s and Programme: EUROANAESTHESIA 2011: The European Anaesthesiology Congress: Paediatric Anaesthesia and Intensive Care

Background: Measurement of intrapleural pressure is useful during various pleural procedures. However, the availability of electronic pleural manometers is limited. Objectives: We aimed to 1) construct an electronic pleural manometer, 2) assess the accuracy of the measurements done with a new device, 3) perform an initial evaluation of the device during thoracenthesis. Methods: A vascular pressure transducer was used to transform hydrostatic pressure into an electronic signal. Reliability of the measurements was evaluated in a laboratory setting by comparing the results with those measured by a water manometer. Functionality of the device was assessed during thoracentesis and artificial pneumothorax creation before medical thoracoscopy. Results: We built a small device, which can precisely measure intrapleural pressure. The measurement results showed a very high agreement with those registered with a water manometer (r=0.999; p<0.001). The initial evaluation of the electronic manometer during pleural fluid removal and pneumothorax creation showed the mean initial intrapleural pressure 3.85 cmH 2 O which decreased steadily to -8.98 cmH 2 O after the removal of 1600 ml of pleural fluid and increased up to -1.29 cmH 2 O after insertion of 1000 ml of air. The procedure was safe, the only symptom recorded was cough which appeared after the withdrawal of 900 ml of pleural fluid (intrapleural pressure -1.96 cmH 2 O). Conclusion: Our electronic pleural manometer can precisely measure intrapleural pressure during pleural fluid removal and pneumothorax creation. The procedure of pleural pressure monitoring during thorcentesis is easy to perform and safe.

A new control solution for independent, synchronous ventilation of lungs has been developed and a controller to perform it with use of only one respirator and a bilumen intubation tube has been built. The controller enables division of the inspiratory tidal volume between the lungs in desired ratio, and setting of the positive end-expiratory pressure (PEEP) separately for each lung. The model tests have shown that the characteristics of the flow meters used, however not linear, is good enough to achieve clinically accepted accuracy of volume division. The tests have shown that the volume division is independent from the total tidal volume and PEEP. Maximal errors of the tidal volume division was less than 10%. The case study of patient after lung injury has shown significant improvement of the X-ray image and respiratory parameters (blood oxygenation, ventilatory pressures) during the independent ventilation of lungs with the use of the new device. The clinical study of 60 patients has shown that differences between actually realized volume division and the adjusted values are practically negligible.

The aim of this work is building a hybrid model of the human respiratory system which enables connecting the real clinical devices (respirators) with the. computerized virtual lungs. A simulation of the artificial ventilation of lungs, with the use of the hybrid model and the Siemens Servo 900 respirator, was made. Waveforms of pressure inside the lungs, flow in the respiratory tract, and the lung volume during the simulated artificial ventilation were recorded. The compliance and resistance of the hybrid model of the respiratory system were calculated on the basis of the inspiratory pause algorithms and compared to the values set in the model. The initial tests have shown that the calculated values of the parameters differ by 20% (worst result) from the values set in the model. The model will enable the investigation of the different modes of lung ventilation, as well as educational presentation of the respirator-patient interaction.

Aim: The objective of this study was to access the ability to control and stabilize ventilation of each lung by a newly developed flow/ventilator divider.