Helen Parsons

A systematic review of the evidence for single stage and two stage revision of infected knee replacement

BackgroundPeriprosthetic infection about the knee is a devastating complication that may affect between 1% and 5% of knee replacement. With over 79 000 knee replacements being implanted each year in the UK, periprosthetic infection (PJI) is set to become an important burden of disease and cost to the healthcare economy. One of the important controversies in treatment of PJI is whether a single stage revision operation is superior to a two-stage procedure. This study sought to systematically evaluate the published evidence to determine which technique had lowest reinfection rates.MethodsA systematic review of the literature was undertaken using the MEDLINE and EMBASE databases with the aim to identify existing studies that present the outcomes of each surgical technique. Reinfection rate was the primary outcome measure. Studies of specific subsets of patients such as resistant organisms were excluded.Results63 studies were identified that met the inclusion criteria. The majority of which (58) were reports of two-stage revision. Reinfection rated varied between 0% and 41% in two-stage studies, and 0% and 11% in single stage studies. No clinical trials were identified and the majority of studies were observational studies.ConclusionsEvidence for both one-stage and two-stage revision is largely of low quality. The evidence basis for two-stage revision is significantly larger, and further work into direct comparison between the two techniques should be undertaken as a priority.

Magnetic Resonance investigation into the mechanisms involved in the development of high-altitude cerebral edema

Rapid ascent to high altitude commonly results in acute mountain sickness, and on occasion potentially fatal high-altitude cerebral edema. The exact pathophysiological mechanisms behind these syndromes remain to be determined. We report a study in which 12 subjects were exposed to a FiO2 = 0.12 for 22 h and underwent serial magnetic resonance imaging sequences to enable measurement of middle cerebral artery velocity, flow and diameter, and brain parenchymal, cerebrospinal fluid and cerebral venous volumes. Ten subjects completed 22 h and most developed symptoms of acute mountain sickness (mean Lake Louise Score 5.4; p < 0.001 vs. baseline). Cerebral oxygen delivery was maintained by an increase in middle cerebral artery velocity and diameter (first 6 h). There appeared to be venocompression at the level of the small, deep cerebral veins (116 cm3 at 2 h to 97 cm3 at 22 h; p < 0.05). Brain white matter volume increased over the 22-h period (574 ml to 587 ml; p < 0.001) and correlated with cumulative Lake Louise scores at 22 h (p < 0.05). We conclude that cerebral oxygen delivery was maintained by increased arterial inflow and this preceded the development of cerebral edema. Venous outflow restriction appeared to play a contributory role in the formation of cerebral edema, a novel feature that has not been observed previously.

An evaluation of the parents under pressure programme : a study protocol for an RCT into its clinical and cost effectiveness

BackgroundMany babies in the UK are born to drug-dependent parents, and dependence on psychoactive drugs during the postnatal period is associated with high rates of child maltreatment, with around a quarter of these children being subject to a child protection plan. Parents who are dependent on psychoactive drugs are at risk of a wide range of parenting problems, and studies have found reduced sensitivity and responsiveness to both the infant’s physical and emotional needs. The poor outcomes that are associated with such drug dependency appear to be linked to the multiple difficulties experienced by such parents.An increase in understanding about the crucial importance of early relationships for infant well-being has led to a focus on the development and delivery of services that are aimed at supporting parenting and parent–infant interactions. The Parents under Pressure (PuP) programme is aimed at supporting parents who are dependent on psychoactive drugs or alcohol by providing them with methods of managing their emotional regulation, and of supporting their new baby’s development. An evaluation of the PuP programme in Australia with parents on methadone maintenance of children aged 3 to 8 years found significant reductions in child abuse potential, rigid parenting attitudes and child behaviour problems.Methods/designThe study comprises a multicentre randomised controlled trial using a mixed-methods approach to data collection and analysis in order to identify which families are most able to benefit from this intervention.The study is being conducted in six family centres across the UK, and targets primary caregivers of children less than 2.5 years of age who are substance dependent. Consenting participants are randomly allocated to either the 20-week PuP programme or to standard care.The primary outcome is child abuse potential, and secondary outcomes include substance use, parental mental health and emotional regulation, parenting stress, and infant/toddler socio-emotional adjustment scale.DiscussionThis is one the first UK studies to examine the effectiveness of a programme targeting the parenting of substance-dependent parents of infants and toddlers, in terms of its effectiveness in improving the parent–infant relationship and reducing the potential for child abuse.Trial registrationInternational Standard Randomised Controlled Trial Number Register: ISRCTN47282925

Ceramic-on-ceramic bearing fractures in total hip arthroplasty: an analysis of data from the National Joint Registry.

