Adobe Systems Physiology department 1 Spirometry Adobe Systems Physiology department 2 Types of spirometers ̶pressure differences between the inner and outer spirometer membranes ̶air flow velocity according to the speed of the turbine rotation Adobe Systems Physiology department 3 Static parameters ̶Tidal volume (TV) – the volume of air that enters the lungs during each inspiration (or the volume that is exhaled during every expiration). ̶Inspiratory reserve volume (IRV) – the maximal amount of additional air that can be drawn into the lungs by determined effort after a normal inspiration at rest. ̶Expiratory reserve volume (ERV) – the additional amount of air that can be exhaled from the lungs by determined effort after a normal expiration. ̶Residual volume (RV) – the volume of air still remaining in the lungs after the most forcible expiration possible. ̶ V [l] Vt (0,5 l) IRV (2,5 l) ERV (1,5 l) RV (1,5 l) Adobe Systems Physiology department 4 Static parameters Lung capacity: ̶VC = VT + IRV + ERV ̶TLC = VC + RV ̶FRC = ERV + RV ̶IC = IRV + VT ̶EC = ERV + VT ̶ Vt (0,5 l) IRV (2,5 l) ERV (1,5 l) RV (1,5 l) V [l] Dynamic lung volumes: ̶VE ̶MMV ̶ Adobe Systems Physiology department 5 Dynamic parameters V [l] Dynamic lung volumes: ̶Minute ventilation ̶Apneic pauses (inspirium/expirium) ̶Frequency of breathing Apneic pause Frequency time Adobe Systems Physiology department 6 Dynamic parameters Dynamic lung volumes ̶ V [l] Time [s] 1 s FEV1 ―FVC – the maximum volume of air that can be exhaled after maximum inhale ―FEV1 – the volume of air exhaled with the greatest effort in 1 second after maximum inhale ―FEV1/FVC (%) – Tiffeneau index – around 0,8 (80 %) Adobe Systems Physiology department 7 Obstructive/restrictive lung disease 1 s V [l] Time [s] 1 s V [l] Time [s] FEV1 FEV1 FVC > FVC Obstructive lung disease (FVC=N; FEV1=↓) ―tracheal stenosis ―astma bronchiale ―CHOPN ―tumor Restrictive lung disease (FVC=↓; FEV1=N) Pulmonary etiology ―pulmonary fibrosis ―lung resection ―pulmonary edema ―pneumonia Extrapulmonary etiology ―ascites ―kyphoscoliosis ―burns ―high diaphragm condition Adobe Systems Physiology department 8 Flow - volume curve •PIF – peek inspirátory flow; the highest speed of air flow at peak of inhale •PEF – peek expiratory flow; the highest speed of air flow at peak of exhale •FEF – maximum expiratory flow rates at different FVC levels (75 %, 50 % and 25 % of FVC) Adobe Systems Define footer – presentation title / department 9 Adobe Systems Define footer – presentation title / department 10