[Ethical recommendations for a difficult decision-making in intensive care units due to the exceptional situation of crisis by the COVID-19 pandemia: A rapid review & consensus of experts]

Ante la situación excepcional de salud pública provocada por la pandemia por COVID-19, desde el grupo de ética de la Sociedad Española de Medicina Intensiva, Crítica y Unidades Coronarias (SEMICYUC) se ha promovido un trabajo de consenso con el objetivo de encontrar algunas respuestas desde la ética a la encrucijada entre el incremento de personas con necesidades de atención intensiva y la disponibilidad efectiva de medios.

En un periodo muy corto de tiempo se ha cambiado el marco de ejercicio de la medicina hacia un escenario de «medicina de catástrofe», con el consecuente cambio en los parámetros de toma de decisiones. En este contexto la asignación de recursos o la priorización de tratamiento pasan a ser elementos cruciales, y es importante contar con un marco de referencia ético para poder tomar las decisiones clínicas necesarias. Para ello, se ha realizado un proceso de revisión narrativa de la evidencia, seguida de un consenso de expertos no sistematizado, que ha tenido como resultado tanto la publicación de un documento de posicionamiento y recomendaciones de la propia SEMICYUC, como el consenso entre 18 sociedades científicas y 5 institutos/cátedras de bioética y cuidados paliativos de un documento marco de referencia de recomendaciones éticas generales en este contexto de crisis.

Society of pediatric liver transplantation: Current registry status 2011-2018

BACKGROUND

SPLIT was founded in 1995 in order to collect comprehensive prospective data on pediatric liver transplantation, including waiting list data, transplant, and early and late outcomes. Since 2011, data collection of the current registry has been refined to focus on prospective data and outcomes only after transplant to serve as a foundation for the future development of targeted clinical studies.

OBJECTIVE

To report the outcomes of the SPLIT registry from 2011 to 2018.

METHODS

This is a multicenter, cross-sectional analysis characterizing patients transplanted and enrolled in the SPLIT registry between 2011 and 2018. All patients, <18 years of age, received a first liver-only, a combined liver-kidney, or a combined liver-pancreas transplant during this study period.

RESULTS

A total of 1911 recipients from 39 participating centers in North America were registered. Indications included biliary atresia (38.5%), metabolic disease (19.1%), tumors (11.7%), and fulminant liver failure (11.5%). Greater than 50% of recipients were transplanted as either Status 1A/1B or with a MELD/PELD exception score. Incompatible transplants were performed in 4.1%. Kaplan-Meier estimates of 1-year patient and graft survival were 97.3% and 96.6%. First 30 days of surgical complications included reoperation (31.7%), hepatic artery thrombosis (6.3%), and portal vein thrombosis (3.2%). In the first 90 days, biliary tract complications were reported in 13.6%. Acute cellular rejection during first year was 34.7%. At 1 and 2 years of follow-up, 39.2% and 50.6% had normal liver tests on monotherapy (tacrolimus or sirolimus). Further surgical, survival, allograft function, and complications are detailed.

Cascaded interactions mediated by terahertz radiation

We investigate a regime of parametric amplification in which the pump and signal waves are spectrally separated by only a few hundreds of GHz frequency - therefore resulting in a sub-THz frequency idler wave. Operating in this regime we find an optical parametric amplifier (OPA) behavior which is highly dissimilar to conventional OPAs. In this regime, we observe multiple three-wave mixing processes occurring simultaneously which results in spectral cascading around the pump and signal wave. Via numerical simulations, we elucidate the processes at work and show that cascaded optical parametric amplification offers a pathway toward THz-wave generation beyond the Manly-Rowe limit and toward the generation of high-energy, sparse frequency-combs.

