were markedly decreased in eNOS-deficient versus wild-type mice (77.2+/-3 versus 133.4+/-3 seconds, P<0.00005). To determine the contribution of endothelium- versus platelet-derived NO to the bleeding time, isolated platelets from either eNOS-deficient or wild-type mice were transfused into a thrombocytopenic eNOS-deficient mouse and the bleeding time was measured. The bleeding times in mice transfused with eNOS-deficient platelets were significantly decreased compared with mice transfused with wild-type platelets (Deltableeding time, -24.6+/-9.1 and -3.4+/-5.3 seconds, respectively; P<0.04). Platelet recruitment was studied by measuring serotonin release from a second recruitable population of platelets that were added to stimulated platelets at the peak of NO production. There was 40.3+/-3.7% and 52. 0+/-2.1% serotonin release for platelets added to wild-type or eNOS-deficient platelets, respectively (P<0.05). In summary, mice that lacked eNOS had markedly decreased bleeding times even after endothelial NO production was controlled. These data suggest that the lack of platelet-derived NO alters in vivo hemostatic response by increasing platelet recruitment. Thus, these data support a role for platelet-derived NO production in the regulation of hemostasis.

Interactive effects of cocaine and gender on thymocytes: a study of in vivo repeated cocaine exposure

This study used a mouse model including both sexes to assess the impact of repeat cocaine exposure on the differentiation and function of T cell in thymus. Cocaine hydrochloride in 0.9% saline, 5 mg or 40 mg/kg, was administrated by i.p. injection to C57BL/6 mice for 10 days. Thymocytes were obtained 24 h after the 10th injection. Repeat in vivo cocaine exposure inhibited the proliferation of T lymphocytes in response to Con-A and Con-A plus anti-CD28. The proliferation induced by IL-2 in the Con-A stimulated T blasts was attenuated in cocaine treated mice. These effects were seen at a lower cocaine dose in female mice. The total number of thymocytes was reduced. Although the percentage of mature thymocytes (CD4+ CD8- and CD4- CD8+ cells) was not altered, the absolute cell numbers were attenuated. Both percentage and absolute cell number of immature thymocytes (CD4+ CD8+) decreased and the pre-mature (CD4- CD8-) cells increased. CD28 and CD25 expression were attenuated in Con-A stimulated thymocytes of mice treated with cocaine at 40 mg/kg. Interleukin 2 production was not significantly altered, however, gamma-IFN production was decreased by cocaine exposure at 40 mg/kg. In conclusion, cocaine exerts inhibitory effects on the function of mature thymocytes, and on the differentiation of thymocytes. A gender difference in response to cocaine was noted in that female mice were more sensitive to lower dose of cocaine exposure.

Selective autonomic and sensory deficits in slow transit constipation

Chronic idiopathic constipation is likely to be a heterogeneous condition. Our previous studies on the stimulated sweating response suggested that autonomic dysfunction may be a cause in a subset of patients. Our aims were to test selectively the neural and sweat gland components of the sweat response and to test unmyelinated sensory fibres so as to determine whether a small fibre neuropathy is present. Twelve female patients with proven slow transit constipation and nineteen age-matched healthy volunteers took part in the study. The sensory tests included thermal thresholds and axon reflex vasodilatation in response to intradermal capsaicin, measured with a laser Doppler. Direct and axon reflex sweating was induced with intradermal methacholine and nicotine, respectively, and measured with an evaporimeter. Non-parametric tests were used for statistical comparison with a group of seven control subjects. Results are expressed as medians and range. All four patients who reported constipation from childhood had a selective deficit of unmyelinated afferent fibre function in the feet, with markedly elevated thresholds to warm sensation (controls 5.2; 4.3-10.6, patients 13.8; 11.8-16.1 delta T (degree C), P < 0.02) and heat pain (controls 10.6; 8.2-14.7, patients 18.1; 13.9-22.6 delta T (degree C), P < 0.05) and a reduced response to capsaicin (controls 47.0; 24-117, patients 13.5; 12-30 delta Flux (V), P < 0.005). In contrast, patients with adult onset constipation (n = 7) had a selective neural sweating deficit (controls 49.8; 32.0-61.8; patients 27.7; 7.3-44.3 g/m2 h, P < 0.05), indicating dysfunction of post-ganglionic sympathetic cholinergic fibres. Patients from both groups were shown to have normally functioning sweat glands in direct response to methacholine. Our findings suggest that patients with severe chronic idiopathic constipation may have selective small fibre neuropathies, of which constipation is a manifestation.

Managing pressure relief in a special needs nursing scheme

People admitted to the Royal Devon and Exeter Hospital, who require continued long term nursing care and fulfil at least one of seven identified criteria, can be referred to a special needs scheme for placement in a private local nursing home supported by education, free loan of electronic pressure-relieving equipment and visits to monitor progress. A clinical nurse specialist in tissue viability is also available for advice and the supply of equipment to any residents with tissue viability problems who are referred by nursing home staff. From a total of 293 referrals during the first four years of this scheme, 155 patients have been supported in nursing homes through the scheme. At the time of placement, 71 patients (46%) had pressure sores, all of whom received the free loan of an electronic mattress. A further 21 patients, whose skin integrity was at high risk, also received mattresses. The sores ranged from Grade 2 to Grade 4 (Stirling grading scale). During the study period, only four patients placed under the scheme suffered deterioration in their sores (all immediately prior to death). Over the three years before the scheme began, 14 patients per year were admitted from private nursing homes to an acute hospital with a primary diagnosis of pressure sore. Since the introduction of the scheme this figure has been reduced to nil.

In vivo biotinylation demonstrates that reticulated platelets are the youngest platelets in circulation

In both mice and humans, a subset of platelets can be identified that shows increased labeling with nucleic acid-specific fluorescent dyes, such as thiazole orange. Termed "reticulated platelets," they have been postulated to be platelets that have recently entered the circulation. Their numbers appear to reflect the rate of new platelet production in a number of clinical and experimental situations. To determine whether reticulated platelets really are the youngest platelets in circulation and to estimate the length of time that they are identifiable after entering the circulation, we have employed a technique of "in vivo biotinylation" in mice that labels the entire cohort of circulating cells with covalently bound biotin. Blood samples can then be double-labeled with fluorescent avidin derivatives and thiazole orange, permitting correlated measurement of both surface biotin content and nucleic acid content. The biotinylation occurs rapidly, is complete within 30 minutes, is stable for several days, and does not appear to alter platelet function. The results show that within 24 hours after in vivo biotinylation, platelets appear in the circulation with decreased levels of biotinylation and that these are the reticulated platelets. The estimated lifespan of reticulated platelets is 1.8 days, and the lifespan of all platelets by this method is 4.5 days, which is in agreement with estimates made by other methods.