Single lung transplantation was performed in several steps: laparotomy to prepare an omentopexy, followed by pneumonectomy and implantation of a pulmonary graft, both by postero-lateral thoracotomy. The patients suffered from lymphangiomyomatosis (1), panacinar emphysema (2) and idiopathic pulmonary fibrosis (1). Immunosuppressive treatment was started before surgery. Anaesthesia was induced and maintained with alfentanil, midazolam and vecuronium. The patients were intubated with a Carlens endotracheal tube. Ventilation was carried out using an oxygen-air mixture, without any nitrous oxide or halogenated anaesthetic agent. Besides the usual parameters, expired CO2 concentrations, and oxygen saturation in the pulmonary artery were monitored. Partial femoro-femoral cardiopulmonary bypass was not required. Three major problems were encountered: hypoxia, hypercapnia, and pulmonary arterial hypertension. Hypoxia first occurred during the period of one-lung ventilation, during pneumonectomy, and again after unclamping of the graft vessels before the bronchus had been anastomosed. It was treated either by increasing the FiO2, inflating the lungs with pure oxygen, or partial clamping of the homolateral pulmonary artery. Hypercapnia occurred in three of the four patients until the graft was ventilated again. Except in one patient with preoperative pulmonary hypertension, the increase in pulmonary vascular resistances remained moderate after clamping of the pulmonary artery. Sufficient oxygen delivery, with more than 50% venous oxygen saturation, was maintained at this time by the infusion of dopamine and dobutamine. Two other specific problems were encountered in the emphysematous patients: severe hypotension following the start of artificial ventilation and after placing the patient in lateral position; thoracic asymetry with overdistension of the emphysematous lung, and mediastinal shift.(ABSTRACT TRUNCATED AT 250 WORDS)