title: Incidence and natural history of phrenic neuropathy occurring during open heart surgery.
abstract: OBJECTIVE
  To study the incidence of phrenic neuropathy following coronary artery bypass grafting and determine long-term outcome.
  
  
  METHODS
  Prospective observational.
  
  
  METHODS
  Surgical ICU in a university hospital, out-patient follow-up.
  
  
  METHODS
  Ninety-two consecutive patients undergoing open heart surgery.
  
  
  METHODS
  None.
  
  
  METHODS
  Chest radiographs (CXR) 48 to 72 h post-operatively, ultrasonography of diaphragm, phrenic nerve conduction studies, diaphragmatic electromyogram, each repeated every 1 to 3 months until normal.
  
  
  RESULTS
  Seventy-eight of 92 (78 percent) patients had abnormal radiographs, 42 of 78 (54 percent) with abnormal CXRs had abnormal diaphragm motion, 24 of 42 (57 percent) with abnormal motion had phrenic neuropathy. Patients with normal diaphragm motion improved faster than those without; patients with normal nerve conduction (and abnormal motion) improved faster than those with abnormal nerve conduction.
  
  
  CONCLUSIONS
  Phrenic neuropathy is relatively common if sensitive tests are utilized for diagnosis. Nerve conduction studies can predict duration of morbidity. Most patients have low morbidity and recover fully. Abnormal diaphragm motion alone is not diagnostic of phrenic nerve injury.
authors.affiliation: Montefiore Hospital, Pittsburgh.
authors.forename: M A
authors.initials: MA
authors.lastname: DeVita
authors.forename: L R
authors.initials: LR
authors.lastname: Robinson
authors.forename: J
authors.initials: J
authors.lastname: Rehder
authors.forename: B
authors.initials: B
authors.lastname: Hattler
authors.forename: C
authors.initials: C
authors.lastname: Cohen
mesh_terms: D000368:Aged; D016009:Chi-Square Distribution; D001026:Coronary Artery Bypass / Q000009:adverse effects* / Q000706:statistics & numerical data; D003964:Diaphragm / Q000000981:diagnostic imaging; D016002:Discriminant Analysis; D004576:Electromyography; D005260:Female; D006801:Humans; D015994:Incidence; D007431:Intraoperative Complications / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D008168:Lung / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D009431:Neural Conduction; D010414:Pennsylvania / Q000453:epidemiology; D010791:Phrenic Nerve / Q000293:injuries* / Q000502:physiology; D011859:Radiography; D012307:Risk Factors; D016896:Treatment Outcome; D014463:Ultrasonography