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

Sleep Apnea is Not an Obstacle for Outpatient Hip and Knee Arthroplasty

BACKGROUND

Up to 25% of patients requiring hip or knee arthroplasty have sleep apnea (SA), and these patients have historically been excluded from outpatient programs. The objectives of this study were to evaluate same-day discharge failure as well as 30-day complications, readmissions, and unexpected visits.

METHODS

A retrospective case-control study comparing patients who have and do not have SA matched for age, sex and arthroplasty type (total hip arthroplasty, total knee arthroplasty, unicompartimental knee arthroplasty) who underwent primary outpatient surgery between February 2019 and December 2022 in 2 academic hospitals was conducted. Cases with mild SA, moderate SA with a body mass index (BMI) <35, and SA of all severity treated by continuous positive airway pressure machines were eligible. There were 156 patients included (78 cases). Complications were assessed according to the Clavien-Dindo Classification and the Comprehensive Complication Index. Continuous variables were evaluated by Student's T or Mann-Whitney tests, while categorical data were analyzed by Chi-square or Fisher tests. Univariate analyses were performed to determine discharge failure risk factors.

RESULTS

There were 6 cases (7.7%) and 5 controls (6.4%) who failed to be discharged on surgery day (P = .754), with postoperative hypoxemia (6, [3.8%]) and apnea periods (3, [1.9%]) being the most common causes. Higher BMI (odds ratio = 1.19, P = .013) and general anesthesia (odds ratio = 11.97, P = .004) were found to be risk factors for discharge failure. No difference was observed on 30-day readmissions (P = .497), unexpected visits (P = 1.000), and complications on the Clavien-Dindo Classification (P > .269) and Comprehensive Complication Index (P > .334) scales.

CONCLUSIONS

Selected patients who have SA can safely undergo outpatient hip or knee arthroplasty. Higher BMI and general anesthesia increased the odds of same-day discharge failure.

LEVEL OF EVIDENCE

Level III, Case-control Study.

Utility of the psychomotor vigilance task in screening for obstructive sleep apnoea

PURPOSE

The study aimed to assess the performance of the PVT in patients with suspected OSA, evaluate its role in population screening for OSA.

METHODS

The NoSAS, STOP-Bang, ESS scores and PVT tests were performed after suspected OSA patients' admission, followed by PSG. Then we compared the PVT results, calculated the sensitivity, specificity and ROC curve of PVT, and analyzed the accuracy of STOP-Bang and NoSAS questionnaire combined with PVT in predicting OSA.

RESULTS

A total of 308 patients were divided into four groups based on AHI: primary snoring (2.74 ± 1.4 events/h, n = 37); mild OSA (9.96 ± 3.25 events/h, n = 65); moderate OSA (22.41 ± 4.48 events/h, n = 76); and, severe OSA (59.42 ± 18.37 events/h, n = 130). There were significant differences in PVT lapses (p < 0.001) and reaction time (RT, p = 0.03) among the four groups. The PVT lapses and RT were positively correlated with AHI (p < 0.001) and ODI (p < 0.001), and negatively correlated with LSpO2 (p < 0.001). When diagnosing OSA (AHI ≥ 5 events/h), the AUCs of PVT, ESS, STOP-Bang, and NoSAS were 0.679, 0.579, 0.727, and 0.653, respectively; the AUCs of STOP-Bang and NoSAS combined with PVT increased. After combined PVT, the diagnostic specificity of STOP-Bang and NoSAS at nodes with AHI ≥ 5, ≥ 15 and ≥ 30 events/h increased to varying degrees.

CONCLUSION

Patients with OSA exhibited impairment in the PVT, and the combination of the PVT and STOP-Bang or NoSAS scores can improve the diagnostic efficacy and specificity for OSA.

Sex-dependent GOAL screening performance in adults at risk for obstructive sleep apnea

OBJECTIVE

To evaluate possible sex-related differences in the performance of the GOAL, a 4-item obstructive sleep apnea (OSA) screening instrument in adults.

METHODS

Between July 2019 and June 2021, this cross-sectional study included consecutively recruited patients from one Brazilian sleep laboratory undergoing overnight polysomnography. Individuals with GOAL scores ≥ 2 of a maximum of 4 points are classified at high risk for OSA diagnosis. Actual OSA severity was based on the apnea-hypopnea index: ≥ 5.0/h as any OSA, ≥ 15.0/h as moderate-to-severe OSA, and ≥ 30.0/h as severe OSA. Performance of the GOAL instrument in women and men was assessed by the discriminatory ability (obtained from area under the curve [AUC]-Receiver Operating Characteristic curves) and 2×2 contingency tables.

