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.

International Consensus Statement on Obstructive Sleep Apnea.

BACKGROUND: Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA). METHODS: Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus. RESULTS: The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated. CONCLUSION: This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

Perioperative trends in neck and leg fluid volume in surgical patients: a prospective observational proof-of-concept study.

PURPOSE: The severity of obstructive sleep apnea (OSA) may increase postoperatively. The changes in segmental fluid volume, especially neck fluid volume, may be related to increasing airway collapsibility and thus worsening of OSA in the postoperative period. Our objective was to evaluate the feasibility of performing bioelectrical impedance analysis (BIA) and to describe the trend and predictors of changes in segmental fluid volumes in patients receiving general anesthesia for noncardiac surgery. METHODS: We conducted a prospective observational proof-of-concept cohort study of adult patients undergoing elective inpatient noncardiac surgery. Patients underwent a portable sleep study before surgery, and segmental fluid volumes (neck fluid volume [NFV], NFV phase angle, and leg fluid volume [LFV]) were measured using BIA at set time points: preoperative period (preop), in the postanesthesia care unit (PACU), the night following surgery at 10 pm (N 0), and the following day at 10 am (POD 1). Linear regression models were constructed to evaluate for significant predictors of overall segmental fluid changes. The variables included in the models were sex, preoperative apnea-hypopnea index (AHI), fluid balance, body mass index (BMI), cumulative opioids, and the timepoint of measurement. RESULTS: Thirty-five adult patients (20/35 females, 57%) were included. For the feasibility outcome, measure of recruitment was 50/66 (76%) and two measures of protocol adherence were fluid measurements (34/39, 87%) and preoperative sleep study (35/39, 90%). There was a significant increase in NFV from preop to N 0 and in LFV from preop to PACU. Neck fluid volume also increased from PACU to N 0 and PACU to POD 1, while LFV decreased during the same intervals. The overall changes in NFV were associated with the preop AHI, BMI, and opioids after adjusting for body position and pneumoperitoneum. CONCLUSIONS: This proof-of-concept study showed the feasibility and variability of segmental fluid volumes in the perioperative period using BIA. We found an increase in NFV and LFV in the immediate postoperative period in both males and females, followed by the continued rise in NFV and a simultaneous decrease in LFV, which suggest the occurrence of rostral fluid shift. Preoperative AHI, BMI, and opioids predicted the NFV changes. STUDY REGISTRATION: ClinicalTrials.gov; NCT02666781, registered 25 January 2016; NCT03850041, registered 20 February 2019.

