Postoperative Critical Events Associated With Obstructive Sleep Apnea: Results From the Society of Anesthesia and Sleep Medicine Obstructive Sleep Apnea Registry

Adverse events in patients with obstructive sleep apnea undergoing procedural sedation in ambulatory settings: An updated systematic review and meta-analysis

OBJECTIVE

Patients with obstructive sleep apnea (OSA) may be at increased risk for adverse events during procedural sedation, however, there remains a gap in the literature quantifying these risks. This systematic review and meta-analysis aimed to evaluate the risk of peri-procedural adverse events in OSA patients undergoing procedural sedation in ambulatory settings, compared to those without OSA.

METHODS

Four databases were systematically searched for studies published from January 1, 2011 to January 4, 2024. The inclusion criteria were: adult patients with OSA undergoing procedural sedation in ambulatory settings, peri-procedural adverse events reported, and control group included. The primary outcome was the incidence of peri-procedural adverse events amongst patients with vs without OSA.

RESULTS

Nineteen studies (27,973 patients) were included. The odds of respiratory adverse events were significantly increased for patients with OSA (OR 1.65, 95 % CI 1.03-2.66, P = 0.04). Furthermore, the odds of requiring an airway maneuver/intervention were significantly greater for patients with OSA (OR 3.28, 95 % CI 1.43-7.51, P = 0.005). The odds of cardiovascular adverse events were not significantly increased for patients with OSA.

CONCLUSION

Patients with OSA undergoing procedural sedation in ambulatory settings had 1.7-fold greater odds of respiratory adverse events and 3.3-fold greater odds of requiring airway maneuvers/interventions.

The knowledge profile, attitudes, and perioperative management of Chinese anesthesiologists towards patients with obstructive sleep apnea: a cross-sectional survey

BACKGROUNDS

Obstructive sleep apnea syndrome (OSA) is increasingly encountered by anesthesiologists in clinical practice. However, research on managing these patients among anesthesiologists in China is scarce. This study aims to investigate the knowledge, attitudes, and perioperative management strategies for OSA patients among Chinese anesthesiologists.

METHODS

In this cross-sectional study, anesthesiologists from various hospitals across China were invited to complete a thirty-eight-item online questionnaire survey between October 1 and November 1, 2022. The Obstructive Sleep Apnea Knowledge and Attitude (OSAKA) scale was utilized to measure their knowledge and attitudes.

RESULTS

A total of 470 valid participants were recruited for this research, resulting in a valid response rate of 73.3%. (1) While the majority of participants acknowledged the importance of identifying OSA during perioperative management, only 58.3% felt confident in managing OSA patients; (2) Anesthesiologists with higher professional titles and longer work experience exhibited greater confidence in managing OSA patients; (3) Just under half of the participants were familiar with the STOP-Bang and Berlin questionnaires. Anesthesiologists with over 20 years of work experience were more likely to use the STOP-Bang and Berlin questionnaires compared to those with less than 10 years of work experience (OR = 3.166, P < 0.001); (4) 71.1% of participants expressed approval regarding the preparation of sugammadex for muscle relaxation reversal, while only 32.8% approved the safety of opioid use for postoperative analgesia in OSA patients.

CONCLUSION

The study displayed that Chinese anesthesiologists have inadequate knowledge and perioperative management of OSA than expected. However, they have positive attitudes towards the assessment and management of OSA. The study highlights the need for high-quality training to identify and manage OSA among Chinese anesthesiologists.

Perioperative adverse events in adult patients with obstructive sleep apnea undergoing ambulatory surgery: An updated systematic review and meta-analysis

BACKGROUND

The suitability of ambulatory surgery for patients with obstructive sleep apnea (OSA) remains controversial. This systematic review and meta-analysis aimed to evaluate the odds of perioperative adverse events in patients with OSA undergoing ambulatory surgery, compared to patients without OSA.

METHODS

Four electronic databases were searched for studies published between January 1, 2011 and July 11, 2023. The inclusion criteria were: adult patients with diagnosed or high-risk of OSA undergoing ambulatory surgery; perioperative adverse events; control group included; general and/or regional anesthesia; and publication on/after February 1, 2011. We calculated effect sizes as odds ratios using a random effects model, and additional sensitivity analyses were conducted.

RESULTS

Seventeen studies (375,389 patients) were included. OSA was associated with an increased odds of same-day admission amongst all surgery types (OR 1.94, 95% CI 1.46-2.59, I2:79%, P < 0.00001, 11 studies, n = 347,342), as well as when only orthopedic surgery was considered (OR 2.68, 95% CI 2.05-3.48, I2:41%, P < 0.00001, 6 studies, n = 132,473). Three studies reported that OSA was strongly associated with prolonged post anesthesia care unit (PACU) length of stay (LOS), while one study reported that the association was not statistically significant. In addition, four studies reported that OSA was associated with postoperative respiratory depression/hypoxia, with one large study on shoulder arthroscopy reporting an almost 5-fold increased odds of pulmonary compromise, 5-fold of myocardial infarction, 3-fold of acute renal failure, and 5-fold of intensive care unit (ICU) admission.

CONCLUSIONS

Ambulatory surgical patients with OSA had almost two-fold higher odds of same-day admission compared to non-OSA patients. Multiple large studies also reported an association of OSA with prolonged PACU LOS, respiratory complications, and/or ICU admission. Clinicians should screen preoperatively for OSA, optimize comorbidities, adhere to clinical algorithm-based management perioperatively, and maintain a high degree of vigilance in the postoperative period.

Evidence-based interventions to improve sleep quality after thoracic surgery:A retrospective analysis of clinical studies

OBJECTIVE

To investigate and rank the evidence for the efficacy of interventions in improving sleep quality after cardiac surgery using comprehensive comparisons.

BACKGROUND

Clinical evidence suggests that over 80 % of adult cardiac surgery patients experience sleep disturbances during the first week postoperatively. While certain interventions have been shown to improve post-thoracic surgery sleep quality, a systematic description of the effects of these varied interventions is lacking.

METHODS

This systematic search was conducted across PubMed, Web of Science, Cochrane, Embase, and CINAHL databases to collate all published randomized clinical trials as evidence. Two researchers independently extracted pertinent information from eligible trials and assessed the quality of included studies. Based on statistical heterogeneity, traditional meta-analysis using fixed or random-effects models was employed to assess the efficacy of interventions, and a Frequentist network meta-analysis using a consistency model was conducted to rank the effectiveness of intervention protocols.

RESULTS

Our review incorporated 37 articles (n = 3569), encompassing 46 interventions, including 9 reports on pharmacological interventions (24.3 %), 28 on non-pharmacological interventions (75.7 %), and 5 on anesthetic management interventions (13.5 %). The analysis indicated the efficacy of Benson's relaxation technique, Progressive muscle relaxation, Education, Aromatherapy, Acupressure, Massage, and Eye masks in enhancing postoperative sleep quality. Specifically, Benson's relaxation technique (cumulative ranking curve area: 0.80; probability: 98.3 %) and Acupressure (cumulative ranking curve area: 0.96; probability: 58.3 %) were associated with the highest probability of successfully improving postoperative sleep quality, while Progressive muscle relaxation (cumulative ranking curve area: 0.70; probability: 35.2 %) and Eye masks (cumulative ranking curve area: 0.81; probability: 78.8 %) were considered secondary options. Eye masks and Massage significantly reduced postoperative sleep latency, with Eye masks (cumulative ranking curve area: 0.82; probability: 51.0 %) being most likely to enhance sleep quality postoperatively, followed by Massage (cumulative ranking curve area: 0.60; probability: 27.2 %). Education, Music, Massage, Eye masks, and Handholding were effective in alleviating pain intensity, with Education being most likely to successfully reduce postoperative pain (cumulative ranking curve area: 0.92; probability: 54.3 %), followed by Music (cumulative ranking curve area: 0.91; probability: 54 %).

