Description of serum symmetric dimethylarginine concentration and of urinary SDS-AGE pattern in dogs with ACTH dependent hyperadrenocorticism

Serum symmetric dimethylarginine (SDMA) and patterns of urinary protein separated by sodium dodecyl sulfate agarose gel electrophoresis (SDS-AGE) have not been investigated as biomarkers in dogs with ACTH-dependent hyperadrenocorticism (ADHAC). This exploratory prospective study aimed to evaluate SDMA, serum creatinine (sCR), and SDS-AGE in dogs with ADHAC with and without proteinuria (ADHAC-P and ADHAC-nP, respectively). Thirty-five pet dogs classified as ADHAC-P (n=16), ADHAC-nP (n=6) and healthy (n=13) were included. Renal biomarkers were evaluated in all dogs at diagnosis. Baseline concentration of SDMA was not significantly different between the three groups (P = 0.15) whereas sCr was significantly lower in dogs in ADHAC dogs compared to healthy dogs (88.0 µmol/L [70.4-132.6; 79.2-114.4]) whether they had proteinuria or not (P = 0.014 and 0.002, respectively). However, baseline concentrations of sCr and SDMA were not significantly different between dogs with ADHAC-P dogs (SDMA, 8 µg/dL [5-12; 7-9]; sCr, 57.2 µmol/L [35.2-212.2; 52.8-92.4]) and ADHAC-nP dogs (SDMA, 8.5 µg/dL [7-13; 8-10]; sCr, 70.4 µmol/L [61.6-79.2; 61.6-70.4]) (P = 0.35 and P = 0.41, respectively). Proteinuria in dogs with ADHAC-P was mainly of glomerular origin (SDS-AGE pattern: glomerular in 10/16 dogs; mixed glomerular/tubular in four dogs). In our study, SDMA was neither significantly different in dogs with ADHAC whether they were proteinuric or not, nor between ADHAC and healthy dogs. Urinary electrophoresis provides additional information to the UPC and further investigations are needed to determine whether it may help identify dogs with ADHAC-P requiring specific antiproteinuric treatment.

Clinical management of adolescents and young adults suffering from sarcoma in the French Rhône-Alpes region: A prospective exhaustive cohort with 10 years follow up.

INTRODUCTION: Survival of adolescents and young adults (AYA) with sarcoma is lower than in younger patients. The objective of this study was to describe the regional healthcare circuits, the differences in the management between adult, paediatric and mixed units and to assess the prognostic impact of compliance with clinical practice guidelines (CPGs) on overall survival (OS) and on relapse free survival (RFS). MATERIALS AND METHODS: Retrospective analysis of the management and long term follow-up of all 13-25 year old patients with a sarcoma diagnosed in the Rhône-Alpes area between 2000 and 2005. RESULTS: 140 patients satisfied inclusion criteria and were selected. The majority of 13-25 year old patients were treated in paediatric units. Joint management resulted in a higher rate of discussion in multidisciplinary tumour board, inclusion in clinical trials, and fertility preservation. Non-compliance with guidelines was observed in 65% of cases. Overall compliance was not reported to correlate to survival. Compliance of radiotherapy with CPG's seemed associated with a better prognosis for OS (HR = 0.20, 95% CI = [0.10-0.40]; p < 0.0001) and RFS (HR = 0.18, 95% CI = [0.09-0.37; p < 0.0001) as well as compliance of surgery for OS (HR = 0.43, 95% CI = [0.23-0.81]; p = 0.01). Multivariate Cox regression analysis revealed other independent predictors of OS like age at diagnosis, stage and histological subtype. CONCLUSIONS: Management of AYA in joint units seems to improve the quality of care. Compliance of surgery and radiotherapy with CGP's seems to improve survival.

Team planning discussion and clinical performance: a prospective, randomised, controlled simulation trial.

