Obstructive sleep apnoea and open heart surgery: a review of its incidence and impact to patients

Background: Obstructive sleep apnea (OSA) is a serious health disorder which contributes to cardiovascular complications, decreased work productivity, automobile accidents, and death. This condition is characterized by a temporary cessation of breathing resulting due to upper airway closure during a person's sleep. Strain to the heart caused by this repetitive hypoxic insult can lead to postoperative complications for patients undergoing heart surgery. Recognizing cardiac surgical patients with OSA is important. Early recognition and intervention such as use of BiPAP device can reduce the postoperative complications due to OSA. Methods: The aim of this study is to identify the incidence of unrecognized OSA in cardiac surgical patients. This is a retrospective analysis of a prospective data of the study which was done between July 2012 and July 2013 in University Malaya Medical Center. All patients undergoing elective cardiac surgery were recruited and the demographic data, questionnaire and the portable sleep study results were obtained. Patients were followed up till 30 days to record any complications. Data were entered in SPSS version 17 and analysis was done. Results: The incidence of OSA was 61.4% and 43.5% were moderate to severe OSA. There was male predominance of OSA (79%) with a mean age of 60 years. OSA subjects had shorter inter-incisor distance (4.18 +/- 0.6 cm) and larger waistline (94.1 +/- 12.1 cm). The STOP-Bang questionnaire has a sensitivity of 75.8% in predicting apnoa-hypopnea index (AHI) >= 5/hour. Conclusions: OSA can be diagnosed with a simple screening questionnaire and a bedside portable sleep study. Cardiac patients diagnosed with OSA can be pre-emptively given extra attention in managing their postoperative care.