[Technics for artificial ventilation of a single lung during thoracotomy].
Different means of limiting the fall in arterial PO2 produced by single artificial ventilation were studied in 60 patients during thoracotomy. Changing from ventilating both lungs to the one healthy lung in the lateral recumbent position, without modifying tidal volume and frequency, brought about a fall in arterial PO2 from 180 +/- 56 to 67 +/- 40 mmHg. The alveolar to arterial oxygen gradient increased to 110 +/- 45 mmHg (the alveolar oxygen pressure being calculated). Reducing the tidal volume so as to keep the inflation pressure at its initial level did not improve the arterial PO2 but slightly increased the arterial PCO2 (2.3 mmHg). The use of 6 to 8 cm H2O positive end-expiratory pressure did not significantly modify the arterial PO2 or PCO2. Increasing the inspired oxygen fraction from 0.5 to 0.7 increased the arterial PO2 from 100 +/- 89 mmHg to 165 +/- 59 mmHg, whilst the alveolar to arterial oxygen gradient increased to 118 +/- 60 mmHg. Clamping the pulmonary artery increased the arterial PO2 and dual lung ventilation restored it to its initial value. Therefore, the only effective means of increasing oxygenation was to increase the inspired oxygen fraction. Unilateral continuous positive airway pressure was not used so as not to impair surgery. Dual lung ventilation may be necessary if the arterial PO2 remains low.
D001784:Blood Gas Analysis; D003250:Constriction; D006801:Humans; D008168:Lung / Q000502:physiology*; D008175:Lung Neoplasms / Q000601:surgery; D008482:Mediastinum / Q000601:surgery; D008875:Middle Aged; D011187:Posture; D011651:Pulmonary Artery; D011659:Pulmonary Gas Exchange; D012121:Respiration, Artificial / Q000379:methods*; D013903:Thoracic Surgery
Techniques de ventilation artificielle sur un seul poumon en cours de thoracotomie.