CONCLUSIONS

Our findings can be utilized to optimize strategies for managing post-thoracic surgery sleep disturbances and to develop evidence-based approaches for this purpose. Benson's relaxation technique, Progressive muscle relaxation, Education, Aromatherapy, Acupressure, Massage, and Eye masks significantly improve sleep quality in postoperative patients. KEY: disorders of initiating and maintaining sleep, sleep wake disorders, thoracic surgical procedures, cardiac surgical procedures, sleep quality, pain, network meta-analysis.

Obstructive Sleep Apnea and Risk of Postoperative Complications after Non-Cardiac Surgery

Obstructive sleep apnea (OSA), a common sleep disorder, poses significant challenges in perioperative management due to its complexity and multifactorial nature. With a global prevalence of approximately 22.6%, OSA often remains undiagnosed, and increases the risk of cardiac and respiratory postoperative complications. Preoperative screening has become essential in many institutions to identify patients at increased risk, and experts recommend proceeding with surgery in the absence of severe symptoms, albeit with heightened postoperative monitoring. Anesthetic and sedative agents exacerbate upper airway collapsibility and depress central respiratory activity, complicating intraoperative management, especially with neuromuscular blockade use. Additionally, OSA patients are particularly prone to opioid-induced respiratory depression, given their increased sensitivity to opioids and heightened pain perception. Thus, regional anesthesia and multimodal analgesia are strongly advocated to reduce perioperative complication risks. Postoperative care for OSA patients necessitates vigilant monitoring and tailored management strategies, such as supplemental oxygen and Positive Airway Pressure therapy, to minimize cardiorespiratory complications. Health care institutions are increasingly focusing on enhanced monitoring and resource allocation for patient safety. However, the rising prevalence of OSA, heterogeneity in disease severity, and lack of evidence for the efficacy of costly perioperative measures pose challenges. The development of effective screening and monitoring algorithms, alongside reliable risk predictors, is crucial for identifying OSA patients needing extended postoperative care. This review emphasizes a multidimensional approach in managing OSA patients throughout the perioperative period, aiming to optimize patient outcomes and minimize adverse outcomes.

Introduction of a Post-Anaesthesia Care Unit in a Teaching Hospital Is Associated with a Reduced Length of Hospital Stay in Noncardiac Surgery: A Single-Centre Interrupted Time Series Analysis

BACKGROUND

A post-anaesthesia care unit (PACU) may improve postoperative care compared with intermediate care units (IMCU) due to its dedication to operative care and an individualized duration of postoperative stay. The effects of transition from IMCU to PACU for postoperative care following intermediate to high-risk noncardiac surgery on length of hospital stay, intensive care unit (ICU) utilization, and postoperative complications were investigated.

METHODS

This single-centre interrupted time series analysis included patients undergoing eleven different noncardiac surgical procedures associated with frequent postoperative admissions to an IMCU or PACU between January 2018 and March 2019 (IMCU episode) and between October 2019 and December 2020 (PACU episode). Primary outcome was hospital length of stay, secondary outcomes included postoperative complications and ICU admissions.

RESULTS

In total, 3300 patients were included. The hospital length of stay was lower following PACU admission compared to IMCU admission (IMCU 7.2 days [4.2-12.0] vs. PACU 6.0 days [3.6-9.1]; p < 0.001). Segmented regression analysis demonstrated that the introduction of the PACU was associated with a decrease in hospital length of stay (GMR 0.77 [95% CI 0.66-0.91]; p = 0.002). No differences between episodes were detected in the number of postoperative complications or postoperative ICU admissions.

CONCLUSIONS

The introduction of a PACU for postoperative care of patients undergoing intermediate to high-risk noncardiac surgery was associated with a reduction in the length of stay at the hospital, without increasing postoperative complications.

Considerations for Functional Nasal Surgery in the Obstructive Sleep Apnea Population

Obstructive sleep apnea (OSA) and nasal obstruction are common in the general population and frequently treated by otolaryngologists and facial plastic surgeons. Understanding the appropriate pre-, peri-, and postoperative management of OSA patients undergoing functional nasal surgery is important. OSA patients should be appropriately counseled in the preoperative period on their increased anesthetic risk. In OSA patients who are continuous positive airway pressure (CPAP) intolerant, the role of drug-induced sleep endoscopy should be discussed with the patient, and depending on the surgeon's practice may prompt referral to a sleep specialist. Should multilevel airway surgery be indicated, it can safely be performed in most OSA patients. Surgeons should communicate with the anesthesiologist regarding an airway plan given this patient population's higher propensity for having a difficult airway. Given their increased risk of postoperative respiratory depression, extended recovery time should be given to these patients and the use of opioids as well as sedatives should be minimized. During surgery, one can consider using local nerve blocks to reduce postoperative pain and analgesic use. After surgery, clinicians can consider opioid alternatives such as nonsteroidal anti-inflammatory agents. Neuropathic agents, such as gabapentin, require further research in their indications for managing postoperative pain. CPAP is typically held for a period of time after functional rhinoplasty. The decision on when to restart CPAP should be individualized to the patient based on their comorbidities, OSA severity, and surgical maneuvers performed. More research would provide further guidance in this patient population to shape more specific recommendations regarding their perioperative and intraoperative course.

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.

Day-surgery adult patients with obesity and obstructive sleep apnea: Current controversies and concerns

Obesity and obstructive sleep apnea are considered independent risk factors that can adversely affect perioperative outcomes. A combination of these two conditions in the ambulatory surgery patient can pose significant challenges for the anesthesiologist. Nevertheless, these patients should not routinely be denied access to ambulatory surgery. Instead, patients should be appropriately optimized. Anesthesiologists and surgeons must work together to implement fast-track anesthetic and surgical techniques that will ensure successful ambulatory outcomes.

Preoperative risk evaluation and perioperative management of patients with obstructive sleep apnea: a narrative review

Obstructive sleep apnea (OSA) is a common sleep-breathing disorder associated with significant comorbidities and perioperative complications. This narrative review is aimed at comprehensively overviewing preoperative risk evaluation and perioperative management strategies for patients with OSA. OSA is characterized by recurrent episodes of upper airway obstruction during sleep leading to hypoxemia and arousal. Anatomical features, such as upper airway narrowing and obesity, contribute to the development of OSA. OSA can be diagnosed based on polysomnography findings, and positive airway pressure therapy is the mainstay of treatment. However, alternative therapies, such as oral appliances or upper airway surgery, can be considered for patients with intolerance. Patients with OSA face perioperative challenges due to difficult airway management, comorbidities, and effects of sedatives and analgesics. Anatomical changes, reduced upper airway muscle tone, and obesity increase the risks of airway obstruction, and difficulties in intubation and mask ventilation. OSA-related comorbidities, such as cardiovascular and respiratory disorders, further increase perioperative risks. Sedatives and opioids can exacerbate respiratory depression and compromise airway patency. Therefore, careful consideration of alternative pain management options is necessary. Although the association between OSA and postoperative mortality remains controversial, concerns exist regarding adverse outcomes in patients with OSA. Understanding the pathophysiology of OSA, implementing appropriate preoperative evaluations, and tailoring perioperative management strategies are vital to ensure patient safety and optimize surgical outcomes.

