Lung transplantation is the treatment of choice for patients with end-stage lung failure. Limitations are presented by the shortage of donors and the long waiting list periods. New techniques, such as extracorporeal membrane ventilator devices with or without pump support, have been developed as bridges to transplantation for patients with severe, unresponsive respiratory insufficiency. Between November 2005 and September 2009, 12 patients (7 males and 5 females), of overall mean age of 43.3 +/- 15.5 years underwent decapneization with extracorporeal devices. In 6 cases, a NovaLung system was used; in the remaining 6 patients, it was a Decap device. Causes of respiratory failure that led to implantation of such devices were cystic fibrosis (n = 6), pulmonary emphysema (n = 5), and chronic rejection of a previous double lung transplant (n = 1). Mean time on extracorporeal decapneization was 13.5 +/- 14.2 days. Eight patients died on the device. Three patients were bridged to lung transplantation; 1 recovered and was weaned from the device after 11 days. Mean PaCO(2) on the extracorporeal gas exchanger was significantly lower for both the devices at 24, 48, and 72 hours after implantation (P < .05). No significant difference was observed for the 2 systems. In our initial experience, decapneization devices have been simple, efficient methods to support patients with mild hypoxia and severe hypercapnia that is refractory to mechanical ventilation. This could represent a valid bridge to lung transplantation in these patients.
24 July 2014 in European Journal of Cardio-Thoracic Surgery
Ex vivo lung perfusion (EVLP) is a novel technique used to evaluate and recondition marginal or rejected grafts. Primary graft dysfunction (PGD) is a major early complication after lung transplantation (LTx). The use of marginal or initially rejected grafts may increase its incidence and severity. The aim of this study is to evaluate the incidence of PGD after LTx using rejected grafts reconditioned with EVLP. PGD has been evaluated immediately after LTx (t0) and after 72 h (t72) in patients receiving standard (Group A) or reconditioned (Group B) grafts. EVLP was performed using a controlled acellular perfusion according to the Toronto technique. From July 2011 to February 2013, 36 LTxs have been performed: 28 patients (21 M/7 F, mean age 51.7 ± 14.7 years) in Group A and 8 (6 M/2 F, mean age 46.6 ± 9.8 years) in Group B (successful recondition rate of 73%, 8 of 11 cases). Incidence rate of PGD 3 at t0 and at t72 (Group A versus Group B) was 50 vs 37% (P = NS) and 25 vs 0% (P = NS), respectively. Post-transplant extracorporeal membrane oxygenation was required in 5 and 2 patients in Groups A and B, respectively (P = NS). The use of initially rejected grafts treated with EVLP does not increase the incidence and severity of PGD after LTx. Although comparison of PGD 3 incidence in the two groups did not reach a statistical difference, all EVLP patients suffering from severe PGD early after transplant recovered normal lung function at 72 h, suggesting a protective role of EVLP against PGD occurrence and severity.
Background During ex vivo lung perfusion (EVLP), fixed ventilator settings and monitoring of compliance are used to prevent ventilator-induced lung injury (VILI). Analysis of the airway pressure-time curve (stress index) has been proposed to assess the presence of VILI. We tested whether currently proposed ventilator settings expose lungs to VILI during EVLP and whether the stress index could identify VILI better than compliance. Methods Flow, volume, and airway opening pressure were collected continuously during EVLP. Durations of mechanical ventilation, intensive care unit (ICU) and hospital lengths of stay were recorded in lung recipients. Results Fourteen lungs underwent EVLP and were transplanted. In 5 lungs, 95 ± 2% of the stress index values were within the 0.95 to 1.05 range (protected); in the remaining nine lungs, 69 ± 1% of the values were greater than 1.05 and 15 ± 3% were less than 0.95 (nonprotected). There was a significant (P < 0.05) increase in cytokine concentrations after 4 hours of EVLP in the nonprotected lungs. Durations of mechanical ventilation, ICU, and hospital lengths of stay were shorter in recipients of protected than that of nonprotected lungs (P < 0.05). There was no correlation between compliance during EVLP and duration of mechanical ventilation or ICU and hospital lengths of stay in recipients, but the stress index during EVLP was significantly correlated with the duration of mechanical ventilation and with ICU and hospital lengths of stay (P < 0.05). Conclusions This small, preliminary study shows that ventilator settings currently proposed for EVLP may expose lungs to VILI. Use of the stress index to personalize ventilator settings needs to be tested in further clinical studies.