Sarcopenia in Cirrhosis: Fallout on Liver Transplantation.

BACKGROUND: Liver transplantation (LT) is a game changer in cirrhosis. Poor muscle mass defined as sarcopenia may potentially upset the LT scoreboard. AIM: To assess the prevalence and impact of sarcopenia on the intraoperative and early postoperative outcomes in Indian patients undergoing LT. METHODS: Pre LT, single-slice routine computed tomography images at L3 vertebra of 115 LT recipients were analyzed, to obtain cross-sectional area of six skeletal muscles normalized for height in m2 - skeletal muscle index (SMI; cm2/m2). SMI< 52.4 in males and <38.5 in females was called sarcopenia. The intraoperative, postoperative outcome parameters and 90-day mortality were compared between sarcopenics and nonsarcopenics. RESULTS: Sarcopenia was found in 47.8% of patients [M (90.4%); age, 46.3 ± 10; BMI, 24.5 ± 4.3 kg/m2; child A:B:C = 1%:22%:77%; MELD, 20.6 ± 6.3; etiology alcohol: nonalchohol = 53%:47%; Charlson Comorbidity Index (CCI) > 3:≤3 = 56.5%:43.5%]. Sarcopenics vs. Nonsarcopenics; early postoperative complications: [sepsis, 49(89%) vs. 33(55%), P = 0.001; neurologic complications, 16(29.6%) vs. 5(8.8%), P = 0.040; Clavien-Dindo Classification ≥3-24 (43.6%):15 (25.4%),P = 0.041; ancillary parameters (days), duration of ventilation [median (range)] 1.5(1-3) vs. 1 (1-2), P = 0.021; intensive care unit (ICU) stay 12 (8-16) vs. 10 (8-12), P = 0.024; time to ambulation 9 (7-11) vs. 6 (5-7), P = 0.001; drain removal 18.7 ± 7.3 vs. 14.4 ± 6.2, P = 0.001; need for tracheostomy 5 (9%) vs. 0 (%), P = 0.017; preoperative prevalence of acute kidney injury, comorbidities and requirement for dialysis, intraoperative blood loss & inotropic support were significantly higher in sarcopenics. Ninety-day mortality was comparable between sarcopenics 5 (9.09%) and nonsarcopenics 4 (6.6%) P = 0.63. SMI (OR: 0.83; 95% CI: 0.71-0.97, P = 0.016; Acute on chronic liver failure (ACLF) presentation 12.5 (1.65-95.2), P = 0.015 and intraoperative blood loss 3.74 (0.96-14.6), P = 0.046 were predictors of 90-day mortality. CONCLUSION: Almost 50% of LT recipients had sarcopenia, who had a higher incidence of postoperative sepsis, neurological complications, longer ICU stay and ventilatory support. Low SMI, ACLF presentation, and intraoperative blood loss were the independent predictors of early mortality.

Association of thrombocytopenia with outcome following adult living donor liver transplantation.

This study aimed to evaluate the association of postoperative thrombocytopenia with outcome following adult living donor liver transplantation (LDLT) for end-stage liver disease (ESLD). It was a prospective study of 120 consecutive adult LDLT from September 2012 to May 2015. Preoperative platelet counts (PLTs) and postoperative PLTs were recorded at regular intervals till 3 months after LDLT. Univariate and multivariate analyses were performed. The median pretransplant PLT was 61 × 10(9) /l. The lowest median PLT after LDLT was observed on POD 3. Patients were stratified into low platelet group (n = 83) with PLT <30 × 10(9) /l and high platelet group (n = 37) with PLT ≥30 × 10(9) /l. Patients with PLT <30 × 10(9) /l had statistically significant higher grade III/IV complication (P = 0.001), early graft dysfunction (P = 0.01), sepsis (P = 0.001), and prolonged ascites drainage (P = 0.002). On multivariate analysis, PLT<30 × 10(9) /l was identified as an independent risk factor for grade III/IV complications (P = 0.005). Overall, patients survival was significantly different between two groups (P = 0.04), but this predictive value was lost in patients who survived more than 90 days (P = 0.37). Postoperative PLT of <30 × 10(9) /l was a strong predictor of major postoperative complications and is associated with early graft dysfunction, prolonged ascites drainage, and sepsis. The perioperative mortality rate was high in the thrombocytopenia group.