The impact of semi-upright position on severity of sleep disordered breathing in patients with obstructive sleep apnea: a two-arm, prospective, randomized controlled trial

BACKGROUND

The severity of sleep-disordered breathing is known to worsen postoperatively and is associated with increased cardio-pulmonary complications and increased resource implications. In the general population, the semi-upright position has been used in the management of OSA. We hypothesized that the use of a semi-upright position versus a non-elevated position will reduce postoperative worsening of OSA in patients undergoing non-cardiac surgeries.

METHODS

This study was conducted as a prospective randomized controlled trial of perioperative patients, undergoing elective non-cardiac inpatient surgeries. Patients underwent a preoperative sleep study using a portable polysomnography device. Patients with OSA (apnea hypopnea index (AHI) > 5 events/hr), underwent a sleep study on postoperative night 2 (N2) after being randomized into an intervention group (Group I): semi-upright position (30 to 45 degrees incline), or a control group (Group C) (zero degrees from horizontal). The primary outcome was postoperative AHI on N2. The secondary outcomes were obstructive apnea index (OAI), central apnea index (CAI), hypopnea index (HI), obstructive apnea hypopnea index (OAHI) and oxygenation parameters.

RESULTS

Thirty-five patients were included. Twenty-one patients were assigned to the Group 1 (females-14 (67%); mean age 65 ± 12) while there were fourteen patients in the Group C (females-5 (36%); mean age 63 ± 10). The semi-upright position resulted in a significant reduction in OAI in the intervention arm (Group C vs Group I postop AHI: 16.6 ± 19.0 vs 8.6 ± 11.2 events/hr; overall p = 0.01), but there were no significant differences in the overall AHI or other parameters between the two groups. Subgroup analysis of patients with "supine related OSA" revealed a decreasing trend in postoperative AHI with semi-upright position, but the sample size was too small to evaluate statistical significance.

CONCLUSION

In patients with newly diagnosed OSA, the semi-upright position resulted in improvement in obstructive apneas, but not the overall AHI.

TRIAL REGISTRATION

This trial was retrospectively registered in clinicaltrials.gov NCT02152202 on 02/06/2014.

Morphine and Hydromorphone Effects, Side Effects, and Variability: A Crossover Study in Human Volunteers

BACKGROUND

Balancing between opioid analgesia and respiratory depression continues to challenge clinicians in perioperative, emergency department, and other acute care settings. Morphine and hydromorphone are postoperative analgesic standards. Nevertheless, their comparative effects and side effects, timing, and respective variabilities remain poorly understood. This study tested the hypothesis that IV morphine and hydromorphone differ in onset, magnitude, duration, and variability of analgesic and ventilatory effects.

METHODS

The authors conducted a randomized crossover study in healthy volunteers. Forty-two subjects received a 2-h IV infusion of hydromorphone (0.05 mg/kg) or morphine (0.2 mg/kg) 1 to 2 weeks apart. The authors measured arterial opioid concentrations, analgesia in response to heat pain (maximally tolerated temperature, and verbal analog pain scores at discrete preset temperatures to determine half-maximum temperature effect), dark-adapted pupil diameter and miosis, end-expired carbon dioxide, and respiratory rate for 12 h after dosing.

RESULTS

For morphine and hydromorphone, respectively, maximum miosis was less (3.9 [3.4 to 4.2] vs. 4.6 mm [4.0 to 5.0], P < 0.001; median and 25 to 75% quantiles) and occurred later (3.1 ± 0.9 vs. 2.3 ± 0.7 h after infusion start, P < 0.001; mean ± SD); maximum tolerated temperature was less (49 ± 2 vs. 50 ± 2°C, P < 0.001); verbal pain scores at end-infusion at the most informative stimulus (48.2°C) were 82 ± 4 and 59 ± 3 (P < 0.001); maximum end-expired CO2 was 47 (45 to 50) and 48 mmHg (46 to 51; P = 0.007) and occurred later (5.5 ± 2.8 vs. 3.0 ± 1.5 h after infusion start, P < 0.001); and respiratory nadir was 9 ± 1 and 11 ± 2 breaths/min (P < 0.001), and occurred at similar times. The area under the temperature tolerance-time curve was less for morphine (1.8 [0.0 to 4.4]) than hydromorphone (5.4°C-h [1.6 to 12.1] P < 0.001). Interindividual variability in clinical effects did not differ between opioids.

CONCLUSIONS

For morphine compared to hydromorphone, analgesia and analgesia relative to respiratory depression were less, onset of miosis and respiratory depression was later, and duration of respiratory depression was longer. For each opioid, timing of the various clinical effects was not coincident. Results may enable more rational opioid selection, and suggest hydromorphone may have a better clinical profile.

EDITOR’S PERSPECTIVE

Society of Anesthesia and Sleep Medicine Position Paper on Patient Sleep During Hospitalization

This article addresses the issue of patient sleep during hospitalization, which the Society of Anesthesia and Sleep Medicine believes merits wider consideration by health authorities than it has received to date. Adequate sleep is fundamental to health and well-being, and insufficiencies in its duration, quality, or timing have adverse effects that are acutely evident. These include cardiovascular dysfunction, impaired ventilatory function, cognitive impairment, increased pain perception, psychomotor disturbance (including increased fall risk), psychological disturbance (including anxiety and depression), metabolic dysfunction (including increased insulin resistance and catabolic propensity), and immune dysfunction and proinflammatory effects (increasing infection risk and pain generation). All these changes negatively impact health status and are counterproductive to recovery from illness and operation. Hospitalization challenges sleep in a variety of ways. These challenges include environmental factors such as noise, bright light, and overnight awakenings for observations, interventions, and transfers; physiological factors such as pain, dyspnea, bowel or urinary dysfunction, or discomfort from therapeutic devices; psychological factors such as stress and anxiety; care-related factors including medications or medication withdrawal; and preexisting sleep disorders that may not be recognized or adequately managed. Many of these challenges appear readily addressable. The key to doing so is to give sleep greater priority, with attention directed at ensuring that patients' sleep needs are recognized and met, both within the hospital and beyond. Requirements include staff education, creation of protocols to enhance the prospect of sleep needs being addressed, and improvement in hospital design to mitigate environmental disturbances. Hospitals and health care providers have a duty to provide, to the greatest extent possible, appropriate preconditions for healing. Accumulating evidence suggests that these preconditions include adequate patient sleep duration and quality. The Society of Anesthesia and Sleep Medicine calls for systematic changes in the approach of hospital leadership and staff to this issue. Measures required include incorporation of optimization of patient sleep into the objectives of perioperative and general patient care guidelines. These steps should be complemented by further research into the impact of hospitalization on sleep, the effects of poor sleep on health outcomes after hospitalization, and assessment of interventions to improve it.