RESULTS

A total of 2,978 subjects (55.3% males) were evaluated. The frequency of GOAL-defined OSA high-risk was statistically higher in men when compared to women (p < 0.001). The GOAL predictive parameters for screening all severity OSA levels were as follows: in females, sensitivity ranging from 58.2% to 78.3% and specificity ranging from 60.0% to 77.6%, while in males, sensitivity ranging from 90.5% to 96.9% and specificity from 20.7% to 46.8%. The GOAL questionnaire had similar discriminatory properties, assessed by AUC, in women and in men: i) any OSA: 0.741 vs. 0.771 (p = 0.204), ii) moderate-to-severe OSA: 0.727 vs. 0.737 (p = 0.595), and iii) severe OSA: 0.728 vs. 0.703 (p = 0.240); respectively.

CONCLUSIONS

The GOAL instrument emerges as a useful tool for screening adult individuals and displays similar performance in both women and men.

Perioperative Care in Cardiac Surgery: A Joint Consensus Statement by the Enhanced Recovery After Surgery (ERAS) Cardiac Society, ERAS International Society, and The Society of Thoracic Surgeons (STS)

Enhanced Recovery After Surgery (ERAS) programs have been shown to lessen surgical insult, promote recovery, and improve postoperative clinical outcomes across a number of specialty operations. A core tenet of ERAS involves the provision of protocolized evidence-based perioperative interventions. Given both the growing enthusiasm for applying ERAS principles to cardiac surgery and the broad scope of relevant interventions, an international, multidisciplinary expert panel was assembled to derive a list of potential program elements, review the literature, and provide a statement regarding clinical practice for each topic area. This article summarizes those consensus statements and their accompanying evidence. These results provide the foundation for best practice for the management of the adult patient undergoing cardiac surgery.

Perioperative management of Obstructive Sleep Apnoea: Present themes and future directions

PURPOSE OF REVIEW

Obstructive sleep apnoea (OSA) is an increasingly common pathology that all those involved in perioperative care will come across. Patients with the condition present a challenge at many stages along the perioperative journey, not least because many patients living with OSA are unaware of their diagnosis.Key interventions can be made pre, intra-, and postoperatively to improve outcomes. Knowledge of screening tools, diagnostic tests, and the raft of treatment options are important for anyone caring for these patients.

RECENT FINDINGS

Recent literature has highlighted the increasing complexity of surgical patients and significant underdiagnosis of OSA in this patient population. Work has demonstrated how and why patients with OSA are at a higher perioperative risk and that effective positive airways pressure (PAP) therapy can reduce these risks, alongside evidencing how best to optimise adherence to therapy, a key issue in OSA.

SUMMARY

OSA, and particularly undiagnosed OSA, presents a huge problem in the perioperative period. Perioperative PAP reduces the risk of postoperative complications but adherence remains an issue. Bespoke perioperative pathways should be developed to identify and optimise high risk patients, although at present evidence on how best to achieve this is lacking.

Sleep study measures on post-operative night one following expansion pharyngoplasty for obstructive sleep apnea

PURPOSE

To examine the changes in measures of sleep apnea severity and hypoxemia on the first post-operative night (PON1) following expansion pharyngoplasty as a means to assess the safety of same day discharge after surgery.

MATERIALS AND METHODS

Prospective cohort study of subjects with moderate-severe obstructive sleep apnea who underwent expansion pharyngoplasty at a single academic sleep surgical practice. A WatchPAT study was performed on the night immediately following surgery (PON1) and comparisons were made to baseline sleep testing.

RESULTS

Twenty subjects who had a mean age of 45.7 ± 10.8 years old and a mean body-mass index (BMI) of 31.4 ± 3.2 kg/m² were enrolled. Patients had baseline severe OSA with mean apnea hypopnea index (AHI) 39.4 ± 19.5/h, O2 nadir 80.8 ± 6.1 % and time with oxygen saturation below 88 % (T88) 12.3 ± 13.2 min. Measures of sleep apnea and nocturnal hypoxemia were not significantly different on PON1. AHI was increased by >20 % in 11 (55.0 %) patients. One patient demonstrated a >10 % worsening in O2 nadir, and 8 patients (45.0 %) demonstrated a >20 % worsening in T88. BMI over 32 was associated with elevated odds of worsening in T88, and anesthesia involving ketamine was associated with lower odds of a 20 % worsening in AHI or T88.

