Background: It's not uncommon for people to suffer obstructive sleep apnea syndrome (OSAS); 2%-25% of the general population are affected. However, OSAS is common in those who have undergone elective surgery. Patients with collapsing upper airway have an increased risk of surgical complications when under sedation and/or anesthesia. To effectively treat individuals with OSAS, it's critical to rapidly identify them. Objective: In this review, the epidemiology of OSAS in postoperative patients was examined. We emphasized the significance of anaesthesia, sedation, opioids, while describing why these patients have a higher postoperative complications' risk. Further, we addressed the preoperative identification and perioperative management of these individuals. Methods: Research was carried out through PubMed, Google scholar and Science direct using the terms OSAS, Perioperative complications, Respiratory problems, and continuous positive airway pressure (CPAP). References from relevant literature, including all identified research and reviews, were evaluated (only studies published between July 2003 and January 2022 were included). There were no reliable sources of interpretation for documents written in any language other than English. All but the most important scientific papers had been omitted: not available as a complete written text such as a transcript of a conversation or a formal paper such as a conference abstract or thesis. Conclusion: Opioids, sedation, and anesthesia have been proven to aggravate sleep apnea during the perioperative phase, which may raise the risk of perioperative problems. It is essential to identify these individuals before surgery in order to take the necessary precautions during their perioperative care.