[Plethysmographic and radiologic measurement of the total lung capacity during acute attack of bronchial asthma]. / Medición pletismográfica y radiológica de la capacidad pulmonar total durante un ataque agudo de asma bronquial.

There is controversy on the behavior of total lung capacity (TLC) during an acute asthma attack because the severe airflow obstruction causes an overestimation of the intrathoracic gas measured by plethysmography. We measured plethysmographic and radiologic TLC (TLCpl, TLCrx) in 17 patients with acute asthma, at admission and 3-5 days later when clinical and spirometric improvement was seen. TLCrx was measured planimetrically from routine chest X-rays in postero-anterior and lateral projection. Patients had a mean age of 32 +/- 15 years (ranging from 8-53) and six were males. FEV1 and FVC increased significantly in the second evaluation (1.36 +/- 0.7 vs 1.99 +/- 0.7 L, and 1.97 +/- 0.9 vs 2.6 +/- 1 L respectively, p less than 0.05), whereas airway resistance decreased (13.4 +/- 5.3 vs 9.8 +/- 3.4 cm H2O/L/s, p less than 0.05). On the other hand, we did not find a significant change in TLCpl (4.4 +/- 1.1 vs 4.6 +/- 1.2 L) nor in TLCrx (4.2 +/- 0.9 vs 4.1 +/- 0.8 L). We found no significant difference between TLCpl and TLCrx.

[Radiographic measurement of the total pulmonary capacity: comparison of 2 planimetric methods]. / Medición radiográfica de la capacidad pulmonar total: comparación de dos métodos planimétricos.

We analyzed accuracy and reproducibility of a radiographic method for calculation of total lung capacity (TLC) from the sum of pulmonary area. Pulmonary area from a routine postero-anterior and lateral chest radiography was measured by two methods: using a planimeter (standard) and with a virgin radiographic plaque with lines separating squares of 1cm per side. Plethismographic TLC was obtained adding the functional residual capacity to inspiratory capacity. We studied 13 healthy subjects (mean age of 30 years, eight males), 13 with interstitial lung disease (mean age of 45 years, two males) and 12 with chronic bronchitis or emphysema (mean age of 63 years, three males). Measured TLC varied from 1.9 to 7.2 liters. The linear regression equation found was: TLC = 0.007 total lung area (cm2) 0.572, R = 0.906, P less than 0.001 which is very similar to that reported by Harris et al.8 Interobserver variability in the measurement was very small taking into account that no efforts were made to uniformize the observers. Main interobserver differences were in the tracing of the lung limits, and not in the actual measurement of the lung area. We found no differences between the two methods for measuring lung area except that the planimeter is faster and more reproducible. Radiographic method for measuring TLC is accurate and available in most places.

[Iatrogenic trends as indicator of clinical competence in courses of specialization in medicine]. / Tendencias iatrogénicas como indicador de competencia clínica en los cursos de especialización en medicina.

Iatrogenesis, understood here as an unfavourable effect to the health of patients provoked by the medical institution, has risen little interest in the researchers of the health area in spite of its growing presence. The present study had the aim of exploring the iatrogenic behavior of 659 recently graduated physicians by a questionnaire composed by clinical cases which described diagnostic and/or therapeutic situations that required the making of decisions. The questionnaire consisted of 600 general medical knowledge questions of which 112 explored commission of iatrogenic behavior. The group showed a iatrogenicity index of 39.5% ranging between 15.2% and 74.1%. When this iatrogenicity index was compared to that of global medical knowledge (600 questions) no correlation was found. It is concluded that the "iatrogenicity" index of this group is high and lacks correlation with the global medical knowledge. This suggests that the individualized and careful use of the diagnostic and therapeutic resources suitable for specific situations in patients does not receive sufficient emphasis during the teaching-learning process nor does it play a prominent role within the priorities of knowledge that are learned in the school of medicine. The need to deepen our understanding of the iatrogenic behavior of the physicians at different levels of their professional training is emphasized.