Assessment of the Smartpill, a Wireless Sensor, as a Measurement Tool for Intra-Abdominal Pressure (IAP).

Background: The SmartPill, a multisensor ingestible capsule, is marketed for intestinal motility disorders. It includes a pressure sensor, which could be used to study intra-abdominal pressure (IAP) variations. However, the validation data are lacking for this use. Material and Methods: An experimental study was conducted on anesthetized pigs with stepwise variations of IAP (from 0 to 15 mmHg by 3 mmHg steps) generated by laparoscopic insufflation. A SmartPill, inserted by endoscopy, provided intragastric pressure data. These data were compensated to take into account the intrabdominal temperature. They were compared to the pressure recorded by intragastric (IG) and intraperitoneal (IP) wired sensors by statistical Spearman and Bland-Altmann analysis. Results: More than 4500 pressure values for each sensor were generated on two animals. The IG pressure values obtained with the SmartPill were correlated with the IG pressure values obtained with the wired sensor (respectively, Spearman ρ coefficients 0.90 ± 0.08 and 0.72 ± 0.25; bias of -28 ± -0.3 mmHg and -29.2 ± 0.5 mmHg for pigs 1 and 2). The intragastric SmartPill values were also correlated with the IAP measured intra-peritoneally (respectively, Spearman ρ coefficients 0.49 ± 0.18 and 0.57 ± 0.30; bias of -29 ± 1 mmHg and -31 ± 0.7 mmHg for pigs 1 and 2). Conclusions: The SmartPill is a wireless and painless sensor that appears to correctly monitor IAP variations.

Semiautomatic quantification of abdominal wall muscles deformations based on dynamic MRI image registration.

Quantitative analysis of abdominal organs motion and deformation is crucial to better understand biomechanical alterations undermining respiratory, digestive or perineal pathophysiology. In particular, biomechanical characterization of the antero-lateral abdominal wall is central in the diagnosis of abdominal muscle deficiency. Here, we present a dedicated semiautomatic dynamic MRI postprocessing method enabling the quantification of spatial and temporal deformations of the antero-lateral abdominal wall muscles. Ten healthy participants were imaged during a controlled breathing session at the L3-L4 disc level using real-time dynamic MRI at 3 T. A coarse feature-tracking step allowed the selection of the inhalation cycle of maximum abdominal excursion. Over this image series, the described method combines (1) a supervised 2D+t segmentation procedure of the abdominal wall muscles, (2) the quantification of muscle deformations based on masks registration, and (3) the mapping of deformations within muscle subzones leveraging a dedicated automatic parcellation. The supervised 2D+t segmentation (1) provided an accurate segmentation of the abdominal wall muscles throughout maximum inhalation with a 0.95 ± 0.03 Dice similarity coefficient (DSC) value and a 2.3 ± 0.7 mm Hausdorff distance value while requiring only manual segmentation of 20% of the data. The robustness of the deformation quantification (2) was indicated by high indices of correspondence between the registered source mask and the target mask (0.98 ± 0.01 DSC value and 2.1 ± 1.5 mm Hausdorff distance value). Parcellation (3) enabled the distinction of muscle substructures that are anatomically relevant but could not be distinguished based on image contrast. The present genuine postprocessing method provides a quantitative analytical frame that could be used in further studies for a better understanding of abdominal wall deformations in physiological and pathological situations.

Trauma-related mortality of patients with severe psychiatric disorders: population-based study from the French national hospital database.

BACKGROUND: Most research on mortality in people with severe psychiatric disorders has focused on natural causes of death. Little is known about trauma-related mortality, although bipolar disorder and schizophrenia have been associated with increased risk of self-administered injury and road accidents. AIMS: To determine if 30-day in-patient mortality from traumatic injury was increased in people with bipolar disorder and schizophrenia compared with those without psychiatric disorders. METHOD: A French national 2016 database of 144 058 hospital admissions for trauma was explored. Patients with bipolar disorder and schizophrenia were selected and matched with mentally healthy controls in a 1:3 ratio according to age, gender, social deprivation and region of residence. We collected the following data: sociodemographic characteristics, comorbidities, trauma severity characteristics and trauma circumstances. Study outcome was 30-day in-patient mortality. RESULTS: The study included 1059 people with bipolar disorder, 1575 people with schizophrenia and their respective controls (n = 3177 and n = 4725). The 30-day mortality was 5.7% in bipolar disorder, 5.1% in schizophrenia and 3.3 and 3.8% in the controls, respectively. Only bipolar disorder was associated with increased mortality in univariate analyses. This association remained significant after adjustment for sociodemographic characteristics and comorbidities but not after adjustment for trauma severity. Self-administered injuries were associated with increased mortality independent of the presence of a psychiatric diagnosis. CONCLUSIONS: Patients with bipolar disorder are at higher risk of 30-day mortality, probably through increased trauma severity. A self-administered injury is predictive of a poor survival prognosis regardless of psychiatric diagnosis.