Planning held before emergency management of a critical situation might be an invaluable asset for optimising team preparation. The purpose of this study was to investigate whether a brief planning discussion improved team performance in a simulated critical care situation. Forty-four pairs of trainees in anaesthesia and intensive care were randomly allocated to either an intervention or control group before participating in a standardised simulated scenario. Twelve different scenarios were utilised. Groups were stratified by postgraduate year and simulated scenario, and a facilitator was embedded in the scenario. In the intervention group, the pairs had an oral briefing followed by a 4-min planning discussion before starting the simulation. The primary end-point was clinical performance, as rated by two independent blinded assessors on a score of 0-100 using video records and pre-established scenario-specific checklists. Crisis resource management and stress response (cognitive appraisal ratio) were also assessed. Two pairs were excluded for technical reasons. Clinical performance scores were higher in the intervention group; mean (SD) 51 (9) points vs. 46 (9) in the control group, p = 0.039. The planning discussion was also associated with higher crisis resource management scores and lower cognitive appraisal ratios, reflecting a positive response. A 4-min planning discussion before a simulated critical care situation improved clinical team performance and cognitive appraisal ratios. Team planning should be integrated into medical education and clinical practice.

Deterministic and statistical characterization of rigid frame porous materials from impedance tube measurements.

A method to characterize macroscopically homogeneous rigid frame porous media from impedance tube measurements by deterministic and statistical inversion is presented. Equivalent density and bulk modulus of the samples are reconstructed with the scattering matrix formalism, and are then linked to its physical parameters via the Johnson-Champoux-Allard-Lafarge model. The model includes six parameters, namely the porosity, tortuosity, viscous and characteristic lengths, and static flow and thermal permeabilities. The parameters are estimated from the measurements in two ways. The first one is a deterministic procedure that finds the model parameters by minimizing a cost function in the least squares sense. The second approach is based on statistical inversion. It can be used to assess the validity of the least squares estimate, but also presents several advantages since it provides valuable information on the uncertainty and correlation between the parameters. Five porous samples with a range of pore properties are tested, and the pore parameter estimates given by the proposed inversion processes are compared to those given by other characterization methods. Joint parameter distributions are shown to demonstrate the correlations. Results show that the proposed methods find reliable parameter and uncertainty estimates to the six pore parameters quickly with minimal user input.

Cluster randomized trial to evaluate the impact of team training on surgical outcomes.

BACKGROUND: The application of safety principles from the aviation industry to the operating room has offered hope in reducing surgical complications. This study aimed to assess the impact on major surgical complications of adding an aviation-based team training programme after checklist implementation. METHODS: A prospective parallel-group cluster trial was undertaken between September 2011 and March 2013. Operating room teams from 31 hospitals were assigned randomly to participate in a team training programme focused on major concepts of crew resource management and checklist utilization. The primary outcome measure was the occurrence of any major adverse event, including death, during the hospital stay within the first 30 days after surgery. Using a difference-in-difference approach, the ratio of the odds ratios (ROR) was estimated to compare changes in surgical outcomes between intervention and control hospitals. RESULTS: Some 22 779 patients were enrolled, including 5934 before and 16 845 after team training implementation. The risk of major adverse events fell from 8·8 to 5·5 per cent in 16 intervention hospitals (adjusted odds ratio 0·57, 95 per cent c.i. 0·48 to 0·68; P < 0·001) and from 7·9 to 5·4 per cent in 15 control hospitals (odds ratio 0·64, 0·50 to 0·81; P < 0·001), resulting in the absence of difference between arms (ROR 0·90, 95 per cent c.i. 0·67 to 1·21; P = 0·474). Outcome trends revealed significant improvements among ten institutions, equally distributed across intervention and control hospitals. CONCLUSION: Surgical outcomes improved substantially, with no difference between trial arms. Successful implementation of an aviation-based team training programme appears to require modification and adaptation of its principles in the context of the the surgical milieu. Registration number: NCT01384474 (http://www.clinicaltrials.gov).

How does gatekeeper training improve suicide prevention for elderly people in nursing homes? A controlled study in 24 centres.

BACKGROUND: The death rate due to suicide in elderly people is particularly high. As part of suicide selective prevention measures for at-risk populations, the WHO recommends training "gatekeepers". METHODS: In order to assess the impact of gatekeeper training for members of staff, we carried out a controlled quasi-experimental study over the course of one year, comparing 12 nursing homes where at least 30% of the staff had undergone gatekeeper training with 12 nursing homes without trained staff. We collected data about the residents considered to be suicidal, their management further to being identified, as well as measures taken at nursing home level to prevent suicide. RESULTS: The two nursing home groups did not present significantly different characteristics. In the nursing homes with trained staff, the staff were deemed to be better prepared to approach suicidal individuals. The detection of suicidal residents relied more on the whole staff and less on the psychologist alone when compared to nursing homes without trained staff. A significantly larger number of measures were taken to manage suicidal residents in the trained nursing homes. Suicidal residents were more frequently referred to the psychologist. Trained nursing homes put in place significantly more suicide prevention measures at an institutional level. CONCLUSIONS: Having trained gatekeepers has an impact not only for the trained individuals but also for the whole institution where they work, both in terms of managing suicidal residents and routine suicide prevention measures.

