Diaphragmatic paralysis, chronic obstructive pulmonary disease, and coronary bypass surgery

Purpose: The effect of phrenic nerve injury (PNI), occurring during CABG in patients (pts) with significant COPD, was evaluated. Methods: Over a 40 months, 1303 pts underwent primary CABG; 67 (5.14%) had significant COPD, of whom 29 (43.3%) suffered PNI (Grp I). These were matched to groups of 29 CABG pts with COPD, without PNI (Grp II), without COPD, with PNI (Grp III), and without COPD or PNI (Grp IV). Groups were compared for acute and mid-term morbidity, and mortality. Results: There were no significant differences in preoperative and operative factors among the groups. Postoperatively, Grp I had longer total hospitalization (I-11.7; II- 7.8; III- 7.8; IV-6 days; P<0.0001) and ICU stay (I-3.6; II- 2.2; III- 2.1; IV- 1.2 days; P<0.002). Mean follow-up was 32.8 (range 7-48) months. Grp I had more hospital readmissions (I- 78; II- 50; III-61; IV- 28; P<0.007), lower cumulative survival (I-60.6%; II- 93%; III- 96.8%; IV-100%; P<0.0015) and reduced quality of life compared with preoperative status (P<0.049). Conclusions: In pts with COPD, PNI during CABG has a major negative impact on immediate and midterm results. Clinical Implications: When CABG is performed in pts with COPD, these efforts should be made to avoid PNI: avoidance of topical iced slush saline, restricted use of IMA and avoidance of extensive mobilization of the IMA.