Obesity in Adults: Position Statement of Polish Association for the Study on Obesity, Polish Association of Endocrinology, Polish Association of Cardiodiabetology, Polish Psychiatric Association, Section of Metabolic and Bariatric Surgery of the Association of Polish Surgeons, and the College of Family Physicians in Poland

Obesity in adults and its complications are among the most important problems of public health. The search was conducted by using PubMed/MEDLINE, Cochrane Library, Science Direct, MEDLINE, and EBSCO databases from January 2010 to December 2022 for English language meta-analyses, systematic reviews, randomized clinical trials, and observational studies from all over the world. Six main topics were defined in the joint consensus statement of the Polish Association for the Study on Obesity, the Polish Association of Endocrinology, the Polish Association of Cardio-diabetology, the Polish Psychiatric Association, the Section of Metabolic and Bariatric Surgery of the Society of Polish Surgeons, and the College of Family Physicians in Poland: (1) the definition, causes and diagnosis of obesity; (2) treatment of obesity; (3) treatment of main complications of obesity; (4) bariatric surgery and its limitations; (5) the role of primary care in diagnostics and treatment of obesity and barriers; and (6) recommendations for general practitioners, regional authorities and the Ministry of Health. This statement outlines the role of an individual and the adequate approach to the treatment of obesity: overcoming obstacles in the treatment of obesity by primary health care. The approach to the treatment of obesity in patients with its most common complications is also discussed. Attention was drawn to the importance of interdisciplinary cooperation and considering the needs of patients in increasing the long-term effectiveness of obesity management.

Respiratory Monitoring after Opioid-Sparing Bariatric Surgery in Patients with Obstructive Sleep Apnea (OSA)

Introduction with Aim: Postoperative respiratory depression can complicate a patient’s recovery after surgery. A predictive score (PRODIGY) was recently proposed to evaluate the risk of opioid-induced postoperative respiratory depression. For the first time, we applied this score to a cohort of patients receiving bariatric surgery, stratified by Obstructive Sleep Apnea (OSA) status. In addition, we recorded continuous postoperative capnography to evaluate respiratory depression and apnea episodes (Respiratory Events, RE). Materials and Methods: The present study was approved by our IRB and comprised continuous surveillance of respiratory variables during postoperative recovery (in PACU) after robotic bariatric surgery. We utilized continuous capnography and pulse oximetry (Capnostream 35, Medtronic Inc., and Profox Respiratory Oximetry software). Preoperative preparation included OSA evaluation for all bariatric patients, additional sleep studies for severe OSA grades, and evaluation of risk for respiratory depression (low, intermediate, or high) using the published PRODIGY score. In addition, we evaluated patients by OSA status. All patients received multimodal intraoperative non-opioid anesthesia from the same team. After surgery, all patients received continuous respiratory surveillance in PACU (average duration exceeding 140 min). Respiratory depression events were scored using a modified list of the five standard published categories. Events were measured according to analysis of continuously recorded tracing of the compiled respiratory variables by observers kept blind from the study patient’s group. Results: Of the 80 patients evaluated (18 male), 56 had obstructive sleep apnea and were using CPAP at home (OSA); 24 did not. OSA patients received CPAP via an oronasal mask or a nasal pillow pressure support immediately after arriving in PACU, utilizing their at-home settings. We encountered 115 respiratory depression events across 48 patients. The most frequent respiratory event recorded was a transient desaturation (as low as 85%), which usually lasted 20–30 sec and resolved spontaneously in 3 to 5 min; most episodes followed small boluses of IV opioid analgesia administered during recovery, on demand. All episodes resolved spontaneously without any nursing or medical intervention. OSA patients had significantly more events than non-OSA patients (1.84 (1.78–1.9) mean events vs. 0.50 (0.43–0.57) for non-OSA, p = 0.0002). The level of PRODIGY score (low, intermediate, or high), instead, was not predictive of the number of events when we treated this variable as continuous (p = 0.39) or categorical (high vs. low, p = 0.65, and intermediate vs. low, p = 0.17). Conclusions: We attribute these novel results, showing a lack of respiratory events requiring intervention, to opioid-free anesthesia, early CPAP utilization, and head-up positioning on admission to PACU. Furthermore, all these patients had light postoperative narcotic requirements. Finally, an elevated PRODIGY score in our patients did not sufficiently predict respiratory events, but OSA status alone did. Key Points Summary: We investigated the incidence of Respiratory Events (RE) in Obstructive Sleep Apnea patients after surgery (56 patients) and compared them to similar patients without OSA (24 patients). All patients received identical robotic-assisted surgery and low- or no-opiate anesthesia. Patients were pre-screened with the standard published PRODIGY scores and were monitored after PACU arrival with continuous oximetry and capnography (Capnostream 35 and Profox analysis). OSA patients showed more RE than non-OSA (1.8 vs. 0.5, p = −0.0002). However, patients with elevated PRODIGY scores did not develop more frequent RE compared to patients with low scores. We attribute these novel results to opioid-sparing anesthesia/analgesia and immediate CPAP utilization on admission to PACU.

Review of Postoperative Respiratory Depression: From Recovery Room to General Care Unit

Contemporary evidence suggests that episodes of respiratory depression during anesthesia recovery are associated with subsequent respiratory complications in general care units.

Validation of the STOP-Bang questionnaire as a preoperative screening tool for obstructive sleep apnea: a systematic review and meta-analysis

BACKGROUND

Obstructive sleep apnea (OSA) is a common disorder that is highly associated with postoperative complications. The STOP-Bang questionnaire is a simple screening tool for OSA. The objective of this systematic review and meta-analysis is to evaluate the validity of the STOP-Bang questionnaire for screening OSA in the surgical population cohort.

METHODS

A systematic search of the following databases was performed from 2008 to May 2021: MEDLINE, Medline-in-process, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, PsycINFO, Journals @ Ovid, Web of Science, Scopus, and CINAHL. Continued literature surveillance was performed through October 2021.

RESULTS

The systematic search identified 4641 articles, from which 10 studies with 3247 surgical participants were included in the final analysis. The mean age was 57.3 ± 15.2 years, and the mean BMI was 32.5 ± 10.1 kg/m² with 47.4% male. The prevalence of all, moderate-to-severe, and severe OSA were 65.2, 37.7, and 17.0%, respectively. The pooled sensitivity of the STOP-Bang questionnaire for all, moderate-to-severe, and severe OSA was 85, 88, and 90%, and the pooled specificities were 47, 29, and 27%, respectively. The area under the curve for all, moderate-to-severe, and severe OSA was 0.84, 0.67, and 0.63.

CONCLUSIONS

In the preoperative setting, the STOP-Bang questionnaire is a valid screening tool to detect OSA in patients undergoing surgery, with a high sensitivity and a high discriminative power to reasonably exclude severe OSA with a negative predictive value of 93.2%.

TRIAL REGISTRATION

PROSPERO registration  CRD42021260451 .

