Have there been changes in the application of mechanical ventilation in relation to scientific evidence? A multicenter observational study in Mexico

OBJECTIVE

The main study objectives were to describe the practice of mechanical ventilation over an 18-year period in Mexico, and estimate changes in mortality among critical patients subjected to invasive mechanical ventilation (IMV).

DESIGN

A retrospective subanalysis of a prospective observational study conducted in 1998, 2004, 2010 and 2016 was carried out.

SETTING

Intensive Care Units (ICUs) in Mexico.

PARTICIPANTS

Adult patients consecutively enrolled in the ICU during one month and who underwent IMV for more than 12hours or noninvasive mechanical ventilation for more than one hour. Follow-up was performed up to a maximum of 28 days after inclusion.

INTERVENTIONS

None.

PRINCIPAL VARIABLES OF INTEREST

Age, sex, severity upon admission as estimated by SAPS II, parameters of daily arterial blood gases, treatment and complication variables, date and status at discharge from the ICU and from hospital.

RESULTS

A total of 959 patients were included in 81 ICUs. Tidal volume (vt) decreased significantly both in patients with acute respiratory distress syndrome (ARDS) criteria (estimated 8.5ml/kg b.w. in 1998 to 6ml/kg in 2016; P<0.001) and in patients without ARDS (estimated 9ml/kg b.w. in 1998 to 6ml/kg in 2016; P<0.001). The ventilatory protective strategy (defined as vt < 6ml/kg or < 8ml/kg and a plateau pressure < 30cmH₂O) was: 19% in 1998, 44% in 2004, 58% in 2010 and 75% in 2016 (P<0.001). The adjusted mortality rate in ICU over the 4 periods was: in 2004, odds ratio (OR) 1.05 (95% confidence interval, 95%CI: 0.73-1.72; P=0.764); in 2010, OR 1.68 (95%CI: 1.13-2.48; P=0.009); in 2016, OR 0.85 (95%CI: 0.60-1.20; P=0.368).

CONCLUSIONS

The clinical practice of IMV in Mexican ICUs has been modified over a period of 18 years. The most significant change is the ventilatory strategy based on low vt. These changes have not been associated with significant changes in mortality.

[Use of ready-to-use (RTU) products in home-based parenteral nutrition]

AIMS

To analyze the real possibility to use ready-to-use multichamber bags for total parenteral nutrition in adult patients on home parenteral nutrition.

METHODS

In June 2005 we studied the adult patients on home parenteral nutrition treatment controlled by the Nutritional Support Unit from an University Hospital. Demographic data, data relating to underlying disease state; infusion regimen and the necessity to modify it; body mass index, fat free mass index, and Karnofsky index evolution, and complications related to parenteral nutrition were assessed.

RESULTS

At the time of the study, 8 patients aged 48,9 +/- 17,7 years, were on home parenteral nutrition. The artificial nutrition treatment was administered due to short-bowel syndrome (2); motility disorders (2); suboclusion (2); rapid intestinal transit (1), and malabsorption syndrome (1). With the exception of the patient who started more recently the treatment, all the others needed changes in the parenteral nutrition treatment (number of days for week, or formula modification). In general, both the body mass index and the fat free mass index increased during the treatment. The Karnofsky index was maintained or increased. In relation to catheter-related infection, 4 episodes were observed (0.85/1.000 d of HPN).

CONCLUSIONS

Due to the effectiveness, safety and the diversity of multichamber bags available for parenteral nutrition, and the few complications observed in the patients studied, although more studied are necessary, our results suggest that we can use this commercial bags for adult patients on home parenteral nutrition.

[Hypophysio-adrenal axis in patients with chronic alcoholism]

OBJECTIVES

To study the situation of the hypophyso-adrenal axis in patients with chronic alcoholism.

METHOD

24 patients with chronic alcoholism admitted in our Institution with acute delirium were studied. Cortisol am and pm und (ACTH levels, along with hemogram with Wintrobe indexes, patelets number, triglicerides, total and HDL cholesterol, transaminases, alkaline phosphatase and gammaglutamyltranspeptidase were measured in serum.

RESULTS

The mean values of ACTH am were 41.2 pcg/ml (normal values 10-80 pcg/ml), of plasma cortisol am 22 mcg/ml (normal values 10-24 mcg/ml) and plasmo cortisol pm 12.3 mcg/ml (normal values 5-12 mcg/ml).

CONCLUSIONS

The amount of alcohol consumed by alcoholic patients ist not comparable to that used in animal models, which induced adrenal hyperfunction. Blood ACTH and cortisol levels are not useful as indirect markers of alcoholism. The Wintrobe indexes and serum gammaglutamyltranspeptidase levels are more useful for that purpose.

[Aetiology and bacterial resistance in urinary infections of outpatients]

BACKGROUND

Knowledge of the etiological agents of infections of the urinary tract and of the map of the antimicrobial sensitivity of each geographic zone is a practice recommended for improving the use of antibiotics and for facilitating the choice of empirical treatment. The aim of this study is to provide up-to-date information on the pathogen flora of outpatients urinary infections in our health area and their sensitivity to antimicrobials, based on the urinary cultivations carried out in the Microbiology laboratory of the Solchaga Outpatient Surgery during the last four years.

MATERIAL AND METHODS

Between 1996 and 1999, we carried out 92,816 urinary cultivations of outpatients. The urine specimens were sown on plaques with chocolate agar and MacKonkey agar with calibrated loop. The antibiogram was carried out using the Kirby-Bauer method.

RESULTS

The percentage of positive urinary cultivations was 17%. Gram-negative bacilli represented 88.9% of the isolations, Gram-positive cocci 11% and yeasts 0.1%. Escherichia coli was the most frequently isolated germ (71%). The sensitivity studies show that amoxycillin-clavulanic acid, first generation cephalosporins and fosfomycin maintain a sensitivity above 80%.

