False positive urine amphetamine immunoassay due to solriamfetol.

Solriamfetol is a schedule IV-controlled substance used to treat excessive daytime sleepiness resulting from narcolepsy or obstructive sleep apnea. We present a patient prescribed solriamfetol who tested positive for amphetamines on a routine urinary toxicology screen despite patient denial of illicit drug use, raising the possibility of a false positive amphetamine screen. Spiking studies were performed on negative urine, and different concentrations of solriamfetol drug on 2 different amphetamine assays: the commonly used Beckman Emit® II Plus Amphetamines Assay, and the Citrine™ Triple Quad™ MS/MS Systems. The Beckman yielded positive results for amphetamines at solriamfetol concentrations of 200 µg/mL and 2000 µg/mL and negative results at 0.2 µg/mL and 2 µg/mL. However, the Citrine™ Triple Quad™ MS/MS Systems was negative at all concentrations. The Beckman Emit® II Plus Amphetamine Assay gave false positive results for amphetamines due to solriamfetol drug usage, a finding of relevance to prescribers of solriamfetol.

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.

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.

Level of Evidence of Guidelines for Perioperative Management of Patients With Obstructive Sleep Apnea: An Evaluation Using the Appraisal of Guidelines for Research and Evaluation II Tool.

Currently, the quality of guidelines for the perioperative management of patients with obstructive sleep apnea (OSA) is unknown, leaving anesthesiologists to make perioperative management decisions with some degree of uncertainty. This study evaluated the quality of clinical practice guidelines regarding the perioperative management of patients with OSA. This study was reported in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic search of the MedlineALL (Ovid) database was conducted from inception to February 26, 2021, for clinical practice guidelines in the English language. Quality appraisal of guidelines was evaluated using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) framework. Descriptive statistical analysis of each of the 6 domains was expressed as a percentage using the formula: (obtained score - minimum possible score)/(maximum possible score - minimum possible score). Of 192 articles identified in the search, 41 full texts were assessed for eligibility, and 10 articles were included in this review. Intraclass correlation coefficients of the AGREE II scores across the 7 evaluators for each guideline were each >0.9, suggesting that the consistency of the scores among evaluators was high. Sixty percent of recommendations were based on evidence using validated methods to grade medical literature, while the remainder were consensus based. The median and range scores of each domain were: (1) scope and purpose, 88% (60%-95%); (2) stakeholder involvement, 52% (30%-82%); (3) rigor of development, 67% (40%-90%); (4) clarity of presentation, 74% (57%-88%); (5) applicability, 46% (20%-73%); and (6) editorial independence, 67% (19%-83%). Only 4 guidelines achieved an overall score of >70%. This critical appraisal showed that many clinical practice guidelines for perioperative management of patients with OSA used validated methods to grade medical literature, such as Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) and Oxford classification, with lower scores for stakeholder involvement due to lack of engagement of patient partners and applicability domain due to lack of focus on the complete perioperative period such as postdischarge counseling. Future efforts should be directed toward establishing higher focus on the quality of evidence, stakeholder involvement, and applicability to the wider perioperative patient experience.

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.

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.

Dose-response relationship between positive airway pressure therapy and excessive daytime sleepiness: the HomePAP study.

