Patients at High Risk for Obstructive Sleep Apnea Are at Increased Risk for Atrial Fibrillation After Cardiac Surgery: A Cohort Analysis

Positive Airway Pressure in Surgical Patients with Sleep Apnea: What is the Supporting Evidence?

Obstructive sleep apnea (OSA) is prevalent amongst surgical patients and associated with an increased incidence of perioperative complications. The gold standard treatment for moderate-to-severe OSA is positive airway pressure (PAP) therapy. Practice guidelines by the American Society of Anesthesiologists and the Society of Anesthesia and Sleep Medicine have recommended preoperative screening for OSA and consideration of initiation of PAP therapy for patients with severe OSA. These guidelines, developed mainly by the consensus of experts, highlight the adverse impact of OSA on postoperative outcomes and recommend the use of postoperative PAP in surgical patients with moderate to severe OSA. Since the development of these guidelines, there has been an increase in the number of publications regarding the efficacy of PAP therapy in surgical patients with OSA. Our review provides an update on the existing literature on the efficacy of PAP therapy in surgical patients with OSA. We focus on the postoperative complications associated with OSA, potential mechanisms leading to the increased risk of postoperative adverse events, and summarize the perioperative guidelines for the management of patients with OSA, evidence supporting perioperative PAP therapy, as well as limitations to PAP therapy and alternatives. An update on the existing literature of the efficacy of PAP therapy in surgical patients with OSA is critical to assess the impact of prior guidelines, determine when and how to effectively implement PAP therapy, and target barriers to PAP adherence in the perioperative setting.

Sleep-Disordered Breathing, Advanced Age, and Diabetes Mellitus Are Associated with De Novo Atrial Fibrillation after Cardiac Surgery

Background: Postoperative de novo atrial fibrillation (POAF) is one of the most frequently encountered complications following cardiac surgery. Despite the identification of several risk factors, the link between sleep-disordered breathing (SDB) and POAF has barely been examined. The objective of this prospective observational study was to determine whether severe SDB is associated with POAF in patients after elective coronary artery bypass grafting (CABG) surgery. Study design and methods: The incidence and preoperative predictors of in-hospital POAF were assessed in 272 patients undergoing CABG surgery at the University Medical Center Regensburg (Germany). In-hospital POAF was detected by continuous telemetry-ECG monitoring and 12-lead resting ECGs within the first seven postoperative days. POAF that occurred after hospital discharge within 60 days post CABG surgery was classified as post-hospital POAF and was ascertained by standardized phone interviews together with the patients' medical files, including routinely performed Holter-ECG monitoring at 60 days post CABG surgery. The night before surgery, portable SDB monitoring was used to assess the presence and type of severe SDB, defined by an apnea-hypopnea index ≥ 30/h. Results: The incidence of in-hospital POAF was significantly higher in patients with severe SDB compared to those without severe SDB (30% vs. 15%, p = 0.009). Patients with severe SDB suffered significantly more often from POAF at 60 days post CABG surgery compared to patients without severe SDB (14% vs. 5%, p = 0.042). Multivariable logistic regression analysis showed that severe SDB (odds ratio, OR [95% confidence interval, CI]: 2.23 [1.08; 4.61], p = 0.030), age ≥ 65 years (2.17 [1.04; 4.53], p = 0.038), and diabetes mellitus (2.27 [1.15; 4.48], p = 0.018) were significantly associated with in-hospital POAF. After additional adjustment for heart failure, the association between sleep apnea and postoperative atrial fibrillation was attenuated (1.99 [0.92; 4.31], p = 0.081). Conclusions: Amongst established risk factors, severe SDB was significantly associated with in-hospital POAF in patients undergoing CABG surgery. Whether SDB contributes to POAF independently of heart failure and whether risk for POAF may be alleviated by proper treatment of SDB merits further investigation.

Investigate the relationship between obstructive sleep apnea and cardiac arrhythmia after CABG surgery

BACKGROUND AND OBJECTIVE

Heart rhythm disorder is one of the most common problems after coronary artery bypass graft surgery. Various factors, such as the history of sleep apnoea before the operation, may aggravate the occurrence of this disorder. The present study was conducted to determine the relationship between sleep apnoea before surgery and heart rhythm disorder after surgery in patients undergoing coronary Artery Bypass Grafting in 2019.

