Patients with a high risk for obstructive sleep apnea syndrome: postoperative respiratory complications

Effect of obstructive sleep apnea on postoperative delirium: a system review and meta-analysis

PURPOSE

To investigate the impact of obstructive sleep apnea (OSA) on postoperative delirium (PD), and evaluate the effectiveness of positive airway pressure (PAP) therapy on PD among OSA patients.

METHODS

We systematically searched Embase, Cochrane Library and PubMed databases from their establishment to November 27, 2022. A random-effects approach was employed to determine aggregated results. Subgroup and sensitivity analyses were carried out to investigate heterogeneity.

RESULTS

Sixteen eligible studies were included in the analysis. Thirteen studies revealed that OSA significantly elevated the likelihood of developing PD (OR = 1.71; 95%CI = 1.17 to 2.49; p = 0.005). Subgroup analysis according to delirium assessment scales showed that OSA did not exhibit an association with the incidence of PD assessed by the Confusion Assessment Method-Intensive Care Unit (OR = 1.14; 95%CI = 0.77 to 1.67; p = 0.51) but enhanced the likelihood of developing PD evaluated with other measurement scales (OR = 2.15; 95%CI = 1.44 to 3.19; p = 0.0002). Three additional studies explored the impact of PAP treatment on PD among OSA individuals, indicating no significant reduction in PD incidence with PAP use (OR = 0.58; 95%CI = 0.13 to 2.47; p = 0.46).

CONCLUSIONS

OSA may not be a risk factor for PD in critically ill patients in the intensive care unit, but may increase the likelihood of developing PD among individuals receiving regular care in the ward postoperatively. The efficacy of PAP therapy in decreasing PD incidence among OSA patients remains debatable.

Perioperative Pulmonary Complications in the Elderly: The Forgotten System

With a rapidly aging population and increasing global surgical volumes, managing the elevated risk of perioperative pulmonary complications has become an expanding focus for quality improvement in health care. In this narrative review, we will analyze the evidence-based literature to provide high-quality and actionable management strategies to better detect, stratify risk, optimize, and manage perioperative pulmonary complications in geriatric populations.

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.

Preoperative screening of patients at high risk of obstructive sleep apnea and postoperative complications: A systematic review and meta-analysis

STUDY OBJECTIVE

To determine the association between postoperative complications and a high versus low risk of obstructive sleep apnea (OSA) as determined via screening tools.

DESIGN

Systematic review and meta-analysis of cohort studies. PubMed, EMBASE, Web of Science, and the Cochrane Library were searched from their inception to January 5, 2021.

SETTING

Operating room, postoperative recovery area, and ward.

PATIENTS

Adult patients scheduled for surgery.

INTERVENTIONS

We used Review Manager 5.4 to pool the data. The quality of evidence was rated using the Grading of Recommendations, Assessment, Development and Evaluation system.

MEASUREMENTS

The primary outcome was the composite endpoint of postoperative respiratory complications. The secondary outcomes were postoperative cardiac and neurological complications, intensive care unit (ICU) admission, and mortality.

MAIN RESULTS

Twenty-six studies with 50,592 patients were included. A STOP-Bang score ≥ 3 (versus <3) was associated with higher incidences of postoperative respiratory (odds ratio [OR], 2.11; 95% confidence interval [CI], 1.66-2.68) and neurological complications (OR, 3.60; 95% CI, 1.56-8.31). A STOP-Bang score ≥ 5 (versus <5) was associated with higher incidences of postoperative respiratory (OR, 2.37; 95% CI, 1.11-5.04) and cardiac complications (OR, 4.95; 95% CI, 1.22-20.00) and higher in-hospital mortality (OR, 26.39; 95% CI, 2.89-241.30). A Berlin score ≥ 2 (versus <2) was not associated with the incidence of postoperative complications, ICU admission, or mortality. The quality of evidence for all outcomes was very low.