Surface waves in granular phononic crystals.

The existence of surface elastic waves at a mechanically free surface of granular phononic crystals is studied. The granular phononic crystals are made of spherical particles distributed periodically on a simple cubic lattice. It is assumed that the particles are interacting by means of normal, shear, and bending contact rigidities. First, Rayleigh-type surface acoustic waves, where the displacement of the particles takes place in the sagittal plane while the particles possess one rotational and two translational degrees of freedom, are analyzed. Second, shear-horizontal-type waves, where the displacement of the particles is normal to the sagittal plane while the particles possess one translational and two rotational degrees of freedom are studied. The existence of zero-group-velocity surface acoustic waves of Rayleigh type is theoretically predicted and interpreted. A comparison with surface waves predicted by the reduced Cosserat theory is performed, and some limitations of the latter are established.

Preoperative CT and MRI prediction of non-resectability in patients treated for pseudomyxoma peritonei from mucinous appendiceal neoplasms.

AIMS: To evaluate computed tomography (CT) and magnetic resonance imaging (MRI) findings for sign of hepatoduodenal ligament and small bowel non-resectability in patients with pseudomyxoma peritonei (PMP) and to compare assessments made by the radiologist based on their experiences. METHODS: Between January 2009 and June 2014, all consecutive patients with PMP selected for curative surgery were scheduled to undergo CT and MRI examinations within two days of their surgery. Several imaging findings of hepatoduodenal ligament and small bowel involvements were retrospectively evaluated by a senior and a junior radiologist and compared with surgical findings. RESULTS: Of the 82 patients enrolled in the study, 11 had non-resectable lesions with hepatoduodenal ligament infiltration (n = 4) and/or extensive small bowel involvement (n = 9). All patients underwent CT and 73 underwent MRI scan. Infiltration of the adipose tissue of the hepatoduodenal ligament by mucinous tumor was associated with non-resectability. For the senior and junior radiologists, the sensitivity and specificity were 75% and 100%, and 50% and 100% on CT (kappa value (k) = 0.79); 67% and 100%, and 33% and 97% on MRI (k = 0.38), respectively. Diffuse involvement of the mesentery and/or the small bowel serosa was also associated with non-resectability. For the senior and junior radiologists, the sensitivity and specificity were 67% and 100%, and 56% and 99% on CT (k = 0.82); 88% and 100%, and 38% and 100% on MRI (k = 0.58), respectively. CONCLUSION: CT and MRI can both contribute to the diagnosis of non-resectability in patients with PMP. The use of MRI to identify small bowel involvement, in particular, benefits from a more experienced radiologist.

Implementation of a computerized system in pediatric wards to improve nutritional care: a cluster randomized trial.

BACKGROUND/OBJECTIVES: Malnutrition occurs frequently in hospitalized children. We aimed to assess whether a computerized system could lead to improved clinical practices in malnourished children. SUBJECTS/METHODS: Healthcare workers (242) from six departments in a pediatric university hospital participated in a cluster randomized trial, studying 1457 malnourished children hospitalized from September 2009 to August 2011. Following a baseline observational pre-intervention period, all departments were randomized into either intervention or control arms. A computerized malnutrition-screening system was implemented in the intervention group to automatically trigger a dietetic referral in real time. Furthermore, the nutrition support team conducted an awareness campaign with healthcare workers and a leadership-based strategy to reinforce the message during the entire study period. Adherence to practice guidelines (daily weights, investigation of etiology for malnutrition, management by a dietitian and application of refeeding protocols) was compared between pre- and post-intervention periods in both the intervention and trial arms. RESULTS: When compared with the pre-intervention period, the clinical practices were significantly improved within the intervention arm for every outcome (P<0.01), whereas remained unchanged in the control arm. In addition, during the post-intervention period, malnutrition etiology investigation by physicians (adjusted odds ratio (OR) of 4.4, 95% confidence interval (CI) 1.7-11.8, P=0.003) and management by a dietitian (OR 2.7, 95% CI 1.0-6.9, P=0.046) occurred more frequently in the intervention clusters. CONCLUSIONS: Implementation of an electronic system to detect malnutrition in real time was associated with a rapid improvement in clinical practices for better care of hospitalized children.

