Venous thromboembolism in adult elective spinal surgery

Aims

To evaluate the incidence of primary venous thromboembolism (VTE), epidural haematoma, surgical site infection (SSI), and 90-day mortality after elective spinal surgery, and the effect of two protocols for prophylaxis.

Patients and Methods

A total of 2181 adults underwent 2366 elective spinal procedures between January 2007 and January 2012. All patients wore anti-embolic stockings, mobilised early and were kept adequately hydrated. In addition, 29% (689) of these were given low molecular weight heparin (LMWH) while in hospital. SSI surveillance was undertaken using the Centers for Disease Control and Prevention criteria.

Results

In patients who only received mechanical prophylaxis, the incidence of VTE was 0.59% and that of SSI 2.1%. In patients who were additionally given LMWH, the incidence of VTE was 0% and that of SSI 0.7%. The unadjusted p-value was 0.04 for VTE and 0.01 for SSI. There were no cases of epidural haematoma or 90-day mortality in either group. When adjusted for case-mix, LMWH remained a significant factor (p = 0.006) for VTE, but not for SSI.

Conclusion

A peri-operative protocol involving mechanical anti-embolism stockings, adequate hydration, and early post-operative mobilisation is effective in significantly reducing the incidence of VTE. The addition of LMWH is safe in patients at higher risk of developing VTE. Cite this article: Bone Joint J 2017;99-B:1204–9.

Change the habit to change the practice: Do audits really ever change anything?

INTRODUCTION

Methicillin resistant staphylococcus aureus (MRSA) eradication by nurses and pre-op induction antibiotics are mandated for emergency surgery, where true status is unknown. We assessed adherence to local MRSA guidelines for patients undergoing emergency hip fracture surgery and employed point of decision prompts to influence clinicians' behaviour.

METHODS

We undertook a retrospective record review for all patients undergoing emergency hip fracture surgery at a UK major trauma centre over 3-months. Demographics, MRSA eradication therapy and antibiotics were recorded. Admission-to-MRSA swab result time was compared to the admit-to-operation time. Posters on induction antibiotics were placed in anaesthetic rooms, stickers on MRSA eradication therapy on nursing care bundles and standards re-audited after 6 months.

RESULTS

The case-mix was similar in both audit cycles: initial audit (n=69, mean age 76.9, range 33-94), re-audit (n=77, mean age 73.8, range 18-95). There was a small rise in adherence to eradication therapy prescription (1% vs 8%) after sticker distribution, although compliance was poor pre and post intervention. Correct antibiotic choice for MRSA unknown patients (18% vs 94%) improved significantly after poster intervention. Operations occurred at a median of 24.05h (Q1 17.6, Q3 32.3) from admission but MRSA swab results returned at a median of 48h (Q1 41.5, Q3 59.5) p=<0.0001.

CONCLUSION

Providing reminders at the points where decisions are to be made are effective. Audit interventions should be easily undertaken and will become habitual if connected in sequence to old behaviours.

Mobile nucleic acid amplification testing (mobiNAAT) for Chlamydia trachomatis screening in hospital emergency department settings

Management of curable sexually-transmitted infections (STI) such as Chlamydia can be revolutionized by highly sensitive nucleic acid testing that is deployable at the point-of-care (POC). Here we report the development of a mobile nucleic acid amplification testing (mobiNAAT) platform utilizing a mobile phone and droplet magnetofluidics to deliver NAAT in a portable and accessible format. By using magnetic particles as a mobile substrate for nucleic acid capture and transport, fluid handling is reduced to particle translocation on a simple magnetofluidic cartridge assembled with reagents for nucleic acid purification and amplification. A mobile phone user interface operating in tandem with a portable Bluetooth-enabled cartridge-processing unit facilitates process integration. We tested 30 potentially Chlamydia trachomatis (CT)-infected patients in a hospital emergency department and confirmed that mobiNAAT showed 100% concordance with laboratory-based NAAT. Concurrent evaluation by a nontechnical study coordinator who received brief training via an embedded mobile app module demonstrated ease of use and reproducibility of the platform. This work demonstrates the potential of mobile nucleic acid testing in bridging the diagnostic gap between centralized laboratories and hospital emergency departments.

Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

Does a modified STarT Back Tool predict outcome with a broader group of musculoskeletal patients than back pain? A secondary analysis of cohort data

OBJECTIVES

The STarT Back Tool has good predictive performance for non-specific low back pain in primary care. We therefore aimed to investigate whether a modified STarT Back Tool predicted outcome with a broader group of musculoskeletal patients, and assessed the consequences of using existing risk-group cut-points across different pain regions.