30-Day Postoperative Morbidity of Emergency Surgery for Obstructive Right- and Left-Sided Colon Cancer in Obese Patients: A Multicenter Cohort Study of the French Surgical Association.

BACKGROUND: Emergency surgery impairs postoperative outcomes in colorectal cancer patients. No study has assessed the relationship between obesity and postoperative results in this setting. OBJECTIVE: To compare the results of emergency surgery for obstructive colon cancer (OCC) in an obese patient population with those in overweight and normal weight patient groups. METHODS: From 2000 to 2015, patients undergoing emergency surgery for OCC in French surgical centers members of the French National Surgical Association were included. Three groups were defined: normal weight (body mass index [BMI] < 25.0 kg/m2), overweight (BMI 25.0-29.9 kg/m2), and obese (BMI ≥30.0 kg/m2). RESULTS: Of 1,241 patients, 329 (26.5%) were overweight and 143 (11.5%) were obese. Obese patients had significantly higher American society of anesthesiologists score, more cardiovascular comorbidity and more hemodynamic instability at presentation. Overall postoperative mortality and morbidity were 8 and 51%, respectively, with no difference between the 3 groups. For obese patients with left-sided OCC, stoma-related complications were significantly increased (8 vs. 5 vs. 15%, p = 0.02). CONCLUSION: Compared with lower BMI patients, obese patients with OCC had a more severe presentation at admission but similar surgical management. Obesity did not increase 30-day postoperative morbidity except stoma-related complications for those with left-sided OCC.

Abdominal wall morphometric variability based on computed tomography: Influence of age, gender, and body mass index.

INTRODUCTION: Ventral hernia surgery does not usually account for the individuality of the abdominal wall anatomy. This could be both because medical imaging is rarely performed before surgery and because data on abdominal wall variability are limited. The objective of the present study was to perform an exhaustive morphometric analysis of abdominal wall components based on computed tomography (CT) scans. MATERIALS AND METHODS: A retrospective study was performed on 120 abdominopelvic CT scans of clinically normal adults aged 18-86 years equally divided between women and men and into four age groups. Each abdominal wall muscle was evaluated in terms of area, thickness, shape ratio, fat infiltration, and aponeuroses width. The influence of age, gender, and body mass index (BMI) was investigated, as well as muscular asymmetry. RESULTS: The abdominal wall muscle area represented 8.5 ± 2.5% of the abdominal area. The internal oblique muscle had the largest area, the rectus abdominis was the thickest, the transversus abdominis was the narrowest and had the smallest area. The width of the linea alba was 20.3 ± 12.0 mm. The evolution of the abdominal wall with age was quantified, as well as the large differences between the sexes and BMI groups, resulting in strong correlations and highlighting the specific pattern of the transversus abdominis. The asymmetry of the left and right muscle areas oscillated around 17%. CONCLUSIONS: The various components of the abdominal wall have been precisely described. Knowledge of their variability could be used to enhance the planning of ventral hernia surgery or to develop numerical modeling of the abdominal wall.

Endoscopic treatment of fistulas after sleeve gastrectomy: a comparison of internal drainage versus closure.

