title: Follow-up with objective and subjective tests of the sleep characteristics of patients after cardiac surgery.
abstract: BACKGROUND
  The purpose of this study was to investigate the changes in sleep characteristics in patients who underwent coronary artery bypass grafting (CABG) surgery, using both subjective and objective tests in the early (preoperative) and late (postoperative) periods.
  
  
  RESULTS
  Forty-five patients who underwent CABG and did not previously have any sleep disturbance were evaluated by subjective and objective sleep parameters during a consecutive 3-5-day preoperative examination, during a consecutive 5-8-day period in the 1st postoperative week, and during consecutive 5-8-day periods in the 1st and 2nd postoperative months. The Pittsburgh Index and Epworth Sleepiness Scale values, sleep latency, napping episodes, total napping period, duration of wakefulness after sleep onset and fragmentation index values were significantly increased; however, Maintenance of Wakefulness Test lengths, total sleep time and sleep efficiency were significantly decreased in the 1st postoperative week. All of these were the same in the 1st postoperative month and differences were not statistically different from the preoperative period. None of the sleep parameters in the 2nd postoperative month differed from the values obtained in the preoperative period.
  
  
  CONCLUSIONS
  The cause of sleeplessness after CABG surgery may be temporary deterioration of circulation in the centers of the brain stem and hypothalamus that control sleep and awakening. Improvement of the circulation in these centers a few months after the operation helps to regain sleep control, and thus sleep disturbances disappear.
authors: Department of Neurology, Celal Bayar University School of Medicine, Manisa, Turkey.
authors: Hikmet
authors: H
authors: Yilmaz
authors: Ihsan
authors: I
authors: Iskesen
mesh_terms: D000328:Adult; D000368:Aged; D000758:Anesthesia / Q000009:adverse effects; D001933:Brain Stem / Q000098:blood supply; D016022:Case-Control Studies; D002560:Cerebrovascular Circulation / Q000502:physiology; D002940:Circadian Rhythm / Q000502:physiology; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007031:Hypothalamus / Q000098:blood supply; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012890:Sleep / Q000502:physiology; D012893:Sleep Wake Disorders / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*