Characteristics of Patients with Unrecognized Sleep Apnea Requiring Postoperative Oxygen Therapy

Surgical patients with obstructive sleep apnea (OSA) have increased risk of perioperative complications. The primary objective is to determine the characteristics of surgical patients with unrecognized OSA requiring oxygen therapy for postoperative hypoxemia. The secondary objective is to investigate the characteristics of patients who were responsive to oxygen therapy. This was a post-hoc multicenter study involving patients with cardiovascular risk factors undergoing major non-cardiac surgery. Patients ≥45 years old underwent Type 3 sleep apnea testing and nocturnal oximetry preoperatively. Responders to oxygen therapy were defined as individuals with ≥50% reduction in oxygen desaturation index (ODI) on postoperative night 1 versus preoperative ODI. In total, 624 out of 823 patients with unrecognized OSA required oxygen therapy. These were mostly males, had larger neck circumferences, higher Revised Cardiac Risk Indices, higher STOP-Bang scores, and higher ASA physical status, undergoing intraperitoneal or vascular surgery. Multivariable regression analysis showed that the preoperative longer cumulative time SpO2 < 90% or CT90% (adjusted p = 0.03), and lower average overnight SpO2 (adjusted p < 0.001), were independently associated with patients requiring oxygen therapy. Seventy percent of patients were responders to oxygen therapy with ≥50% ODI reduction. Preoperative ODI (19.0 ± 12.9 vs. 14.1 ± 11.4 events/h, p < 0.001), CT90% (42.3 ± 66.2 vs. 31.1 ± 57.0 min, p = 0.038), and CT80% (7.1 ± 22.6 vs. 3.6 ± 8.7 min, p = 0.007) were significantly higher in the responder than the non-responder. Patients with unrecognized OSA requiring postoperative oxygen therapy were males with larger neck circumferences and higher STOP-Bang scores. Those responding to oxygen therapy were likely to have severe OSA and worse preoperative nocturnal hypoxemia. Preoperative overnight oximetry parameters may help in stratifying patients.

The prevention of delirium in elderly surgical patients with obstructive sleep apnea (PODESA): a randomized controlled trial

BACKGROUND

Obstructive sleep apnea (OSA) is associated with neurocognitive impairment - a known risk factor for postoperative delirium. However, it is unclear whether OSA increases the risk of postoperative delirium and whether treatment is protective. The objectives of this study were to identify OSA with a home sleep apnea test (HSAT) and to determine whether auto-titrating positive airway pressure (APAP) reduces postoperative delirium in older adults with newly diagnosed OSA undergoing elective hip or knee arthroplasty.

METHODS

We conducted a multi-centre, randomized controlled trial at three academic hospitals in Canada. Research ethics board approval was obtained from the participating sites and informed consent was obtained from participants. Inclusion criteria were patients who were [Formula: see text]0 years and scheduled for elective hip or knee replacement. Patients with a STOP-Bang score of ≥ 3 had a HSAT. Patients were defined as having OSA if the apnea-hypopnea index was ≥ 10/h. These patients were randomized 1:1 to either: 1) APAP for 72 h postoperatively or until discharge, or 2) routine care after surgery. The primary outcome was postoperative delirium, assessed twice daily with the Confusion Assessment Method for 72 h or until discharge or by chart review. The secondary outcome measures included length of stay, and perioperative complications occurring within 30 days after surgery.

RESULTS

Of 549 recruited patients, 474 completed a HSAT. A total of 234 patients with newly diagnosed OSA were randomized. The mean age was 68.2 (6.2) years and 58.6% were male. Analysis was performed on 220 patients. In total, 2.7% (6/220) patients developed delirium after surgery: 4.4% (5/114) patients in the routine care group, and 0.9% (1/106) patients in the treatment group (P = 0.21). The mean length of stay for the APAP vs. the routine care group was 2.9 (2.9) days vs. 3.5 (4.5) days (P = 0.24). On postoperative night 1, 53.5% of patients used APAP for 4 h/night or more, this decreased to 43.5% on night 2, and 24.6% on night 3. There was no difference in intraoperative and postoperative complications between the two groups.

CONCLUSIONS

We had an unexpectedly low rate of postoperative delirium thus we were unable to determine if postoperative delirium was reduced in older adults with newly diagnosed OSA receiving APAP vs. those who did not receive APAP after elective knee or hip arthroplasty.

TRIAL REGISTRATION

This trial was retrospectively registered in clinicaltrials.gov NCT02954224 on 03/11/2016.

Accuracy of Oxygen Saturation Measurements in Patients with Obesity Undergoing Bariatric Surgery

BACKGROUND

We aimed to determine the magnitude, direction, and influencing factors of the concordance between arterial oxygen saturation (SaO₂) and peripheral capillary oxygen saturation (SpO₂) in patients with obesity undergoing bariatric surgery, supporting the measurement of SaO₂ and SpO₂ in key populations.

METHODS

Patients with obesity undergoing bariatric surgery from 2017 to 2020 were included. Preoperative SpO₂ and SaO₂ were collected. Linear correlation and multiple linear regression analyses were performed to characterize the relationships between body mass index (BMI), age, and sex with pulse oximetry and arterial blood gas (ABG) parameters. Bland-Altman analysis was applied to determine the concordance between SpO₂ and SaO₂ and the limits of this concordance.

RESULTS

A total of 134 patients with obesity undergoing bariatric surgery were enrolled. SaO₂ was negatively associated with BMI (p < 0.0001) and age (p = 0.006), and SpO₂ was negatively associated with BMI (p = 0.021) but not with age. SpO₂ overestimated SaO₂ in 91% of patients with a bias of 2.05%. This bias increased by 203% in hypoxemic patients compared with nonhypoxemic patients (p < 0.0001). The bias was 1.3-fold higher (p = 0.023) in patients with a high obesity surgery mortality risk score (OS-MRS) than in those with low or intermediate scores.

CONCLUSION

Compared with SpO₂, preoperative SaO₂ can more accurately reflect the real oxygen saturation in patients with obesity undergoing bariatric surgery, especially for those with BMI ≥ 40 kg/m², age ≥ 40 years, and high OS-MRS. ABG analysis can provide a more reliable basis for accurate and timely monitoring, ensuring the perioperative safety of susceptible patients.

Perioperative outcomes of patients with restless legs syndrome: a single-center retrospective review

STUDY OBJECTIVES

There are multiple stressors in the perioperative period for patients with restless legs syndrome (RLS) that may be implicated in the worsening of symptoms. Our primary objective was to compare the perioperative course of patients with RLS to patients without the diagnosis.

METHODS

This was a single-center, matched-cohort, retrospective chart review of patients with RLS undergoing inpatient procedures from 2015-2019 matched 1:1 with patients without the diagnosis.

RESULTS

Patients with RLS had a higher comorbidity burden; specifically, pulmonary, renal, diabetes mellitus, and congestive heart failure. The perioperative course was notable for higher maximum pain scores for patients with RLS in the postanesthesia care unit (odds ratio, 1.29; 95% confidence interval, 1.19-1.40; P < .001). Postoperative patients with RLS also had higher maximum pain scores on postoperative days 0, 1, and 2. The odds of rapid-response calls were higher in patients with RLS (odds ratio, 1.43; 95% confidence interval, 1.18-1.73; P < .001). There were no other significant differences in postoperative complications. The odds of using RLS-triggering medications were lower in the RLS group (odds ratio, 0.85; 95% confidence interval, 0.78-0.92; P < .001).

CONCLUSIONS

Our single-center retrospective review found that patients with RLS had higher pain scores in the postanesthesia care unit and on the first few postoperative days. Rapid-response team calls were more common in patients with RLS. RLS-triggering medications were significantly less likely to be used in patients with RLS. There were no significant differences in other postoperative events.

CITATION

Gali B, Silber MH, Hanson AC, Portner E, Gay P. Perioperative outcomes of patients with restless legs syndrome: a single-center retrospective review. J Clin Sleep Med. 2022:18(7):1841-1846.

Perioperative considerations for adult patients with obstructive sleep apnea

PURPOSE OF REVIEW

Obstructive sleep apnea (OSA) is a common, but often undiagnosed, sleep breathing disorder affecting approximately a third of adult surgical patients. OSA patients have increased sensitivity to anesthetic agents, sedatives, and opioid analgesics.

