Phrenic Nerve Dysfunction After Heart-lung and Lung Transplantation

Background: Phrenic nerve dysfunction (PND) is a well-known complication after cardiac surgery, but reports on its incidence and consequences after heart-lung and lung transplantation are scarce.

Methods: The incidence and consequences (ventilator days and intensive-care unit length of stay [ICU LOS]) of PND were studied by retrospective chart review of 27 heart-lung (HLTx) and 111 lung (LTx) transplantations performed from July 1991 to June 2001 at the Leuven University Hospital, Leuven, Belgium. On clinical suspicion of diaphragmatic dysfunction, nerve conduction studies were performed, which were completed with a needle electromyogram (EMG) of the diaphragm when the conduction study was non-conclusive.

Results: The incidence of PND in 21 evaluable HLTx recipients was 42.8% (9 of 21 patients), resulting in significantly more ventilator days for PND patients (37.6 +/- 36.3 days vs 5.3 +/- 3 days; p < 0.05) and a prolonged ICU LOS (46.8 +/- 33 vs 9.8 +/- 4.9 days; p < 0.05). In the 97 evaluable LTx patients, 9.3% (9 of 97 patients) developed PND. This resulted in more ventilator days for the PND group (30.6 +/- 14.8 days vs non-PND 7.9 +/- 14.8 days. p < 0.05) and a longer ICU LOS (PND 37.8 +/- 18.7 days vs non-PND 12.1 +/- 17.8 p < 0.05). Needle EMG of the diaphragm revealed denervation in 1 HLTx and 5 LTx patients. In LTx patients sustaining PND more tracheostomies were performed (44.4% vs 4.5% for non-PND patients p < 0.005). Eight of 9 LTx patients with PND had sequential single-lung transplantation.

Conclusions: PND represents an important clinical problem after HLTx and LTx and has a considerable influence on both number of ventilator days and ICU resource utilization.