CONCLUSIONS

Very low-quality evidence suggested that a high risk of OSA, as assessed using the STOP-Bang questionnaire, was associated with a higher incidence of postoperative respiratory complications, and may also be associated with higher incidences of postoperative cardiac and neurological complications than a low risk of OSA. Since most of the included studies did not adjust for confounding factors, our findings need to be interpreted with caution. PROSPERO registration number: CRD42021220236.

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.

Modified STOP-Bang for predicting perioperative adverse events in the Thai population

Background

Undiagnosed obstructive sleep apnea (OSA) is associated with adverse perioperative outcomes. The STOP-Bang questionnaire is a validated screening tool for OSA. However, its precision may vary among different populations. This study determined the association between high-risk OSA based on the modified STOP-Bang questionnaire and perioperative adverse events.

Methods

This cross-sectional study included patients undergoing elective surgery from December 2018 to February 2019. The modified STOP-Bang questionnaire includes a history of Snoring, daytime Tiredness, Observed apnea, high blood Pressure, Body mass index > 30 kg/m², Age > 50, Neck circumference > 40 cm, and male Gender. High risk for OSA was considered as a score ≥ 3.

Results

Overall, 400 patients were included, and 18.3% of patients experienced perioperative adverse events. On the basis of modified STOP-Bang, the incidence of perioperative adverse events was 23.2 and 13.8% in patients with high risk and low risk (P-value 0.016) (Original STOP-Bang: high risk 22.5% vs. low risk 14.7%, P-value 0.043). Neither modified nor original STOP-Bang was associated with perioperative adverse events (adjusted OR 1.91 (95% CI 0.99–3.66), P-value 0.055) vs. 1.69 (95%CI, 0.89–3.21), P-value 0.106). Modified STOP-Bang ≥3 could predict the incidence of difficult ventilation, laryngoscopic view ≥3, need for oxygen therapy during discharge from postanesthetic care unit and ICU admission.

Conclusions

Neither modified nor original STOP-Bang was significantly associated with perioperative adverse events. However, a modified STOP-Bang ≥3 can help identify patients at risk of difficult airway, need for oxygen therapy, and ICU admission.

Trial registrations

This study was registered on Thai Clinical Trials Registry, identifier TCTR20181129001, registered 23 November 2018 (Prospectively registered).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01347-0.

NAFLD and liver transplantation: Disease burden, current management and future challenges

Non-alcoholic fatty liver disease (NAFLD), specifically its progressive form non-alcoholic steatohepatitis (NASH), represents the fastest growing indication for liver transplantation in Western countries. Diabetes mellitus, morbid obesity and cardiovascular disease are frequently present in patients with NAFLD who are candidates for liver transplantation. These factors require specific evaluation, including a detailed pre-surgical risk stratification, in order to improve outcomes after liver transplantation. Moreover, in the post-transplantation setting, the incidence of cardiovascular events and metabolic complications can be amplified by immunosuppressive therapy, which is a well-known driver of metabolic alterations. Indeed, patients with NASH are more prone to developing early post-transplant complications and, in the long-term, de novo malignancy and cardiovascular events, corresponding to higher mortality rates. Therefore, a tailored multidisciplinary approach is required for these patients, both before and after liver transplantation. Appropriate candidate selection, lifestyle modifications and specific assessment in the pre-transplant setting, as well as pharmacological strategies, adjustment of immunosuppression and a healthy lifestyle in the post-transplant setting, play a key role in correct management.

Society of Anesthesia and Sleep Medicine Guideline on Intraoperative Management of Adult Patients With Obstructive Sleep Apnea

The purpose of the Society of Anesthesia and Sleep Medicine Guideline on Intraoperative Management of Adult Patients With Obstructive Sleep Apnea (OSA) is to present recommendations based on current scientific evidence. This guideline seeks to address questions regarding the intraoperative care of patients with OSA, including airway management, anesthetic drug and agent effects, and choice of anesthesia type. Given the paucity of high-quality studies with regard to study design and execution in this perioperative field, recommendations were to a large part developed by subject-matter experts through consensus processes, taking into account the current scientific knowledge base and quality of evidence. This guideline may not be suitable for all clinical settings and patients and is not intended to define standards of care or absolute requirements for patient care; thus, assessment of appropriateness should be made on an individualized basis. Adherence to this guideline cannot guarantee successful outcomes, but recommendations should rather aid health care professionals and institutions to formulate plans and develop protocols for the improvement of the perioperative care of patients with OSA, considering patient-related factors, interventions, and resource availability. Given the groundwork of a comprehensive systematic literature review, these recommendations reflect the current state of knowledge and its interpretation by a group of experts at the time of publication. While periodic reevaluations of literature are needed, novel scientific evidence between updates should be taken into account. Deviations in practice from the guideline may be justifiable and should not be interpreted as a basis for claims of negligence.