RéSUMé: OBJECTIF: La gravité de l'apnée obstructive du sommeil (AOS) peut augmenter en période postopératoire. Les changements dans le volume segmentaire de fluides, en particulier le volume liquidien du cou, peuvent être liés à l'augmentation de la collapsibilité des voies aériennes et donc à l'aggravation d'une AOS en période postopératoire. Notre objectif était d'évaluer la faisabilité de réaliser une analyse d'impédance bioélectrique (AIB) et de décrire la tendance et les prédicteurs des changements dans les volumes de fluides segmentaires chez des patients recevant une anesthésie générale pour une chirurgie non cardiaque. MéTHODE: Nous avons réalisé une étude de cohorte observationnelle prospective de démonstration de faisabilité chez des patients adultes bénéficiant d'une chirurgie non cardiaque non urgente en milieu hospitalier. Les patients ont subi une étude du sommeil grâce à un appareil portable avant la chirurgie, et les volumes de fluides segmentaires (volume de fluides du cou, angle de phase VLC et volume de fluides des jambes) ont été mesurés à l'aide d'une AIB à des moments définis : période préopératoire (préop), en salle de réveil, la nuit suivant la chirurgie à 22 h (N 0) et le lendemain à 10 h (JPO 1). Des modèles de régression linéaire ont été construits pour évaluer les prédicteurs significatifs de changements globaux des fluides segmentaires. Les variables incluses dans les modèles étaient le sexe, l'indice d'apnée-hypopnée préopératoire (IAH), l'équilibre hydrique, l'indice de masse corporelle (IMC), les opioïdes cumulés et le point de mesure temporel. RéSULTATS: Trente-cinq patients adultes (20/35 femmes, 57 %) ont été inclus. En ce qui concerne le critère de faisabilité, la mesure du recrutement était de 50/66 (76 %) et deux mesures de l'observance du protocole étaient les mesures liquidiennes (34/39, 87 %) et une étude préopératoire du sommeil (35/39, 90 %). Il y a eu une augmentation significative du volume de fluides du cou entre la période préopératoire et N 0 et du volume de fluides des jambes de la période préopératoire à la salle de réveil. Le volume de fluides du cou a également augmenté de la salle de réveil à N 0 et de la salle de réveil au JPO 1, tandis que le volume de fluides des jambes a diminué au cours des mêmes intervalles. Les changements globaux de volume de fluides du cou ont été associés à l'IAH préopératoire, à l'IMC et aux opioïdes après ajustement pour tenir compte de la position du corps et du pneumopéritoine. CONCLUSION: Cette étude de preuve de concept a démontré la faisabilité de l'évaluation et la variabilité des volumes de fluide segmentaire dans la période périopératoire en utilisant l'IAB. Nous avons constaté une augmentation du volume liquidien du cou et des jambes en période postopératoire immédiate chez les hommes et les femmes, suivie d'une augmentation continue du volume liquidien du cou et d'une diminution simultanée du volume liquidien des jambes, ce qui laisserait penser à la survenue d'un déplacement du liquide rostral. L'indice d'apnée-hypopnée préopératoire, l'IMC et les opioïdes étaient des prédicteurs de changements du volume liquidien du cou. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov; NCT02666781, enregistré le 25 janvier 2016; NCT03850041, enregistré le 20 février 2019.

Perioperative adherence to continuous positive airway pressure and its effect on postoperative nocturnal hypoxemia in obstructive sleep apnea patients: a prospective cohort study.

BACKGROUND: Although continuous positive airway pressure (CPAP) is the first line treatment for obstructive sleep apnea (OSA) patients, the perioperative adherence rate is unclear. The objective of this study was to determine the perioperative adherence rate of patients with OSA with a CPAP prescription and the effect of adherence on nocturnal oxygen saturation. METHODS: This prospective cohort study included adult surgical patients with a diagnosis of OSA with CPAP prescription undergoing elective non-cardiac surgery. Patients were divided into CPAP adherent and non-adherent groups based on duration of usage (≥ 4 h/night). Overnight oximetry was performed preoperatively and on postoperative night 1 and 2 (N1, N2). The primary outcome was adherence rate and the secondary outcome was nocturnal oxygen saturation. RESULTS: One hundred and thirty-two patients completed the study. CPAP adherence was 61% preoperatively, 58% on postoperative N1, and 59% on N2. Forty-nine percent were consistently CPAP adherent pre- and postoperatively. Using a linear fixed effects regression, oxygen desaturation index (ODI) was significantly improved by CPAP adherence (p = 0.0011). The interaction term CPAP x N1 was significant (p = 0.0015), suggesting that the effect of CPAP adherence varied on N1 vs preoperatively. There was no benefit of CPAP adherence on postoperative mean SpO2, minimum SpO2, and percentage of sleep duration with SpO2 < 90%. Use of supplemental oxygen therapy was much lower in the CPAP adherent group vs non-adherent group (9.8% vs 46.5%, p <  0.001). CONCLUSIONS: Among patients with a preoperative CPAP prescription, approximately 50% were consistently adherent. CPAP adherence was associated with improved preoperative ODI and the benefit was maintained on N1. These modest effects may be underestimated by a higher severity of OSA in the CPAP adherent group and a higher rate of oxygen supplementation in the non-adherent group. TRIAL REGISTRATION: ClinicalTrials.Gov registry ( NCT02796846 ).

