Heterogeneous impacts of mobility restrictions on air quality in the State of Sao Paulo during the COVID-19 pandemic

Air quality in the State of Sao Paulo was evaluated during the first general State plan of mobility restrictions due to the COVID-19 pandemic (24th March to May 31, 2020). Nitrogen dioxide (NO₂), ozone (O₃), particulate matter PM₁₀ and PM_2.5 and sulphur dioxide (SO₂) concentrations were assessed in cities of the Sao Paulo State with a monitoring station and compared to historical data. Linear regression models were built to investigate the relationship between the isolation of the population - determined using mobile phone monitoring data - and the concentration of each pollutant during the studied period. Although the reduction of pollutants such as NO₂, SO₂ and PM_2.5 is very clear, the economic and climatic characteristics of each region were decisive in the general behaviour of O₃ and PM₁₀. It was not possible to establish a correlation between the pollutants and the isolation index, partly due to the lack of data, partly due to the compliance of the population to those measurements, which was variable over time. Another important limitation factor was the absence of data related to the pollutants of interest in many of the stations. However, the isolation measures carried out in the State opened the opportunity to individually assess the air quality measurements in each of the stations, enabling an understanding that will allow in the future the design of air quality policies together with local sanitary policies.

High levels of metals/metalloids in blood and urine of residents living in the area affected by the dam failing in Barra Longa, District, Brazil: A preliminary human biomonitoring study

Fundão mining tailings dam in Mariana District has collapsed in 2015 and caused the biggest environmental disaster in Brazil. Barra Longa District had its urban area invaded by toxic sludge and its population was extensively exposed to it. Blood and urine samples were collected from 11 residents, focused on investigating the presence of metals at the end of an exploratory health study in 507 inhabitants in 2016. Results have shown increased levels of aluminum, arsenic, cadmium, cooper, lead, manganese and nickel, and zinc defficiency in their body, as well as clinical outcomes.

Nosocomial Infection With Cephalosporin-ResistantKlebsiella pneumoniaeIs Not Associated With Increased Mortality

Objective.

To evaluate whether resistance to third-generation cephalosporins and/or aztreonam was associated with a higher mortality rate among patients with nosocomialKlebsiella pneumoniaeinfections.

Design.

Retrospective cohort study.

Setting.

Tertiary care university hospital.

Methods.

A total of 143 patients with nosocomial infections due toK. pneumoniaewere evaluated. Death within 21 days after diagnosis of infection was the outcome. Demographic data, invasive procedures, presence and severity of underlying conditions, infection diagnosis, anatomic site of isolation, and treatment of infection, as well as resistance to third-generation cephalosporins and/or aztreonam, were evaluated for association with the outcome.

Results.

The mortality associated with nosocomialK. pneumoniaeinfections was 22% in our study. Drug resistance was found in isolates from 48% of case patients. Multivariate analysis demonstrated that the severity of the patient's underlying condition (odds ratio, 12.50;P<.01) and isolation of the microorganism from the blood or from another usually sterile site (odds ratio, 2.94;P= .03) were associated with death. On the other hand, the presence of resistance to cephalosporins and/or aztreonam did not affect mortality, and the use of inadequate treatment was not significantly associated with increased mortality. When only the severe cases of infection were analyzed, the results were unchanged.

Conclusions.

Resistance to cephalosporins and/or aztreonam did not affect mortality, and the use of inadequate treatment was not significantly associated with increased mortality. The reasons for this are not clear. It is possible that the severity of the underlying disease and the patient's condition have a larger role than theK. pneumoniaeinfection in determining the outcome, and initially inadequate treatment may not have an impact sufficient to cause irreversible damage, allowing treatment to be changed to an effective drug.

Clonal dissemination of VanA-type glycopeptide-resistant Enterococcus faecalis between hospitals of two cities located 100 km apart

Nosocomial dissemination of glycopeptide-resistant enterococci represents a major problem in hospitals worldwide. In Brazil, the dissemination among hospitals in the city of São Paulo of polyclonal DNA profiles was previously described for vancomycin-resistant Enterococcus faecium. We describe here the dissemination of VanA phenotype E. faecalis between two hospitals located in different cities in the State of São Paulo. The index outbreak occurred in a tertiary care university hospital (HCUSP) in the city of São Paulo and three years later a cluster caused by the same strain was recognized in two patients hospitalized in a private tertiary care hospital (CMC) located 100 km away in the interior of the state. From May to July 1999, 10 strains of vancomycin-resistant E. faecalis were isolated from 10 patients hospitalized in the HCUSP. The DNA genotyping using pulsed-field gel electrophoresis (PFGE) showed that all isolates were originated from the same clone, suggesting nosocomial dissemination. From May to July 2002, three strains of vancomycin-resistant E. faecalis were isolated from two patients hospitalized in CMC and both patients were colonized by the vancomycin-resistant Enterococcus in skin lesions. All isolates from CMC and HCUSP were highly resistant to vancomycin and teicoplanin. The three strains from CMC had minimum inhibitory concentration >256 micro g/ml for vancomycin, and 64 (CMC 1 and CMC 2) and 96 micro g/ml (CMC 3) for teicoplanin, characterizing a profile of VanA resistance to glycopeptides. All strains had the presence of the transposon Tn1546 detected by PCR and were closely related when typed by PFGE. The dissemination of the E. faecalis VanA phenotype among hospitals located in different cities is of great concern because E. faecalis commonly colonizes the gastrointestinal tract of patients and healthy persons for periods varying from weeks to years, which, together with the persistence of vancomycin-resistant Enterococcus in hospital rooms after standard cleaning procedures, increases the risk of the dissemination and reservoir of the bacteria.