SETTING

Secondary analysis of prospective data from 2 cohorts: (1) outpatient musculoskeletal physiotherapy services (PhysioDirect trial n=1887) and (2) musculoskeletal primary-secondary care interface services (SAMBA study n=1082).

PARTICIPANTS

Patients with back, neck, upper limb, lower limb or multisite pain with a completed modified STarT Back Tool (baseline) and 6-month physical health outcome (Short Form 36 (SF-36)).

OUTCOMES

Area under the receiving operator curve (AUCs) tested discriminative abilities of the tool's baseline score for identifying poor 6-month outcome (SF-36 lower tertile Physical Component Score). Risk-group cut-points were tested using sensitivity and specificity for identifying poor outcome using (1) Youden's J statistic and (2) a clinically determined rule that specificity should not fall below 0.7 (false-positive rate <30%).

RESULTS

In PhysioDirect and SAMBA, poor 6-month physical health was 18.5% and 28.2%, respectively. Modified STarT Back Tool score AUCs for predicting outcome in back pain were 0.72 and 0.79, neck 0.82 and 0.88, upper limb 0.79 and 0.86, lower limb 0.77 and 0.83, and multisite pain 0.83 and 0.82 in PhysioDirect and SAMBA, respectively. Differences between pain region AUCs were non-significant. Optimal cut-points to discriminate low-risk and medium-risk/high-risk groups depended on pain region and clinical services.

CONCLUSIONS

A modified STarT Back Tool similarly predicts 6-month physical health outcome across 5 musculoskeletal pain regions. However, the use of consistent risk-group cut-points was not possible and resulted in poor sensitivity (too many with long-term disability being missed) or specificity (too many with good outcome inaccurately classified as 'at risk') for some pain regions. The draft tool is now being refined and validated within a new programme of research for a broader musculoskeletal population.

TRIAL REGISTRATION NUMBER

ISRCTN55666618; Post results.

Uniaxial Compressive Properties of Bismaleamid-coated Carbon Microballoons

A uniaxial compression technique employing a nanoindenter equipped with a flat-ended cylindrical tip is used to evaluate the performance of carbon microballoons (CMBs) precipitation-coated with a bismaleamid (APO-BMI) polymer. This coating will eliminate the size and density induced segregation of APO-BMI and CMBs during mold filling and the potentially damaging mixing step wherein CMBs and powdered binder pre-polymer are blended prior to foam molding. To augment the molding of syntactic foams directly from coated CMBs and to aid in the development of a constitutive model for a three-phase syntactic foam, mechanical property evaluation of the coated CMBs is needed. Cured, APO-BMI coated and uncoated CMBs (0.192 g/cm3 tap density) are compressed uniaxially using a modified nanoindenter to obtain the compressive properties of the CMBs in both conditions. These properties included strain-to-failure, failure load, displacement-at-failure, and work of fracture. The 0.192 g/cm 3 tap density CMBs' behavior followed the prior inter-tap density trends between compressive strain and diameter and failure load versus stiffness. The coating is determined to have no statistically significant effect on the mechanical properties of the CMBs. From the combination of this information, the effect of an APO-BMI coating on CMBs of any tap density is inferred.

Endovascular Repair of Ruptured Popliteal Artery Aneurysms: A Case Report and Review of the Literature

OBJECTIVE/BACKGROUND

The objectives were to report the management and outcomes of a 96-year-old man who presented with an acutely swollen right leg due to a ruptured popliteal aneurysm, and to review the relevant literature.

METHODS

A ruptured popliteal artery aneurysm is a rare diagnosis and is one that is often missed at time of presentation. Previous case reports have documented successful outcomes following surgical repair, and a smaller number following endovascular repair. This is a case report of a 96-year-old man who eventually underwent endovascular repair of a ruptured popliteal artery aneurysm after a delay in diagnosis. A literature review was performed to analyse published data in this field.

RESULTS

The patient underwent an uncomplicated endovascular repair with a GORE^® VIABAHN^® stent. A 15-week follow-up ultrasound demonstrated biphasic flow in a patent stent-graft with an unchanged aneurysm sac size and no evidence of an endoleak. A review of the literature demonstrated nine cases of ruptured non-mycotic popliteal artery aneurysms treated endovascularly. Seven cases survived the postoperative period, three had no follow-up recorded, and four cases had patent stent-grafts at time of follow-up.

