Noninvasive ventilation for severely acidotic patients in respiratory intermediate care units : Precision medicine in intermediate care units.

BACKGROUND: Severe acidosis can cause noninvasive ventilation (NIV) failure in chronic obstructive pulmonary disease (COPD) patients with acute hypercapnic respiratory failure (AHRF). NIV is therefore contraindicated outside of intensive care units (ICUs) in these patients. Less is known about NIV failure in patients with acute cardiogenic pulmonary edema (ACPE) and obesity hypoventilation syndrome (OHS). Therefore, the objective of the present study was to compare NIV failure rates between patients with severe and non-severe acidosis admitted to a respiratory intermediate care unit (RICU) with AHRF resulting from ACPE, COPD or OHS. METHODS: We prospectively included acidotic patients admitted to seven RICUs, where they were provided NIV as an initial ventilatory support measure. The clinical characteristics, pH evolutions, hospitalization or RICU stay durations and NIV failure rates were compared between patients with a pH ≥ 7.25 and a pH < 7.25. Logistic regression analysis was performed to determine the independent risk factors contributing to NIV failure. RESULTS: We included 969 patients (240 with ACPE, 540 with COPD and 189 with OHS). The baseline rates of severe acidosis were similar among the groups (45 % in the ACPE group, 41 % in the COPD group, and 38 % in the OHS group). Most of the patients with severe acidosis had increased disease severity compared with those with non-severe acidosis: the APACHE II scores were 21 ± 7.2 and 19 ± 5.8 for the ACPE patients (p < 0.05), 20 ± 5.7 and 19 ± 5.1 for the COPD patients (p < 0.01) and 18 ± 5.9 and 17 ± 4.7 for the OHS patients, respectively (NS). The patients with severe acidosis also exhibited worse arterial blood gas parameters: the PaCO2 levels were 87 ± 22 and 70 ± 15 in the ACPE patients (p < 0.001), 87 ± 21 and 76 ± 14 in the COPD patients, and 83 ± 17 and 74 ± 14 in the OHS patients (NS)., respectively Further, the patients with severe acidosis required a longer duration to achieve pH normalization than those with non-severe acidosis (patients with a normalized pH after the first hour: ACPE, 8 % vs. 43 %, p < 0.001; COPD, 11 % vs. 43 %, p < 0.001; and OHS, 13 % vs. 51 %, p < 0.001), and they had longer RICU stays, particularly those in the COPD group (ACPE, 4 ± 3.1 vs. 3.6 ± 2.5, NS; COPD, 5.1 ± 3 vs. 3.6 ± 2.1, p < 0.001; and OHS, 4.3 ± 2.6 vs. 3.7 ± 3.2, NS). The NIV failure rates were similar between the patients with severe and non-severe acidosis in the three disease groups (ACPE, 16 % vs. 12 %; COPD, 7 % vs. 7 %; and OHS, 11 % vs. 4 %). No common predictive factor for NIV failure was identified among the groups. CONCLUSIONS: ACPE, COPD and OHS patients with AHRF and severe acidosis (pH ≤ 7.25) who are admitted to an RICU can be successfully treated with NIV in these units. These results may be used to determine precise RICU admission criteria.

Iron-based catalysts for photocatalytic ozonation of some emerging pollutants of wastewater.

A synthetic secondary effluent containing an aqueous mixture of emerging contaminants (ECs) has been treated by photocatalytic ozonation using Fe(3+) or Fe3O4 as catalysts and black light lamps as the radiation source. For comparative purposes, ECs have also been treated by ultraviolet radiation (UVA radiation, black light) and ozonation (pH 3 and 7). With the exception of UVA radiation, O3-based processes lead to the total removal of ECs in the mixture. The time taken to achieve complete degradation depends on the oxidation process applied. Ozonation at pH 3 is the most effective technique. The addition of iron based catalysts results in a slight inhibition of the parent compounds degradation rate. However, a positive effect is experienced when measuring the total organic carbon (TOC) and the chemical oxygen demand (COD) removals. Photocatalytic oxidation in the presence of Fe(3+) leads to 81% and 88% of TOC and COD elimination, respectively, compared to only 23% and 29% of TOC and COD removals achieved by single ozonation. The RCT concept has been used to predict the theoretical ECs profiles in the homogeneous photocatalytic oxidation process studied. Treated wastewater effluent was toxic to Daphnia magna when Fe(3+) was used in photocatalytic ozonation. In this case, toxicity was likely due to the ferryoxalate formed in the process. Single ozonation significantly reduced the toxicity of the treated wastewater.

