title: Pulmonary function after complete unilateral phrenic nerve transection.
abstract: OBJECTIVE
  The status of pulmonary function following phrenic nerve transfer surgery is still largely unknown because of the high degree of variability in the accessory phrenic nerve that may be involved. In the present study, pulmonary functions were assessed in patients before and after full-length phrenic nerve transfer surgery, in whom the phrenic nerve was severed at a location just before its entry into the diaphragm.
  
  
  METHODS
  Fifteen patients (average age 27.4 years) with complete brachial plexus palsy underwent full-length phrenic nerve transfer. The phrenic nerve was harvested from the thoracic cavity by means of video-assisted thoracic surgery and then transferred to the musculocutaneous nerve. Postoperative pulmonary functions were retrospectively analyzed. Patients underwent follow-up evaluation for 42 to 48 months; four patients were eventually lost to follow up. Although no patient experienced pulmonary problems following the surgery, all sustained varying degrees of diaphragmatic paralysis and elevation (for 1-1.5 intercostal spaces) on the surgically treated side as seen on chest x-ray films. Pulmonary functional parameters, including vital capacity, vital capacity in percentage of predicted values, residual volume, total lung capacity, forced vital capacity, and forced expiratory volume in 1 second, recovered to preoperative levels by 1 year postsurgery. In contrast, the postoperative maximal inspiratory pressure value was significantly decreased compared with the predicted values (average decrease approximately 20%) in all of the patients, even at 4 years after the surgery.
  
  
  CONCLUSIONS
  In young patients with healthy lung function, unilateral phrenic nerve transection surgery can cause unilateral diaphragmatic paralysis and reduce the inspiration muscle force; however, most pulmonary function parameters gradually recover to preoperative levels within 1 year.
authors.affiliation: Department of Hand Surgery, Hua-Shan Hospital, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Wen-Dong
authors.initials: WD
authors.lastname: Xu
authors.forename: Yu-Dong
authors.initials: YD
authors.lastname: Gu
authors.forename: Jing-Bo
authors.initials: JB
authors.lastname: Lu
authors.forename: Cong
authors.initials: C
authors.lastname: Yu
authors.forename: Cheng-Gang
authors.initials: CG
authors.lastname: Zhang
authors.forename: Jian-Guang
authors.initials: JG
authors.lastname: Xu
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001917:Brachial Plexus / Q000293:injuries / Q000601:surgery*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D016067:Nerve Transfer / Q000009:adverse effects* / Q000379:methods*; D010791:Phrenic Nerve / Q000601:surgery*; D012129:Respiratory Function Tests; D012133:Respiratory Paralysis / Q000209:etiology*; D012189:Retrospective Studies; D016896:Treatment Outcome