Aims Ceramic‐on‐ceramic (CoC) bearings in total hip arthroplasty (THA) are commonly used, but concerns exist regarding ceramic fracture. This study aims to report the risk of revision for fracture of modern CoC bearings and identify factors that might influence this risk, using data from the National Joint Registry (NJR) for England, Wales, Northern Ireland and the Isle of Man. Patients and Methods We analysed data on 223 362 bearings from 111 681 primary CoC THAs and 182 linked revisions for bearing fracture recorded in the NJR. We used implant codes to identify ceramic bearing composition and generated Kaplan‐Meier estimates for implant survivorship. Logistic regression analyses were performed for implant size and patient specific variables to determine any associated risks for revision. Results A total of 222 852 bearings (99.8%) were CeramTec Biolox products. Revisions for fracture were linked to seven of 79 442 (0.009%) Biolox Delta heads, 38 of 31 982 (0.119%) Biolox Forte heads, 101 of 80 170 (0.126%) Biolox Delta liners and 35 of 31 258 (0.112%) Biolox Forte liners. Regression analysis of implant size revealed smaller heads had significantly higher odds of fracture (chi‐squared 68.0, p < 0.001). The highest fracture risk was observed in the 28 mm Biolox Forte subgroup (0.382%). There were no fractures in the 40 mm head group for either ceramic type. Liner thickness was not predictive of fracture (p = 0.67). Body mass index (BMI) was independently associated with revision for both head fractures (odds ratio (OR) 1.09 per unit increase, p = 0.031) and liner fractures (OR 1.06 per unit increase, p = 0.006). Conclusions We report the largest independent study of CoC bearing fractures to date. The risk of revision for CoC bearing fracture is very low but previous studies have underestimated this risk. There is good evidence that the latest generation of ceramic has greatly reduced the odds of head fracture but not of liner fracture. Small head size and high patient BMI are associated with an increased risk of ceramic bearing fracture.

Utilizing Rapid Multiple-Locus Variable-Number Tandem-Repeat Analysis Typing To Aid Control of Hospital-Acquired Clostridium difficile Infection: a Multicenter Study

ABSTRACT The early identification of outbreaks is crucial for the control of Clostridium difficile infection. This study aimed to determine if the number of hospital-acquired C. difficile infections could be reduced by rapidly typing C. difficile strains using multiple-locus variable-number tandem-repeat analysis (MLVA) compared to typing using PCR ribotyping. A total of 16 hospitals were recruited to the study, and all periods of increased incidence (PIIs) of C. difficile infection were identified. The hospitals were randomized into two study arms, the test and the control, with all isolates typed in the test using MLVA and in the control using PCR ribotyping. Following a PII, each hospital received a structured questionnaire regarding control measures implemented or stopped prior to or following the typing results. During the study period, there were a total of 1,682 hospital-apportioned C. difficile toxin-positive cases, with 868 in the control and 814 in the test, with modeling demonstrating no differences between the two arms. A total of 245 PIIs occurred, involving 785 patients. There was a significant difference in the mean turnaround time between the ribotyping and MLVA typing (13.6 and 5.3 days, respectively [P < 0.001]). The discriminatory ability of MLVA was greater than ribotyping, with 85 outbreaks being confirmed by ribotyping and 62 by MLVA. In the test arm, 40.6% of respondents strongly agreed that the typing result had aided their management of clusters, as opposed to 9.9% in the control. The study demonstrated the utility of rapidly typing C. difficile strains, demonstrating that it aided the management of clusters, enabling effective targeting of infection control resources.

The safety of peri-articular local anaesthetic injection for patients undergoing total knee replacement with autologous blood transfusion: A randomised trial

Intra-operative, peri-articular injection of local anaesthesia is an increasingly popular way of controlling pain following total knee replacement. At the same time, the problems associated with allogenic blood transfusion have led to interest in alternative methods for managing blood loss after total knee replacement, including the use of auto-transfusion of fluid from the patients surgical drain. It is safe to combine peri-articular infiltration with auto-transfusion from the drain. We performed a randomised clinical trial to compare the concentration of local anaesthetic in the blood and in the fluid collected in the knee drain in patients having either a peri-articular injection or a femoral nerve block. Clinically relevant concentrations of local anaesthetic were found in the fluid from the drains of patients having peri-articular injections (4.92 μg/ml (sd 3.151)). However, none of the patients having femoral nerve blockade had detectable levels. None of the patients in either group had clinically relevant concentrations of local anaesthetic in their blood after re-transfusion. The evidence from this study suggests that it is safe to use peri-articular injection in combination with auto-transfusion of blood from peri-articular drains during knee replacement surgery.

Centralisation of radical cystectomies for bladder cancer in England, a decade on from the 'Improving Outcomes Guidance' : the case for super centralisation

To analyse the impact of centralisation of radical cystectomy (RC) provision for bladder cancer in England, on postoperative mortality, length of stay (LoS), complications and re‐intervention rates, from implementation of centralisation from 2003 until 2014. In 2002, UK policymakers introduced the ‘Improving Outcomes Guidance’ (IOG) for urological cancers after a global cancer surgery commission identified substantial shortcomings in provision of care of RCs. One key recommendation was centralisation of RCs to high‐output centres. No study has yet robustly analysed the changes since the introduction of the IOG, to assess a national healthcare system that has mature data on such institutional transformation.