BACKGROUND AND AIMS: Fistulas after sleeve gastrectomy are major adverse events of bariatric surgery. The endoscopic management strategy evolved from closure to internal drainage after 2013. The main objective of our study was to evaluate and compare these different approaches. METHODS: This retrospective study included all patients treated for fistulas after sleeve gastrectomy in a referral center. Closure management was defined as initial treatment that used a covered metal stent and/or endoclips. Internal drainage management was defined as initial treatment by nasocystic drain and/or a double-pigtail stent. RESULTS: A total of 100 patients (women N = 78, mean [± standard deviation {SD}] age 42 ± 12 years) were included between 2007 and 2015. The mean (± SD) delay between sleeve gastrectomy and the first endoscopy was 82 ± 125 days. The overall success of endoscopic treatment was 86% within 6 ± 27 months. Two patients died. The primary success of internal drainage and closure management occurred in 19 of 22 (86%) and 49 of 77 (63%) patients, respectively. Among patients in failure for closure management, 22 had secondary internal drainage (18 being successful). Success of initial management was significantly higher for internal drainage (P = .043). Factors associated with failure of closure management were in multivariable analysis: collection >5 cm (P = .013). Factors associated with a time >6 months for achieving leakage closure were in multivariable analysis: reoperation before endoscopy (P = .044) and purulent flow at endoscopy (P = .043). CONCLUSIONS: Endoscopic management of fistulas after sleeve gastrectomy was successful in 86% of cases. In cases of collections >5 cm, internal drainage should be proposed first. Surgical reintervention before endoscopy delays treatment success.

Lean body weight is the best scale for venous thromboprophylaxis algorithm in severely obese patients undergoing bariatric surgery.

Severely obese patients undergoing bariatric surgery (BS) are at increased risk for venous thromboembolism (VTE). How standard low molecular weight heparin (LMWH) regimen should be adapted to provide both sufficient efficacy and safety in this setting is unclear. We aimed to compare the influence of four body size descriptors (BSD) on peak anti-Xa levels in BS obese patients receiving LMWH fixed doses to identify which one had the greatest impact. One hundred and thirteen BS obese patients [median body mass index (BMI), 43.3 kg/m2 (IQR, 40.6-48.7 kg/m2)] receiving subcutaneous dalteparin 5000 IU twice daily were included in this prospective monocenter study. Peak steady-state anti-Xa levels were measured peri-operatively following thromboprophylaxis initiation. Only 48% of patients achieved target anti-Xa levels (0.2-0.5 IU/ml). In univariate analysis, age, gender, total body-weight (TBW), lean body-weight (LBW), ideal body-weight (IBW), BMI and estimated glomerural filtration rate (eGFR) were associated with anti-Xa levels. The strongest negative association was observed with LBW (r = -0.56, p < .0001). Receiver operating characteristic curves indicated that among BSD, LBW (cut-off >55.8 kg) had the highest sensitivity (73%) and specificity (69%) to predict sub-prophylactic anti-Xa levels. In multivariate analysis, LBW and eGFR remained associated with anti-Xa levels (ß = -0.47 ±â€¯0.08, p < .0001 and ß = -0.19 ±â€¯0.08; p = .02, respectively). In BS morbidly obese patients receiving LMWH for thromboprophylaxis after BS, LBW and eGFR are the main determinants of anti-Xa level, and could be proposed in LMWH-based thromboprophylaxis dosing algorithms. The efficacy of a LBW-scale based dosing algorithm for optimal VTE prevention deserves further prospective randomized trials.

Do height and weight affect the feasibility of single-incision laparoscopic cholecystectomy?

BACKGROUND: Laparoscopic cholecystectomy is the gold standard for gallbladder removal and the most common laparoscopic procedure worldwide. Single-incision laparoscopic surgery has recently emerged as a less invasive potential alternative to conventional three- or four-port laparoscopy. However, the feasibility of single-incision laparoscopic cholecystectomy (SILC) remains unclear, and there are no rigorous criteria in the literature. Identifying patients at risk of failure of this new technique is essential. The aim of our study was to determine risk factors that may predict failure of the procedure. METHODS: From May 2010 to March 2012, 110 consecutive patients underwent SILC and were reviewed retrospectively. The main feasibility criterion was the procedure failure rate, defined as addition of supplementary port(s) and prolonged (>60 min) operative time. The factors evaluated were age, gender, height, weight, body mass index, previous abdominal surgery, indication for surgery and gallbladder suspension. RESULTS: There was conversion in 16 patients (14.5%), and the operative time exceeded 60 min for 20 patients (30.9%). Univariate analysis showed a significant independent association between additional port requirement and each of weight as a continuous value, weight ≥80 kg, BMI >26.5 kg/m(2) and height >172 cm. Univariate analysis also showed a significant independent association between prolonged operative duration (>60 min) and each of height and weight as continuous values, height >172 cm and previous abdominal surgery. In the multivariate analysis, only weight remained independently associated with additional port requirement, and height remained independently associated with prolonged operative duration. CONCLUSION: Preoperative identification of the factors increasing the risk of conversion may assist surgeons in making decisions concerning the management of patients, including appropriate use of SILC.