METHODS

This analytical cross-sectional study was conducted on 192 patients who were selected by sequential sampling. The research tool included demographic information, a checklist of heart rhythm disorders, and the Berlin sleep apnoea questionnaire. Descriptive statistics and the Chi-square test, Fisher's exact test, Mann-Whitney's U-test, and logistic regression were used to analyze the data.

RESULTS

A total of 71.35% of the samples were male, and the mean age of the participants was 57.8 ± 7.5 years. Also, 46.0% of the samples had sleep pane and 21.35% had rhythm disorder. The most frequent heart rhythm disorder in patients with obstructive sleep apnoea was atrial fibrillation. There was a significant relationship between the occurrence of rhythm disorder and a history of smoking (P = 0.021), and the regression model showed that a history of smoking is the only variable related to the occurrence of rhythm disorder after coronary Artery Bypass Grafting (P = 0.005, CI 95%: 6.566-1.386, OR = 3.017).

CONCLUSIONS

The results showed that there is no statistically significant relationship between sleep apnea and rhythm disorder after coronary artery bypass surgery.

Association between obstructive sleep apnea and atrial fibrillation and delirium after cardiac surgery. Sub-analysis of DECADE trial

BACKGROUND

Atrial fibrillation and delirium are common complications after cardiac surgery. Both are associated with increased Intensive Care Unit (ICU) and hospital length of stay, functional decline, 30-day mortality and increase in health care costs. Obstructive Sleep Apnea (OSA) induces deleterious effects in the cardiovascular and nervous systems. We hypothesized that adult patients with preoperative OSA have a higher incidence of postoperative atrial fibrillation and delirium than patients without OSA, after cardiac surgery.

METHODS

Sub-analysis of the DECADE trial at Cleveland Clinic hospitals. Our exposure was OSA, defined by STOP-BANG questionnaire score higher than 5 and/or a preoperative diagnosis of OSA. The primary outcome was atrial fibrillation, defined by clinician diagnosis or documented arrhythmia. The secondary outcome was delirium assessed twice during the initial five postoperative days using the Confusion Assessment Method for ICU. We assessed the association between OSA, and atrial fibrillation and delirium using a logistic regression model adjusted for confounders using inverse probability of treatment weighting.

RESULTS

590 patients were included in the final analysis. 133 were diagnosed with OSA and 457 had no OSA. Satisfactory balance between groups for most confounders (absolute standardized difference < 0.10) was achieved after weighting. The atrial fibrillation incidence was 37% (n = 49) in the patients with OSA and 33% (n = 150) in the non-OSA patients. OSA was not associated with atrial fibrillation with an estimated odds ratio of 1.22 (95% CI: 0.75,1.99;p = 0.416). The delirium incidence was 17% (n = 22) in patients with OSA and 15% (n = 67) in the non-OSA patients. OSA was not associated with delirium with an estimated odds ratio of 0.93 (95% CI: 0.51,1.69;p = 0.800).

CONCLUSION

In adult patients having cardiac surgery, OSA is not associated with a higher incidence of postoperative atrial fibrillation and delirium. These results suggest different prominent factors rather than OSA affect the incidence of these postoperative outcomes.

Impact of sleep disordered breathing on postoperative atrial fibrillation in patients who underwent cardiac surgery: a meta-analysis

Objective: An increasing number of studies suggest that sleep disordered breathing (SDB) may be associated with postoperative atrial fibrillation (POAF), but these studies present discrepant results. Thus, this meta-analysis aimed to synthesize the data associating SDB with POAF in patients who underwent cardiac surgery.Methods: A literature search was performed in the Scopus, PubMed, Web of Science, EMBASE, CENTRAL, Weipu, Wanfang Data, and China National Knowledge Infrastructure databases before August 2022. Data were extracted, and the strength of the relationship between SDB and the risk of POAF was evaluated using odds ratio (OR) and 95% confidence intervals (CIs). All statistical analysis was carried out using the Stata 12.0 software.Results: A total of 24 studies with 660,685 subjects were included in current meta-analysis. SDB was significantly associated with the risk of POAF in the patients who underwent cardiac surgery (OR = 1.49; 95% CI, 1.30-1.70; p < .001). Next subgroup analysis revealed that such association may be increased in the group with medical equipment-measured SDB (OR = 2.27; 95% CI, 1.59-3.23; p < .001), prospective studies (OR = 2.17; 95% CI, 1.55-3.03; p < .001), patients without a previous history of atrial fibrillation (OR = 2.04; 95% CI, 1.47-2.82; p < .001), and patients who received a coronary artery bypass graft (OR = 2.10; 95% CI, 1.45-3.05; p < .001). No publication bias was identified.Conclusion: The results of meta-analysis support that SDB may be associated with an increased risk of POAF in patients who had undergone cardiac surgery, and these results should be confirmed in more rigorously designed studies.KEY MESSAGESPatients with SDB who underwent cardiac surgery showed increased risk of POAF.The relationship between SDB and POAF should be explained with caution with the consideration of various covariate.The effect of pre-treatment of SDB on POAF should be examined in future.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

