LUNG-MECHANICS AND DYSPNEA AFTER LUNG TRANSPLANTATION FOR CHRONIC AIR-FLOW OBSTRUCTION

Single lung transplantation (SLT) is widely used to treat advanced chr onic airflow obstruction (CAO). During exercise the native lung should increase end-expiratory lung volume (EELV) and result in a different respiratory sensation compared with double lung transplantation (DLT). Eight SLT recipients and 12 DLT recipients demonstrated a similar max imal work load and achieved Vover dotO(2) Vover dot(max)/MW was 67.2 /- 4.0% in SLT recipients and 48.5 +/- 3.6% in DLT recipients (p = 0.0 03). All SLT recipients demonstrated an increase in EELV during exerci se, which was seen in only three of 12 DLT recipients. The change in a bsolute EELV from rest to peak exercise was different between SLT reci pients (+0.37 +/- 0.10 L) and DLT recipients (-0.10 +/- 0.06, p = 0.00 02). Tidal flow volume loop analysis demonstrated encroachment of the expiratory limb in four of seven SLT recipients but in only one of 12 DLT recipients. A lesser peak breathlessness in DLT recipients approac hed statistical significance (p = 0.051), although the relation of res piratory sensation versus Vover dotE or Vover dotO(2)% predicted did n ot differ between the two groups. EELV increases in SLT recipients at peak exercise, although overall aerobic response is preserved and resp iratory sensation is similar.