[Distribution of pulmonologists and chest surgeons in Spain]. / Distribución de neumólogos y cirujanos torácicos en España.

OBJECTIVE: To study the real situation of respiratory medicine specialists and chest surgeons in the Spanish health service. SUBJECTS AND METHOD: Using the database of the secretary of the Spanish Society of Respiratory Medicine and Chest Surgery (SEPAR) for 1999, we gathered data on 326 Spanish hospitals. We were thus able to ascertain the level of staffing of respiratory medicine and chest surgery departments. The results were expressed as simple percentages showing distribution by age, duties and geographic area. The number of specialists per 100,000 inhabitants in each community was also calculated based on population data provided by the National Statistics Institute for 1997. RESULTS: We studied 1,786 physicians or surgeons (1,245 pneumologists, 185 surgeons and 356 from other specialties). The mean age was 41 9 years for pneumologists, 44 10 years for surgeons and 51 8 years for the others. We observed unequal distribution by geographic area, with a high of 6.66 pneumologists and 0.9 surgeons per 100,000 inhabitants in Asturias and Madrid, respectively and a low of 1.4 pneumologists per 100,000 inhabitants in Murcia and 0 surgeons in Extremadura. CONCLUSIONS: Specialist coverage by pneumologists and chest surgeons is inadequate in many provinces and communities in Spain. The professional market is not saturated, indicating that future specialists can look forward to market demand.

[Evolution of Spanish scientific production in international respiratory system journals from 1987 to 1998]. / Evolución de la producción científica española en revistas internacionales de sistema respiratorio de 1987 a 1998.

BACKGROUND: A relevant increase in the clinical relevance of respiratory system area has occurred in the last few years. The aims of this study were: to analyze the evolution of production and impact of Spanish scientific activity in the respiratory system area between 1987 to 1998; and to assess the participation of the different Spanish autonomic communities in this activity. METHODS: Papers published in 38 international journals of respiratory system during this period of time were selected by the MedLine system, delimiting Spanish production. Geographical and institutional distribution of the production, specialist of authors, main publication journals and type of publication were recorded. Production and impact bibliometric indicators were estimated. RESULTS: The number of Spanish documents from 1987 to 1998 multiplied by eight, reaching the 1.49% of the total published documents in 1998. However, the growth model of scientific production during this period was lineal. The increase in the scientific production was associated with a increase over time in the expected impact factor. In 1998, expected impact factor was 2. 206. Forty-two percent of the papers were signed by pneumologists. The highest contributor were hospitals. The most productive autonomous communities were Catalonia, Cantabria and Madrid. The communities with the highest expected impact factor were Balears and Catalonia. CONCLUSIONS: A relevant increase has occurred in the scientific production and impact of Spanish biomedical activity in respiratory system area.

[Respiratory function in pediatric survivors of malignant neoplasms]. / Función respiratoria en niños supervivientes de neoplasia maligna.

AIM: To evaluate post-treatment pulmonary function in patients with malignant extrapulmonary neoplasia and its relationship with age, type of neoplasty and treatment received. METHODS: Cohort study of 95 pediatric patients after chemotherapy with or without surgery or extrapulmonary thoracic radiotherapy. The patients were in remission without treatment and able to undergo pulmonary function testing. Personal history and exposure to risk factors or toxic habits were evaluated. Clinical examination, chest radiographs, pulmonary gammography, basal and stress pulmometry, forced spirometry, whole body phletismography and carbonmonoxide transfer test were performed. RESULTS: Mean age at diagnosis was 5 +/- 3.3 years. Treatment duration was 2.4 +/- 1.3 years and time without treatment 4.3 +/- 3. 3 years. Thirty-six patients were reviewed two and a half years after the first control. Thirty-nine patients had acute lymphoblastic leukemia and 57 had solid tumors. Sixty percent showed functional restriction due to chest deformity after undergoing chest surgery. The association between functional restriction and radiotherapy (6 patients) did not produce poorer functional results. Forty-three percent showed initial change in TLCO. Nineteen percent showed basal hemoglobin saturation under 93% which in 16% fell after physical exercise. These alterations improved with time. However, restrictive change initially present in 11.5% persisted at the second evaluation. Thoracic surgery was the main cause of thoracic deformity and therefore of restrictive change. The children under 8 years old and those who received longer treatments tended to show the worst TLCO values. The patients with neuroblastoma showed greater restrictive change while the change in TLCO was more frequent in patients with Burkitt s lymphoma and in those treated with cyclophosphamide. CONCLUSIONS: Neither personal or family history of respiratory disease nor the presence of symptoms such as cough served to identify risk of functional change. Restrictive change in pulmonary function was greater in patients who had undergone thoracic surgery. Functional values were worse in patients with neuroblastoma. Pulmonary function should be followed up in pediatric survivors of malignant neoplasia in order to prevent restrictive alterations.