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 Insomnia, Restless Legs, Narcolepsy, and Parasomnias.

Obstructive sleep apnea (OSA) has been shown to increase risk of adverse perioperative events. More recently, investigators have begun to examine other common sleep disorders to assess how they may be impacted by the perioperative environment, as well as influence postoperative outcomes. There are a number of mechanisms by which such common sleep disorders (eg, insomnia, restless legs syndrome, narcolepsy, and parasomnias) may have consequences in the perioperative setting, both related to the underlying pathophysiology of the diseases as well as their treatments. This review will highlight the current state of the literature and offer recommendations for management of these conditions during the perioperative journey.

Integrating Sleep Knowledge Into the Anesthesiology Curriculum.

There is common ground between the specialties of anesthesiology and sleep medicine. Traditional sleep medicine curriculum for anesthesiology trainees has revolved around the discussion of obstructive sleep apnea (OSA) and its perioperative management. However, it is time to include a broader scope of sleep medicine-related topics that overlap these specialties into the core anesthesia residency curriculum. Five main core competency domains are proposed, including SLeep physiology; Evaluation of sleep health; Evaluation for sleep disorders and clinical implications; Professional and academic roles; and WELLness (SLEEP WELL). The range of topics include not only the basics of the physiology of sleep and sleep-disordered breathing (eg, OSA and central sleep apnea) but also insomnia, sleep-related movement disorders (eg, restless legs syndrome), and disorders of daytime hypersomnolence (eg, narcolepsy) in the perioperative and chronic pain settings. Awareness of these topics is relevant to the scope of knowledge of anesthesiologists as perioperative physicians as well as to optimal sleep health and physician wellness and increase consideration among current anesthesiology trainees for the value of dual credentialing in both these specialties.

[The impact of unilateral diaphragmatic paralysis on sleep-disordered breathing: a scoping review]. / L'impact de la paralysie diaphragmatique unilatérale sur les troubles respiratoires du sommeil : une revue exploratoire.

BACKGROUND: Unilateral diaphragm paralysis (UDP) may potentially worsen sleep-disordered breathing (SDB). Unilateral diaphragm paralysis has been associated with proximal brachial plexus blockade, such as interscalene and supraclavicular block. The impact of UDP in patients with SDB is not known in this context. The objectives of this scoping review were to explore the associations between UDP and worsening SDB severity, oxygenation, and pulmonary function. METHODS: A systematic search was developed, peer-reviewed, and applied to Embase, Medline, CINAHL, and Cochrane databases to include studies involving adult patients (≥ 18 yr) with SDB, where the effects of UDP on SDB severity, oxygenation, and pulmonary function were examined. RESULTS: Six studies (n = 100 patients) with UDP and SDB were included. The sample population was derived exclusively from respirology-sleep clinics, and none were surgical patients. Compared with control (no UDP), UDP was associated with an increased respiratory disturbance index, most pronounced during rapid eye movement (REM) sleep and supine sleep. Supine and REM sleep were associated with obstructive and mixed (both obstructive and central) events, respectively. Compared with control, UDP was associated with a lower mean and minimum oxygen saturation and arterial oxygen tension during all sleep stages and in all body positions. The majority of UDP patients were found to have clinically significant reductions in mean forced expiratory volume in one second and forced vital capacity values, consistent with restrictive ventilatory pattern. CONCLUSION: We observed an association between UDP and increasing SDB severity, particularly during REM sleep and while sleeping in the supine position. Although we identified weaknesses in study design and lack of perioperative data, anesthesiologists should be aware of this association when considering proximal brachial plexus blockade in patients with SDB.