RECENT FINDINGS

Newer technologies (e.g., bedside capnography) have demonstrated that OSA patients have repetitive apneic spells, beginning in the immediate postoperative period and peaking in frequency during the first postoperative night. Compared to patients without OSA, OSA patients have double the risk for postoperative pulmonary as well as other complications, and OSA has been linked to critical postoperative respiratory events leading to anoxic brain injury or death. Patients with OSA who have respiratory depression during anesthesia recovery have been found to be high-risk for subsequent pulmonary complications. Gabapentinoids have been linked to respiratory depression in these patients.

SUMMARY

Surgical patients should be screened for OSA and patients with OSA should continue using positive airway pressure devices postoperatively. Use of shorter acting and less sedating agents and opioid sparing anesthetic techniques should be encouraged. In particular, OSA patients exhibiting signs of respiratory depression in postanesthesia recovery unit should receive enhancer respiratory monitoring following discharge to wards.

Clinical implications of opioid-induced ventilatory impairment

Opioid-induced ventilatory impairment is the primary mechanism of harm from opioid use. Opioids suppress the activity of the central respiratory centres and are sedating, leading to impairment of alveolar ventilation.Respiratory physiological changes induced with acute opioid use include depression of the hypercapnic ventilatory response and hypoxic ventilatory response. In chronic opioid use a compensatory increase in hypoxic ventilatory response maintains ventilation and contributes to the onset of sleep-disordered breathing patterns of central sleep apnoea and ataxic breathing. Supplemental oxygen use in those at risk of opioid-induced ventilatory impairment requires careful consideration by the clinician to prevent failure to detect hypoventilation, if oximetry is being relied on, and the overriding of hypoxic ventilatory drive. Obstructive sleep apnoea and opioid-induced ventilatory impairment are frequently associated, with this interrelationship being complex and often unpredictable. Monitoring the patient for opioid-induced ventilatory impairment poses challenges in the areas of reliability, avoidance of alarm fatigue, cost, and personnel demands. Many situations remain in which patients cannot be provided effective analgesia without opioids, and for these the clinician requires a comprehensive knowledge of opioid-induced ventilatory impairment.

Opioids in acute pain: Towards getting the right balance

Misuse of prescription opioids forced an inevitable response from authorities to intervene with consequences felt by all.In the Australian community one person will die for approximately every 3600 adults prescribed opioids, while in the hospital setting a postoperative patient managed primarily with opioids, as opposed to epidural analgesia, has an additional risk of death as high as between one in 56 to 477.Opioids maintain a valid role in acute pain management when use is reasoned and with full awareness of the harms and how they are to be avoided, such as in those at risk of ongoing use, the opioid naïve, and when opioid-induced ventilatory impairment may occur.Clinicians managing acute pain can focus on assessing pain versus nociception, strategically apply antinociceptive medications and neural blockade when indicated, assess pain with an emphasis on the degree of bothersomeness and functional impairment and, finally, optimise the use of framing and placebo-enhancing communication to minimise reliance on medications.

Current Issues in the Use of Opioids for the Management of Postoperative Pain: A Review

Importance

Uncontrolled and indiscriminate prescribing of opioids has led to an opioid crisis that started in North America and spread throughout high-income countries. The aim of this narrative review was to explore some of the current issues surrounding the use of opioids in the perioperative period, focusing on drivers that led to escalation of use, patient harms, the move away from using self-reported pain scores alone to assess adequacy of analgesia, concerns about the routine use of controlled-release opioids for the management of acute pain, opioid-free anesthesia and analgesia, and prescription of opioids on discharge from hospital.

Observations

The origins of the opioid crisis are multifactorial and may include good intentions to keep patients pain free in the postoperative period. Assessment of patient function may be better than unidimensional numerical pain scores to help guide postoperative analgesia. Immediate-release opioids can be titrated more easily to match analgesic requirements. There is currently no good evidence to show that opioid-free anesthesia and analgesia affects opioid prescribing practices or the risk of persistent postoperative opioid use. Attention should be paid to discharge opioid prescribing as repeat and refill prescriptions are risk-factors for persistent postoperative opioid use. Opioid stewardship is paramount, and many governments are passing legislation, while statutory bodies and professional societies are providing advice and guidance to help mitigate the harm caused by opioids.

Conclusions and Relevance

Opioids remain a crucial part of many patients' journey from surgery to full recovery. The last few decades have shown that unfettered opioid use puts patients and societies at risk, so caution is needed to mitigate those dangers. Opioid stewardship provides a multilayered structure to allow continued safe use of opioids as part of broad pain management strategies for those patients who benefit from them most.

Guidelines for Perioperative Care in Bariatric Surgery: Enhanced Recovery After Surgery (ERAS) Society Recommendations: A 2021 Update

Background

This is the second updated Enhanced Recovery After Surgery (ERAS®) Society guideline, presenting a consensus for optimal perioperative care in bariatric surgery and providing recommendations for each ERAS item within the ERAS® protocol.

Methods

A principal literature search was performed utilizing the Pubmed, EMBASE, Cochrane databases and ClinicalTrials.gov through December 2020, with particular attention paid to meta-analyses, randomized controlled trials and large prospective cohort studies. Selected studies were examined, reviewed and graded according to the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system. After critical appraisal of these studies, the group of authors reached consensus regarding recommendations.

Results

The quality of evidence for many ERAS interventions remains relatively low in a bariatric setting and evidence-based practices may need to be extrapolated from other surgeries.

Conclusion

A comprehensive, updated evidence-based consensus was reached and is presented in this review by the ERAS® Society.

Patients with sleep-disordered breathing for bariatric surgery

The prevalence of patients with obesity continues to rise worldwide and has reached epidemic proportions. There is a strong correlation between obesity and sleep-disordered breathing (SDB), and, in particular, obstructive sleep apnea (OSA). OSA is often undiagnosed in the surgical population. Bariatric surgery has been recognized as an effective treatment option for both obesity and OSA. Laparoscopic bariatric procedures, particularly laparoscopic sleeve gastrectomy (LSG), have become the most frequently performed procedures. OSA has been identified as an independent risk factor for perioperative complications and failure to recognize and prepare for patients with OSA is a major cause of postoperative adverse events, suggesting that all patients undergoing bariatric surgery should be screened preoperatively for OSA. These patients should be treated with an opioid-sparing analgesic plan and continuous positive airway pressure (CPAP) perioperatively to minimize respiratory complications. With the number of bariatric surgical patients with SDB likely to continue rising, it is critical to understand the best practices to manage this patient population.

Impact of a continuous enhanced cardio-respiratory monitoring pathway on cardio-respiratory complications after bariatric surgery: A retrospective cohort study

STUDY OBJECTIVE

To determine the impact of an enhanced monitoring pathway consisting of continuous postoperative cardio-respiratory monitoring on adverse outcomes after bariatric.

DESIGN

Single-center, retrospective cohort study.

PATIENTS

Adult patients who underwent bariatric surgeries between 2009 and 2016.

INTERVENTIONS

We evaluated the use of an enhanced monitoring pathway consisting of a distant, continuous, non-invasive respiratory monitoring system on postoperative cardio-respiratory complications in patients undergoing bariatric surgery. Treating physicians had the option to assign patients to enhanced monitoring (intervention group) in the postoperative period for suspected or diagnosed OSA or other clinical concerns. The control group had intermittent vital sign checks as per institutional standards.