CONCLUSIONS

Up-to-date knowledge of the most common pathogen flora and their sensitivity to antimicrobials makes it possible for a more suitable selection to be made of the antibiotic treatment when the sensitivity pattern of the responsible germ is unavailable. In the light of the results we can conclude that amoxycillin-clavulanic acid, first generation cephalosporins and fosfomycin show a good activity in vitro, and should be considered as empirical treatments for infections of the urinary tract.

[Outbreak of multiresistant tuberculosis]

BASIS

Six cases of multiresistant tuberculosis diagnosed in the Hospital of Navarra in 1996 were studied.

MATERIAL AND METHODS

Sensitivity tests were carried out using the BACTEC 460TB system against four main anti-tuberculosis medicines: Isoniazid, Streptomycin, Rifampizin and Ethambutol. "Fingerprinting" techniques by means of RFLP with IS 6110 were used in the epidemiological study.

RESULTS

Four of the patients were also infected with HIV. All of them had a fatal short-term prognosis. These four showed resistance to the drugs under study; in three resistance was primary, and secondary in the fourth. The molecular study showed that three HIV+ patients had identical patterns of restriction fragment length polymorphism (RFLP). Two were brothers and nosocomial infection was demonstrated in the third. On the other hand, the RPLF pattern of these patients showed great similarity to that of one of the HIV- patients, which suggests a clone origin of the strains, no other epidemiological relationship being found. The RPLF pattern of the other HIV+ patient was identical to that of another of his strains, isolated 14 months before, with the first strain sensitive. The other two patients were HIV- women, and they evolved favourably. In one, who was diabetic, a multiresistant tuberculosis had been diagnosed 7 years before, remaining asymptomatic up until the present. The other involved a secondary resistance due to deficient treatment.

CONCLUSIONS

The appearance of multiresistant tuberculosis is a very serious problem amongst HIV+ patients, especially at a time when their life expectancy has improved considerably due to the new therapies. In HIV- patients, multiresistant tuberculosis has a better prognosis. Typification by means of restriction fragment length polymorphism is very useful in clarifying the origin of the cases.

[Tracheobronchial involvement in non-Hodgkin's lymphoma]

Tracheobronchial involvement in non-Hodgkin's lymphoma (NHL) has been little described. We present two patients with NHL and endobronchial involvement of different characteristics. In the first case diffuse involvement of the bronchial mucosa was observed in the context of a systemic NHL of 10 years' duration. In the second patient, endobronchial involvement consisted of a mass obstructing the trachea and the right main bronchus which was the first manifestation of lymphoma.

Clozapine: strong antiaggressive effects with minimal motor impairment

Clinical studies have shown clozapine to be effective in the treatment of schizophrenia and associated with an extremely low incidence of extrapiramidal side effects. Diverse studies indicate that clozapine is an atypical neuroleptic with a preferential activity on the mesolimbic structures and a lower affinity for striatal D2 receptors than the classical antipsychotics. The purpose of this study was to assess the behavioral properties of clozapine, especially its effects on aggressive and motor behaviors. Individually housed male mice of the OF1 strain were exposed to anosmic "standard opponents" 30 minutes after the last drug administration. One category of animals received a single IP dose of the compound (0.2, 0.5, 1 or 1.5 mg/kg). Another category received daily doses (0.5, 1 or 1.5 mg/kg) for 21 days. Encounters were videotaped and behavior evaluated using an ethologically based analysis. Clozapine, in the acute treatment condition, produced a significant decrease in "attack" and "threat" behaviors without "immobility" being significantly increased. These results suggest a rather specific antiaggressive action of the compound with little motor impairment. In the chronic administration, no significant change in aggressive behavior was observed which may be attributed to the development of some degree of tolerance.

Traumatic dental injuries in a sample of Dominican schoolchildren

The purpose of this retrospective study was to analyze 1) the prevalence of traumatic injuries to permanent incisors and canines, 2) their distribution according to type, 3) etiology, 4) place of occurrence, and 5) location of trauma, in a population sample of schoolchildren from the Dominican Republic, located in the Caribbean Archipelago. The sample consisted of 596 children aged 7-14 years enrolled in 21 public and private schools from the city of San Pedro de Macoris, in the southeastern part of the country. This sample represents 10.8% of the schoolchildren of the city. The prevalence of injuries was 18.1% (17.4% in boys and 18.8% in girls). The largest number of injuries was found in the 14-year-old children followed by the 12-year-olds. Significantly, girls had a larger number of actual teeth injured than boys (P less than 0.05). The most common type of injury in both sexes was the enamel fracture (51.1%) followed by concussions (25.6%). Significantly, more girls suffered concussions than boys (P less than 0.05). The most common cause of injury in both sexes was falling against an object (60.0% in boys and 42.6% in girls). The most frequent place of occurrence of trauma, in both sexes, was at home (34.1%), followed by outside of home (19.3%) and at school (12.5%). The teeth most commonly injured were the maxillary central incisors (63.9%). Girls presented significantly more mandibular lateral incisors injured than boys (P less than 0.02).

Low frequency hereditary deafness in man with childhood onset

A large kindred of hereditary deaf affected with a progressive sensorineural loss that begins during childhood with the low audiologic frequencies is described. Deafness progresses slowly through adolescence, when losses of up to 70 decibels are often detected. Affected adults present profound losses at all frequencies. Genetically, this deafness is transmitted as a simple, dominant, and autosomal mutation. No associated abnormalities have been detected in studies involving medical examinations, care histories, quantitation of several blood serum components, electrocardiograms, electrophoretograms, and karyotypes.