[Therapy of postoperative arrhythmias (author's transl)]

Severe supraventricular and ventricular tachyarrhythmias occurred after surgery in 9 patients. Oxprenolol or pindolol were used as primary drugs in 8 cases. The effect of therapy was documented quantitatively by an arrhythmia computer with trendscription and alarm recording. Beta-receptor blockade was successful in 6 cases. On supraventricular tachycardia with Wolff-Parkinson-White syndrome was abolished by quinidine. Severe ventricular instability with fibrillation following myocardial infarction was temporarily suppressed by lidocaine. One fatal outcome was caused by severe illness. Although all patients were suffering from coronary artery and/or hypertensive heart disease with diminished cardiac reserve, no serious side effects were directly related to beta-receptor blockade. Therefore beta-receptor blocking drugs are recommended as drugs of first choice in the treatment of postoperative arrhythmias induced by sympathetic overstimulation. Dysrhythmias based on cellular pathology should be treated with conventional antiarrhythmic drugs alone or combined with beta-blockers.

[Postoperative cardiac arrhythmias (author's transl)]

13 male patients suffering from arteriosclerotic heart disease and/or arterial hypertension were monitored continuously before and after vascular surgical procedures using an arrhythmia computer. Heart rate, paroxysmal supraventricular tachycardias, ventricular extrasystoles, ventricular tachycardias, ventricular fibrillation and prematurity index (QnQe/QTn) were recorded numerically. Ventricular arrhythmias were detected as follows preoperatively in 12 patients, after operation in all patients, paired ventricular extrasystoles or episodes of ventricular tachycardia were found in 5 cases before and in 7 after operation, ventricular fibrillation in one case. The incidence of ventricular dysrhythmias increased significantly (p less than 0.05) early after operation, as did the heart rate during the observed postoperative period (p less than 0.001). The prematurity index dropped below 1.0 during the two days following operation. This differed significantly from the preoperative value (p less than 0.05). The incidence of ventricular extrasystoles was related to postoperative myocardial infarction and heart failure (p less than 0.01), which occurred in 6 cases, with a lethal outcome in three. Only occasionally controlled by trained staff in a normal surgical ward the "Servomed Dysrhythmiemonitor" yielded reliable numerical results during the main part of the monitored period. In two cases it led to immediate detection and rapid institution of treatment of severe tachyar rhythmias.

[Prophylactic effect of isosorbide dinitrate on postoperative cardiac complications (author's transl)]

Isosorbide dinitrate (ISD) was administered before, during and after 178 operations performed on 127 patients with arterial occlusive disease. Its influence on postoperative myocardial infarction, heart failure and mortality was tested by comparison with 188 operations performed on 140 patients with hypertension and/or old myocardial infarction receiving no ISD prophylaxis. Risk of cardiac complications was similar in both groups. Mortality in the ISD-treated group was significantly lowered as compared with the control group and was about half of the overall mortality in patients with arterial occlusive disease operated on at our hospital over the past 10 years. This difference depended partly on the influence of ISD on cardiac complications. Post-operative myocardial infarction during ISD prophylaxis occurred in 0.6% of cases as compared with 3.7% in the control group (p less than 0.05), whilst the respective values for postoperative heart failure were 5.7% and 18.2% (p less than 0.001). Both complications are related to absolute or relative hypoxia during the post-operative stress period. ISD is effective by lowering cardiac preload and afterload and thereby diminishing myocardial oxygen demand. ISD is the drug of choice for surgical patients since it provides a steady and long-lasting effect after sublingual absorption. ISD prophylaxis during the perioperative period is indicated in cases with coronary artery disease and with increased cardiac preload or afterload.

[Risk factors and pathogenesis of postoperative cardiac decompensation (author's transl)]

In 214 patients with healed myocardial infarction an assessment was made of the prognostic value of risk factors relating to early postoperative cardiac decompensation which occurred in 50 cases. A significant influence was shown by age (greater than or equal to 75 years), pre-existing heart failure and load insufficiency, hypertension (greater than or equal to 180/95 mm Hg), advanced arteriosclerosis with cerebrovascular and renovascular symptoms, infections with fever or septicemia, emergency operations, lang-lasting surgery, decrease in blood pressure during operations (greater than or equal to 70 mm Hg systolic) and postoperative anemia (less than or equal to 3.5 millions erythrocytes/cmm). The postoperative cardiac failure took a lethal course in 60%. Pathogenetically, the discrepancy between O2-requirement and O2-supply in the previously damaged myocardium is of essential importance during the postoperative stress period.

[Risk factors in postoperative myocardial infarction]

Myocardial infarction after major surgery occurred 25 times in 214 patients who had previously sustained infarcts. Analysis of data obtained before, during and after 335 operations in these patients revealed the following pathogenetic factors in the infarction: (1) The patient with the highest coronary risk had arterial hypertension of at least 160/95 mmHg and advanced arteriosclerosis combined with coronary arterial, peripheral arterial, cerebrovascular, and renovascular disease. (2) Myocardial necrosis occurred when oxygen supply was reduced, as evidenced from a fall in systolic blood pressure to 70 mmHg or less during operation or anaemia (RBC smaller than or equal to 3,5 times 10-6/mul) early after operation. (3) Risk of infarction was highest during the early postoperative stress period with elevated plasma catecholamine levels and thus an increased myocardial oxygen demand.