Preoperative Evaluation: Estimation of Pulmonary Risk Including Obstructive Sleep Apnea Impact

One in 4 deaths occurring within a week of surgery are related to pulmonary complications, making it the second most common serious morbidity after cardiovascular events. The most significant predictors of the postoperative pulmonary complications (PPCs) are American Society of Anesthesiologists physical status, advanced age, dependent functional status, surgical site, and duration of surgery. The overall risk of PPCs can be predicted using scores that incorporate readily available clinical data.

Investigation of intraoperative dosing patterns of neuromuscular blocking agents

There is a growing body of literature documenting the use of deep neuromuscular block (NMB) during surgery. Traditional definitions of depth of NMB rely on train-of-four assessment, which can be less reliable in retrospective studies. The goal of our study was to investigate the real-world practice pattern of dosing of neuromuscular blocking agents (NMBA), utilizing the amount of NMBA used during the course of a case, adjusted for patient weight and case duration, as a surrogate measure of depth of NMB. We also aimed to identify case factors associated with larger NMBA doses. In this retrospective observational analysis of our anesthesia information management system, we analyzed all general endotracheal anesthesia cases from 2012 to 2015 in which an intermediate-acting NMBA was used. Cases using a long-acting NMBA or only succinylcholine were excluded. The expected duration of the case was calculated based on the cumulative dose of NMB used, normalized to the patient's ideal body weight and the ED95 of the drug. If the expected duration of the case was greater than the actual case duration documented in the case record, it was classified as higher dosing (HD). If the expected duration was equal to or less than the actual duration, it was considered predicted dosing (PD). Categorical comparisons between HD and PD groups were made for various patient, procedural, and provider factors. 72,684 cases were included in the final analysis, of which 46,358, or 64% of cases, used HD. Cases with patients who were morbidly obese, younger than 65 years, and who were lower ASA Physical Status classification (I or II) used more HD as opposed to PD. Cases that were non-open, used total intravenous anesthesia, emergent cases, or used non-rapid sequence anesthesia induction had higher rates of HD than their matched counterparts. All results were statistically significant. HD was more common in cases that documented train-of-four and used the reversal agent neostigmine. Approximately two-thirds of general endotracheal anesthesia cases using an intermediate-acting NMBA used HD. Cases with higher rates of HD may be those that are traditionally technically complex or emergent, would benefit from greater paralysis, or do not use adjunctive medications for muscle relaxation. Age greater than 65 years was shown to have lower rates of HD, likely due to provider awareness of age-related changes in pharmacokinetics and pharmacodynamics. Intraoperative monitoring and NMB antagonism with neostigmine were used more frequently with HD.

An update on the various practical applications of the STOP-Bang questionnaire in anesthesia, surgery, and perioperative medicine

Purpose of review

The present review aims to provide an update on the various practical applications of the STOP-Bang questionnaire in anesthesia, surgery, and perioperative medicine.

Recent findings

The STOP-Bang questionnaire was originally validated as a screening tool to identify surgical patients who are at high-risk of obstructive sleep apnea (OSA). A recent meta-analysis confirmed that STOP-Bang is validated for use in the sleep clinic, surgical, and general population. Patients with a STOP-Bang score of 0--2 can be classified as low-risk for moderate-to-severe OSA. Those with a score of 5--8 can be classified as high-risk for moderate-to-severe OSA. In patients with a score of 3 or 4, a specific combination of a STOP score at least 2 + BMI more than 35 kg/m² or STOP score at least 2 + male or STOP score at least 2 + neck circumference more than 40 cm indicates higher risk for moderate-to-severe OSA. Further, patients with a STOP-Bang score at least 3 can be classified as high risk for moderate-to-severe OSA if the serum HCO₃^- at least 28 mmol/l. STOP-Bang can be used as a novel tool for perioperative risk stratification because it easily identifies patients who are at increased risk of perioperative complications.