RéSUMé: CONTEXTE: La paralysie diaphragmatique unilatérale (PDU) peut potentiellement aggraver les troubles respiratoires du sommeil (TRS). La PDU est associée aux blocs du plexus brachial proximal, tel que les blocs interscalénique et supraclaviculaire. L'impact de la PDU chez les patients atteints de TRS n'est pas connu dans ce contexte. Les objectifs de cette revue exploratoire étaient d'explorer les associations entre la PDU et l'aggravation de la sévérité des TRS, l'oxygénation, et la fonction pulmonaire. MéTHODE: Une recherche systématique a été mise au point, évaluée par des pairs et appliquée aux bases de données Embase, Medline, CINAHL et Cochrane afin d'inclure les études portant sur des patients adultes (≥ 18 ans) atteints de TRS, où les effets d'une PDU sur la sévérité des TRS, sur l'oxygénation et la fonction pulmonaire étaient examinés. RéSULTATS: Six études (n = 100 patients) portant sur la PDU et les TRS ont été incluses. La population étudiée provenait exclusivement de cliniques de respirologie-sommeil, et ne comptait aucun patient chirurgical. Comparativement au groupe témoin (aucune PDU), la PDU a été associée à un index accru de troubles respiratoires, lesquels étaient les plus prononcés pendant le sommeil paradoxal et en position de décubitus dorsal. Le sommeil en décubitus dorsal et le sommeil paradoxal ont été associés à des événements obstructifs et mixtes (obstructifs et centraux), respectivement. Comparativement au groupe témoin, la PDU a été associée à une saturation en oxygène et à une tension artérielle d'oxygène moyennes et minimales inférieures pendant tous les stades de sommeil et dans toutes les positions. Chez la majorité des patients atteints de PDU, des réductions cliniquement significatives des valeurs du volume expiratoire forcé moyen en une seconde et de la capacité vitale forcée ont été observées, des données compatibles avec une physiologie respiratoire restrictive. CONCLUSION: Nous avons observé une association entre la paralysie diaphragmatique unilatérale et une sévérité augmentée des troubles respiratoires du sommeil, particulièrement pendant le sommeil paradoxal et en décubitus dorsal. Malgré l'identification de faiblesses dans la conception des études et d'un manque de données périopératoires, les anesthésiologistes devraient garder à l'esprit cette association lorsqu'ils envisagent un bloc du plexus brachial proximal chez les patients souffrant de TRS.

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

BACKGROUND: Obstructive sleep apnea (OSA) patients are at increased risk for pulmonary and cardiovascular complications; perioperative mortality risk is unclear. This report analyzes cases submitted to the OSA Death and Near Miss Registry, focusing on factors associated with poor outcomes after an OSA-related event. We hypothesized that more severe outcomes would be associated with OSA severity, less intense monitoring, and higher cumulative opioid doses. METHODS: Inclusion criteria were age ≥18 years, OSA diagnosed or suspected, event related to OSA, and event occurrence 1992 or later and <30 days postoperatively. Factors associated with death or brain damage versus other critical events were analyzed by tests of association and odds ratios (OR; 95% confidence intervals [CIs]). RESULTS: Sixty-six cases met inclusion criteria with known OSA diagnosed in 55 (83%). Patients were middle aged (mean = 53, standard deviation [SD] = 15 years), American Society of Anesthesiologists (ASA) III (59%, n = 38), and obese (mean body mass index [BMI] = 38, SD = 9 kg/m); most had inpatient (80%, n = 51) and elective (90%, n = 56) procedures with general anesthesia (88%, n = 58). Most events occurred on the ward (56%, n = 37), and 14 (21%) occurred at home. Most events (76%, n = 50) occurred within 24 hours of anesthesia end. Ninety-seven percent (n = 64) received opioids within the 24 hours before the event, and two-thirds (41 of 62) also received sedatives. Positive airway pressure devices and/or supplemental oxygen were in use at the time of critical events in 7.5% and 52% of cases, respectively. Sixty-five percent (n = 43) of patients died or had brain damage; 35% (n = 23) experienced other critical events. Continuous central respiratory monitoring was in use for 3 of 43 (7%) of cases where death or brain damage resulted. Death or brain damage was (1) less common when the event was witnessed than unwitnessed (OR = 0.036; 95% CI, 0.007-0.181; P < .001); (2) less common with supplemental oxygen in place (OR = 0.227; 95% CI, 0.070-0.740; P = .011); (3) less common with respiratory monitoring versus no monitoring (OR = 0.109; 95% CI, 0.031-0.384; P < .001); and (4) more common in patients who received both opioids and sedatives than opioids alone (OR = 4.133; 95% CI, 1.348-12.672; P = .011). No evidence for an association was observed between outcomes and OSA severity or cumulative opioid dose. CONCLUSIONS: Death and brain damage were more likely to occur with unwitnessed events, no supplemental oxygen, lack of respiratory monitoring, and coadministration of opioids and sedatives. It is important that efforts be directed at providing more effective monitoring for OSA patients following surgery, and clinicians consider the potentially dangerous effects of opioids and sedatives-especially when combined-when managing OSA patients postoperatively.