[The sleep apnea syndrome as a health problem. An estimation of its prevalence and morbimortality]. / El síndrome de apneas durante el sueño como problema sanitario. Valoración de su prevalencia y morbimortalidad.

The sleep apnea syndrome (SAS) is a frequent health problem and has severe consequences. In some reports, their main symptoms like habitual snoring, excessive daytime sleepiness and nocturnal respiratory pauses can affect up to 65, 22.2 and 27.9% of men, respectively, being less frequent in women. The incidence of SAS ranges between 4 and 7% of adult general population. Patients without treatment have an increased mortality (37% to 8 years). Between the complications that made this adverse outcome are cardiovascular problems (arterial hypertension, coronary artery disease, sudden death), cerebral infarctions and other derived from sleepiness like traffic crashes.

Long-term within-subject variability of inspiratory neural drive response to hypoxia.

STUDY OBJECTIVE: We analyze the within-subject variation of mouth occlusion pressure (P0.1) response to progressive isocapnic hypoxic stimulation over long time periods in normal subjects. PATIENTS AND INTERVENTIONS: We studied 21 healthy subjects (14 male and 7 female; aged 40+/-12 yrs) (mean+/-SD). Lung volumes, basal P0.1, and P0.1 response to hypoxia were measured on two separate occasions 2 months apart, under similar ambient and clinical conditions. RESULTS: There was no significant change in clinical condition, FVC, FEV1, arterial oxygenation saturation, end-tidal and mixed venous PCO2 levels, or P0.1 between the two visits. The mean P0.1 responses to hypoxia in the two explorations were 0.032+/-0.022 and 0.034+/-0.022 kPa/%, respectively. There was a moderate intrasubject variability of P0.1 response to hypoxia, with a coefficient of reproducibility of 0.01 kPa/%. Power calculations to establish the optimal sample size required for hypoxic stimulation are presented. CONCLUSION: Long term within-subject variability of P0.1 response to hypoxia is moderate. This intrinsic variability needs to be emphasized when interpreting the effects of experimental interventions on hypoxic sensitivity.

Regulation of breathing in hyperthyroidism: relationship to hormonal and metabolic changes.

We sought to examine the breathing pattern, inspiratory drive and chemosensitivity of hyperthyroid patients and to explore the interactions between their thyroid hormones, basal metabolism and chemosensitivity. We studied 15 hyperthyroid patients and 15 sex- and age-matched controls. Thyroid hormone levels, arterial blood gas tensions, lung volumes, diffusing capacity for CO, maximal respiratory pressures and oxygen uptake measurements were performed. Breathing pattern and mouth occlusion pressure (P0.1), as well as ventilatory and P0.1 responses to hyperoxic progressive hypercapnia and isocapnic progressive hypoxia, were also evaluated. Compared with the control subjects, the hyperthyroid patients showed significantly lower resting arterial CO2 tension, tidal volume and significantly higher mean inspiratory flow and P0.1. Ventilatory and P0.1 responses to CO2 and hypoxia were also greater in the hyperthyroid patients than in the control group. All these changes returned to normal after treatment. In the patients, significant relationships between tri-iodothyronine and P0.1, P0.1 response to hypoxia, and P0.1 response to hypercapnia were found. In contrast, in hyperthyroidism there was no relationship between oxygen uptake and P0.1 response to hypoxia. We conclude that hyperthyroid patients exhibit a significant relationship between their thyroid hormone levels and their increased inspiratory drive and chemosensitivity.

Comparison of helium dilution and plethysmographic lung volumes in pregnant women.

The multibreath helium equilibration method is the technique recommended for routine measurement of static lung volumes in normal subjects. However, pregnancy could be an exception to this general rule, due to airway closure during the second half of gestation. The aim of this study was to compare the measurements of lung volumes by plethysmography and helium dilution during pregnancy. Twenty three healthy women were studied at 12, 24 and 36 weeks of pregnancy, and 4 months postpartum. Total lung capacity (TLC), functional residual capacity (FRC) and residual volume (RV) were measured by multibreath helium equilibration (TLCHe, FRCHe and RVHe) and by plethysmography (TLCbox, FRCbox and RVbox). Only at 36 weeks were there differences between the two methods. RVbox was significantly larger than RVHe (1.01+/-0.18 vs 0.77+/-0.21 L; p<0.001). FRCbox was larger than FRCHe (1.95+/-0.32 vs 1.60+/-0.32 L; p<0.001) and TLCbox was larger than TLCHe (4.83+/-0.52 vs 4.45+/-0.51 L; p<0.05). The 95% limits of agreement for differences between lung volumes measured by the two techniques (helium dilution - plethysmography) at 36 weeks were: -0.42 to -0.06 L for RV; -0.54 to -0.17 L for FRC; and -0.66 to -0.11 L for TLC. We conclude that using the multibreath helium equilibration method to measure lung volumes in at-term pregnant women results in underestimation of functional residual capacity and total lung capacity.