Is it possible to limit the risks of thyroid surgery?

OBJECTIVE: Inferior laryngeal nerve (ILN) palsy and hypocalcemia remain the two most frequent major complications after thyroid surgery. Their occurrences may be explained by the influence of factors related to the patient, the surgical procedure, thyroid pathology, or the surgeon's technique. This study aims To assess whether systematically following a rigorous surgical technique during thyroidectomy affects postoperative complications and long-term patient recovery. METHODS: We conducted a multicenter, cross-sectional study of prospectively collected data in five high-volume referral centers enrolling all patients who underwent thyroid surgery between April 2008 and December 2009. Inferior laryngeal nerve (ILN) palsy and hypocalcemia were systematically assessed during hospitalization based on objective criteria. A six-month follow-up was conducted in cases of early complications. Multivariate regression models were computed to quantify their relationship with potential risk factors. RESULTS: A total of 3574 thyroid procedures were completed. Non-visualization of the ILN during dissection and a large thyroid mass were major risk factors for permanent ILN palsy (OR, 4.17 and 2.61, p<0.01) and persistent complications after initial injury (OR, 4.17 and 2.42, p<0.05). The presence of thyroiditis on the surgical specimen was an independent risk factor for permanent hypoparathyroidism and poor recovery after initial dysfunction (OR, 1.76 and 1.88, p<0.05). CONCLUSIONS: Thorough meticulous technique in thyroid surgery is a determinant of ILN function but fails to prevent persistent hypoparathyroidism.

Systematic review of methodological quality of individual performance measurement in surgery.

BACKGROUND: Calls for greater transparency with improved quality, safety and outcomes have led to performance tracking of individual surgeons. This study evaluated the methodology of studies investigating individual performance in surgery. METHODS: MEDLINE, Embase, PsycINFO, AMED and the Cochrane Database of Systematic Reviews (from their inception to July 2014) were searched. Two authors independently reviewed citations using predetermined inclusion and exclusion criteria; 91 data points per study were extracted. RESULTS: The search strategy yielded 8514 citations; 101 were eligible, comprising 1 006 037 procedures by 14 455 surgeons. Thirty-four studies were prospective and 66 were retrospective. The aim of the studies was either to assess individual performance and describe the learning curve of a procedure, to describe factors influencing performance, or to describe methods for routine performance monitoring. Some 51·5 per cent of the studies investigated 500 or fewer procedures. Most (77 of 101) were single-centre studies. Less than half of the studies (42, 41·6 per cent) employed statistical modelling or stratification to adjust performance measures. Forty studies (39·6 per cent) adjusted outcomes for case mix. Seventeen (16·8 per cent) adjusted metrics for surgeon-specific factors. Thirteen studies (12·9 per cent) considered clustering in their analyses. The most frequent outcome studied was duration of operation (59·4 per cent), followed by complication rate (45·5 per cent) and reoperation rate (29·7 per cent); 15·8 per cent of studies recorded mortality, and 4·0 per cent explored patient satisfaction. Only 48·5 per cent of studies displayed procedural learning curves using a graph. CONCLUSION: There exist substantial shortcomings in methodological quality, outcome measurements and quality improvement evaluation among current studies of individual surgical performance. Methodological guidelines should be established to ensure that assessments are valid.

[Determination of the 120-day post prostatic biopsy mortality rate]. / Mesure de la mortalité à 120 jours après biopsie de la prostate.

OBJECTIVE: Concerning death-rates were reported following prostate biopsy but the lack of contexts in which event occurred makes it difficult to take any position. Therefore, we aimed to determine the 120-day post-biopsy mortality rate. MATERIAL AND METHODS: Between 2000 and 2011, 8804 men underwent prostate biopsy in the hospice civils de Lyon. We studied retrospectively, the mortality rate after each of the 11,816 procedures. Biopsies imputability was assessed by examining all medical records. Dates of death were extracted from our local patient management database, which is updated trimestrially with death notifications from the French National Institute for Statistics and Economic Studies. RESULTS: In our study 42 deaths occurred within 120days after 11,816 prostate biopsies (0.36%). Of the 42 records: 9 were lost to follow-up, 3 had no identifiable cause of death, 28 had an intercurrent event ruling out prostate biopsy as a cause of death. Only 2 deaths could be linked to biopsy. CONCLUSIONS: We reported at most 2 deaths possibly related to prostate biopsy over 11,816 procedures (0.02%). We confirmed the fact that prostate biopsies can be lethal but this rare outcome should not be considered as an argument against prostate screening given the circumstances in which it occurs. LEVEL OF EVIDENCE: 5.