Impact of small-scale geometric roughness on wetting behavior.

We examine the extent to which small-scale geometric substrate roughness influences the wetting behavior of fluids at solid surfaces. Molecular simulation is used to construct roughness wetting diagrams wherein the progression of the contact angle is traced from the Cassie to Wenzel to impregnation regime with increasing substrate strength for a collection of systems with rectangularly shaped grooves. We focus on the evolution of these diagrams as the length scale of the substrate features approaches the size of a fluid molecule. When considering a series of wetting diagrams for substrates with fixed shape and variable feature periodicity, we find that the diagrams progressively shift away from a common curve as the substrate features become smaller than approximately 10 fluid diameters. It is at this length scale that the macroscopic models of Cassie and Wenzel become unreliable. Deviations from the macroscopic models are attributed to the manner in which the effective substrate-fluid interaction strength evolves with periodicity and the important role that confinement effects play for substrates with small periodicities.

Understanding wetting of immiscible liquids near a solid surface using molecular simulation.

We introduce Monte Carlo simulation methods for determining interfacial properties of fluids that exhibit bulk liquid-liquid immiscibility. An interface-potential-based approach, in which the interfacial properties of a system are related to the surface excess free energy of a thin fluid film in contact with a surface, is utilized to deduce the wetting characteristics of these systems. We present a framework for implementing this general method within both the grand canonical and semigrand isobaric-isothermal ensembles. Tracking the evolution of interfacial properties along various thermodynamic paths is also examined. This task is accomplished by implementing variants of the expanded ensemble technique, which enables one to obtain components of the interface potential along a path of interest. We also discuss how these concepts are employed to calculate bulk liquid-liquid coexistence properties in an efficient manner. The computational strategies introduced here are applied to three model Lennard-Jones systems. For each system, we compile the evolution of the liquid-liquid surface tension and contact angle with temperature or pressure. For one of the model systems we compare our results with literature data. We also examine how interfacial properties evolve upon variation of the relative affinity of the fluid components for the substrate. Overall, we find that the approach pursued here is generally applicable and provides an efficient and precise means to calculate the bulk and interfacial properties of fluids that exhibit liquid-liquid immiscibility.

Monte Carlo simulation strategies to compute interfacial and bulk properties of binary fluid mixtures.

We introduce Monte Carlo simulation methods for determining interfacial properties of binary fluid mixtures. The interface potential approach, in which the interfacial properties of a system are related to the surface excess free energy of a thin fluid film in contact with a surface, is utilized to deduce the wetting characteristics of a fluid mixture. The strategy described here provides an effective means to obtain the evolution of interfacial properties with the chemical composition of the fluid. This task is accomplished by implementing an activity fraction expanded ensemble technique, which allows one to obtain elements of the interface potential as a function of composition. We also show how this technique can be utilized to calculate bulk coexistence properties of fluid mixtures in an efficient manner. The computational strategies introduced here are applied to three model systems. One includes an argon-methane fluid mixture that is known to display simple behavior in the bulk. The second fluid model contains a size asymmetric mixture that exhibits azeotropy. The third model fluid is the well-studied size symmetric mixture that displays liquid-liquid-vapor phase coexistence. The techniques outlined here are used to compile the composition dependence of spreading and drying coefficients, liquid-vapor surface tension, and contact angle for these systems. We also compare our surface tension results with values estimated from predictive-style models that provide the surface tension of a fluid mixture in terms of pure component properties. Overall, we find that the general approach pursued here provides an efficient and precise means to calculate the bulk and wetting properties of fluid mixtures.