STUDY OBJECTIVES: The clinical benefits of positive airway pressure (PAP) therapy for obstructive sleep apnea are assumed to require adherent PAP usage, defined by the Centers for Medicare & Medicaid Services as ≥ 4 hours of use ≥ 70% of nights. However, this definition is based on early data and does not necessarily capture improvements at subthreshold adherence. We explored dose-response relationships between PAP adherence measures and excessive daytime sleepiness from the HomePAP randomized controlled trial. METHODS: Participants aged ≥ 18 years with an apnea-hypopnea index ≥ 15 events/h and baseline sleepiness (Epworth Sleepiness Scale [ESS] ≥ 12) received PAP therapy. Data were collected at baseline, 1-month follow-up, and 3-months follow-up. Regression models and receiver operating characteristic curves evaluated PAP measures as predictors of ESS change and normalization (ESS < 10). RESULTS: In 119 participants (aged 49.4 ± 12.6 years, 66.4% male, 72.3% White), > 50% were PAP nonadherent per Centers for Medicare & Medicaid Services criteria at 3 months. The percentage of nights with PAP use ≥ 4 hours predicted ESS change (P = .023), but not when controlling for the apnea-hypopnea index. The percentage of nights with ≥ 4 hours and average PAP use provided the best discrimination for predicting ESS normalization; each 10% increase in PAP use ≥ 4 hours increased the odds of ESS normalization by 22% (P = .007); those using PAP ≥ 4 hours had a nearly 3-fold greater odds of ESS normalization (P = .025). PAP use for at least 4 hours and on 70% of nights provided the best balance between specificity (0.50) and sensitivity (0.73). CONCLUSIONS: Although subadherent PAP usage may still confer some benefit for patients with obstructive sleep apnea, adherence to current criteria confers the highest likelihood for ESS change and normalization. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Name: Portable Monitoring for Diagnosis and Management of Sleep Apnea (HomePAP); URL: https://clinicaltrials.gov/ct2/show/NCT00642486; Identifier: NCT00642486. CITATION: Pascoe M, Bena J, Andrews ND, et al. Dose-response relationship between positive airway pressure therapy and excessive daytime sleepiness: the HomePAP study. J Clin Sleep Med. 2022;18(4):1027-1034.

The differential impact of respiratory event scoring criteria on CPAP eligibility in women and men.

STUDY OBJECTIVES: Obstructive sleep apnea is more prevalent and severe in men than women. The American Academy of Sleep Medicine offers 2 definitions for scoring hypopneas: "acceptable" = associated with a ≥ 4% oxygen desaturation, adopted by Center for Medicare and Medicaid Services (CMS), and "recommended" = associated with a ≥ 3% oxygen desaturation and/or an arousal. We hypothesized that CMS vs American Academy of Sleep Medicine scoring criteria would differentially impact continuous positive airway pressure eligibility in women and men. METHODS: We conducted a retrospective review of adult diagnostic in-lab polysomnography at an urban academic institution. All polysomnographies were scored by both CMS and American Academy of Sleep Medicine scoring criteria, and an analysis by sex was performed that considered demographics and other polysomnography variables. RESULTS: Of 969 polysomnographies reviewed, 674 (69.6%) were in women. Women were younger (51.5 vs 53.3 years old) and had a higher body mass index (38.6 kg/m2 vs 33.8 kg/m2) but had similar Epworth Sleepiness Scale scores compared to men. The odds of an American Academy of Sleep Medicine apnea-hypopnea index > 5 events/h being missed by CMS scoring in women was 1.89 (95% confidence interval: 1.40-2.53; P < .001) compared to men and increased to 6.87 among women 40-60 years of age with a body mass index ≥ 40 kg/m2. After controlling for age, body mass index, % rapid eye movement sleep, and mean oxygen saturation, the sex effect remained significant (odds ratio 1.87; 95% confidence interval: 1.36-2.58; P < .001). CONCLUSIONS: CMS scoring criteria imparts a sex bias toward women, potentially resulting in denial of therapy to symptomatic women with obstructive sleep apnea. Larger, prospective cohort studies are needed to confirm these findings. CITATION: Khalid F, Ayache M, Auckley D. The differential impact of respiratory event scoring criteria on CPAP eligibility in women and men. J Clin Sleep Med. 2021;17(12):2409-2414.

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.

Prediction of Opioid-Induced Respiratory Depression on Inpatient Wards Using Continuous Capnography and Oximetry: An International Prospective, Observational Trial.