CONCLUSION

Safe and effective endovascular repair of a ruptured popliteal artery aneurysm with endograft patency seen at the 15-week follow-up is reported. Review of the literature suggests that open repair remains the first-line management choice; however, endovascular repair is a valuable alternative. There is a further need for longer-term monitoring of endograft patency following endovascular repair.

Systemic lupus erythematous with recurrent Guillain -Barré-like syndrome treated with intravenous immunoglobulins

We report on an unusual case of a young African male with systemic lupus erythematosus who developed an acute, severe Guillain-Barré-like peripheral neuropathy associated with ascites. The illness appeared to respond dramatically to a short course of intravenous immunoglobulins. Eight months later he had recurrence of identical features.He required respiratorysupport.On this occasion there was no response to intravenousimmunoglobulins or other measures and he died of sepsis after a protracted period of paralysis.

A STUDY OF THE IMAGE QUALITY OF COMPUTED TOMOGRAPHY ADAPTIVE STATISTICAL ITERATIVE RECONSTRUCTED BRAIN IMAGES USING SUBJECTIVE AND OBJECTIVE METHODS

The recent reintroduction of iterative reconstruction in computed tomography has facilitated the realisation of major dose saving. The aim of this article was to investigate the possibility of achieving further savings at a site with well-established Adaptive Statistical iterative Reconstruction (ASiR™) (GE Healthcare) brain protocols. An adult patient study was conducted with observers making visual grading assessments using image quality criteria, which were compared with the frequency domain metrics, noise power spectrum and modulation transfer function. Subjective image quality equivalency was found in the 40-70% ASiR™ range, leading to the proposal of ranges for the objective metrics defining acceptable image quality. Based on the findings of both the patient-based and objective studies of the ASiR™/tube-current combinations tested, 60%/305 mA was found to fall within all, but one, of these ranges. Therefore, it is recommended that an ASiR™ level of 60%, with a noise index of 12.20, is a viable alternative to the currently used protocol featuring a 40% ASiR™ level and a noise index of 11.20, potentially representing a 16% dose saving.

A comparison of two digital mammography systems: are there any differences?

AIM

To compare the performance of two newly introduced digital mammography technologies (Sectra and Hologic) to the Welsh breast-screening service; specifically, whether there are differences in the number, type, size, and grade of tumour identified.

MATERIALS AND METHODS

This was a retrospective study of a prospectively collected database of 50,000 consecutive screening episodes from 2012; clients were aged 49-88 years (mean 61.9 years). All studies were double-blind read by two readers. All tumours identified in the two arms of the study were detailed and compared specifically with regards to type (ductal or lobular) size, grade, and whether invasive or non-invasive. Performance was analysed for any statistically significant differences.

RESULTS

Twenty-five thousand consecutive women were screened with Hologic (recall rate 5.9% of which 18% were cancer) and 25,000 were screened with Sectra digital mammography (recall rate 4.3% and 22% were cancer). Five hundred tumours were found with no significant difference in invasive cancer detection or between ductal or lobular subtypes. The Hologic system detected 267 tumours; of which 81 (30.33%) were non-invasive (3.24 per 1000), compared to the Sectra system with 233 cancers overall including 36 non-invasive (15.45%, 1.44 per 1000). The difference in non-invasive lesions (mainly ductal carcinoma in situ [DCIS]) detection was significant (p<0.001); 38% of which were high nuclear grade (HNG) using Hologic and 50% HNG lesions using Sectra. There was no significant difference in non-invasive size between the two technologies. The mean glandular dose received using the Sectra system was significantly less (0.7 mGy) compared to the Hologic system (1.6 mGy) for a 50-60 mm breast thickness.

CONCLUSIONS

Population breast screening is frequently criticised for identifying lesions irrelevant to long-term outcomes or life expectancy and although the two systems seem comparable in terms of invasive cancer detection, a statistically significant difference in the detection of non-invasive lesions was seen, not reported in previous studies. This is a contentious issue, as identifying more DCIS has the potential to over-diagnose screened women leading to increased morbidity, higher "cancer detection rates", longer cancer waiting times, and reduced patient psychological wellbeing. The Sectra system is able to deliver a similar invasive detection cancer delivering a much lower dose mammogram, which is important in limiting overall population radiation dose. Further study as to whether the differences in tumour detection rates are clinically significant long term are now required.