MEASUREMENTS

The primary outcome was a composite of cardio-respiratory complications (rapid response team activation, intensive care admission, respiratory complications), major adverse cardiac events, and all-cause mortality. The secondary outcome was length of stay (LOS).

MAIN RESULTS

Of 1450 patients, 752 patients received enhanced monitoring (intervention) and 698 patients received standard monitoring (control). Univariate analysis showed that, compared to control, enhanced monitoring was associated with lower odds of composite cardio-respiratory complications (OR: 0.41, 95%CI: 0.32-0.53, p < 0.001) and lower odds of prolonged LOS > 2 days (OR: 0.37, 95% CI: 0.28-0.49, p < 0.001. After adjusting for potential confounders, enhanced monitoring remained associated with a reduction in composite cardio-respiratory complications (OR: 0.64, 95% CI: 0.46-0.88, p = 0.005).

CONCLUSIONS

Our study demonstrates that postoperative enhanced monitoring pathway was associated with a lower incidence of cardio-respiratory composite events, compared to a standard of care, in patients undergoing bariatric surgery. As our results show association rather than causation, future prospective randomized trials are needed to confirm the benefit of enhanced monitoring. Findings of our study add to the existing literature involved in clinical management pathways to reduce the incidence of adverse postoperative outcomes in high-risk patients undergoing inpatient surgeries.

Relevance of Sleep Disturbances to Orthopaedic Surgery: A Current Concepts Narrative and Practical Review

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Sleep disturbances can increase the risk of falls and motor vehicle accidents and may reduce bone density.

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Poor sleep can lead to worse outcomes after fracture, such as chronic pain and delayed recovery.

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Orthopaedic surgeons can play an important role in the screening of sleep disorders among their patients.

Prefrontal Cortex Metabolome Is Modified by Opioids, Anesthesia, and Sleep

Obtundation of wakefulness caused by opioids and loss of wakefulness caused by anesthetics and sleep significantly alter concentrations of molecules comprising the prefrontal cortex (PFC) metabolome. Quantifying state-selective changes in the PFC metabolome is essential for advancing functional metabolomics. Diverse functions of the PFC suggest the PFC metabolome as a potential therapeutic entry point for countermeasures to state-selective autonomic dysfunction.

Advanced endoscopic gastrointestinal techniques for the bariatric patient: implications for the anesthesia provider

PURPOSE OF REVIEW

The incidence of obesity and the use of endoscopy have risen concurrently throughout the 21st century. Bariatric patients may present to the endoscopy suite for primary treatments as well as preoperatively and postoperatively from bariatric surgery. However, over the past 10 years, endoscopic bariatric and metabolic therapies (EBMTs) have emerged as viable alternatives to more invasive surgical approaches for weight loss.

RECENT FINDINGS

The United States Food and Drug Administration (FDA) has approved several different gastric EBMTs including aspiration therapy, intragastric balloons, and endoscopic suturing. Other small intestine EBMTs including duodenal mucosal resurfacing, endoluminal magnetic partial jejunal diversion, and Duodenal-Jejunal Bypass Liner are not yet FDA approved, but are actively being investigated.

SUMMARY

Obesity causes anatomic and physiologic changes to every aspect of the human body. All EBMTs have specific nuances with important implications for the anesthesiologist. By considering both patient and procedural factors, the anesthesiologist will be able to perform a safe and effective anesthetic.

Differential Perioperative Outcomes in Patients With Obstructive Sleep Apnea, Obesity, or a Combination of Both Undergoing Open Colectomy: A Population-Based Observational Study

BACKGROUND

An increasing body of evidence demonstrates an association between obstructive sleep apnea (OSA) and adverse perioperative outcomes. However, large-scale data on open colectomies are lacking. Moreover, the interaction of obesity with OSA is unknown. This study examines the impact of OSA, obesity, or a combination of both, on perioperative complications in patients undergoing open colectomy. We hypothesized that while both obesity and OSA individually increase the likelihood for perioperative complications, the overlap of the 2 conditions is associated with the highest risk.

METHODS

Patients undergoing open colectomies were identified using the national Premier Healthcare claims-based Database (2006-2016; n = 340,047). Multilevel multivariable models and relative excess risk due to interaction (RERI) analysis quantified the impact of OSA, obesity, or both on length and cost of hospitalization, respiratory and cardiac complications, intensive care unit (ICU) admission, mechanical ventilation, and inhospital mortality.

RESULTS

Nine thousand twenty-eight (2.7%) patients had both OSA and obesity diagnoses; 10,137 (3.0%) had OSA without obesity; and 33,692 (9.9%) had obesity without OSA. Although there were overlapping confidence intervals in the binary outcomes, the risk increase was found highest for OSA with obesity, intermediate for obesity without OSA, and lowest for OSA without obesity. The strongest effects were seen for respiratory complications: odds ratio (OR), 2.41 (2.28-2.56), OR, 1.40 (1.31-1.49), and OR, 1.50 (1.45-1.56), for OSA with obesity, OSA without obesity, and obesity without OSA, respectively (all P < .0001). RERI analysis revealed a supraadditive effect of 0.51 (95% confidence interval [CI], 0.34-0.68) for respiratory complications, 0.11 (-0.04 to 0.26) for cardiac complications, 0.30 (0.14-0.45) for ICU utilization, 0.34 (0.21-0.47) for mechanical ventilation utilization, and 0.26 (0.15-0.37) for mortality in patients with both OSA and obesity, compared to the sum of the conditions' individual risks. Inhospital mortality was significantly higher in patients with both OSA and obesity (OR [CI], 1.21 [1.07-1.38]) but not in the other groups.

CONCLUSIONS

Both OSA and obesity are individually associated with adverse perioperative outcomes, with a supraadditive effect if both OSA and obesity are present. Interventions, screening, and perioperative precautionary measures should be tailored to the respective risk profile. Moreover, both conditions appear to be underreported compared to the general population, highlighting the need for stringent perioperative screening, documentation, and reporting.

Identification of Sleep Medicine and Anesthesia Core Topics for Anesthesia Residency: A Modified Delphi Technique Survey

BACKGROUND

Sleep disorders affect up to 25% of the general population and are associated with increased risk of adverse perioperative events. The key sleep medicine topics that are most important for the practice of anesthesiology have not been well-defined. The objective of this study was to determine the high-priority sleep medicine topics that should be included in the education of anesthesia residents based on the insight of experts in the fields of anesthesia and sleep medicine.

METHODS

We conducted a prospective cross-sectional survey of experts in the fields of sleep medicine and anesthesia based on the Delphi technique to establish consensus on the sleep medicine topics that should be incorporated into anesthesia residency curricula. Consensus for inclusion of a topic was defined as >80% of all experts selecting "agree" or "strongly agree" on a 5-point Likert scale. Responses to the survey questions were analyzed with descriptive statistical methods and presented as percentages or weighted mean values with standard deviations (SD) for Likert scale data.

RESULTS

The topics that were found to have 100% agreement among experts were the influence of opioids and anesthetics on control of breathing and upper airway obstruction; potential interactions of wake-promoting/hypnotic medications with anesthetic agents; effects of sleep and anesthesia on upper airway patency; and anesthetic management of sleep apnea. Less than 80% agreement was found for topics on the anesthetic implications of other sleep disorders and future pathways in sleep medicine and anesthesia.