AXSIS: Exploring the frontiers in attosecond X-ray science, imaging and spectroscopy

X-ray crystallography is one of the main methods to determine atomic-resolution 3D images of the whole spectrum of molecules ranging from small inorganic clusters to large protein complexes consisting of hundred-thousands of atoms that constitute the macromolecular machinery of life. Life is not static, and unravelling the structure and dynamics of the most important reactions in chemistry and biology is essential to uncover their mechanism. Many of these reactions, including photosynthesis which drives our biosphere, are light induced and occur on ultrafast timescales. These have been studied with high time resolution primarily by optical spectroscopy, enabled by ultrafast laser technology, but they reduce the vast complexity of the process to a few reaction coordinates. In the AXSIS project at CFEL in Hamburg, funded by the European Research Council, we develop the new method of attosecond serial X-ray crystallography and spectroscopy, to give a full description of ultrafast processes atomically resolved in real space and on the electronic energy landscape, from co-measurement of X-ray and optical spectra, and X-ray diffraction. This technique will revolutionize our understanding of structure and function at the atomic and molecular level and thereby unravel fundamental processes in chemistry and biology like energy conversion processes. For that purpose, we develop a compact, fully coherent, THz-driven atto-second X-ray source based on coherent inverse Compton scattering off a free-electron crystal, to outrun radiation damage effects due to the necessary high X-ray irradiance required to acquire diffraction signals. This highly synergistic project starts from a completely clean slate rather than conforming to the specifications of a large free-electron laser (FEL) user facility, to optimize the entire instrumentation towards fundamental measurements of the mechanism of light absorption and excitation energy transfer. A multidisciplinary team formed by laser-, accelerator,- X-ray scientists as well as spectroscopists and biochemists optimizes X-ray pulse parameters, in tandem with sample delivery, crystal size, and advanced X-ray detectors. Ultimately, the new capability, attosecond serial X-ray crystallography and spectroscopy, will be applied to one of the most important problems in structural biology, which is to elucidate the dynamics of light reactions, electron transfer and protein structure in photosynthesis.

Diastolic dysfunction in the critically ill patient

Left ventricular diastolic dysfunction is a common finding in critically ill patients. It is characterized by a progressive deterioration of the relaxation and the compliance of the left ventricle. Two-dimensional and Doppler echocardiography is a cornerstone in its diagnosis. Acute pulmonary edema associated with hypertensive crisis is the most frequent presentation of diastolic dysfunction critically ill patients. Myocardial ischemia, sepsis and weaning failure from mechanical ventilation also may be associated with diastolic dysfunction. The treatment is based on the reduction of pulmonary congestion and left ventricular filling pressures. Some studies have found a prognostic role of diastolic dysfunction in some diseases such as sepsis. The present review aims to analyze thoroughly the echocardiographic diagnosis and the most frequent scenarios in critically ill patients in whom diastolic dysfunction plays a key role.

Use of B-type natriuretic peptides to detect the existence and severity of diastolic dysfunction in non-cardiac critically ill patients: a pilot study

BACKGROUND

This observational study was designed to evaluate and compare the usefulness of BNP and NT-proBNP concentrations to detect the existence and severity of left ventricular diastolic dysfunction (LVDD) in critically ill patients.

METHODS

A prospective, observational study in a university hospital. The sample included 86 consecutive adult patients. Based on echocardiography data, LVDD were classified into normal, impaired relaxation, pseudonormal or restrictive patterns. Patients were classified according to whether filling pressures were elevated or non-elevated in the echocardiography. Sampling for natriuretic peptides was performed immediately before echocardiography.

RESULTS

Fifty patients showed LVDD. The most frequently observed pattern was impaired relaxation (N.=35), followed by the restrictive (N.=9) and the pseudonormal (N.=6) patterns. BNP concentrations in restrictive and pseudonormal patterns were higher than in normal and impaired relaxation patterns, while NT-proBNP only showed differences between normal and pseudonormal or restrictive patterns. Cut-off values using ROC curve analyses to detect LVDD were 125 ng/L for BNP and 390 ng/L NT-proBNP. BNP and NT-proBNP concentrations were higher in the 15 patients with restrictive and pseudonormal patterns, suggesting elevated filling pressures. Cut-off values using ROC curve analyses to detect echocardiography signs of elevated filling pressures were 254 ng/L for BNP and 968 for NT-proBNP. Both natriopeptides performed in a similar way to detect LVDD and elevated filling pressures.