Summary

STOP-Bang at least 3 was recommended previously to identify the suspected or undiagnosed OSA. To reduce the false positive cases and to improve its specificity, a stepwise stratification is recommended to identify the patients at high risk of moderate-to-severe OSA. Because of its practical application, STOP-Bang is a useful screening tool for patients with suspected or undiagnosed OSA.

Using the Electronic Medical Record to Improve Preoperative Identification of Patients at Risk for Obstructive Sleep Apnea

PURPOSE

Obstructive sleep apnea (OSA) is a breathing disorder found in surgical patients and associated with complications in the postoperative period. The implementation of a preoperative universal screening process using the STOP-BANG questionnaire to identify patients at high risk for OSA provides opportunities for improved management.

DESIGN

A pre-post design was used to evaluate screening compliance rates.

METHODS

This initiative included staff education, which included the process for evaluating and documenting STOP-BANG scores. The data were collected via a chart review of the electronic medical record (EMR).

FINDINGS

The rate of screening for OSA doubled after implementation of this initiative, and compliance with STOP-BANG questionnaire screening was 66.1%. High-risk designation in the EMR was 73.0%. Nearly half of the patients screened were found to be at high risk for OSA.

CONCLUSIONS

Implementation of a universal screening initiative for patients and design for the EMR improves compliance with screening and identification of patients at high risk for OSA.

Postoperative complications with neuromuscular blocking drugs and/or reversal agents in obstructive sleep apnea patients: a systematic review

BACKGROUND

Neuromuscular blocking drugs (NMBD) are administered intra-operatively to facilitate intubation and to achieve muscle relaxation for surgical procedures. Incomplete reversal of NMBD can lead to adverse events in the postoperative period. Patients with obstructive sleep apnea (OSA) may be at higher risk of complications related to the use of NMBD. The objectives of this systematic review were to determine whether: 1) OSA patients are at higher risk of postoperative complications from the use of NMBD than non-OSA patients, and 2) the choice of NMBD reversal agent affects the risk of postoperative complications in OSA patients.

METHODS

A literature search of multiple databases was conducted up to April 2017. The inclusion criteria were: (1) adult surgical patients (≥18 years old) with OSA diagnosed by polysomnography, or history, or suspected by screening questionnaire; (2) patients who were given NMBD and/or NMBD reversal agents intraoperatively; (3) reports on postoperative adverse events, particularly respiratory events were available; (4) published studies were in English; and (5) RCTs or observational cohort studies. The quality of evidence was determined by the Oxford Center for Evidence Based Medicine levels of evidence.

RESULTS

Out of 4123 studies, five studies (2 RCTs and 3 observational studies) including 1126 patients were deemed eligible. These studies were heterogeneous precluding a meta-analysis of the results. Two of three studies (1 RCT, 2 observational studies) reported that OSA patients given NMBD may be at higher risk of developing postoperative pulmonary complications (PPCs) like hypoxemia, residual neuromuscular blockade or respiratory failure compared to non-OSA patients. Two studies (1 RCT, 1 observational study) reported that OSA patients who were reversed with sugammadex vs. neostigmine had less PPCs and chest radiographic changes, but the quality of the included studies was Oxford level of evidence: low to moderate.

CONCLUSIONS

OSA patients who receive intraoperative NMBD may be at higher risk for postoperative hypoxemia, respiratory failure and residual neuromuscular blockade compared to non-OSA patients. There is some, albeit very limited evidence that NMBD reversal with sugammadex may be associated with less PPCs than neostigmine in patients with OSA. More high-quality studies are needed.