Quality and acceptability of measures of exercise adherence in musculoskeletal settings: a systematic review

Objective. To recommend robust and relevant measures of exercise adherence for application in the musculoskeletal field. Method. A systematic review of measures was conducted in two phases. Phase 1 sought to identify all reproducible measures used to assess exercise adherence in a musculoskeletal setting. Phase 2 identified published evidence of measurement and practical properties of identified measures. Eight databases were searched (from inception to February 2016). Study quality was assessed against the Consensus-based Standards for the Selection of Health Measurement Instruments guidelines. Measurement quality was assessed against accepted standards. Results. Phase 1: from 8511 records, 326 full-text articles were reviewed; 45 reproducible measures were identified. Phase 2: from 2977 records, 110 full-text articles were assessed for eligibility; 10 articles provided evidence of measurement/practical properties for just seven measures. Six were exercise adherence-specific measures; one was specific to physical activity but applied as a measure of exercise adherence. Evidence of essential measurement and practical properties was mostly limited or not available. Assessment of relevance and comprehensiveness was largely absent and there was no evidence of patient involvement during the development or evaluation of any measure. Conclusion. The significant methodological and quality issues encountered prevent the clear recommendation of any measure; future applications should be undertaken cautiously until greater clarity of the conceptual underpinning of each measure is provided and acceptable evidence of essential measurement properties is established. Future research should seek to engage collaboratively with relevant stakeholders to ensure that exercise adherence assessment is high quality, relevant and acceptable.

Rates of voluntary and compulsory psychiatric in-patient treatment in England: an ecological study investigating associations with deprivation and demographics

BACKGROUND Individual variables and area-level variables have been identified as explaining much of the variance in rates of compulsory in-patient treatment. AIMS To describe rates of voluntary and compulsory psychiatric in-patient treatment in rural and urban settings in England, and to explore the associations with age, ethnicity and deprivation. METHOD Secondary analysis of 2010/11 data from the Mental Health Minimum Dataset. RESULTS Areas with higher levels of deprivation had increased rates of in-patient treatment. Areas with high proportions of adults aged 20-39 years had the highest rates of compulsory in-patient treatment as well as the lowest rates of voluntary in-patient treatment. Urban settings had higher rates of compulsory in-patient treatment and ethnic density was associated with compulsory treatment in these areas. After adjusting for age, deprivation and urban/rural setting, the association between ethnicity and compulsory treatment was not statistically significant. CONCLUSIONS Age structure of the adult population and ethnic density along with higher levels of deprivation can account for the markedly higher rates of compulsory in-patient treatment in urban areas.

Variation in compulsory psychiatric inpatient admission in England: a cross-classified, multilevel analysis

BACKGROUND The increasing rate of compulsory admission to psychiatric inpatient beds in England is worrying. Studying variation between places and services could be key to identifying targets for interventions to reverse this trend. We modelled spatial variation in compulsory admissions in England using national patient-level data and quantified the extent to which patient, local-area, and service-setting characteristics accounted for this variation. METHODS This study is a cross-sectional, multilevel analysis of the 2010-11 Mental Health Minimum Data Set (MHMDS). Data from eight provider trusts were excluded, including three independent provider trusts that lacked spatial identification codes. We excluded patients detained under sections of the Mental Health Act concerned only with conveyance to, or assessment in, a registered Place of Safety, or for short-term (≤72 h) assessment only, as these do not in themselves necessarily mean that the person will be admitted to an inpatient mental health bed. MHMDS contained reasonably complete data for a limited number of patient characteristics, namely age, sex, and ethnicity; however, several patient-level variables could not be included in our analysis because of high levels of missing data. Multilevel models were applied with MLwiN to estimate variation in compulsory admission, starting with null (unconditional) models that partitioned total variance in compulsory admission between each level in the model. The primary outcome was compulsory admission to a psychiatric inpatient bed, compared with people admitted voluntarily or receiving only community-based care. FINDINGS Data were available for 1 238 188 patients, covering 64 National Health Service provider trusts (93%) and 31 865 census lower super output areas (LSOAs; 98%). 7·5% and 5·6% of the variance in compulsory admission occurred at LSOA level and provider trust levels, respectively, after adjusting for patient characteristics. Black patients were almost three times more likely to be admitted compulsorily than were white patients (odds ratio [OR] 2·94, 95% CI 2·90-2·98). Compulsory admission was greater in more deprived areas (OR 1·22, 1·18-1·27) and in areas with more non-white residents (OR 1·51, 1·43-1·59), after adjusting for confounders. INTERPRETATION Rates of compulsory admission to inpatient psychiatric beds vary significantly between local areas and services, independent of patient, area, and service characteristics. Compulsory admission rates seem to reflect local factors, especially socioeconomic and ethnic population composition. Understanding how these factors condition access to, and use of, mental health care is likely to be important for developing interventions to reduce compulsion. FUNDING National Institute for Health Research Health Services and Delivery Research Programme.