Comparison of a Fistulectomy and a Fistulotomy with Marsupialization in the Management of a Simple Anal Fistula: A Randomized, Controlled Pilot Trial

PURPOSE: This randomized clinical trial was conducted to compare a fistulectomy and a fistulotomy with marsupialization in the management of a simple anal fistula. METHODS: Forty patients with simple anal fistula were randomized into two groups. Fistulous tracts were managed by using a fistulectomy (group A) while a fistulotomy with marsupialization was performed in group B. The primary outcome measure was wound healing time while secondary outcome measures were operating time, postoperative wound size, postoperative pain, wound infection, anal incontinence, recurrence and patient satisfaction. RESULTS: Postoperative wounds in group B healed earlier in comparison to group A wounds (4.85 +/- 1.39 weeks vs. 6.75 +/- 1.83 weeks, P = 0.035). No significant differences existed between the operating times (28.00 +/- 6.35 minutes vs. 28.20 +/- 6.57 minutes, P = 0.925) and visual analogue scale scores for postoperative pain on the first postoperative day (4.05 +/- 1.47 vs. 4.50 +/- 1.32, P = 0.221) for the two groups. Postoperative wounds were larger in group A than in group B (2.07 +/- 0.1.90 cm2 vs. 1.23 +/- 0.87 cm2), however this difference did not reach statistical significance (P = 0.192). Wound discharge was observed for a significantly longer duration in group A than in group B (4.10 +/- 1.91 weeks vs. 2.75 +/- 1.71 weeks, P = 0.035). There were no differences in social and sexual activities after surgery between the patients of the two groups. No patient developed anal incontinence or recurrence during the follow-up period of twelve weeks. CONCLUSION: In comparison to a fistulectomy, a fistulotomy with marsupialization results in faster healing and a shorter duration of wound discharge without increasing the operating time.

Monte Carlo simulation methods for computing the wetting and drying properties of model systems.

We introduce general Monte Carlo simulation methods for determining the wetting and drying properties of model systems. We employ an interface-potential-based approach in which the interfacial properties of a system are related to the surface excess free energy of a thin fluid film in contact with a surface. Two versions of this approach are explored: a "spreading" method focused on the growth of a thin liquid film from a surface in a mother vapor and a "drying" method focused on the growth of a thin vapor film from a surface in a mother liquid. The former provides a direct measure of the spreading coefficient while the latter provides an analogous drying coefficient. When coupled with an independent measure of the liquid-vapor surface tension, these coefficients enable one to compute the contact angle. We also show how one can combine information gathered from application of the spreading and drying methods at a common state point to obtain direct measures of the contact angle and liquid-vapor surface tension. The computational strategies introduced here are applied to two model systems. One includes a monatomic Lennard-Jones fluid that interacts with a structureless substrate via a long-ranged substrate potential. The second model contains a monatomic Lennard-Jones fluid that interacts with an atomistically detailed substrate via a short-ranged potential. Expanded ensemble techniques are coupled with the interface potential approach to compile the temperature- and substrate strength-dependence of various interfacial properties for these systems. Overall, we find that the approach pursued here provides an efficient and precise means to calculate the wetting and drying properties of model systems.

Monte Carlo simulation strategies for computing the wetting properties of fluids at geometrically rough surfaces.

We introduce Monte Carlo simulation methods for determining the wetting properties of model systems at geometrically rough interfaces. The techniques described here enable one to calculate the macroscopic contact angle of a droplet that organizes in one of the three wetting states commonly observed for fluids at geometrically rough surfaces: the Cassie, Wenzel, and impregnation states. We adopt an interface potential approach in which the wetting properties of a system are related to the surface density dependence of the surface excess free energy of a thin liquid film in contact with the substrate. We first describe challenges and inefficiencies encountered when implementing a direct version of this approach to compute the properties of fluids at rough surfaces. Next, we detail a series of convenient thermodynamic paths that enable one to obtain free energy information at relevant surface densities over a wide range of temperatures and substrate strengths in an efficient manner. We then show how this information is assembled to construct complete wetting diagrams at a temperature of interest. The strategy pursued within this work is general and is expected to be applicable to a wide range of molecular systems. To demonstrate the utility of the approach, we present results for a Lennard-Jones fluid in contact with a substrate containing rectangular-shaped grooves characterized by feature sizes of order ten fluid diameters. For this particular fluid-substrate combination, we find that the macroscopic theories of Cassie and Wenzel provide a reasonable description of simulation data.