BACKGROUND: Opioid-related adverse events are a serious problem in hospitalized patients. Little is known about patients who are likely to experience opioid-induced respiratory depression events on the general care floor and may benefit from improved monitoring and early intervention. The trial objective was to derive and validate a risk prediction tool for respiratory depression in patients receiving opioids, as detected by continuous pulse oximetry and capnography monitoring. METHODS: PRediction of Opioid-induced respiratory Depression In patients monitored by capnoGraphY (PRODIGY) was a prospective, observational trial of blinded continuous capnography and oximetry conducted at 16 sites in the United States, Europe, and Asia. Vital signs were intermittently monitored per standard of care. A total of 1335 patients receiving parenteral opioids and continuously monitored on the general care floor were included in the analysis. A respiratory depression episode was defined as respiratory rate ≤5 breaths/min (bpm), oxygen saturation ≤85%, or end-tidal carbon dioxide ≤15 or ≥60 mm Hg for ≥3 minutes; apnea episode lasting >30 seconds; or any respiratory opioid-related adverse event. A risk prediction tool was derived using a multivariable logistic regression model of 46 a priori defined risk factors with stepwise selection and was internally validated by bootstrapping. RESULTS: One or more respiratory depression episodes were detected in 614 (46%) of 1335 general care floor patients (43% male; mean age, 58 ± 14 years) continuously monitored for a median of 24 hours (interquartile range [IQR], 17-26). A multivariable respiratory depression prediction model with area under the curve of 0.740 was developed using 5 independent variables: age ≥60 (in decades), sex, opioid naivety, sleep disorders, and chronic heart failure. The PRODIGY risk prediction tool showed significant separation between patients with and without respiratory depression (P < .001) and an odds ratio of 6.07 (95% confidence interval [CI], 4.44-8.30; P < .001) between the high- and low-risk groups. Compared to patients without respiratory depression episodes, mean hospital length of stay was 3 days longer in patients with ≥1 respiratory depression episode (10.5 ± 10.8 vs 7.7 ± 7.8 days; P < .0001) identified using continuous oximetry and capnography monitoring. CONCLUSIONS: A PRODIGY risk prediction model, derived from continuous oximetry and capnography, accurately predicts respiratory depression episodes in patients receiving opioids on the general care floor. Implementation of the PRODIGY score to determine the need for continuous monitoring may be a first step to reduce the incidence and consequences of respiratory compromise in patients receiving opioids on the general care floor.

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.

Evaluation of an OSA risk stratifying and treatment protocol during inpatient rehabilitation of post-stroke patients.

PURPOSE: To evaluate outcomes, outside of a clinical trial setting, of a protocol utilizing overnight oximetry (NOx) to risk stratify post-stroke patients for obstructive sleep apnea (OSA) followed by autoadjusting continuous positive airway pressure (APAP) treatment in patients considered high risk for OSA. METHODS: Retrospective observational study of post-stroke patients at an academic inpatient stroke rehabilitation facility. Patients underwent NOx, and those at high risk for OSA (oxygen desaturation index 3% > 10 per hour) were attempted on a trial of APAP, and further stratified into high risk adherent with treatment (HRAT) or high-risk failed treatment (HRFT). Change in functional independence measure (FIM) was used to assess recovery. RESULTS: Two hundred twenty-four post-stroke patients underwent NOx, with 120 (53%) considered high risk for OSA. Twelve (10%) were compliant with APAP treatment (> 4 h/night on > 70% of nights). No difference in change in FIM scores was observed for HRAT versus HRFT [total FIM change - 5.8, 95% CI (- 13.9, 2.2); motor FIM change - 4.5, 95% CI (- 11.5, 2.4); cognitive FIM change - 1.3, 95% CI (-3.8, 1.2)]. A subgroup analysis matched 14 HRAT patients (using adherence criterion of APAP usage > 50% of nights) to 35 HRFT patients. A statistically significant, but clinically irrelevant, difference in total FIM change was observed (HRAT vs HRFT, difference between means - 5.2, p = 0.03). CONCLUSIONS: The use of APAP in high-risk patients was poorly tolerated and did not improve post-stroke recovery. Further studies with larger sample sizes are needed to determine the effect of APAP treatment on short-term recovery.