Single lung transplantation for chronic obstructive pulmonary disease: pulmonary function and impact of bronchiolitis obliterans syndrome

AbstractChronic obstructive pulmonary disease (COPD) is now the most common indication for single lung transplantation. In long-term follow-up, obliterative bronchiolitis is a major problem. The aim of the present study was to perform a long-term follow-up of the pulmonary function and to examine the effect of development of bronchiolitis obliterans syndrome (BOS).Nineteen patients with end-stage COPD underwent single lung transplantation and were followed regularly with pulmonary function tests, and ventilation and perfusion scintigraphy (mean observation time 29 months). They were divided into two categories, with and without BOS, using the definition recommended by the International Society for Heart and Lung Transplantation working group. A mixed model analysis of variance with BOS as co-variate was used to evaluate its effect on pulmonary function.Spirometry, lung transfer factor for carbon monoxide (TlCO), arterial blood gases and 6-min walk test improved significantly (P<0·001) from before transplantation to 3 months after transplantation. Nine patients developed BOS. Implied by the definition of the syndrome, forced expiratory volume in 1 s (FEV1) was significantly (P<0·001) lower for patients with BOS while there was no significant effect of BOS category on TlCO corrected for alveolar volume (Va) or perfusion to transplant. Patients without BOS maintained their pulmonary function, and ventilation and perfusion to transplant for more than 3 yr after transplantation.The present results suggest that decreasing FEV1 accompanied by an unchanged TlCO/Va and pulmonary perfusion support the diagnosis of BOS after single lung transplantation for COPD

Central venous catheters may be a potential source of massive air emboli during vascular procedures involving extracorporeal circulation: an experimental study

Central venous catheters are mandatory during every major procedure involving extracorporeal circulation. Air emboli potentially could enter the circulation through this device when negative pressure is applied in the venous cannula. The following experimental study was initiated by a fatal massive air embolus during a vascular procedure involving cardiopulmonary bypass. An experimental setup was established, simulating a real scenario. The experiment was performed with a 40% glycerol/water mixture which exhibits properties and fluid dynamics close to blood. A heart-lung machine provided circulation of the fluid. The flow was adjusted according to the gravitational status. A triple-lumen central venous catheter with one line open to air was lowered into the liquid. The disconnected lumen of the central venous catheter was manipulated so it approached and was located in close proximity to the venous cannula. An air flow of up to 300 ml/min could be obtained from the central venous catheter with a flow in the cardiopulmonary bypass circuit of 2.3 L/min. A linear relationship was observed between flow in the circuit and air flow. Consecutive measurements proved consistent with acceptable results, proving that a disconnected central venous catheter might, under certain circumstances, be a source of massive air emboli during cardiopulmonary bypass. </jats:p