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Introduction: In an effort of gaining a better understanding of the lens mechanics, ex vivo lenses samples are often used. Yet, ex vivo tissue might undergo important postmortem changes depending on the unavoidable preservation method employed. The purpose of this study was to assess how various storage conditions and the removal of the lens capsule affect the mechanical properties of ex vivo porcine lens samples., Methods: A total of 81 freshly enucleated porcine eyes were obtained and divided into six groups and preserved differently. In the first three groups, the lens within the intact eye was preserved for 24 h by: (i) freezing at -80°C (n = 12), (ii) freezing at -20°C (n = 12), and (iii) refrigeration at +8°C (n = 12). In the remaining groups, the lenses were immediately extracted and treated as follows: (iv) kept intact, no storage (n = 12), (v) decapsulated, no storage (n = 21), and (vi) immersed in Minimum Essential Medium (MEM) at +8°C (n = 12) for 24 h. Frozen lenses were thawed at room temperature. Each lens was compressed between two glass lamella and subjected, first to a period of relaxation during which the compression force was recorded and second to an oscillating micro-compression while the deformation was recorded with a total of 256 subsequent B-scans via optical coherence tomography. The corresponding axial strain was retrieved via phase-sensitive image processing and subsequently used as input for an inverse finite element analysis (iFEA) to retrieve the visco-hyperelastic material properties of the lenses., Results: After freezing at temperatures of -80°C and -20°C, the cortical strains increased by 14% ( p = 0.01) and 34% ( p < 0.001), and the nuclear strains decreased by 17% ( p = 0.014) and 36% ( p < 0.001), compared to the lenses tested immediately after postmortem, respectively. According to iFEA, this resulted from an increased ratio of the nuclear: cortical E-modulus (4.06 and 7.06) in -80°C and -20°C frozen lenses compared to fresh lenses (3.3). Decapsulation had the largest effect on the material constant C 10 , showing an increase both in the nucleus and cortex. Preservation of the intact eye in the refrigerator induced the least mechanical alterations in the lens, compared to the intact fresh condition., Discussion: Combining iFEA with optical coherence elastography allowed us to identify important changes in the lens mechanics induced after different preserving ex vivo methods., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Tahsini, Gil and Kling.)

Background: Bile duct injury rates for laparoscopic cholecystectomy (LC) remain higher than during open cholecystectomy. The "culture of safety" concept is based on demonstrating the critical view of safety (CVS) and/or correctly interpreting intraoperative cholangiography (IOC). However, the CVS may not always be achievable due to difficult anatomy or pathology. Safety may be enhanced if surgeons assess difficulties objectively, recognise instances where a CVS is unachievable and be familiar with recovery strategies., Aims and Methods: A prospective study was conducted to evaluate the achievability of the CVS during all consecutive LC performed over four years. The primary aim was to study the association between the inability to obtain the CVS and an objective measure of operative difficulty. The secondary aim was to identify preoperative and operative predictors indicating the use of alternate strategies to complete the operation safely., Results: The study included 1060 consecutive LC. The median age was 53 years, male to female ratio was 1:2.1 and 54.9% were emergency admissions. CVS was obtained in 84.2%, the majority being difficulty grade I or II (70.7%). Displaying the CVS failed in 167 LC (15.8%): including 55.6% of all difficulty grade IV LC and 92.3% of difficulty grade V. There were no biliary injuries or conversions., Conclusion: All three components of the critical view of safety could not be demonstrated in one out of 6 consecutive laparoscopic cholecystectomies. Preoperative factors and operative difficulty grading can predict cases where the CVS may not be achievable. Adapting instrument selection and alternate dissection strategies would then need to be considered., (© 2020. The Author(s).)

Background: To evaluate the laparoscopic management of Mirizzi syndrome, seldom diagnosed preoperatively causing difficulty when performing cholecystectomy and increasing complication risks., Methods: Analysis of a prospective single-surgeon database of 5700 laparoscopic cholecystectomies found 58 Mirizzi syndrome cases. They were managed with an intention to treat during the index admission according to protocol of single-session management of bile duct stones., Results: 38/58 patients were females (65.5%). The median age was 55 years. 53 cases were emergency admissions. 34 cases (58.6%) only had ultrasound scanning. Operative difficulty was Grade IV in 34 cases (58.6%) and Grade V in 20 (34.5%) (Nassar Scale). There were 33 Mirizzi Type IA, 7 Type IB, 16 Type II and one each of Type III and Type IV. Bile duct exploration was performed in 94.8% through choledochotomy/ transfistula in 58.6% or transcystic in 36.2%. Four cases required conversion to open. Postoperative morbidity occurred in 29%. Two 30-day mortalities occurred from pneumonia in two elderly patients who were late referrals., Conclusion: Although the utilization of the laparoscopic approach in managing bile duct stones is not currently widely practiced it was safer in this series than in reported series of open surgery in Mirizzi Syndrome. The optimal approach to Mirizzi Type II is via cholecystocholedochal fistula to explore the bile duct then drain with T-tube through the fistula. It is unnecessary to perform bilioenteric bypass in majority of cases, reducing the morbidity and mortality.

