Protocol of a multicentre, prospective cohort study that evaluates cost-effectiveness of two perioperative care strategies for potential obstructive sleep apnoea in morbidly obese patients undergoing bariatric surgery

Perioperative management of Obstructive Sleep Apnoea: Present themes and future directions

PURPOSE OF REVIEW

Obstructive sleep apnoea (OSA) is an increasingly common pathology that all those involved in perioperative care will come across. Patients with the condition present a challenge at many stages along the perioperative journey, not least because many patients living with OSA are unaware of their diagnosis.Key interventions can be made pre, intra-, and postoperatively to improve outcomes. Knowledge of screening tools, diagnostic tests, and the raft of treatment options are important for anyone caring for these patients.

RECENT FINDINGS

Recent literature has highlighted the increasing complexity of surgical patients and significant underdiagnosis of OSA in this patient population. Work has demonstrated how and why patients with OSA are at a higher perioperative risk and that effective positive airways pressure (PAP) therapy can reduce these risks, alongside evidencing how best to optimise adherence to therapy, a key issue in OSA.

SUMMARY

OSA, and particularly undiagnosed OSA, presents a huge problem in the perioperative period. Perioperative PAP reduces the risk of postoperative complications but adherence remains an issue. Bespoke perioperative pathways should be developed to identify and optimise high risk patients, although at present evidence on how best to achieve this is lacking.

Obstructive sleep apnoea and perioperative medicine: a growing concern

Obstructive sleep apnoea represents a sizable public health and economic burden. Owing to rising obesity rates, the prevalence of obstructive sleep apnoea is increasing, and it is a condition that is significantly underdiagnosed. Exacerbated by the COVID-19 pandemic, the backlog of elective surgeries is also sizable and growing. A combination of these factors means that many patients due to have surgery will have obstructive sleep apnoea, either diagnosed or otherwise.

Patients with obstructive sleep apnoea have a significantly increased risk of operative complications, but the evidence base for optimum perioperative management of these patients is limited. This article reviews sleep apnoea, its prevalence and its impact on operative management and perioperative outcomes for patients. The evidence base for screening and treating undiagnosed obstructive sleep apnoea is also comprehensively assessed. Finally, a pathway to manage patients with possible undiagnosed obstructive sleep apnoea is proposed, and areas for further research identified.

Evaluation of CPAP adherence in bariatric patients diagnosed with obstructive sleep apnea: outcomes of a multicenter cohort study

Purpose

Obstructive sleep apnea (OSA) is highly prevalent but mostly undiagnosed in obese patients scheduled for bariatric surgery. To prevent cardiopulmonary complications, many clinics perform preoperative OSA screening. Consequently, adequate adherence to continuous positive airway pressure (CPAP) therapy is essential but challenging. We aimed to evaluate CPAP adherence and its influence on postoperative outcomes.

Methods

In a prospective multicenter cohort study, we compared different perioperative strategies for handling undiagnosed OSA in bariatric patients. In this subgroup analysis, patients newly diagnosed with OSA were compared to those with pre-existing OSA. We assessed inadequate CPAP adherence, defined as < 4 h/night, between the preoperative period and 6 months postoperative. Cardiopulmonary complications and (un)scheduled ICU admissions were also evaluated.

Results

In total, 272 patients with newly diagnosed OSA (67.4%) and 132 patients with pre-existing OSA (32.6%) were included. Before surgery, 41 newly diagnosed patients used CPAP inadequately, compared to 5 patients with pre-existing OSA (15% vs. 4%, p = 0.049). Six months after surgery, inadequate CPAP use increased to 73% for newly diagnosed patients and 39% for patients with pre-existing OSA, respectively (p < 0.001). Incidences of cardiopulmonary complications, scheduled, and unscheduled ICU admissions were similar in the two study groups (p = 0.600, p = 0.972, and p = 0.980, respectively).

Conclusion

Inadequate CPAP adherence is higher in bariatric patients newly diagnosed with OSA when compared to patients with pre-existing OSA. Strategies to increase CPAP adherence may be valuable when considering routine OSA screening and CPAP therapy in patients undergoing bariatric surgery. Further studies are needed to improve current guidelines on perioperative OSA management of obese patients.

Trial registration

POPCORN study, registered at Netherlands Trial Register, https://www.trialregister.nl/trial/6805. ID no: 6805.

Preoperative Assessment of Obstructive Sleep Apnea in Bariatric Patients Using Polysomnography or Polygraphy

BACKGROUND

Preoperative assessment of obstructive sleep apnea (OSA) in patients scheduled for bariatric surgery can be performed by in-laboratory polysomnography (PSG) or by portable polygraphy (PP) at home. We aimed to evaluate the association between PSG/PP, OSA diagnosis, and implementation of continuous positive airway pressure (CPAP) therapy.

METHODS

All patients who underwent bariatric surgery from 2015 to 2017 were retrospectively reviewed. Patients underwent preoperative PSG or PP, based on prevailing protocols or at the physician's discretion. Logistic regression analyses were performed to determine predictors of CPAP implementation. OSA-related postoperative complications were analyzed in both groups.

RESULTS

During the study period, 1464 patients were included. OSA was diagnosed in 79% of 271 patients undergoing PSG, compared to 64% of 1193 patients undergoing PP (p < 0.001), with median apnea-hypopnea index (AHI) of 15.8 and 7.7, respectively. CPAP treatment was initiated in 52% and 27% of patients, respectively, p < 0.001. Predictors (with adjusted odds ratio) in multivariate regression analysis for CPAP implementation were as follows: male gender (5.15), BMI ≥ 50 (3.85), PSG test (2.74), hypertension (2.38), and age ≥ 50 (1.87). OSA-related complications did not differ between groups (p = 0.277).

CONCLUSION

Both PSG and PP are feasible options for preoperative OSA assessment in bariatric patients. When PP is performed, some underdiagnosis may occur as cases of mild OSA may be missed. However, clinically relevant OSA is detected by both diagnostic tools. No difference in OSA-related complications was found. PP is a safe, less invasive option and can be considered as a suitable measure for OSA assessment in this population.