Long-term outcome of prucalopride for chronic constipation: a single-centre study

AIM

Newer 5-hydroxytryptamine agonists, such as prucalopride, have been demonstrated to be effective in the short term for treatment of chronic constipation. To date, few studies have investigated their medium- and long-term effectiveness.

METHOD

An analysis was carried out of a prospectively maintained database of all patients started on prucalopride for chronic constipation between April 2011 and April 2014. Cleveland Clinic Constipation Score (CCCS) questionnaires were administered before starting treatment with prucalopride and at the first follow-up visit to assess change in CCCS scores in 50 randomly selected patients.

RESULTS

A total of 155 patients (median age: 47 years; seven men) were started on prucalopride in this period. Of these, 16 (10%) had slow-transit constipation, 31 (20%) had obstructive defaecation syndrome and 30 (19%) had a combination of both. Of these 155 patients, 78% patients were on three or more laxatives at the time of starting prucalopride. Patients were started on 1 mg or 2 mg according to their age. The median follow-up period was 24 (range: 4-40) months. At the first follow-up visit, 106 (68%) patients reported good symptomatic improvement, whereas the remainder had no response. Third of initial responders showed decreased efficacy after a median duration of 6 months and needed regular laxatives/irrigation. Of the 50 patients who filled in the CCCS questionnaires (15 patients were nonresponders), 32 (64%) reported improved scores with a median improvement of two points per criterion.

CONCLUSION

This study provides evidence that prolonged use of prucalopride is effective in achieving a sustained benefit in the majority of patients.

Fc Gamma Receptor 3A and 2A Polymorphisms Do Not Predict Response to Rituximab in Follicular Lymphoma

PURPOSE

Preclinical studies suggest that SNPs in the Fc gamma receptor (FCGR) genes influence response to rituximab, but the clinical relevance of this is uncertain.

EXPERIMENTAL DESIGN

We prospectively obtained specimens for genotyping in the rituximab extended schedule or re-treatment trial (RESORT) study, in which 408 previously untreated, low tumor burden follicular lymphoma (FL) patients were treated with single agent rituximab. Patients received rituximab in 4 weekly doses and responders were randomized to rituximab re-treatment (RR) upon progression versus maintenance rituximab (MR). SNP genotyping was performed in 321 consenting patients.

RESULTS

Response rates to initial therapy and response duration were correlated with the FCGR3A SNP at position 158 (rs396991) and the FCGR2A SNP at position 131 (rs1801274). The response rate to initial rituximab was 71%. No FCGR genotypes or grouping of genotypes were predictive of initial response. A total of 289 patients were randomized to RR (n = 143) or to MR (n = 146). With a median follow-up of 5.5 years, the 3-year response duration in the RR arm and the MR arm was 50% and 78%, respectively. Genotyping was available in 235 of 289 randomized patients. In patients receiving RR (n = 115) or MR (n = 120), response duration was not associated with any FCGR genotypes or genotype combinations.

CONCLUSIONS

Based on this analysis of treatment-naïve, low tumor burden FL, we conclude that the FCGR3A and FCGR2A SNPs do not confer differential responsiveness to rituximab.

Should General Practitioners Issue a Sick Certificate to Employees Who Consult for Low Back Pain in Primary Care?

PURPOSE

Back pain is a common problem and has significant societal impact. Sickness certification is commonly issued to patients consulting their general practitioner with low back pain. The aim of this study was to investigate the association of certification for low back pain with clinical outcomes and cost consequences.

METHODS

A prospective cohort study using linked questionnaire and medical record data from 806 low back pain patients in 8 UK general practices: comparison of 116 (14.4%) who received a sickness certificate versus 690 who did not receive certification. The primary clinical measure was the Roland and Morris Disability Questionnaire (RMDQ). Data on back pain consultation and work absenteeism were used to calculate healthcare and societal costs.

RESULTS

Participants issued a sickness certificate had higher back-related disability at baseline consultation and 6-month follow-up [mean difference 3.1 (95% CI 1.8, 4.4) on the RMDQ], indicating worse health status. After fully adjusting for baseline differences, most changes in clinical outcomes at 6 months were not significantly different between study groups. Productivity losses were significantly higher for the certification group, with most absence occurring after the expected end of certification; mean difference in costs due to absenteeism over 6 months was £1,956 (95% CI £941, £3040).

CONCLUSIONS

There was no clear evidence of a difference in clinical outcomes between individuals issued a sickness certificate and those not issued a certification for their back pain. With little overall contrast in clinical outcomes, policy makers and care providers may wish to draw on the likely difference in societal costs alongside issues in ethical and moral care in their consideration of patient care for low back pain.