Anesthetic Management of Narcolepsy Patients During Surgery: A Systematic Review.

BACKGROUND: Narcolepsy is a rare sleep disorder characterized by excessive daytime sleepiness, sleep paralysis, and/or hypnagogic/hypnopompic hallucinations, and in some cases cataplexy. The response to anesthetic medications and possible interactions in narcolepsy patients is unclear in the perioperative period. In this systematic review, we aim to evaluate the current evidence on the perioperative outcomes and anesthetic considerations in narcolepsy patients. METHODS: Electronic literature search of Medline, Medline in-process, Embase, Cochrane Database of Systematic Reviews databases, international conference proceedings, and abstracts was conducted in November 2015 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols guideline. A total of 3757 articles were screened using a 2-stage strategy (title-abstract followed by full text). We included case studies/series, cohort studies, and randomized controlled trials of narcolepsy patients undergoing surgical procedures under anesthesia or sedation. Preoperative narcolepsy symptoms and sleep study data, anesthetic technique, and perioperative complications were extracted. Screening of articles, data extraction, and compilation were conducted by 2 independent reviewers and any conflict was resolved by the senior author. RESULTS: A total of 19 studies including 16 case reports and 3 case series were included and evaluated. The majority of these patients received general anesthesia, whereas a small percentage of patients received regional anesthesia. Reported complications of narcolepsy patients undergoing surgeries were mainly related to autonomic dysregulation, or worsening of narcolepsy symptoms intra/postoperatively. Narcolepsy symptoms worsened only in those patient populations where the preoperative medications were either discontinued or reduced (mainly in obstetric patients). In narcolepsy patients, use of depth of anesthesia monitoring and total intravenous technique may have some advantage in terms of safety profile. Several patients undergoing neurosurgery involving the hypothalamus or third or four ventricles developed new-onset narcolepsy. CONCLUSIONS: We found a paucity of prospective clinical trials in this patient population, as most of the studies were case reports or observational studies. Continuation of preoperative medications, depth of anesthesia monitoring, use of multimodal analgesia with short-acting agents and regional anesthesia techniques were associated with favorable outcomes. Obstetric patients may be at greater risk for worsening narcolepsy symptoms, possibly related to a reduction or discontinuation of medications. For neurosurgical procedures involving the hypothalamus or third and fourth ventricle, postoperative considerations should include monitoring for symptoms of narcolepsy. Future studies are needed to better define perioperative risks associated with anesthesia and surgery in this population of patients.

Oxidative Stress and Inflammation Differentially Elevated in Objective Versus Habitual Subjective Reduced Sleep Duration in Obstructive Sleep Apnea.

