Dynamic hyperinflation after bronchial lung volume reduction: An expected effect or perhaps a preoperative test for selection?

Introduction In our center we have treated with bronchial valves (Zephyr model) 35 patients suffering from advanced emphysema, with variable results. This is a preliminary report that refers to 14 patients who were studied for the presence of dynamic hyperinflation, evaluating the inspiratory capacity (IC) before and at the end of a submaximal effort (ΔIC). Methods After assessing the whole group we analyzed two different subgroups on the basis of dynamic hyperinflation. Group1 included 10 patients with dynamic hyperinflation (ΔIC reduced>10%); group2 included 4 patients without dynamic hyperinflation (ΔIC reduced<10%). Results at 6 month are in the tables Conclusion The dynamic hyperinflation seems reduced after BLVR in the whole group (ΔIC from -24% to -19%; (Table 1), but this data is not statistically significant; interestingly 10 patients in group 1 seem to have better results compared to 4 patients in group 2; in particular they have a better improvement of RV and ΔIC (Table 2). These preliminary data seem to propose dynamic hyperinflation as one of selection criteria for BLVR. A larger group of patients need to be examined to verify these data. Table 1: the whole group;*p<0.05 All 14 pts FEV1ml RVml 6MWDmt Delta-IC Pre-BLVR 1030+/-430 4630+/-1120 342+/-100 -24% Post-BLVR 1160+/-431 3970+/-1000* 373 +/-97 -19 Tab.2: gr.1, dynamic hyperinflation; *p<0.05; gr.2, no dynamic hyperinflation Gr1:10 pts FEV1ml RVml 6MWDmt Delta-IC Pre-BLVR 1040+/-360 4520+/-639 347+/-109 -31% Post-BLVR 1190+/- 378 3800+/-754* 385+/-89 -23%improv. Gr2-4 pts FEV1ml RVml 6MWDm Delta-IC Pre-BLVR 1030+/-550 5020+/-2000 335+/-87 -7% Post-BLVR 1080+/-603 4570+/- 1580 348+/-124 -8% unchanged