Inflammation is related to preoperative hypoxemia in patients with acute Stanford type A aortic dissection

Background

Preoperative hypoxemia is a frequent complication of acute Stanford type A aortic dissection (ATAAD). The aim of the present study was to determine which factors were associated with hypoxemia.

Methods

A series of data were collected in a statistical analysis to evaluate preoperative hypoxemia in patients with ATAAD. After retrospectively analyzing data for 172 patients, we identified the risk factors for preoperative hypoxemia. Hypoxemia was defined by an arterial partial pressure of oxygen to fraction of inspired oxygen (PaO₂/FiO₂) ratio of 200 or lower. Subsequent to identifying the patient population, a prospective study was conducted using ulinastatin as a preoperative intervention. The ulinastatin group received ulinastatin at a total dose of 300,000 units prior to surgery. All the pertinent factors were investigated through univariate and multiple logistic regression analysis.

Results

The factors associated with preoperative hypoxemia in ATAAD comprised the following: body mass index (BMI) ≥25; white blood cell count (WBC) and neutrophil counts; levels of C-reactive protein (CRP), D-dimer, and interleukin-6 (IL-6); ATAAD involving the celiac trunk, renal artery, or mesenteric artery. Logistic regression analysis showed that CRP and IL-6 levels were independent predictive factors. We found that ulinastatin effectively could improve oxygenation, since compared to the control group the oxygenation in the ulinastatin group was significantly improved.

Conclusions

Systemic inflammatory reactions played a vital role in preoperative hypoxemia after the onset of ATAAD. The oxygenation of the patient could be improved significantly by inhibiting the inflammatory response prior to surgery.

Overnight in-hospital observation following tonsillectomy: retrospective study of post-operative intervention

OBJECTIVE

The safety of day-case tonsillectomy is widely documented in the literature; however, there are no evidence-based guidelines recommending patient characteristics that are incompatible with day-case tonsillectomy. This study aimed to identify which patients should be considered unsafe for day-case tonsillectomy based on the likelihood of needing critical intervention.

METHOD

Retrospective review of 2863 tonsillectomy procedures performed at University Hospital Geelong from 1998 to 2014.

RESULTS

Of the patients, 7.81 per cent suffered a post-tonsillectomy complication and 4.15 per cent required intervention. The most serious complications, haemorrhage requiring a return to the operating theatre and airway compromise, occurred in 0.56 per cent and 0.11 per cent of patients respectively. The following patient characteristics were significantly associated with poorer outcomes: age of two years or less (p < 0.01), tonsillectomy indicated for neoplasm (p < 0.01) and quinsy (p < 0.05).

CONCLUSION

The authors believe that all elective tonsillectomy patients should be considered for day-case surgery, with the following criteria necessitating overnight observation: age of two years or less; an indication for tonsillectomy of neoplasm or quinsy; and an American Society of Anesthesia score of more than 2.

Association of STOP-Bang Questionnaire as a Screening Tool for Sleep Apnea and Postoperative Complications: A Systematic Review and Bayesian Meta-analysis of Prospective and Retrospective Cohort Studies

BACKGROUND

The risk of postoperative complications increases with undiagnosed obstructive sleep apnea (OSA). The high-risk OSA (HR-OSA) patients can be easily identified using the STOP-Bang screening tool. The aim of this systematic review and meta-analysis is to determine the association of postoperative complications in patients screened as HR-OSA versus low-risk OSA (LR-OSA).

METHODS

The following data bases were searched from January 1, 2008, to October 31, 2016, to identify the eligible articles: Cochrane Central Register of Controlled Trials, MEDLINE, PubMed, Cochrane Databases of Systematic Reviews, Medline-in-Process & other nonindexed citations, Google Scholar, Embase, Web of Sciences and Scopus. The search included studies with adult surgical patients screened for OSA with STOP-Bang questionnaire that reported at least 1 cardiopulmonary or any other complication requiring intensive care unit admission as diagnosis of outcome. We used a Bayesian random-effects analysis to evaluate the existing evidence of STOP-Bang in relation to OSA and to assess the association of postoperative complications with the identified HR-OSA patients by study design and methodologies.