STUDY OBJECTIVES: Data have demonstrated adverse health effects of sleep deprivation. We postulate that oxidative stress and systemic inflammation biomarkers will be elevated in relation to short-term and long-term sleep duration reduction. METHODS: We analyzed data from the baseline examination of a randomized controlled trial involving participants with moderate to severe obstructive sleep apnea (OSA). Baseline polysomnography provided the total sleep time (PSG-TST, primary predictor); self-reported habitual sleep duration (SR-HSD) data was collected. Morning measures of oxidative stress and systemic inflammation included: myeloperoxidase (MPO, pmol/L), oxidized low-density lipoprotein (ox-LDL, U/L), F2-isoprostane (ng/mg), paraoxonase 1 (PON1, nmol·min(-1)·mL(-1)), and aryl esterase (µmol·min(-1)·mL(-1)). Linear models adjusted for age, sex, race, body mass index (BMI), cardiovascular disease (CVD), smoking, statin/anti-inflammatory medications, and apnea-hypopnea index were utilized (beta estimates and 95% confidence intervals). RESULTS: One hundred forty-seven participants comprised the final analytic sample; they were overall middle-aged (51.0 ± 11.7 y), obese (BMI = 37.3 ± 8.1 kg/m(2)), and 17% had CVD. Multivariable models demonstrated a significant inverse association of PSG-TST and MPO (ß [95% CI] = -20.28 [-37.48, -3.08], P = 0.021), i.e., 20.3 pmol/L MPO reduction per hour increase PSG-TST. Alternatively, a significant inverse association with ox-LDL and SR-HSD was observed (ß [95% CI] = 0.98 [0.96, 0.99], P = 0.027), i.e., 2% ox-LDL reduction per hour increase SR-HSD. CONCLUSIONS: Even after consideration of obesity and OSA severity, inverse significant findings were observed such that reduced PSG-TST was associated with elevated MPO levels and SR-HSD with ox-LDL, suggesting differential up-regulation of oxidative stress and pathways of inflammation in acute versus chronic sleep curtailment. CLINICAL TRIAL REGISTRATION: NIH clinical trials registry number NCT00607893.

Does Obstructive Sleep Apnea Influence Perioperative Outcome? A Qualitative Systematic Review for the Society of Anesthesia and Sleep Medicine Task Force on Preoperative Preparation of Patients with Sleep-Disordered Breathing.

Obstructive sleep apnea (OSA) is a commonly encountered problem in the perioperative setting even though many patients remain undiagnosed at the time of surgery. The objective of this systematic review was to evaluate whether the diagnosis of OSA has an impact on postoperative outcomes. We performed a systematic review of studies published in PubMed-MEDLINE, MEDLINE In-Process, and other nonindexed citations, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Health Technology Assessment up to November 2014. Studies of adult patients with a diagnosis of OSA or high risk thereof, published in the English language, undergoing surgery or procedures under anesthesia care, and reporting ≥1 postoperative outcome were included. Overall, the included studies reported on 413,304 OSA and 8,556,279 control patients. The majority reported worse outcomes for a number of events, including pulmonary and combined complications, among patients with OSA versus the reference group. The association between OSA and in-hospital mortality varied among studies; 9 studies showed no impact of OSA on mortality, 3 studies suggested a decrease in mortality, and 1 study reported increased mortality. In summary, the majority of studies suggest that the presence of OSA is associated with an increased risk of postoperative complications.

Perioperative Complications in Obstructive Sleep Apnea Patients Undergoing Surgery: A Review of the Legal Literature.