Localized transversal-rotational modes in linear chains of equal masses.

The propagation and localization of transversal-rotational waves in a two-dimensional granular chain of equal masses are analyzed in this study. The masses are infinitely long cylinders possessing one translational and one rotational degree of freedom. Two dispersive propagating modes are predicted in this granular crystal. By considering the semi-infinite chain with a boundary condition applied at its beginning, the analytical study demonstrates the existence of localized modes, each mode composed of two evanescent modes. Their existence, position (either in the gap between the propagating modes or in the gap above the upper propagating mode), and structure of spatial localization are analyzed as a function of the relative strength of the shear and bending interparticle interactions and for different boundary conditions. This demonstrates the existence of a localized mode in a semi-infinite monatomic chain when transversal-rotational waves are considered, while it is well known that these types of modes do not exist when longitudinal waves are considered.

Absorption of a rigid frame porous layer with periodic circular inclusions backed by a periodic grating.

The acoustic properties of a periodic rigid frame porous layer with multiple irregularities in the rigid backing and embedded rigid circular inclusions are investigated theoretically and numerically. The theoretical representation of the sound field in the structure is obtained using a combination of multipole method that accounts for the periodic inclusions and multi-modal method that accounts for the multiple irregularities of the rigid backing. The theoretical model is validated against a finite element method. The predictions show that the acoustic response of this structure exhibits quasi-total, high absorption peaks at low frequencies which are below the frequency of the quarter-wavelength resonance typical for a flat homogeneous porous layer backed by a rigid plate. This result is explained by excitation of additional modes in the porous layer and by a complex interaction between various acoustic modes. These modes relate to the resonances associated with the presence of a profiled rigid backing and rigid inclusions in the porous layer.

Lugol chromo-endoscopy versus narrow band imaging for endoscopic screening of esophageal squamous-cell carcinoma in patients with a history of cured esophageal cancer: a feasibility study.

To date, Lugol chromo-endoscopy is the reference technique to detect an esophageal neoplasia in patients with prior esophageal squamous-cell carcinoma (ESCC), but is not easy to perform without general anesthesia, which can limit its use in routine practice. The objective of this study were to compare the accuracy of white light, narrow band imaging (NBI), and Lugol to detect esophageal neoplasia in patients with a history of cured ESCC, in a prospective study. Thirty patients were prospectively included between June 2006 and June 2009. They all had a history of cured ESCC. Esophageal mucosa was examined first using white light, second NBI, and third after Lugol staining. Histology was obtained in all abnormalities detected by white light, NBI, and/or Lugol. Five neoplastic lesions in five different patients were identified at histology, four cancers, and one high-grade dysplasia. NBI and Lugol both detected all esophageal neoplastic lesions, whereas white light detected the four cancers but missed the high-grade dysplasia. In this feasibility study, NBI and Lugol both detected all identified esophageal neoplasia in very high-risk patients of ESCC. This result suggests that NBI could be used instead of Lugol to detect an esophageal neoplasia in patients with high risk of ESCC, but needs to be confirmed in a larger study.

[Assessment of adherence to Afssaps guidelines for the prescription of antifungals in pediatric hemato-oncology]. / Évaluation de l'adhésion au référentiel Afssaps sur les antifongiques, en hémato-oncologie pédiatrique.

OBJECTIVE: This study had for aim to identify factors limiting the implementation of clinical guidelines related to the use of expensive antifungal drugs in pediatric hemato-oncology. DESIGN: A retrospective study was conducted in a Lyon teaching hospital (France), from February to December 2008. The compliance of antifungal prescription to French guidelines was assessed. Audit findings were interpreted using both semi-directed interviews of six prescribers (qualitative approach) and statistical analysis of prescriptions (quantitative approach). RESULTS: Fifty antifungal prescriptions were studied. The compliance with clinical guidelines reached 66% (CI 95% 52-80%). The semi-directed interviews revealed that five issues may have influenced the adherence of prescribers with recommended practices: the guidelines, the molecule, the prescriber, the child, and practice settings. The statistical analysis did not reveal any link between the prescriber's activities or his department and the compliance with guidelines. A significant association was found between the documentation of infection and the non-conformity of antifungal prescriptions (p=0.02). CONCLUSIONS: This study, combining qualitative and quantitative assessments, addressed potential issues related to the implementation of guidelines in specific patient groups or to their adaptation in the context of pediatric hematology-oncology. Harmonization of practices related to the widespread use of antifungal associations is required.