TRIAL REGISTRATION

PROSPERO registration  CRD42021260451 .

Prehabilitation of Cardiac Surgical Patients, Part 1: Anemia, Diabetes Mellitus, Obesity, Sleep Apnea, and Cardiac Rehabilitation

The concept of "prehabilitation" consists of screening for and identification of pre-existing disorders followed by medical optimization. This is performed for many types of surgery, but may have profound impacts on outcomes particularly in cardiac surgery given the multiple comorbidities typically carried by these patients. Components of prehabilitation include direct medical intervention by preoperative specialists as well as significant care coordination and shared decision making. In this two-part review, the authors describe existing evidence to support the optimization of various preoperative problems and present a few institutional protocols utilized by our center for cardiac presurgical care. This first installment will focus on the management of anemia, obesity, sleep apnea, diabetes, and cardiac rehabilitation prior to surgery. The second will focus on frailty, malnutrition, respiratory disease, alcohol and smoking cessation, and depression.

Perioperative considerations for adult patients with obstructive sleep apnea

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

Causal Effect of Obstructive Sleep Apnea on Atrial Fibrillation: A Mendelian Randomization Study

Background

Obstructive sleep apnea (OSA) has shown to be associated with an increased risk of atrial fibrillation in observational studies. Whether this association reflect causal effect is still unclear. The aim of this study was to evaluate the causal effect of OSA on atrial fibrillation.

Methods and Results

We used a 2‐sample Mendelian randomization (MR) method to evaluate the causal effect of OSA on atrial fibrillation. Summary data on genetic variant‐OSA association were obtained from a recently published genome‐wide association studies with up to 217 955 individuals and data on variant‐atrial fibrillation association from another genome‐wide association study with up to 1 030 836 individuals. Effect estimates were evaluated using inverse‐variance weighted method. Other MR analyses, including penalized inverse‐variance weighted, penalized robust inverse‐variance weighted, MR‐Egger, simple median, weighted median, weighted mode‐based estimate and Mendelian Randomization Pleiotropy Residual Sum and Outlier methods were performed in sensitivity analyses. The MR analyses in both the fixed‐effect and random‐effect inverse‐variance weighted models showed that genetically predicted OSA was associated with an increased risk of atrial fibrillation (odds ratio [OR], 1.21; 95% CI, 1.12–1.31, P<0.001; OR, 1.21; 95% CI, 1.11–1.32, P<0.001) using 5 single nucleotide polymorphisms as the instruments. MR‐Egger indicated no evidence of genetic pleiotropy (intercept, −0.014; 95% CI, −0.033 to 0.005, P=0.14). Results were robust using other MR methods in sensitivity analyses.

Conclusions

This MR analysis found that genetically predicted OSA had causal effect on an increased risk of atrial fibrillation.

Diagnostic accuracy and suitability of instruments that screen for obstructive sleep apnoea, insomnia and sleep quality in cardiac patients: a meta-analysis

BACKGROUND

A number of clinical guidelines recommend that all cardiac rehabilitation patients should be screened for potential sleep disorders with a validated screening instrument. There is currently no consensus on what specific tools should be used.

OBJECTIVE

To identify tools that are practical to use in the clinical environment and have high diagnostic accuracy.

METHODS

We systematically searched online databases to identify patient reported outcome instruments that have been used in published research studies to assess the likelihood of obstructive sleep apnoea (OSA) in cardiac patients. In studies that provided diagnostic data, these data were extracted and verified via an evidence-based diagnostic calculator. Where sufficient numbers of studies were available, a meta-analysis was conducted to determine pooled estimates of specificity, sensitivity and diagnostic odds ratios. Selected papers were qualitatively assessed using the Standards for Reporting Diagnostic accuracy studies (STARD).