BACKGROUND: Obstructive sleep apnea (OSA) is common in patients undergoing surgery. OSA, known or suspected, has been associated with significant perioperative adverse events, including severe neurologic injury and death. This study was undertaken to assess the legal consequences associated with poor outcomes related to OSA in the perioperative setting. METHODS: A retrospective review of the legal literature was performed by searching 3 primary legal databases between the years 1991 and 2010 for cases involving adults with known or suspected OSA who underwent a surgical procedure associated with an adverse perioperative outcome. OSA had to be directly implicated in the outcome, and surgical mishaps (i.e., uncontrolled bleeding) were excluded. The adverse perioperative outcome had to result in a lawsuit that was then adjudicated in a court of law with a final decision rendered. Data were abstracted from each case regarding patient demographics, type of surgery, type and location of adverse event, associated anesthetic and opioid use, and legal outcome. RESULTS: Twenty-four cases met the inclusion criteria. The majority (83%) occurred in or after 2007. Patients were young (average age, 41.7 years), male (63%), and had a known diagnosis of OSA (96%). Ninety-two percent of cases were elective with 33.3% considered general procedures, 37.5% were ears, nose and throat procedures for the treatment of OSA, and 29.1% were considered miscellaneous interventions. Complications occurred intraoperatively (21%), in the postanesthesia care unit (33%), and on the surgical floors (46%). The most common complications were respiratory arrest in an unmonitored setting and difficulty in airway management. Immediate adverse outcomes included death (45.6%), anoxic brain injury (45.6%), and upper airway complications (8%). Overall, 71% of the patients died, with 6 of the 11 who suffered anoxic brain injury dying at an average of 113 days later. The use of opioids and general anesthetics was believed to play a role in 38% and 58% of cases, respectively. Verdicts favored the plaintiffs in 58% of cases and the defendants in 42%. In cases favoring the plaintiff, the average financial penalty was $2.5 million (±$2.3 million; range, $650,000--$7.7 million). CONCLUSIONS: Perioperative complications related to OSA are increasingly being reported as the central contention of malpractice suits. These cases can be associated with severe financial penalties. These data likely underestimate the actual medicolegal burden, given that most such cases are settled out of court and are not accounted for in the legal literature.

Validation of the STOP-Bang Questionnaire as a Screening Tool for Obstructive Sleep Apnea among Different Populations: A Systematic Review and Meta-Analysis.

BACKGROUND: Diagnosing obstructive sleep apnea (OSA) is clinically relevant because untreated OSA has been associated with increased morbidity and mortality. The STOP-Bang questionnaire is a validated screening tool for OSA. We conducted a systematic review and meta-analysis to determine the effectiveness of STOP-Bang for screening patients suspected of having OSA and to predict its accuracy in determining the severity of OSA in the different populations. METHODS: A search of the literature databases was performed. Inclusion criteria were: 1) Studies that used STOP-Bang questionnaire as a screening tool for OSA in adult subjects (>18 years); 2) The accuracy of the STOP-Bang questionnaire was validated by polysomnography--the gold standard for diagnosing OSA; 3) OSA was clearly defined as apnea/hypopnea index (AHI) or respiratory disturbance index (RDI) ≥ 5; 4) Publications in the English language. The quality of the studies were explicitly described and coded according to the Cochrane Methods group on the screening and diagnostic tests. RESULTS: Seventeen studies including 9,206 patients met criteria for the systematic review. In the sleep clinic population, the sensitivity was 90%, 94% and 96% to detect any OSA (AHI ≥ 5), moderate-to-severe OSA (AHI ≥15), and severe OSA (AHI ≥30) respectively. The corresponding NPV was 46%, 75% and 90%. A similar trend was found in the surgical population. In the sleep clinic population, the probability of severe OSA with a STOP-Bang score of 3 was 25%. With a stepwise increase of the STOP-Bang score to 4, 5, 6 and 7/8, the probability rose proportionally to 35%, 45%, 55% and 75%, respectively. In the surgical population, the probability of severe OSA with a STOP-Bang score of 3 was 15%. With a stepwise increase of the STOP-Bang score to 4, 5, 6 and 7/8, the probability increased to 25%, 35%, 45% and 65%, respectively. CONCLUSION: This meta-analysis confirms the high performance of the STOP-Bang questionnaire in the sleep clinic and surgical population for screening of OSA. The higher the STOP-Bang score, the greater is the probability of moderate-to-severe OSA.

Attitudes regarding perioperative care of patients with OSA: a survey study of four specialties in the United States.