CONCLUSION

Both BNP and NT-proBNP are useful screening tools to detect the presence of advanced degrees of LVDD, and especially to rule out elevated filling pressures.

[Hemodynamic monitoring in the critically patient. Recomendations of the Cardiological Intensive Care and CPR Working Group of the Spanish Society of Intensive Care and Coronary Units]

Hemodynamic monitoring offers valuable information on cardiovascular performance in the critically ill, and has become a fundamental tool in the diagnostic approach and in the therapy guidance of those patients presenting with tissue hypoperfusion. From introduction of the pulmonary artery catheter to the latest less invasive technologies, hemodynamic monitoring has been surrounded by many questions regarding its usefulness and its ultimate impact on patient prognosis. The Cardiological Intensive Care and CPR Working Group (GTCIC-RCP) of the Spanish Society of Intensive Care and Coronary Units (SEMICYUC) has recently impulsed the development of an updating series in hemodynamic monitoring. Now, a final series of recommendations are presented in order to analyze essential issues in hemodynamics, with the purpose of becoming a useful tool for residents and critical care practitioners involved in the daily management of critically ill patients.

[Evaluation of contractility and postloading in the intensive care unit]

Cardiovascular failure is a common disorder in critical care medicine. When admitted to the ICU, patients with hemodynamic deterioration should be examined rapidly to correctly assess the main determinants of cardiovascular function (preload, afterload and contractility). This review examines the assessment of contractility and afterload involving the combined use of several hemodynamic monitors, which allows different approaches to the same problem, with a view to improving the efficiency of management and treatment in critically ill patients.

Multicity HIV seroprevalence in street youth, Ukraine

We conducted the first systematic, community-based, multicity assessment outside the USA of HIV seroprevalence, risk factors and linkage into clinical services among 929 street youth. After city-wide mapping, we used time-location sampling and randomly selected 74 venues in Odesa, Kyiv and Donetsk, Ukraine. Rapid HIV testing with post-test counselling was offered to all eligible youths aged 15-24 years. Overall, 18.4% (95% confidence interval 16.2-20.2) were HIV positive and 85% had previously unknown status. Rates were identical by sex. Subgroups with highest rates included orphans (26%), youths with histories of exchanging sex (35%), sexually transmitted infections (STIs) (37%), injection drug use (IDU) (42%) and needle sharing (49%). Independent predictors, similar across age groups and city, included being orphaned, time on the street, history of anal sex, STIs, exchanging sex, any drug use, IDU and needle sharing. Two-thirds (68%) of HIV-positive youths were linked to services. This high-risk population has many immediate needs.

Success of medical therapy in a rare case of cecal ameboma

Colitis caused by Entamoeba histolytica (EH) is prevalent in developing countries. Clinical presentation ranges from mild diarrhoea episodes to dysentery and liver abscess. Ameboma, a complication caused by EH invasion of the intestinal wall, is a rare presentation of amebiasis, occurring approximately in 1.5% of cases. Because of its insidious and variable clinical presentation only few cases are diagnosed previous to surgical intervention. We report a 52 years old Mexican-mestizo female, presenting with a pain-less right lower quadrant abdominal mass and diagnosed of cecal ameboma prior to surgery by colonoscopy and histopathologic examination. The present case highlights the importance of early diagnosis and medical therapy with antiparasitic drugs in order to avoid complications that could lead these patients to unnecessary surgical management.

[Predicting very early rebleeding after acute variceal bleeding based in classification and regression tree analysis (CRTA).]

BACKGROUND

Variceal bleeding (VB) is the main cause of death among cirrhotic patients. About 30-50% of early rebleeding is encountered few days after the acute episode of VB. It is necessary to stratify patients with high risk of very early rebleeding (VER) for more aggressive therapies. However, there are few and incompletely understood prognostic models for this purpose.

AIMS

To determine the risk factors associated with VER after an acute VB. Assessment and comparison of a novel prognostic model generated by Classification and Regression Tree Analysis (CART) with classic-used models (MELD and Child-Pugh [CP]).