RESULTS

This systematic review and meta-analysis was conducted using 10 cohort studies: 23,609 patients (HR-OSA, 7877; LR-OSA, 15,732). The pooled odds of perioperative complications were higher in the HR-OSA versus LR-OSA patients (odds ratio 3.93, 95% credible interval, 1.85-7.77, P= .003; 6.86% vs 4.62%). The length of hospital stay was longer in HR-OSA by 2 days when compared with LR-OSA (5.0 ± 4.2 vs 3.4 ± 2.8 days; mean difference 2.01; 95% credible interval, 0.77-3.24; P= .005). Meta-regression to adjust for baseline confounding factors and subgroup analysis did not materially change the results.

CONCLUSIONS

This systematic review and meta-analysis suggests that HR-OSA is related with higher risk of postoperative adverse events and longer length of hospital stay when compared with LR-OSA patients. Our findings support the implementation of the STOP-Bang screening tool for perioperative risk stratification.

Trends in Perioperative Practice and Resource Utilization in Patients With Obstructive Sleep Apnea Undergoing Joint Arthroplasty

BACKGROUND

Emerging evidence associating obstructive sleep apnea (OSA) with adverse perioperative outcomes has recently heightened the level of awareness among perioperative physicians. In particular, estimates projecting the high prevalence of this condition in the surgical population highlight the necessity of the development and adherence to "best clinical practices." In this context, a number of expert panels have generated recommendations in an effort to provide guidance for perioperative decision-making. However, given the paucity of insights into the status of the implementation of recommended practices on a national level, we sought to investigate current utilization, trends, and the penetration of OSA care-related interventions in the perioperative management of patients undergoing lower joint arthroplasties.

METHODS

In this population-based analysis, we identified 1,107,438 (Premier Perspective database; 2006-2013) cases of total hip and knee arthroplasties and investigated utilization and temporal trends in the perioperative use of regional anesthetic techniques, blood oxygen saturation monitoring (oximetry), supplemental oxygen administration, positive airway pressure therapy, advanced monitoring environments, and opioid prescription among patients with and without OSA.

RESULTS

The utilization of regional anesthetic techniques did not differ by OSA status and overall <25% and 15% received neuraxial anesthesia and peripheral nerve blocks, respectively. Trend analysis showed a significant increase in peripheral nerve block use by >50% and a concurrent decrease in opioid prescription. Interestingly, while the absolute number of patients with OSA receiving perioperative oximetry, supplemental oxygen, and positive airway pressure therapy significantly increased over time, the proportional use significantly decreased by approximately 28%, 36%, and 14%, respectively. A shift from utilization of intensive care to telemetry and stepdown units was seen.

CONCLUSIONS

On a population-based level, the implementation of OSA-targeted interventions seems to be limited with some of the current trends virtually in contrast to practice guidelines. Reasons for these findings need to be further elucidated, but observations of a dramatic increase in absolute utilization with a proportional decrease may suggest possible resource constraints as a contributor.

Society of Anesthesia and Sleep Medicine Guidelines on Preoperative Screening and Assessment of Adult Patients With Obstructive Sleep Apnea

Supplemental Digital Content is available in the text.

The purpose of the Society of Anesthesia and Sleep Medicine guideline on preoperative screening and assessment of adult patients with obstructive sleep apnea (OSA) is to present recommendations based on the available clinical evidence on the topic where possible. As very few well-performed randomized studies in this field of perioperative care are available, most of the recommendations were developed by experts in the field through consensus processes involving utilization of evidence grading to indicate the level of evidence upon which recommendations were based. This guideline may not be appropriate for all clinical situations and all patients. The decision whether to follow these recommendations must be made by a responsible physician on an individual basis. Protocols should be developed by individual institutions taking into account the patients’ conditions, extent of interventions and available resources. This practice guideline is not intended to define standards of care or represent absolute requirements for patient care. The adherence to these guidelines cannot in any way guarantee successful outcomes and is rather meant to help individuals and institutions formulate plans to better deal with the challenges posed by perioperative patients with OSA. These recommendations reflect the current state of knowledge and its interpretation by a group of experts in the field at the time of publication. While these guidelines will be periodically updated, new information that becomes available between updates should be taken into account. Deviations in practice from guidelines may be justifiable and such deviations should not be interpreted as a basis for claims of negligence.