CONCLUSIONS

On PON1 following expansion pharyngoplasty, AHI and nocturnal hypoxemia are stable overall but variable on an individual basis. The decision for admission should therefore be made on a case-by-case basis. Further research is need to elucidate definitive predictors of worsening measures on PON1.

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 .

Reliability of STOP-Bang questionnaire and pulse oximetry as predictors of OSA - a retrospective study

OBJECTIVE

To verify the reliability of a STOP-Bang questionnaire and objective blood oxygen concentration (SpO2) estimation by pulse oximetry as an indicator of patients' vulnerability to OSA, by correlating data of these two tests with that of the "gold standard" all-night polysomnography.

METHODS

STOP-Bang score and pulse oximetry value (SpO2) for each patient were tabulated against the total sleep AHI score (obtained from subsequent all-night polysomnography) and analyzed to evaluate the diagnostic accuracy of the STOP-Bang questionnaire and pulse oximetry.

RESULTS

With sensitivity and specificity scores of 91.2% and 88.6%, respectively, positive predictive value 90.5%, negative predictive value 40.2%, the twin diagnostic test (STOP-Bang and pulse oximetry) was found to be highly congruent with the polysomnography (PSG), achieving a diagnostic accuracy of 85%.

CONCLUSION

Dental chairside screening by STOP-Bang questionnaire and pulse oximetry would be a good option, especially where logistic and economic constraints impede all-night polysomnography.

Biochemical Markers and Obstructive Sleep Apnea Risk in Individuals After Long-Term Bariatric Surgery

BACKGROUND

Individuals who have undergone long-term bariatric surgery may be at increased obstructive sleep apnea (OSA) risk. The purpose of this study was to estimate the frequency of OSA risk and its associations, via biochemical markers, in patients who have undergone long-term bariatric surgery.

METHODS

This cross-sectional study evaluated patients after 5 years or more post Roux-en-Y gastric bypass. Biochemical markers, anthropometrics, and OSA risk, via the STOP-Bang score screening tool, were evaluated. Independent Student t, Pearson's chi-squared, or correlation tests were applied, according to total OSA risk score groups or its isolated components.

RESULTS

Among the 77 patients evaluated (88.3% female; body mass index = 32.7 ± 5.8 kg/ m²; postoperative time = 9.9 ± 3.1 years), 36 were at risk for OSA. OSA risk score was positively correlated to high-sensitivity C-reactive protein levels (r² = 0.270; p = 0.025), triglycerides (r² = 0.338, p = 0.004), total cholesterol (r² = 0,262; p = 0,028), and HbA1c (r² = 0.332; p = 0.005). Compared to each counterpart, basal insulin and triglycerides were higher among those who self-reported witnessed apnea (12.8 ± 6.5 vs 8.1 ± 3.8, p = 0.013; 136.4 ± 41.1 vs 88.5 ± 34.8, p = 0.001, respectively), while levels of total cholesterol and LDL-C were higher in participants who reported tiredness (183.9 ± 27.0 vs 164.8 ± 33.4, p = 0.005; 105.9 ± 24.4 vs 92.0 ± 26.6, p = 0.018). Participants with snoring also had higher levels of triglycerides (107 ± 41.1 vs 83.7 ± 33.9, p = 0.010).

CONCLUSIONS

OSA risk was highly prevalent among patients who had undergone long-term bariatric surgery, as noted via increased STOP-Bang scores, as were isolated components related to inflammatory markers and lipid and glycemic profile.

Use of a urinary catheter as a guidewire to facilitate safe nasotracheal intubation following iatrogenic retropharyngeal perforation

Nasotracheal intubation facilitates adequate access for surgical procedures in the oral cavity, is not limited by mouth opening and can be better tolerated by patients in intensive care. Complications of nasotracheal intubation can include epistaxis, turbinate injury and sinusitis. Retropharyngeal submucosal perforation by the tracheal tube has also been infrequently reported. Here, we report a case of difficult nasotracheal intubation resulting in retropharyngeal submucosal perforation in a patient with a history of obstructive sleep apnoea listed for uvulopalatopharyngoplasty. To facilitate successful tracheal re-intubation, we used a soft urinary catheter via the other nostril. In this report, we discuss the reasons why this complication may have occurred, how submucosal perforation could be avoided, and reflect on our management of this rare complication. Difficult nasotracheal intubation can present unique challenges, and airway management plans should be made accordingly.