PATIENTS AND METHODS

Sixty consecutive cirrhotic patients with acute variceal bleeding. CART analysis, MELD and Child-Pugh scores were performed at admission. Receiver operating characteristic (ROC) curves were constructed to evaluate the predictive performance of the models.

RESULTS

Very early rebleeding rate was 13%. Variables associated with VER were: serum albumin (p = 0.027), creatinine (p = 0.021) and transfused blood units in the first 24 hrs (p = 0.05). The area under the ROC for MELD, CHILD-Pugh and CART were 0.46, 0.50 and 0.82, respectively. The value of cut analyzed by CART for the significant variables were: 1) Albumin 2.85 mg/dL, 2) Packed red cells 2 units and 3) Creatinine 1.65 mg/dL the ABC-ROC.

CONCLUSION

Serum albumin, creatinine and number of transfused blood units were associated with VER. A simple CART algorithm combining these variables allows an accurate predictive assessment of VER after acute variceal bleeding. Key words: cirrhosis, variceal bleeding, esophageal varices, prognosis, portal hypertension.

Effect of the menstrual cycle in ethanol pharmacokinetics

Differences in ethanol pharmacokinetics within the menstrual cycle have previously been reported and attributed to variations in body composition, hormonal influences and gastric emptying. To establish the role of the menstrual cycle in ethanol pharmacokinetics associated with changes in body composition, ethanol blood concentrations were measured in nine healthy women during the midfollicular (P1, days 8-10) and midluteal (P2, days 22-24) phases of the menstrual cycle after a postprandial oral ethanol dose (0.3 g kg(-1)). Total body water was assessed by dual-energy x-ray densitometry (DEXA) on both occasions. Median total body water did not vary during either phase of the menstrual cycle (P1 = 54.54%, P2 = 54.66%; P = 0.9296). Median area under the ethanol concentration-time curve (AUC) was lower during P1 (215.33 mg.h dl(-1)) than during P2 (231.33 mg.h dl(-1))(P = 0.8253). No significant differences were found on ethanol pharmacokinetics in either phase of the menstrual cycle.

[Use of polyethylene glycol in the treatment of puerperal constipation]

We evaluated the efficiency of polyethylene glycol at low dosage as a treatment for constipation in the puerperium. A prospective, open label and control study was performed in 225 puerpery patients. We observed a 94.7% of study group patients and a 10.7% of a control group patients had a evacuation in the first 48 hours, (p < 0.01). Decreased consistency of the stools was seen in the PEG group (74.3%). According to our findings, low doses of PEG were useful and safe as a treatment for constipation in the puerperium, without side effects.

Development of highly specific monoclonal antibodies for the diagnosis of Vibrio cholerae 01

We report here the development of two monoclonal antibodies, termed 5G8 and 5C12, belonging to the IgM and IgG1 class, respectively, suitable for the identification of Vibrio cholerae 01 in clinical and environmental samples. The specificities of the monoclonals were evaluated by ELISA and indirect immunofluorescent microscopy of microorganisms normally present in stool samples and with two bacterial panels. One panel included 72 potentially antigenically related bacterial strains and the second panel included 20 pathogenic bacterial strains involved in diarrhea cases. The results of these extensive analyses indicate that monoclonal antibodies 5G8 and 5C12 are highly specific and suitable for the clinical diagnosis of Vibrio cholerae 01 in human stool samples by indirect immunofluorescent microscopy. Although the antigenic sites recognized by these antibodies were not identified in this study, the observation of Western blot patterns suggested that 5G8 and 5C12 monoclonal antibodies bind to LPS epitopes, a good structural marker for the detection of V. cholerae 01 because it is present in all bacterial cell walls.