UNLABELLED: Obstructive sleep apnea (OSA) is a risk factor for significant perioperative complications. This national survey study sought to determine the attitudes of physicians involved in the perioperative care of OSA patients. METHODS: We modified the perioperative survey used by Turner et al. among Canadian anesthesiologists. We mailed the survey to 3,000 US physicians practicing in the following specialties (750 of each specialty): anesthesiology (A), primary care (family practice or internal medicine) (PC), sleep (SM), and general surgery (S). The survey asked questions about attitudes and practice patterns regarding OSA in the perioperative setting. RESULTS: Of 2,730 eligible subjects, 783 questionnaires (28.7 %) were returned. Overall, 94 % felt OSA was a risk factor for perioperative complications (no difference by specialty) and 90 % felt it was a moderate to major risk factor (A = 91 %, PC = 81 %, SM = 94 %, S = 72 %; p < 0.001). Fifty-two percent reported experience with a patient having an adverse outcome related to OSA in the perioperative setting. Despite this, only 71 % reported regularly screening for OSA preoperatively, mostly by history and physical examination (A = 89 %, PC = 52 %, SM = 88 %, S = 49 %; p < 0.001). If they suspected a patient of having OSA, 32 % would delay surgery pending a sleep study (A = 4 %, PC = 41 %, SM = 54 %, S = 27 %; p < 0.001), while 20 % would proceed with surgery without any special precautions (A = 22 %, PC = 21 %, SM = 5 %, S = 31 %; p < 0.001). Only 27 % of respondents reported that their hospital had a written policy for perioperative care of OSA patients. CONCLUSIONS: The majority of physicians in this survey felt OSA was a significant risk factor for perioperative complications and most reported experience with OSA patients having an adverse outcome. Perioperative management guidelines for OSA are not available at most institutions. Further work is needed to help physicians identify and intervene on patients with OSA in the perioperative setting before adverse events develop.

Symptoms of restless legs syndrome in a palliative care population: frequency and impact.

OBJECTIVES: We hypothesized that restless legs syndrome (RLS) would be common and associated with impaired quality of life (QOL) among palliative care outpatients. METHODS: 76 palliative care clinic patients completed the National Institutes of Health restless legs syndrome (NIH-RLS) screening questionnaire. Questionnaire data was also gathered on RLS severity and RLS-related QOL, and the Short Form Health Survey (SF-12) was used to measure QOL. Analysis was performed for associations between RLS categorization and QOL measures. RESULTS: 31 patients (40.8 percent) met criteria for RLS. RLS-positive patients had moderate-to-severe RLS symptoms and impaired RLS-specific QOL. RLS-positive patients scored lower on the mental component of the SF-12 (39 +/- 11 versus 45 +/- 12, p=0.03), though not on the physical component. In a multivariate regression analysis, higher levels of RLS severity had 2-point lower SF-12 mental component scores compared to lower levels of RLS severity (p=0.04), with no difference in physical component scores (p=0.47). CONCLUSION: RLS appears common in palliative care outpatients and is associated with impairments in QOL.

Preoperative screening and perioperative care of the patient with sleep-disordered breathing.

PURPOSE OF REVIEW: Emerging data are raising concerns that patients with known or suspected obstructive sleep apnea (OSA) are at increased risk for a myriad of perioperative complications. Strategies to identify patients preoperatively with OSA, or at risk for OSA, are being advocated. In addition, approaches to identify patients most at risk for OSA-related postoperative complications have been described. While lacking solid evidence, a number of perioperative management strategies have been proposed for the care of these patients. RECENT FINDINGS: Recent studies utilizing different methodologies have provided additional evidence regarding the impact that OSA can have on postoperative outcomes, including increased risk of difficult intubations, adverse pulmonary outcomes, and delirium. Tools, such as the STOP-Bang questionnaire and limited channel monitoring, have been investigated with regards to their utility to identify not only patients at risk for OSA but also those at risk for more severe OSA. Consensus-based guidelines for the perioperative care of OSA patients have recently been published. SUMMARY: OSA is quite common in patients presenting for elective surgery and has been linked to increased perioperative complications. Attempts to identify these patients preoperatively appear prudent. Protocols on how best to manage these patients are available, although validation of their effectiveness is needed.