CONCLUSIONS

We identify key topics of sleep medicine that can be included in the future design of anesthesia residency training curricula.

Perioperative Management of the Patient With Obstructive Sleep Apnea: A Narrative Review

The prevalence of obstructive sleep apnea (OSA) has reached 1 billion people worldwide, implying significant risk for the perioperative setting as patients are vulnerable to cardiopulmonary complications, critical care requirement, and unexpected death. This review summarizes main aspects and considerations for the perioperative management of OSA, a condition of public health concern. Critical determinants of perioperative risk include OSA-related changes in upper airway anatomy with augmented collapsibility, diminished capability of upper airway dilator muscles to respond to airway obstruction, disparities in hypoxemia and hypercarbia arousal thresholds, and instability of ventilatory control. Preoperative OSA screening to identify patients at increased risk has therefore been implemented in many institutions. Experts recommend that in the absence of severe symptoms or additional compounding health risks, patients may nevertheless proceed to surgery, while heightened awareness and the adjustment of postoperative care is required. Perioperative caregivers should anticipate difficult airway management in OSA and be prepared for airway complications. Anesthetic and sedative drug agents worsen upper airway collapsibility and depress central respiratory activity, while the risk for postoperative respiratory compromise is further increased with the utilization of neuromuscular blockade. Consistently, opioid analgesia has proven to be complex in OSA, as patients are particularly prone to opioid-induced respiratory depression. Moreover, basic features of OSA, including intermittent hypoxemia and repetitive sleep fragmentation, gradually precipitate a higher sensitivity to opioid analgesic potency along with an increased perception of pain. Hence, regional anesthesia by blockade of neural pathways directly at the site of surgical trauma as well as multimodal analgesia by facilitating additive and synergistic analgesic effects are both strongly supported in the literature as interventions that may reduce perioperative complication risk. Health care institutions are increasingly allocating resources, including those of postoperative enhanced monitoring, in an effort to increase patient safety. The implementation of evidence-based perioperative management strategies is however burdened by the rising prevalence of OSA, the large heterogeneity in disease severity, and the lack of evidence on the efficacy of costly perioperative measures. Screening and monitoring algorithms, as well as reliable risk predictors, are urgently needed to identify OSA patients that are truly in need of extended postoperative surveillance and care. The perioperative community is therefore challenged to develop feasible pathways and measures that can confer increased patient safety and prevent complications in patients with OSA.

Pharmacologically Induced Ventilatory Depression in the Postoperative Patient: A Sleep-Wake State-Dependent Perspective

Pharmacologically induced ventilatory depression (PIVD) is a common postoperative complication with a spectrum of severity ranging from mild hypoventilation to severe ventilatory depression, potentially leading to anoxic brain injury and death. Recent studies, using continuous monitoring technologies, have revealed alarming rates of previously undetected severe episodes of postoperative ventilatory depression, rendering the recognition of such episodes by the standard intermittent assessment practice, quite problematic. This imprecise description of the epidemiologic landscape of PIVD has thus stymied efforts to understand better its pathophysiology and quantify relevant risk factors for this postoperative complication. The residual effects of various perianesthetic agents on ventilatory control, as well as the multiple interactions of these drugs with patient-related factors and phenotypes, make postoperative recovery of ventilation after surgery and anesthesia a highly complex physiological event. The sleep-wake, state-dependent variation in the control of ventilation seems to play a central role in the mechanisms potentially enhancing the risk for PIVD. Herein, we discuss emerging evidence regarding the epidemiology, risk factors, and potential mechanisms of PIVD.

Predictive performance of oximetry in detecting sleep apnea in surgical patients with cardiovascular risk factors

INTRODUCTION

In adults with cardiovascular risk factors undergoing major noncardiac surgery, unrecognized obstructive sleep apnea (OSA) was associated with postoperative cardiovascular complications. There is a need for an easy and accessible home device in predicting sleep apnea. The objective of the study is to determine the predictive performance of the overnight pulse oximetry in predicting OSA in at-risk surgical patients.

METHODS

This was a planned post-hoc analysis of multicenter prospective cohort study involving 1,218 at-risk surgical patients without prior diagnosis of sleep apnea. All patients underwent home sleep apnea testing (ApneaLink Plus, ResMed) simultaneously with pulse oximetry (PULSOX-300i, Konica Minolta Sensing, Inc). The predictive performance of the 4% oxygen desaturation index (ODI) versus apnea-hypopnea index (AHI) were determined.

RESULTS

Of 1,218 patients, the mean age was 67.2 ± 9.2 years and body mass index (BMI) was 27.0 ± 5.3 kg/m2. The optimal cut-off for predicting moderate-to-severe and severe OSA was ODI ≥15 events/hour. For predicting moderate-to-severe OSA (AHI ≥15), the sensitivity and specificity of ODI ≥ 15 events per hour were 88.4% (95% confidence interval [CI], 85.7-90.6) and 95.4% (95% CI, 94.2-96.4). For severe OSA (AHI ≥30), the sensitivity and specificity were 97.2% (95% CI, 92.7-99.1) and 78.8% (95% CI, 78.2-79.0). The area under the curve (AUC) for moderate-to-severe and severe OSA was 0.983 (95% CI, 0.977-0.988) and 0.979 (95% CI, 0.97-0.909) respectively.

DISCUSSION

ODI from oximetry is sensitive and specific in predicting moderate-to-severe or severe OSA in at-risk surgical population. It provides an easy, accurate, and accessible tool for at-risk surgical patients with suspected OSA.

A capnography and transcutaneous CO2 profile of bariatric patients during early postoperative period after opioid-sparing anesthesia

BACKGROUND

Noninvasive monitoring of partial pressure of carbon dioxide can be accomplished indirectly with capnography (P_ETCO₂) or with transcutaneous carbon dioxide monitoring (P_TCCO₂). The use of capnography has been shown to offer an advantage over pulse oximetry alone in the early detection of adverse respiratory events when supplemental oxygen is administered. Furthermore, capnography allows for the monitoring of various respiratory measures, including end-tidal carbon dioxide, respiratory rate, tidal volume, and changes in breathing patterns. Transcutaneous CO₂ also closely approximates arterial CO₂ values, but is not as easy to monitor for prolonged periods. The purpose of this study was to examine the usefulness of capnography and of transcutaneous carbon dioxide monitoring in patients recovering from obesity surgery at high risk of developing postoperative obstructive sleep apnea.

METHODS

In a prospective observational study, 64 bariatric surgery patients at risk of developing obstructive sleep apnea were monitored in the postanesthesia care unit (PACU) with either capnography alone (31 patients) or capnography plus transcutaneous carbon dioxide monitoring (33 additional patients) every 3-5 minutes for the duration of their recovery. Primary endpoints included end-tidal and transcutaneous carbon dioxide, peripheral oxygen saturation, respiratory rate, pain scores, and incidence of adverse respiratory events.

RESULTS

Although no adverse pulmonary events were observed, capnography detected several patients who experienced short periods of respiratory apnea while maintaining pulse oximetry readings within normal limits. Transcutaneous values were slow to change and averaged 4.5 ± 5.5 mm Hg (P < .05) higher than corresponding end-tidal measurements.

CONCLUSIONS

These results indicate the capabilities of both these noninvasive techniques for postoperative monitoring. Capnography acutely monitors changes in respiration, whereas transcutaneous monitoring more accurately reflects arterial CO₂ levels.