Three-dimensional variability of the mesentery and the superior mesenteric artery: application to virtual trauma modeling.

INTRODUCTION: Trauma is a major cause of death worldwide, mainly affecting a young male population. Blunt trauma of the abdomen can cause a trauma of the mesentery in 5 % of cases. Rapid decelerations and injuries by seat belts are the most common pathophysiological mechanisms. Three-dimensional anatomical scanning of the mesentery and gastrointestinal tract is the first essential step in modeling abdominal trauma in an attempt to understand the pathophysiology of mesenteric lesions and to improve the safety features of vehicles. OBJECTIVE OF THE STUDY: To analyze the individual variability of the mesentery and the superior mesenteric artery (SMA) from medical imaging and to develop a three-dimensional customizable finite element model. MATERIALS AND METHODS: In this retrospective study, one hundred abdominopelvic injected CT scans were analyzed from healthy patients. The evaluation criteria of the mesentery were its volume (total and the distribution of adipose tissue/non adipose tissue), the length of the SMA and the distance between duodenojejunal angle (DJA) and the ileocecal junction (ICJ). The variability of these measures has been studied by demographic (age and gender) and morphologic (height evaluated by the T11-L4 distance, the waist circumference and the thickness of the subcutaneous adipose tissue). RESULTS: Mean mesenteric volume was 644 cm(3) (ranges from 89 to 1,869 cm(3)), and the mean length of the SMA was 224.9 mm (ranges from 138.4 to 312.3). There was a statistically significant association between waist circumference and the total volume of the mesentery, its fat component and non fat component (p < 0.001). Waist circumference was the only morphological parameter associated with the length of the superior mesenteric artery and the length of the DJA to ICJ (p < 0.001). Subcutaneous adipose tissue and female sex were statistically associated with total mesentery volume (respectively, p = 0.005 and p = 0.001). Age was an independent predictor of the increased volume of the mesentery and the length of the SMA. The height of the subject changes the length of the SMA (p = 0.001). CONCLUSION: The assessment of the mesenteric variability highlighted three factors associated with its size and length: age, sex, and waist circumference. These parameters have to be taken into account to personalize numerical model in the area of virtual trauma.

Unravelling the mechanics of gastric tissue: A comparison of constitutive models, damage probability and microstructural insights.

With the increasing prevalence of obesity worldwide, bariatric surgery is becoming increasingly common. However, the mechanic of the gastric wall related to bariatric surgery complications remains to be investigated. This study aims to understand mechanical behaviour of stomach by developing advanced material laws for gastric tissue incorporating microstructure. A multi-scale characterisation of the porcine stomach wall was performed in the fundus and corpus anatomical regions and in circumferential and longitudinal orientations The protocol included uniaxial tensile testing until damage, survival analysis to provide damage probability, comparison of phenomenological (Fung and Ogden order 1, 2 and 3) and structural (Holzapfel fibre-reinforced) computational models fitted to the experimental data, and quantitative analysis of elastin and collagen fibre structure from histological slides. All constitutive models fitted the experimental data well (r2 > 0.988 and RSME<3.8 kPa). Longitudinal and circumferential elastic modulus in quasi linear phase were respectively 1.75 ± 1.2 MPa, 0.76 ± 0.35 MPa for fundus, and 2.30 ± 0.66 MPa, 1.36 ± 0.89 MPa for corpus, highlighting significant differences between orientations in fundus and corpus, with an overall softer fundus in the circumferential direction. Microstructure analysis illustrated collagen and elastin fibre orientation, dispersion and density. As microstructure appears to play an important role in stomach biomechanics, model incorporating fibre structure such as Holzapfel fibre-reinforced model, seem best suited to describe the material behaviour of the stomach wall. Future research should complement these findings with an expanded sample set in human models.