Perioperative Complications in Obstructive Sleep Apnea Patients

Diagnostic Value of Neutrophil to Lymphocyte Ratio for Assessing Obstructive Sleep Apnea Risk in Surgical Patients

PURPOSE

Obstructive sleep apnea (OSA) is an important risk factor leading to perioperative complications in surgical patients. Neutrophil-to-lymphocyte ratio (NLR) is an important biomarker of increasing interest in recent years, and is used in the determination of systemic inflammatory response.

DESIGN

The aim of this study was to evaluate the risk of OSA and the relationship between OSA risk and NLR in surgical patients.

METHODS

The study was conducted in a tertiary care hospital between November 2021 and May 2022. The cross-sectional study included 604 patients who underwent surgery. OSA risk was evaluated with the STOP-Bang questionnaire in the preoperative evaluation in all patients. NLR was calculated as the ratio of neutrophil count to lymphocyte count.

FINDINGS

According to the STOP-Bang questionnaire, 62.3% of the patients had a high risk of OSA in the preoperative period. Patients who were male, elderly, obese, had hypertension, diabetes, chronic lung disease, and heart disease and polypharmacy were at greater risk of OSA. Patients at high risk of OSA had significantly higher NLR than patients at low risk of OSA. (2.65 vs 2.92, P.ß=.ß.024). NLR of 2.40 or higher predicted OSA risk with 58.8% sensitivity and 51.0% specificity (AUC.ß=.ß0.561) CONCLUSIONS: Most patients who were to undergo surgery had a high risk of OSA. NLR was higher in patients at high risk of OSA. Although the diagnostic efficacy is not high, NLR can be used to detect high OSA risk because it is a low-cost and easy to obtain biomarker.

The potential link between obstructive sleep apnea and postoperative neurocognitive disorders: current knowledge and possible mechanisms

PURPOSE

This narrative review examines the current evidence on whether obstructive sleep apnea (OSA) is associated with postoperative delirium (POD) and postoperative cognitive dysfunction (POCD). The mechanisms that could predispose OSA patients to these disorders are also explored.

SOURCE

Relevant literature was identified by searching for pertinent terms in Medline®, Pubmed, ScopusTM, and Google scholar databases. Case reports, abstracts, review articles, original research articles, and meta-analyses were reviewed. The bibliographies of retrieved sources were also searched to identify relevant papers.

PRINCIPAL FINDINGS

Seven studies have investigated the association between OSA and POD, with mixed results. No studies have examined the potential link between OSA and POCD. If these relationships exist, they could be mediated by several mechanisms, including increased neuroinflammation, blood-brain barrier breakdown, cerebrovascular disease, Alzheimer's disease neuropathology, disrupted cerebral autoregulation, sleep disruption, sympathovagal imbalance, and/or disrupted brain bioenergetics.

CONCLUSION

There is very limited evidence that OSA plays a role in postoperative neurocognitive disorders because few studies have been conducted in the perioperative setting. Additional perioperative prospective observational cohort studies and randomized controlled trials of sleep apnea treatment are needed. These investigations should also assess potential underlying mechanisms that could predispose patients with OSA to postoperative neurocognitive disorders. This review highlights the need for more research to improve postoperative neurocognitive outcomes for patients with OSA.

Patient Selection for Adult Ambulatory Surgery: A Narrative Review

With migration of medically complex patients undergoing more extensive surgical procedures to the ambulatory setting, selecting the appropriate patient is vital. Patient selection can impact patient safety, efficiency, and reportable outcomes at ambulatory surgery centers (ASCs). Identifying suitability for ambulatory surgery is a dynamic process that depends on a complex interplay between the surgical procedure, patient characteristics, and the expected anesthetic technique (eg, sedation/analgesia, local/regional anesthesia, or general anesthesia). In addition, the type of ambulatory setting (ie, short-stay facilities, hospital-based ambulatory center, freestanding ambulatory center, and office-based surgery) and social factors, such as availability of a responsible individual to take care of the patient at home, can also influence patient selection. The purpose of this review is to present current best evidence that would provide guidance to the ambulatory anesthesiologist in making an informed decision regarding patient selection for surgical procedures in freestanding ambulatory facilities.

Critical Analysis of Guidelines for Providing Sedation to Patients Undergoing Gastrointestinal Endoscopy Procedures

In spite of growing numbers of gastrointestinal endoscopic procedures performed under deep sedation, guidelines are lacking. Hypoxemia and aspiration continue to be the main source of morbidity. Anesthesia providers have tried to address these concerns by modifying their technique and employing newer or improvised devices. In addition, preprocedural evaluation poses many challenges. In many centers, workload pressures determine the time available to perform such an evaluation. A comprehensive history and examination similar to a major surgical procedure is often not possible. As a result, a focused history and examination is essential. This should be followed by an appropriate explanation of risks before obtaining consent. A plan should be in place to manage complications such as aspiration. This paper provides a succinct review of the above aspects.