[Clinical characteristics and endoscopic-histologic correlation in patients with chronic non-specific ulcerative colitis]

Our objective was to evaluate prospectively, objectively and in a systematic way the evaluation of patients with Ulcerative Colitis (UC) with moderate activity. We studied 14 outpatients, who were evaluated for an experimental therapeutic protocol. The activity of the disease was established using clinical, endoscopic and histologic parameters. The Kappa Index (K) was used for statistical analysis. The average number of bowel movements was 4/day; rectal bleeding and urgency were found in 100%, diarrhea in 78% and abdominal pain in 64%. The severity of rectal bleeding and urgency was graded II or III in 92% and 78% respectively. The correlation between endoscopy and histology (K = 0.55), and between clinical and endoscopy (K = 0.45) was moderate. There was no correlation between clinical and histological parameters.

IN CONCLUSION

the variability of symptoms impairs the clinical evaluation as the unique method to determine the activity of UC and to take therapeutical decisions is necessary to perform a endoscopic/histology correlation.

[Prevalence of antinuclear antibodies in primary biliary cirrhosis, with negative antimitochondrial antibodies]

Recently it has been described in the literature a subpopulation of PBC patients with negative AMA that might represent patients with ANA positive autoimmune cholangitis. We review 25 cases of PBC (23 females) with AMA negative. Our aim was to determine the frequency of ANA(+) in this group. We studied serum transaminases, total bilirubin, AMA and ANA by indirect immunofluorescence considering positive dilutions of 1:40. All patients had elevated alkaline phosphatase (641 +/- 389 U/l). Total bilirubin was below 2.5 in 59%. Thirteen patients had esophageal varices. The histologic stage was I-II in eleven and III-IV in 14 cases. Fourteen patients (56%) has ANA(+) (dilution 1:40), 44% had lower dilutions. We confirm the presence of a subpopulation of PBC AMA negative, ANA positive patients and the observations of different and diverse immune alterations in PBC patients.

[Bacterial isolation in infants hospitalized for acute diarrhea]

Bacteria were investigated in stools of 156 children under two years of age admitted to the pediatric wards of a general hospital at the western metropolitan area of Santiago, Chile, because of acute diarrhea with only one stool sample. A known pathogenic agent was isolated from 115 cases (73.7%), this being a bacteria in 87/115 (75.6%). Most prevalent microorganisms were Enteropathogenic Escherichia coli (EPEC). (65.5%), specially serogroups 0111, 0119 and 055, Enterotoxigenic Escherichia coli (ETEC) (18.4%), Campylobacter yeyuni (13.8%), Salmonellae (9.2%) and Shigellae (6.9%). Invasive Escherichia coli (EIEC) and Aeromonas hydrophila were observed in only one case. Yersinia enterocolitica was not isolated. Age was under one year in 92% of patients and 83% were normally or slightly under nourished. Fecal leucocytes were abnormally increased (greater than 5 per high power field) in 41.4% of positive bacterial isolates, in 83% of children with Shigellae, in 50% of those with EPEC and Salmonellae and in 25% of the Campylobacter yeyuni group.

Acidifying enemas (lactitol and lactose) vs. nonacidifying enemas (tap water) to treat acute portal-systemic encephalopathy: a double-blind, randomized clinical trial

A double-blind, controlled trial to study the efficacy of acidifying enemas of lactitol, a new galactoside-sorbitol disaccharide, and lactose vs. nonacidifying tap-water enemas was performed in 45 episodes of acute portal-systemic encephalopathy. At the time of randomization, all patients had encephalopathy of at least Grade 2+ severity, delay in the performance of number connection tests and hyperammonemia. A sequential analysis was performed which revealed after the inclusion of the first 20 patients, a significant failure of the nonacidifying enemas as compared to the lactitol enemas (p less than 0.004). The tap-water enema group was, therefore, suspended but the rest of the study continued after rerandomization for lactose and lactitol groups. A favorable response to treatment was obtained in 19 (86%) of the patients receiving lactitol enemas and in 14 (78%) of those receiving lactose enemas. A similar significant improvement in portal-systemic encephalopathy parameters and index was observed after both treatments. Both types of acidifying enemas induced a significant pH decrease in stool (p less than 0.05). These data suggest that acidifying agents like lactose and lactitol are effective and superior to tap-water enemas for the treatment of acute nitrogenous portal-systemic encephalopathy.