Enhancing the absorption coefficient of a backed rigid frame porous layer by embedding circular periodic inclusions.

The acoustic properties of a porous sheet of medium static air flow resistivity (around 10,000 N m s(-4)), in which a periodic set of circular inclusions is embedded and which is backed by a rigid plate, are investigated. The inclusions and porous skeleton are assumed motionless. Such a structure behaves like a multi-component diffraction grating. Numerical results show that this structure presents a quasi-total (close to unity) absorption peak below the quarter-wavelength resonance of the porous sheet in absence of inclusions. This result is explained by the excitation of a complex trapped mode. When more than one inclusion per spatial period is considered, additional quasi-total absorption peaks are observed. The numerical results, as calculated with the help of the mode-matching method described in this paper, agree with those calculated using a finite element method.

Burden of hip fracture on inpatient care: a before and after population-based study.

SUMMARY: We estimated the excess hospital expenditure attributable to osteoporotic hip fracture (HF) within a population of 6,019 patients. Post-fracture excess of hospital days was 23.1, including 22.7 days in rehabilitation care. HF might result from a patient's pre-fracture poor health status rather than predispose to a worsening of such pre-existing conditions. INTRODUCTION: Hip fracture represents a large burden on hospital services. It is unclear whether the post-fracture expenditure is linked to a worsening of pre-fracture comorbid conditions. We estimated the excess hospital expenditure attributable to osteoporotic HF following the initial hospitalization for acute care (index stay). METHODS: We identified 6,019 patients (> or = 50 years) who experienced HF in 2005 and compared their hospitalizations 1 year before and 1 year after the index stay. Excess expenditure was estimated by subtracting the utilization of hospital days or costs (Euros 2005) before the index stay from those after the index stay. Factors associated with hospitalization during the pre-fracture and post-fracture years were identified using multivariate logistic regressions. RESULTS: Beside the index stay, post-fracture excess of hospital days was 23.1 (95% Confidence Interval (CI) [21.8-24.3]), including 22.7 days (95% CI [21.7-23.7]) in rehabilitation care and 0.3 days (95% CI [0-0.9]) in acute care. Estimated excess cost per patient was 5,986 (95% CI [5,638-6,335]) after the index stay, including 5,673 (95% CI [5,419-5,928]) in rehabilitation care. Male and elderly patients were at higher risk to be hospitalized in acute care during the year preceding and succeeding HF. CONCLUSIONS: Osteoporotic HF represents a pronounced excess expenditure in hospital, which is mostly linked to rehabilitation care. Considering that utilization of inpatient acute care was quite similar before and after the index stay, HF might result from a patient's pre-fracture poor health status, rather than predispose to a worsening of such pre-existing conditions.

Hospital volume influences the choice of operation for thyroid cancer.

BACKGROUND: Many authors advocate total or near-total thyroidectomy for thyroid carcinoma. This study examined the relationship between hospital volume of thyroidectomies and choice of bilateral thyroidectomy for thyroid carcinoma. METHODS: Data were extracted from the administrative databases of all hospital discharge abstracts in the Rhône-Alpes area of France. The study population included inpatient stays from 1999 to 2004 with a diagnosis of thyroid disease (benign or malignant) and a procedural code for thyroid surgery. Multivariable logistic regression analyses were performed to determine factors associated with the extent of surgery (unilateral versus bilateral) for thyroid carcinoma. RESULTS: A total of 20 140 thyroidectomies were identified, including 4006 procedures for cancer. Compared with hospitals performing a high volume of procedures for all thyroid diseases (at least 100 annually), the risk of a unilateral procedure for thyroid cancer increased by 2.46 (95 per cent confidence interval 1.63 to 3.71) in low-volume hospitals (fewer than ten operations per year) and by 1.56 (1.27 to 1.92) in medium-volume centres (ten to 99 per year). CONCLUSION: There is a significant relationship between hospital volume and the decision to perform bilateral surgery for thyroid carcinoma. Thyroid cancer surgery should be performed by experienced surgical teams in high-volume centres.