Background: The cystic lymph node (CLN) represents an anatomic safety marker and a surrogate marker of technique during laparoscopic cholecystectomy (LC). We aim to demonstrate the value of CLN in comparison to the critical view of safety (CVS) and study the effects of increasing difficulty on the 2 approaches., Methods: A prospective study of consecutive LC was conducted. Patient demographics, type of admission, clinical presentation, operative difficulty grade, visualization of CLN, identification of CVS, operative time, and complications were recorded and analyzed., Results: Of 393 LCs, half of the admissions were emergencies. Thirty-four percent had obstructive jaundice or acute cholecystitis. The CLN was visually identified in 81.7% with a small difference between operative difficulty grades 1 to 3 versus 4 to 5. Although CVS was unachievable in 62 patients, 43 (69.4%) still had an identifiable CLN. The median operating time was 68 minutes with 1 mortality but no conversions or intraoperative complications., Conclusions: Identifying the CLN during LC could compliment the CVS in avoiding major ductal injury. Dissecting lateral to the CLN to commence the process of displaying the cystic pedicle structures may be a strategy in safely achieving the CVS. During the more difficult LC where displaying the CVS is impossible, the CLN may be the key anatomic landmark., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: To evaluate the clinical characteristics, prevalence and factors associated with delirium in critical patients from 5 to 14 years of age., Design: An analytical, cross-sectional observational study was made. Delirium was assessed with the Pediatric-Confusion Assessment Method for the Intensive Care Unit (pCAM-ICU) and motor classification was established with the Delirium Rating Scale Revised-98., Setting: A pediatric Intensive Care Unit., Patients: All those admitted over a one-year period were assessed during the first 24-72h, or when possible in deeply sedated patients., Exclusion Criteria: Patients in stupor or coma, with severe communication difficulty, subjected to deep sedation throughout admission, and those with denied consent., Results: Twenty-nine of the 156 assessed patients suffered delirium (18.6%) and 55.2% were hypoactive. The neurocognitive alterations evaluated by the pCAM-ICU were similar in the three motor groups. Intellectual disability (OR=17.54; 95%CI: 3.23-95.19), mechanical ventilation (OR=18.80; 95%CI: 4.29-82.28), liver failure (OR=54.88; 95%CI: 4.27-705.33), neurological disease (OR=4.41; 95%CI: 1.23-15.83), anticholinergic drug use (OR=3.23; 95%CI: 1.02-10.26), different psychotropic agents (OR=4.88; 95%CI: 1.42-16.73) and tachycardia (OR=4.74; 95%CI: 1.21-18.51) were associated to delirium according to the logistic regression analysis., Conclusion: The frequency of delirium and hypoactivity was high. It is therefore necessary to routinely evaluate patients with standardized instruments. All patients presented with important neurocognitive alterations. Several factors related with the physiopathology of delirium were associated to the diagnosis; some of them are modifiable through the rationalization of medical care., (Copyright © 2018 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.)

Objectives: To describe the prevalence and characteristics of delirium during the initial evaluation of critically ill patients aged 5-14 years., Method/design: This is a cross-sectional descriptive study in a critical care unit. For six months, all patients were evaluated within the first 24-72 hours or when sedation permitted the use of the paediatric confusion assessment method for the intensive care unit (PCAM-ICU) and the Delirium Rating Scale-Revised-98 items #7 and #8 to determine motor type. We report the characteristics of PCAM-ICU delirium (at least three of the required items scored positive) and of subthreshold score cases (two positive items)., Results: Of 77 admissions, 15 (19.5%) had delirium, and 11 (14.2%) were subthreshold. A total of 53.3% of delirium and 45.5% of subthreshold cases were hypoactive. The prevalence of delirium and subthreshold PCAM-ICU was 83.3% and 16.7% in mechanically ventilated children. The most frequent combination of PCAM-ICU alterations in subthreshold cases was acute onset-fluctuation with altered alertness. The main nursing diagnoses were related to reduced cellular respiration., Conclusions: Delirium is common in critically ill children. It is necessary to assess whether certain nursing diagnoses imply an increase in delirium. Longitudinal studies of subthreshold PCAM-ICU cases are needed to understand their importance better., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Sickle cell disease (SCD) is one of the most common inherited diseases in the world and the patients present notorious clinical heterogeneity. It is known that patients with SCD present activation of the blood coagulation and fibrinolytic systems, especially during vaso-occlusive crises, but also during the steady state of the disease. We determined if the presence of the factor V gene G1691A mutation (factor V Leiden), the prothrombin gene G20210A variant, and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism may be risk factors for vascular complications in individuals with SCD. We studied 53 patients with SCD (60% being women), 29 with SS (sickle cell anemia; 28 years, range: 13-52 years) and 24 with SC (sickle-hemoglobin C disease; 38.5 years, range: 17-72 years) hemoglobinopathy. Factor V Leiden, MTHFR C677T polymorphism, and prothrombin G20210A variant were identified by PCR followed by further digestion of the PCR product with specific endonucleases. The following vascular complications were recorded: stroke, retinopathy, acute thoracic syndrome, and X-ray-documented avascular necrosis. Only one patient was heterozygous for factor V Leiden (1.8%) and there was no prothrombin G20210A variant. MTHFR 677TT polymorphism was detected in 1 patient (1.8%) and the heterozygous form 677TC was observed in 18 patients (34%, 9 with SS and 9 with SC disease), a prevalence similar to that reported by others. No association was detected between the presence of the MTHFR 677T allele and other genetic modulation factors, such as alpha-thalassemia, beta-globin gene haplotype and fetal hemoglobin. The presence of the MTHFR 677T allele was associated with the occurrence of vascular complications in SCD, although this association was not significant when each complication was considered separately. In conclusion, MTHFR C677T polymorphism might be a risk factor for vascular complications in SCD.