Can Screening Tools for Obstructive Sleep Apnea Predict Postoperative Complications? A Systematic Review of the Literature

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is a common, underdiagnosed condition that is associated with significant morbidity and mortality in the perioperative setting. Increasing evidence suggests that the utility of preoperative screening tools may go beyond identification of OSA, to the prediction of perioperative complications. The primary objective of this study was to systematically review the literature on all studies assessing whether high risk scores on the STOP-Bang questionnaire, American Society of Anesthesiologists (ASA) checklist, and the Berlin Questionnaire (BQ) are associated with higher rates of postoperative complications.

METHODS

A systematic review of English language records was performed using Medline, EMBASE, and PsychInfo with additional studies identified by manual search through reference lists. Only studies that evaluated the ability of the STOP-Bang, the BQ, and ASA checklist to predict postoperative complications in adults were included.

RESULTS

Twelve studies were included in the final review. Eight studies looked at STOP-Bang, 3 at the Berlin Questionnaire, and 2 at the ASA Checklist. Significant differences across study characteristics prevented a meta-analysis and the studies were evaluated qualitatively.

CONCLUSIONS

The ASA checklist, Berlin Questionnaire, and STOP-Bang questionnaire may be able to risk stratify patients for perioperative and postoperative complications. Further research is required, with a particular focus on specific surgery types and adjustment of potentially confounding factors in the analysis.

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.

Obstructive Sleep Apnea: A Risk Factor for Surgical Site Infection following Colectomy

BACKGROUND

Obstructive sleep apnea (OSA) is associated with increased systemic oxidative stress, endothelial dysfunction, and activation of pro-inflammatory cascades, which increase host susceptibility to infection. OSA has not been evaluated as a risk factor for surgical site infection (SSI) following colectomy. We hypothesized that OSA increases the risk for SSI after colectomy.

METHODS

We performed a retrospective review of 507 colectomies that took place between August 2011 and September 2013. Forty-two patients carried the diagnosis of OSA prior to surgery. These 42 patients were matched to 68 patients with no OSA for age, body mass index (BMI), diabetes mellitus (DM), reason for surgery and surgical approach.

RESULTS

The rate of SSI was 28.6% (12 of 42) in the patients with and 10.3% (7 of 68) in the patients without OSA (p=0.03). Using logistic regression, the predictors of SSI following colectomy were found to be OSA (odds ratio [OR] of 3.98, 95% confidence interval [CI]=1.29-12.27), and DM (OR of 7.16, 95% CI=2.36-21.96). The average hospital stay after colectomy for patients with OSA complicated with SSI was 16.7 d whereas patients with OSA without SSI stayed 7.4 d (p<0.001). The rate of organ space infections was 9.5% (4 of 42) in the patients with OSA compared with 0 (p=0.02) in patients without OSA.

CONCLUSIONS

OSA is an independent risk factor for SSI following colectomy. Patients with OSA have substantially greater rates of organ space SSI and longer hospital stay.

Effect of sedative-hypnotics, anesthetics and analgesics on sleep architecture in obstructive sleep apnea

The perioperative care of obstructive sleep apnea (OSA) patients is currently receiving much attention due to an increased risk for complications. It is established that postoperative changes in sleep architecture occur and this may have pathophysiological implications for OSA patients. Upper airway muscle activity decreases during rapid eye movement sleep (REMS). Severe OSA patients exhibit exaggerated chemoreceptor-driven ventilation during non-rapid eye movement sleep (NREMS), which leads to central and obstructive apnea. This article critically reviewed the literature relevant to preoperative screening for OSA, prevalence of OSA in surgical populations and changes in postoperative sleep architecture relevant to OSA patients. In particular, we addressed three questions in regard to the effects of sedative-hypnotics, anesthetics and analgesics on sleep architecture, the underlying mechanisms and the relevance to OSA. Indeed, these classes of drugs alter sleep architecture, which likely significantly contributes to abnormal postoperative sleep architecture, exacerbation of OSA and postoperative complications.