Effect of maraviroc on non-R5 tropic HIV-1: refined analysis of subjects from the phase IIb study A4001029

We characterized maraviroc susceptibility of dual/mixed tropic viruses from subjects enrolled onto phase IIb study A4001029. Maraviroc baseline plasma samples from 13 multidrug-experienced subjects were sequenced and the HIV-1-env gene cloned into pNL4.3Δenv to obtain recombinant viruses. The V3 region was sequenced by the Sanger method and ultradeep sequencing. By analysing subjects having a weighted optimized background therapy susceptibility (wOBT) score of <1, 3/7 subjects were characterized by good in vivo and in vitro response to maraviroc therapy. Molecular docking simulations allowed us to rationalize the maraviroc susceptibility of dual/mixed tropic viruses. A subset of subjects with dual/mixed tropic viruses responded to maraviroc. Further investigations are warranted of CCR5 antagonists in subjects carrying dual/mixed tropic virus that explore the feasible use of maraviroc in subjects that is potentially larger than those infected with a pure R5 virus.

Abstract 5607: BRAF and KRAS mutation testing in plasma cell-free DNA with ICE COLD-PCR in patients with advanced cancers

Background: Cell-free (cf) DNA in the plasma of cancer patients offers an easily obtainable, low-risk, inexpensive, and repeatedly available source of biologic material for mutation analysis and monitoring of molecular changes throughout cancer therapy.

Methods: DNA in plasma from patients with advanced cancers who progressed on systemic therapy was tested for BRAF V600 and KRAS G12 and G13 mutations using the ICE COLD-PCR platform. ICE COLD-PCR, “Improved and Complete Enrichment COamplification at Lower Denaturation,” selectively amplifies mutant DNA by exploiting differences in denaturation temperatures between mutant DNA duplexes and normal “wild-type” DNA duplexes. KRAS Exon 2 and BRAF Exon 15 ICE COLD-PCR was performed on plasma samples. Amplicons were analyzed using Sanger sequencing and results were compared to the mutation status of archival primary or metastatic tumor tissue as determined in a CLIA-certified laboratory during routine clinical care.

Results: Plasma samples from 77 patients with advanced cancers and known tumor tissue BRAF and/or KRAS mutation status (colorectal cancer, n=38; melanoma, n=17; non-small cell lung cancer, n=7; other cancers, n=15) were obtained before treatment and, if possible, sequentially during therapy and tested for BRAF (42), KRAS (34) or BRAF and KRAS (1) mutations in cfDNA. BRAF mutations were detected in 93% (40/43) of archival tumor samples compared to 70% (30/43) of plasma cfDNA samples (agreement 77%). In addition, 20 patients treated with systemic therapy had serial plasma samples collected and the change in relative abundance of BRAF-mutant compared to wild-type cfDNA corresponded with the clinical course of 15 patients and was discrepant for 1 patient; in 5 patients no BRAF mutated cfDNA was detected at any time point. KRAS mutations were detected in 83% (29/35) of archival tumor samples compared to 74% (26/35) of plasma cfDNA samples (agreement 80%). In addition, 12 patients treated with systemic therapy had serial plasma collected and the change in relative abundance of KRAS-mutant compared to wild-type cfDNA corresponded with clinical course in 10 patients; in 2 patients no KRAS mutated cfDNA was detected at any time point.

Conclusions: Detection of BRAF and KRAS mutations in cfDNA can provide a fast and noninvasive alternative to mutation testing in tumor tissue with a potential to be used for monitoring response to cancer therapy.

Citation Format: Filip Janku, Ben Legendre, Katherine Richardson, Gerald S. Falchook, Aung Naing, Veronica R. Holley, Siqing Fu, David S. Hong, Sarina A. Piha-Paul, Jennifer J. Wheler, Ralph G. Zinner, Vivek Subbiah, Apostolia M. Tsimberidou, Daniel D. Karp, Vanda M. Stepanek, Goran Cabrilo, Rajyalakshmi Luthra, Funda Meric-Bernstam, Agop Y. Bedikian, Bryan K. Kee, Cathy Eng, Michael J. Overman, Kevin B. Kim, Amy Kruempel, Jaclyn Pope, Courtney Cubrich, Grant Wu, Marcia Lewis, Razelle Kurzrock. BRAF and KRAS mutation testing in plasma cell-free DNA with ICE COLD-PCR in patients with advanced cancers. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5607. doi:10.1158/1538-7445.AM2014-5607