Saltos del Moconá Río Uruguay - Misiones Argentina Evaluación de la broncodilatación Dr. Hernando Sala Hospital Nacional A Posadas El Palomar - Argentina

Evaluación de la Broncodilatación Curvas flujo-volumen máximos en un paciente asmático antes (línea llena) y después (línea discontinua) de la administración de un broncodilatador

Diagrama esquemático del efecto agudo causado por la inhalación de un broncodilatador, en un paciente con asma de gravedad variable. La mejoría de FEV1 (línea discontinua) suele ser mayor cuando su valorar pre-broncodilatador está moderadamente reducido.

Relación entre FEV1 y la respuesta bronquial a la metacolina (PC20 mg ml –1) en pacientes con EPOC

CHANGES IN RESIDUAL AIR VOLUME AFTER THE USE OF BRONCHODILATOR AGENTS KANAZIRSKI P, TSANEV B, BACHVAROV L. Probl Tuberk. 1963;41:77-81.

Olive and Hyatt 1978

Broncodilatación y DLCO Effect of bronchodilatation on single breath pulmonary uptake of carbon monoxide in chronic obstructive pulmonary disease. Baldi S, Fracchia C, Bruschi C, Dore R, Maestri R, Brusasco V, Pellegrino R. Int J Chron Obstruct Pulmon Dis. 2006;1(4):477-83.

Bronchoconstrictor effects of a deep inspiration in patients with asthma. Gayrard P, Orehek J, Grimaud C, CHarpin J. Am Rev Respir Dis. 1975 Apr;111(4):433-9. A deep inspiration from functional residual capacity to total lung capacity, performed at a low flow rate by a group of 40 unselected adult patients with asthma, yielded an immediate and transient increase (71 per cent, P smaller than 0.001) in specific airway resistance. In 2 of the 40, deep inspiration provoked an attack of asthma. The effect of deep inspiration can be attributed to a vagal bronchoconstrictor reflex, because it was prevented or decreased in most of the cases by inhalation of an anticholinergic drug. Beta-adrenergic blockade by propranolol potentiated in a minority of subjects the bronchoconstrictor response to deep inspiration. Deep expiration also induced a bronchoconstrictor effect, which was weaker than that of deep inspiration. It follows that functional studies of asthmatics may be biased if the technique requires maximal respiratory maneuvers.

Curvas V/V Parciales Reversibility of the pulmonary function based on the partial flow-volume curve predicts the efficacy of bronchodilator therapy for treating chronic cough. Nakade Y1, Fujimura M, Ohkura N, Nakata M, Nanbu Y, Oe H, Horita H, Sakai Y, Wada T. Intern Med. 2013;52(18):2017-23. OBJECTIVE: Partial expiratory flow-volume curves have the potential to detect mild bronchoconstriction because they are not affected by the modulatory effects of deep inspiration. The aim of this study was to investigate the relationship between the efficacy of bronchodilator therapy (BDT) in treating the cough and to assess the increase in the expiratory flow of the partial flow-volume curve at 40% above the residual volume level (PEF40) caused by treatment with a short-acting beta-2 agonist (SABA) in patients with chronic nonproductive cough. METHODS: We measured the reversibility of PEF40 caused by a SABA in 42 patients with chronic nonproductive cough at visit 1 (day 0). The patients received BDT for six days. The visual analogue scale (VAS) was used to assess the efficacy of BDT in treating coughing at visit 2 (day 7) (0 mm, 'no cough;' 100 mm, 'no change in coughing'). RESULTS: Reversibility of the PEF40 was correlated (r=0.690, p<0.001) with the VAS score determined at visit 2 and was higher in the patients with cough variant asthma (CVA) (44.9 ± 18.3%) than in those with atopic cough (13.4 ± 10.4%) (p<0.01). CONCLUSION: Reversibility of the PEF40 predicted the efficacy of BDT in patients with chronic nonproductive cough and helped to identify patients with CVA.

Airways flow resistance as a measure of the efficacy of inhalants in clinical drug trials. Cohen BM. Helv Med Acta. 1969 Mar;34(6):455-67.

. Forced oscillation technique vs spirometry to assess bronchodilatation in patients with asthma and COPD. Zerah F, et al Chest. 1995 Jul;108(1):41-7 We conclude that the use of FOT can be considered as an alternative to forced expiration for detecting bronchodilatation in asthmatics and patients with COPD.

Sensitivity of impulse oscillometry and spirometry in beta-blocker induced bronchoconstriction and beta-agonist bronchodilatation in asthma. Short PM, Williamson PA, Lipworth BJ. Ann Allergy Asthma Immunol. 2012 Dec;109(6):412-5.

Impulse oscillometry: interpretation and practical applications. Bickel S, Popler J, Lesnick B, Eid N. Chest. 2014 Sep 1;146(3):841-7.  FOT La mejor manera de medir la broncodilatación en población pediátrica

Diagrama del diseño de un equipo para medir resistencia Neumotacógrafo Pieza bucal Caja de madera Malla Transductores de presión Circuito Tubo flexible Parlante Diagrama del diseño de un equipo para medir resistencia Monaldi Arch Chest Dis, 2001; 56:6, 555-582

Amplificadores Convertidor A/D Polígrafo PC Transductor de presión Generador de señal Neumotac Parlante Tubo flexible Caja

Señal de presión registrada en la boca Señal de flujo Presión Flujo R =Delta P/V Impedancia calculada Monaldi Arch Chest Dis, 2001; 56:6, 555-582

A partir del estudio de las presiones resultantes que se encuentran en fase y fuera de fase en relación con la señal se pueden calcular tanto la resistencia como la reactancia.

Impedancia del sistema respiratorio: es la suma de la resistencia y la reactancia Zx = Rrs + Xrs La reactancia es la suma de la elastancia y la inertancia, en electricidad capacitancia e inductancia respectivamente. Xrs = XC + XL Inertancia Resistencia Reactancia Elastancia Impedancia

Forced Oscillation Technique (FOT) Aplicaciones Clínicas Pruebas de broncodilatación y broncoconstricción No necesita inspiración profunda ni espiración forzada

Meseta de Somuncurá Patagonia Muchas Gracias

Frecuencia de resonancia Los cambios de presión dependen solo de la resistencia Inertancia Resistencia (Reactancia) Impedancia Elastancia