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.

Extubation of the potentially difficult airway in the intensive care unit

PURPOSE OF REVIEW

Extubation in the intensive care unit (ICU) is associated with a failure rate requiring reintubation in 10-20% patients further associated with significant morbidity and mortality. This review serves to highlight recent advancements and guidance on approaching extubation for patients at risk for difficult or failed extubation (DFE).

RECENT FINDINGS

Recent literature including closed claim analysis, meta-analyses, and national society guidelines demonstrate that extubation in the ICU remains an at-risk time for patients. Identifiable strategies aimed at optimizing respiratory mechanics, patient comorbidities, and airway protection, as well as preparing an extubation strategy have been described as potential methods to decrease occurrence of DFE.

SUMMARY

Extubation in the ICU remains an elective decision and patients found to be at risk should be further optimized and planning undertaken prior to proceeding. Extubation for the at-risk patient should be operationalized utilizing easily reproducible strategies, with airway experts present to guide decision making and assist in reintubation if needed.

Postoperative outcomes in surgical patients with obstructive sleep apnoea diagnosed by sleep studies: a meta-analysis and trial sequential analysis

Identifying surgical patients with obstructive sleep apnoea may assist with anaesthetic management to minimise postoperative complications. Using trial sequential analysis, we evaluated the impact of obstructive sleep apnoea diagnosed by polysomnography or home sleep apnoea testing on postoperative outcomes in surgical patients. Multiple databases were systematically searched. Outcomes included: total postoperative complications, systemic complications (cardiovascular, respiratory, neurological, renal, infectious) and specific complications (atrial fibrillation, myocardial infarction, combined hospital and intensive care unit re-admission, mortality). The pooled odds ratios of postoperative complications were evaluated by the Mantel-Haenszel method random-effects model. Meta-analysis and meta-regression were conducted, and the GRADE approach was used to evaluate the certainty of evidence. Twenty prospective cohort studies with 3756 patients (2127 obstructive sleep apnoea and 1629 non-obstructive sleep apnoea) were included (9 in non-cardiac surgery and 11 in cardiac surgery). Postoperative complications were almost two-fold higher with obstructive sleep apnoea, OR (95%CI) 1.92 (1.52-2.42), p < 0.001; certainty of evidence, moderate. Obstructive sleep apnoea was associated with a 1.5 times increased risk of postoperative cardiovascular complications, OR (95%CI) 1.56 (1.20-2.02), p = 0.001; certainty of evidence, moderate; an almost two-fold increase in respiratory complications, OR (95%CI) 1.91 (1.39-2.62), p < 0.001; certainty of evidence, moderate; and hospital and ICU re-admission, OR (95%CI) 2.25 (1.21-4.19), p = 0.01; certainty of evidence, low. Trial sequential analysis showed adequate information size for postoperative complications. Baseline confounding factors were adjusted by meta-regression, and the sub-group analysis did not materially change our results. This increased risk occurred especially in patients in whom obstructive sleep apnoea had been newly diagnosed, emphasising the importance of pre-operative screening.

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.

The association between obstructive sleep apnea risk and cognitive disorders: a population-based study

STUDY OBJECTIVES

To examine the association between OSA risk and cognitive disorders among US adults.

METHODS

Data from the 2016 wave of the Health and Retirement Study (HRS) were utilized. Probable OSA cases were identified with survey items that resembled critical elements of a clinically validated OSA screen (STOP-Bang questionnaire). Weighted prevalence of cognitive impairment not dementia (CIND) and dementia among individuals with and without probable OSA were assessed. Cross-sectional analyses of associations between OSA risk and cognitive outcomes, along with effect modification by race and ethnicity, were estimated using imputed data.

RESULTS

Of the 20,910 HRS participants, 60% had probable OSA. CIND and dementia were more common among adults with probable OSA as compared to those without (12.7% vs. 8.0% for CIND; 3.2% vs 2.0% for dementia). Probable OSA was associated with CIND (OR=1.22, 1.08-1.37) and dementia (OR=1.27, 1.04-1.54). Race/ethnicity significantly modified the association between probable OSA and CIND, with a higher risk for CIND in Whites (OR=1.35, 1.17-1.57) as compared to non-Whites (OR=0.98, 0.81-1.19).