The levonorgestrel intrauterine system as an alternative to hysterectomy for the treatment of idiopathic menorrhagia.

AIM OF THE STUDY: Prospective, observational study to determine the percentage of hysterectomies cancelled after a year of treatment with levonorgestrel intrauterine system (LNG-IUS) among women diagnosed with idiopathic menorrhagia. MAIN FINDINGS: Eighty-two women with a mean age of 44.3 + or - 4.9 were enrolled. Throughout 1-year follow-up, progressive and significant reduction was observed in number of days of bleeding (8.9 + or - 4.0 vs. 5.0 + or - 5.4), number of sanitary measures (29.3 + or - 19.4 vs. 8.1 + or - 10.8) and percentage of patients having intense/very intense bleeding (98.8%vs. 6.4%). Duration of menstrual cycle significantly increased from 26.9 + or - 5.5 to 52.6 + or - 33.6 days. Significant improvement in overall health-related quality of life was achieved. Patient satisfaction was good/very good in 70.7%. Considering only women who attended 12-month visit satisfaction reached 91.2%. 75.6% of scheduled hysterectomies were cancelled. Adverse effects were recorded in less than 40% of patients with no significant differences between visits. Adverse effects led to premature discontinuation of treatment in seven cases. No serious adverse effects were encountered. INTERPRETATION OF RESULTS: LNG-IUS meets the effectiveness and tolerability criteria for being considered as a first choice treatment option for women with idiopathic menorrhagia. Its use may contribute to decrease the large number of hysterectomies scheduled in Spain.

Cryptococcal Infection of the Ventriculoperitoneal Shunt in an HIV-Infected Patient with an Excellent Immunovirologic Status.

BACKGROUND: Cryptococcus spp. is a rare cause of ventriculoperitoneal shunt (VPS) infection, with a variable clinical presentation. Diagnosis and treatment of this entity are challenging. CASE DESCRIPTION: A cryptococcal VPS infection occurred in a human immunodeficiency virus-infected patient with an excellent immunovirologic status, with an abdominal mass as the only clinical sign at presentation. Microbiologic diagnosis was confirmed when Cryptococcus neoformans was isolated in 4 cerebrospinal fluid samples on different days. The patient was treated with dual antifungal therapy (liposomal amphotericin B plus flucytosine). The VPS was initially externalized and then removed. At 12-month follow-up, the patient remained asymptomatic, and no replacement VPS was required. CONCLUSIONS: This is the first reported case of cryptococcal VPS infection in a patient with human immunodeficiency virus infection. Clinical outcome was excellent after dual antifungal therapy plus device withdrawal. Diagnosis and treatment of this entity remain a challenge for clinicians.

Fenton's oxidation of food processing wastewater components. Kinetic modeling of protocatechuic acid degradation.

The oxidation of protocatechuic acid (PA), a typical phenol-type compound present in food processing wastewater, has been carried out by means of Fenton's reagent. Both the H2O2 and Fe(II) initial concentrations increase the PA degradation rate. Temperature also enhances the PA conversion when raised from 283 to 313 K, a further increase to 323 K results in a lower PA removal. Increasing the PA initial concentration leads to a decrease of conversion values but an opposite effect in terms of removal rate. pH values in the range 3-4 resulted in the total inhibition of the oxidation process. Similar PA depletion rates were experienced regardless of the oxidation state of the catalyst (ferrous or ferric iron). Additionally, an attempt based on the classic Fenton's chemistry plus some other stages accounting for the Fe(II) regeneration from Fe(III) and the inefficient H2O2 decomposition was conducted to model the process.

Iron type catalysts for the ozonation of oxalic acid in water.