[Estimation of initial interobserver variability of forced spirometry in the multicenter epidemiological study IBERPOC. Scientific Committee of the IBERPOC study]. / Estimación de la variabilidad inicial interobservador de la espirometría forzada en el estudio epidemiológico multicéntrico IBERPOC. Comité Científico del Estudio IBERPOC.

To estimate the interobserver variability and degree of agreement for basic spirometric parameters before beginning field work for the IBERPOC Project. Study of agreement between 7 observers (pneumologists) and a gold standard, using a scheme of incomplete balanced and randomized blocks with an equal number of spirometric measurements (n = 3) per patient and an equal number of measurements (n = 9) per observer performed at the same session. The study population consisted of 14 patients with different degrees of air flow obstruction and 7 normal volunteers. Statistically significant differences attributable to subjects (inter-patient variability) were found for the three variables analyzed. Variability attributable to the observer was found for FVC and FEV1 but not for FEV1/FVC. The greatest interobserver differences were found for FEV1, such that 4 of the 7 observers recorded values that were significantly different from the mean (p < 0.05). The differences were less marked for FVC and for the FEV1/FVC ratio, with only 2 observers recording significantly different values for each variable. The high degree of reproducibility as well as the excellent interobserver agreement found in this standardization session provide an a priori guarantee of validity for spirometric measurements and rule out the existence of differential bias in data recorded at the various geographic areas involved in the study.

Short-term effects of inhaled beta-adrenergic agonist on breathlessness and central inspiratory drive in patients with nonreversible COPD.

In patients with COPD, a relationship between breathlessness and respiratory effort, assessed in terms of mouth occlusion pressure (P0.1), has been described. To evaluate the short-term effects of inhaled terbutaline on breathlessness, breathing pattern, and P0.1 in patients with nonreversible COPD, we designed a randomized, double-blind, parallel, placebo-controlled study. Twenty-five patients with stable nonreversible COPD, mean age 64 +/- 11 years, were enrolled in the study. Patients received 500 micrograms inhaled terbutaline or placebo. Breathlessness, using the Borg scale, breathing pattern, and P0.1 were measured at baseline and 30 min after inhalation. Terbutaline resulted in a significant decrease in Borg scale, while no differences were observed after placebo. No significant changes in breathing pattern were found. Nevertheless, a decrease in P0.1 (0.31 +/- 0.07 vs 0.21 +/- 0.05 kPa; p < 0.001) after terbutaline inhalation was observed. Borg score was correlated with P0.1 in all patients. Moreover, changes in Borg score after medication were directly proportional to P0.1 changes (r = 0.85; p < 0.01). We conclude that terbutaline decreases central inspiratory drive and improves breathlessness in patients with nonreversible COPD.

[Preliminary results of a program of home oxygen therapy using transtracheal catheter]. / Resultados preliminares de un programa de oxigenoterapia domiciliaria por catéter transtraqueal.

We present our experience with oxygen-therapy with transtracheal catheter in the period between January 1990 and December 1991. This procedure was offered to 130 patients who met criteria of home oxygen-therapy being accepted only by twelve. Ten patients maintained oxygen-therapy with transtracheal catheter with excellent results and a notable improve in their quality of life. One patient died twenty-three days after beginning the procedure, due to evolution of main disease finding no role of the catheter in the disease. Another patient showed a vagal reaction after placement of the catheter, which forced to perform resuscitation with connection to mechanical ventilation taking the catheter off because familiar request. Patients who benefit this type of oxygen-therapy the trans-tracheal catheter has showed its usefulness. With few complications and showing no problems in its home handling. Oxygen savings with this technique have been of 55%. Trans-tracheal catheter was much more effective than face mask to correct desaturation after exercise (p less than 0.001).

[Primary pulmonary actinomycosis: the experience in a general hospital]. / Actinomicosis pulmonar primaria: experiencia en un hospital general.

Although all Actinomyces species are capable of producing primary pulmonary pathology, actinomycosis is a rare entity which is infrequently diagnosed. The clinician's lack of knowledge of the disease is frequently blamed for this, and it is estimated that its incidence in our environment is greater than suspected. We present our experience consisting of four cases of primary pulmonary actinomycosis (PPA) diagnosed at La Paz Hospital from 1974 to 1988. Its particular characteristics are emphasized as well as the need to include it in the differential diagnosis of chronic pulmonary infiltrations, cavitated lesions or pulmonary masses.