RESULTS

Of the 21 instruments identified, six detected likelihood of OSA, two assessed daytime sleepiness, five assessed insomnia and eight examined sleep quality. A meta-analysis of 14 studies that assessed diagnostic accuracy of moderate OSA, revealed moderate sensitivity for the Berlin Questionnaire, Sens = 0.49 (95% CI 0.45-0.52) and good sensitivity for the Stop-BANG, Sens = 0.93 (95% CI 0.87-0.96) but poor specificity at standard cut-off criteria.

CONCLUSION

There are promising practical tools available to screen patients with OSA and other sleep disorders in cardiac rehabilitation settings, but specificity could be improved. Additional assessment of sleep quality may enhance prognostic ability with both OSA and insomnia screening.

Postoperative Outcomes of Patients With Obstructive Sleep Apnea Undergoing Cardiac Surgery

BACKGROUND

Obstructive sleep apnea (OSA) is associated with increased risk of postoperative complications in noncardiac surgery, with limited literature on cardiac surgical patients. Perioperative outcomes of patients with OSA were compared with outcomes of those without OSA undergoing cardiac surgery.

METHODS

This was a retrospective single-center cohort study of adults who underwent cardiac surgery from January 2010 to April 2017. Outcomes of patients with OSA were compared with those without OSA, including length of stay, readmissions, hospital death, and short-term outcomes.

RESULTS

OSA was present in 2636 of 8612 patients (30.6%) identified during the study period with OSA. Patients with OSA had a longer median length of stay (6 vs 5 days, P < .001), longer incidence of prolonged (>7 days) length of stay (26.3% vs 23.0%, P < .001), and were less likely to be discharged to home (78.2% vs 84.4%, P < .001). OSA patients also had a higher 30-day readmission rate (14.7% vs 10.4%, P < .001). Acute kidney injury was more common in OSA patients (25.2% vs 19.9%, P < .001). Our multivariable model found postoperative atrial fibrillation was associated with older age and not OSA status (age <50 years compared with >75 years; odds ratio, 4.10; 95% confidence interval, 3.39-4.96).

CONCLUSIONS

OSA patients had a longer mean length of stay, were more likely to have a prolonged length of stay, more likely to be discharged to a location other than home, and had a higher 30-day readmission rate. This suggests higher resource utilization is required to care for OSA patients after cardiac surgery.

Uncovering Synergistic Mechanism of Chinese Herbal Medicine in the Treatment of Atrial Fibrillation with Obstructive Sleep Apnea Hypopnea Syndrome by Network Pharmacology

Paroxysmal atrial fibrillation (AF) combined with obstructive sleep apnea hypopnea syndrome (OSAHS) is very common in clinical practice. Traditional Chinese medicine (TCM) rule of regulating the liver based on psycho-cardiology shows satisfactory effectiveness in the treatment of paroxysmal AF combined with OSAHS. However, its underlying pharmacological mechanism has not yet been elucidated. This study applied network pharmacology to identify 94 active components in the six TCM liver-regulating herbs and 182 corresponding targets from several databases and comprehensive literature studies, as well as retrieved AF combined with OSAHS-related targets. Cytoscape software was adopted to construct the component-component target network and component-putative target-AF combined with OSAHS target network. Then, we obtained 38 putative therapeutic targets against AF combined with OSAHS. After the production of a putative therapeutic target interaction network, topological analysis was adopted to determine the core targets of TCM liver-regulating herbs in the treatment of paroxysmal AF combined with OSAHS. For all putative therapeutic targets, biological process analysis and pathway enrichment analysis were utilized to investigate the possible mechanism of TCM liver-regulating herbs in the treatment of paroxysmal AF combined with OSAHS. Mechanistically, it included positive regulation of nitric oxide biosynthetic process, aging, response to hypoxia, TNF signaling pathway, HIF-1 signaling pathway, PI3K-Akt signaling pathway, neuroactive ligand-receptor interaction, and calcium signaling pathway. Especially, six core targets of TCM liver-regulating herbs, namely, TNF, STAT3, AKT1, IL-6, TP53, and INS, were significant in the regulation of the above biological processes and pathways. This study demonstrates the multicomponent, multitarget, and multipathway feature of TCM liver-regulating herbs, provides an extensional foundation for further research, and facilitates the reasonable application of TCM liver-regulating herbs in treating paroxysmal AF combined with OSAHS.