Two iron catalysts (Fe(III) and Fe2O3/Al2O3) have been used in the ozonation of oxalic acid in water at pH 2.5. Percentage removals of oxalic acid were 1.8%, 7% and 30% corresponding to the non-catalytic, homogeneous (Fe(III)) and heterogeneous (Fe2O3/Al2O3) catalytic ozonations, respectively. Catalytic oxalic acid ozonation leads in all cases to total mineralization. The mechanism of ozonation likely develops through formation of iron-oxalate complexes that further react with ozone without the participation of hydroxyl radicals. Because of the stringent acidic conditions, some metal leaching has been observed and quantified in the heterogeneous process. In the homogeneous catalysis, the kinetics was found to be first order with respect to ozone and oxalic acid while for the heterogeneous catalysis, the kinetic order depends on the concentration of ozone in the gas fed. Thus, at ozone concentrations lower than 30 mg L(-1), the heterogeneous ozonation is between first and zero order with respect to both ozone and oxalic acid while at higher ozone gas concentrations, the kinetics was found to be first and zero order with respect to oxalic acid and ozone, respectively. This kinetics is supported through an Eley-Rideal mechanism that involves a surface reaction between non-adsorbed ozone and adsorbed oxalic acid. Apparent activation energies of the homogeneous and heterogeneous catalytic ozonations were found to be 18.2 and 13.6 kcal mol(-1), respectively.

CNS infections in patients with temporary CSF shunts: Diagnostic, preventive and therapeutic approach / Infecciones del SNC en pacientes con drenaje ventricular externo: aproximación diagnóstica, preventiva y terapéutica

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Treatment of brines by combined Fenton's reagent-aerobic biodegradation. II. Process modelling.

Process modelling of the integrated Fenton's reagent-aerobic biodegradation system has been carried out by considering a detailed reaction mechanism for the chemical oxidation step and the generalised Monod equation for the biological treatment. Chemical oxygen demand has been contemplated as a pseudo-component for simulation purposes. The proposed mechanism takes into consideration different features experimentally found. Thus, the inefficient hydrogen peroxide decomposition into oxygen and water, the influence of temperature and other operating variables and the role of oxygen have been considered. The aerobic biodegradation of the effluent after the chemical oxidation has taken place has been well simulated by Monod equation with no inhibitory terms. Dependency on temperature has been correlated by Arrhenius expression.

Optimisation of Fenton's reagent usage as a pre-treatment for fermentation brines.

Pre-treatment of fermentation brines from green olives has been carried out by the Fe(II)/Fe(III)/H(2)O(2) system. Reagent concentration exerted a positive influence on chemical oxygen demand (COD) removal. Hydrogen peroxide uptake showed values in the range 0.3-1.6mol of COD eliminated per mol of H(2)O(2) consumed depending on operating conditions. The optimum working pH was found to be in the interval 2.0-3.5. Reaction temperature increased the COD degradation rate, although similar COD conversion values were obtained after 5h of treatment regardless of the value of this parameter. An analysis of the biodegradability of this type of effluent demonstrated the beneficial effect of the chemical pre-oxidation. According to the experimental results, it is suggested that there is an inhibitory effect of the wastewater due to its COD content and nature rather than attributable to the presence of high amounts of sodium chloride. Biodegradation efficiency increased as temperature was raised up to 30 degrees C. A further increase of this parameter up to 40 degrees C resulted in the death of the microorganisms.

Co-oxidation of p-hydroxybenzoic acid and atrazine by the Fenton's like system Fe(III)/H2O2.

The system Fe(III)/H2O2 has been used to oxidise an aqueous solution of p-hydroxybenzoic acid (pHB) in the absence of light. In the process, typical operating variables such as reagent concentration exert a positive influence in the pHB degradation rate. Optimum pH has been found to be around 3. The kinetic study suggests that the mechanism involved in this system differs to some extent from that reported for the classic Fenton's chemistry in pure water. Thus, formation of a complex Fe(III)-pHB seems to be a key step to initiate the oxidising mechanism. Stoichiometric measurements of the H2O2 consumption per mole of pHB degraded indicate a possible reduction of complexed Fe(III). Simultaneous oxidation of pHB (and other similar compounds such as tyrosol (Ty) or p-coumaric acid (pCu)) and atrazine have shown a synergistic effect of the first substance to remove the pesticide.