[Computerized multiple-choice questions: an efficacious method of evaluation in medical instruction?]. / Domande a scelta multipla computerizzate: un metodo di valutazione efficace nella didattica medica?

To evaluate the efficacy of Multiple Choice Questions (MCQ) as an evaluation tool in medical education, were analyzed the responses to 80 MCQ delivered by 300 physicians working in emergency departments and following a course on Basic and Advanced Life Support. Pre- and post-test were administered using a dedicated computer application running on PC. Students' scores were high and demonstrated both course and test validity. More than 95% of the students used the computer application without interface difficulties. However, some limits of MCQ were individuated: first, misinterpretation of some questions, especially when two or more similar answers were presented; from the other side, the student's personal experiences during the course practice could influence student's responses bringing him to different conclusions on respect to the instructor. These difficulties should be kept in mind in the development of a MCQ session, and students should have the possibility to give to the instructor a feedback of problems encountered during the course. This is especially important when MCQ are the sole evaluation technique.

Household bleaches based on sodium hypochlorite: review of acute toxicology and poison control center experience.

Bleaches based on solutions of sodium hypochlorite (NaOCl) are widely used in the household to disinfect and clean hard surfaces and to bleach the laundry. A review of both published and unpublished toxicological data is presented. In addition, the results of a survey of human accidents with hypochlorite bleaches by the Poison Control Centers of France, Italy, Belgium, Greece, Turkey, Spain and Portugal for the period 1989-1992 are presented. The data show that acute accidental exposure to household bleach in use or in foreseeable misuse situations results, in the great majority of the cases, in minor, transient adverse effects on health, with no permanent sequelae. Ingestion is the most frequent route of exposure, followed by inhalation of gases evolved by mixing sodium hypochlorite bleach with acid or alkaline products. All evidence presented confirms the normal safety profile of hypochlorite-based bleaches to be similar to that of other 'generally recognized as safe' household products.

Tympanometry for middle-ear effusion in unconscious ICU patients.

Eighty-six bilateral impedance audiometries were performed weekly in 35 unconscious ICU patients. Tympanometry showed the presence of middle-ear effusion in 43.3% of the examinations (80% of the patients). The incidence of effusion was significantly higher in patients older than 50 years, in intubated and mechanically ventilated patients and in the presence of microbial colonization of the upper airways. The acoustic reflex (AR) was characterized by increased threshold values in 23.8% of the examinations and was absent in 41.3%. Abnormal or absent ARs were usually associated with middle-ear effusion or tube malfunction.

Airway secretion electrolytes: reflection of water and salt states of the body.

Water and electrolyte content influences the rheology of respiratory mucus. Nasal secretions can be obtained from almost all patients and may be regarded as a possibly useful model of the electrolyte composition of lower airway secretions that are difficult to collect in most patients. Na, K, and Cl were determined from nasal secretions in 35 ICU patients. We studied the relationship of those values to the patients' water and salt states. Our study indicates that: a) lower K and Cl levels and higher Na levels than those found in plasma are common to both nasal and bronchial secretions; b) variations of electrolyte levels in nasal secretions are interrelated; c) patients with lower values of free-water clearance show lower Na and higher Cl levels in nasal secretions, possibly due to increased epithelial transport; d) the amount of K in nasal secretions appears correlated with its urinary fractional excretion (this could be explained by the variations in intracellular K levels); and e) in hyperchloremic patients, plasma/secretion differences of Na are decreased, possibly due to decreased epithelial transport.

pH and electrolytes in nasal secretum of intensive care unit patients.

Na, K and Cl levels and pH were determined in 26 samples of nasal secretum and plasma obtained from orally intubated intensive care unit patients. In nasal secretum K and Cl were higher and Na lower than in plasma: pH was higher in secretum than in plasma, probably because of the fall of CO2, which freely diffuses to the air. The epithelial activities of lowering pH, secreting K, and reabsorbing Na appeared closely linked together. The chloride difference (DCl) probably balanced the decrease of other anions, such as bicarbonate. Finally, some influences of plasmatic values on ion active transport rates may be hypothesized on the ground of the correlations of chloride and potassium values in nasal secretion and plasma.

Erythrocyte electrolyte abnormalities.

In contrast to lymphocytes and skeletal muscle cells, erythrocyte electrolytes may be easily determined. In this study Na, K, and Mg concentrations in plasma and erythrocytes of 100 consecutive ICU patients were compared to evaluate their potential clinical usefulness. The predictive indices of electrolyte changes in plasma vs. those in erythrocytes were low for all of the electrolytes studied. The erythrocyte Mg assessment was particularly useful for the high frequency of abnormalities observed, because it was less affected than plasma Mg by such transitory clinical states as hemodilution or lipolysis. The erythrocyte K was less frequently altered; no patient with a high K deficit was studied, excluding one patient with Crohn's disease. Finally, abnormally high erythrocyte Na levels correlated closely with some pathologic status, in particular respiratory failure.

Diagnostic, therapeutic, didactic, data bank utilization of computerized monitoring in a critical care center.

At the beginning of their discovery informatic technique procedures and methodologies generated a great wave of hopes for progress in theoretical and practical fields of human activity, but when passing to concrete application, an ebb phase followed. Recent theoretical and technical progress, however, has generated an enormous new up-surge of interest for applications of informatic processing in all fields of science. Medicine in the last three decades has gone through the same phases observed in other disciplines. In the ICU the potentiality of exploitation of the informatic techniques appeared enormous, however, initially from a practical point of view it found only limited, sectorial experimentation and implementation, but afterwards a limited and slow process of parcellar infiltration, the high tide of informatic, has broken the dam and deeply advanced in its territory, obliging the staff to a great effort of cultural and technical updating to cope with it. After recalling some of the history of Computer Science or Informatic, even if history was only yesterday, we will present some examples of the hand made experience of an ICU, (namely ours) with limited economical resources, and whose interest in this field arises from actual needs, personal interest and enthusiasm of a staff who works, on its free time, after fulfilling its stressing routine.

Effect of general anesthetics on human granulocyte chemiluminescence.

The effect of general anesthetics on human granulocyte 'phagocytic capacity' was tested, both in vivo and in vitro, by means of chemiluminescence. Halothane and ethrane produced a consistent degree of chemiluminescence inhibition, which, in vitro, was clearly dose-dependent.