Implications and interventions related to obstructive sleep apnea

Surgical patients with known or unknown obstructive sleep apnea are at increased risk for postoperative complications. By implementing evidence-based practices and a validated screening tool, the postoperative surgical patients at the authors' hospital have a decreased risk of postoperative complications, specifically oversedation. This article discusses the pathophysiology, prevalence, risk factors, care of the postsurgical patient, and use of the validated STOP-Bang questionnaire with obstructive sleep apnea as the focus.

Early major medical complications after surgical management of obstructive sleep apnea: a retrospective cohort analysis and case series

PURPOSE

The purpose of this study was to determine the frequency and relative risk (RR) of early postoperative major medical complications after surgery for the management of obstructive sleep apnea.

PATIENTS AND METHODS

This was a retrospective cohort analysis of patients who had undergone surgery for the treatment of polysomnogram-confirmed obstructive sleep apnea at 2 hospitals in Pittsburgh, PA, between 1992 and 2013. Early postoperative major medical complications were defined as either a life-threatening complication requiring intensive care unit intervention or death within the immediate hospital course. Standard demographic data, apnea-hypopnea index, Epworth Sleepiness Score, minimum nocturnal oxygen saturation, and body mass index were collected. The 2-tailed independent t test, Fisher exact test, and RR with 95% confidence interval were used.

RESULTS

A total of 267 consecutive patients who underwent surgery for obstructive sleep apnea and met the inclusion criteria were included in this study. A total of 6 patients (6 of 267, 2.2%) had early major medical postoperative complications. When stratified by surgical group (intrapharyngeal vs extrapharyngeal), there were 162 intrapharyngeal patients with 2 complications (1.2%) and 105 extrapharyngeal patients with 4 complications (3.8%). We found no statistically significant difference in frequency (2 of 162 intrapharyngeal patients [1.2%] vs 4 of 105 extrapharyngeal patients [3.8%], P = .17) or RR (3.1; 95% confidence interval, 0.58 to 16.55; P = .1885) between the groups. There were statistically significant differences for mean age, apnea-hypopnea index, Epworth Sleepiness Score, minimum nocturnal oxygen saturation, and body mass index between the surgical groups.

CONCLUSIONS

The overall frequency of early major medical postoperative complications in upper airway surgery for obstructive sleep apnea is low, with no statistically significant difference in frequency and RR between intrapharyngeal and extrapharyngeal surgery. There may, however, be a clinically significance difference in RR possibly because of associated differences in risk factors between the groups.

Non-invasive respiratory volume monitoring to detect apnea in post-operative patients: case series

Obstructive sleep apnea (OSA) is a potential independent risk factor for postoperative complications, adverse surgical outcomes, and longer hospital stays. Obese patients with OSA have increased post-operative complications. An estimated 25-30% of pre-operative patients are at a high risk for OSA. A novel, non-invasive respiratory volume monitor (RVM) has been developed to provide a real time respiratory curve demonstrating lung volumes as well as a continuous, display of minute ventilation, tidal volume and respiratory rate. Clinical application of this device in the post-anesthesia care unit (PACU) can "unmask" post-operative apneic events resulting from partial or complete airway collapse due to the residual effects of narcotic administration and volatile and/or intravenous anesthetics. Clinical examples from two patients, one with known OSA and one without a previous diagnosis of OSA, monitored in the PACU with RVM are presented here. Post-operatively both patients had an increase in apneic episodes with significant decreases in their MV during apneic episodes after opioid administration as compared to pre-op baseline. In addition, oxygen saturation, for both patients, which is an essential component of current respiratory monitoring remained normal in the cases presented, despite the significant decreases in MV. Continuous RVM monitoring demonstrates both changes in respiratory patterns and overall adequacy of ventilation, and allows practitioners to quantify the increase in the number and duration apneic episodes as a response to narcotic administration. These case studies demonstrate that a non-invasive respiratory volume monitoring system can detect and quantify respiratory disturbances that currently go undetected.