CONCLUSIONS

CIND and dementia are more common among older adults who are at high risk for OSA, as compared to low-risk individuals. These data highlight the importance of consideration of OSA risk in large-scale studies of OSA and cognitive disorders.

Sleep Study Measures on Postoperative Night 1 Following Implantation of the Hypoglossal Nerve Stimulator

OBJECTIVE

To examine the changes in measures of sleep apnea severity and hypoxemia on the first postoperative night following implantation of the hypoglossal nerve stimulator.

STUDY DESIGN

This was a single-arm prospective cohort study.

SETTING

A single academic sleep surgical practice.

METHODS

Subjects with moderate to severe obstructive sleep apnea underwent implantation of the hypoglossal nerve stimulator (HGNS) and were discharged to home the same day as surgery. A single-night WatchPAT study was performed on the night immediately following surgery (PON 1) and was compared to baseline sleep testing.

RESULTS

Twenty subjects who were an average of 58.6 ± 2.5 years old, were 25% female, and had a mean body mass index of 28.1 ± 0.9 kg/m² completed the study. Mean O₂ nadir at baseline was 79.6% ± 1.1% compared to 82.7% ± 0.9% (P = .013) on PON 1. One patient demonstrated a >10% worsening in O₂ nadir. Only 2 additional patients demonstrated a worsening in O₂ nadir on PON 1, each by only 1 percentage point. Neither mean time spent below SpO₂ 88% nor oxygen desaturation index (ODI) worsened postoperatively (mean time spent below oxygen saturation of 88%, 27.8 ± 7.85 vs 11.2 ± 5.2, P = .03; mean ODI, 29.6 ± 5.2/h vs 21.0 ± 5.4/h, P = .10). Mean obstructive apnea hypopnea index (AHI) was no worse (40.6 ± 4.7/h to 28.7 ± 4.2/h, P = .02), with only 2 patients experiencing an obstructive AHI >20% more severe than baseline. Only 1 patient demonstrated a clinically meaningful increase in central AHI on PON 1.

CONCLUSIONS

Overall, AHI and measures of nocturnal hypoxemia are stable, if not improved, on PON 1 following HGNS implantation. These findings support the safety of same-day discharge following implantation of the hypoglossal nerve stimulator.

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.

Diagnostic performance of the STOP-Bang questionnaire as a screening tool for obstructive sleep apnea in different ethnic groups

STUDY OBJECTIVES

The STOP-Bang questionnaire is a concise and easy screening tool for obstructive sleep apnea (OSA). Using modified body mass index (BMI), we assessed the diagnostic performance of the STOP-Bang questionnaire in predicting OSA in ethnically different groups of patients undergoing surgery.

METHODS

This was a multicenter prospective cohort study involving patients with cardiovascular risk factors who were undergoing major noncardiac surgery. Patients underwent home sleep apnea testing. All patients completed the STOP-Bang questionnaire. The predictive parameters of STOP-Bang scores were calculated against the apnea-hypopnea index.

RESULTS

From 4 ethnic groups 1,205 patients (666 Chinese, 161 Indian, 195 Malay, and 183 Caucasian) were included in the study. The mean BMI ranged from 25 ± 4 to 30 ± 6 kg/m² and mean age ranged from 64 ± 8 to 71 ± 10 years. For the Chinese and Indian patients, diagnostic parameters are presented using BMI threshold of 27.5 kg/m² with the area under curve to predict moderate-to-severe OSA being 0.709 (0.665-0.753) and 0.722 (0.635-0.808), respectively. For the Malay and Caucasian, diagnostic parameters are presented using BMI threshold of 35 kg/m² with the area under curve for predicting moderate-to-severe OSA being 0.645 (0.572-0.720) and 0.657 (0.578-0.736), respectively. Balancing the sensitivity and specificity, the optimal STOP-Bang thresholds for the Chinese, Indian, Malay, and Caucasian groups were determined to be 4 or greater.

CONCLUSIONS

For predicting moderate-to-severe OSA, we recommend BMI threshold of 27.5 kg/m² for Chinese and Indian patients and 35 kg/m² for Malay and Caucasian patients. The optimal STOP-Bang threshold for the Chinese, Indian, Malay and Caucasian groups is 4 or greater.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Postoperative Vascular Events in Unrecognized Obstructive Sleep Apnea; URL: https://clinicaltrials.gov/ct2/show/study/NCT01494181; Identifier: NCT01494181.

Validity of the STOP-Bang Questionnaire in Identifying OSA in a Dental Patient Cohort

Background and objectives: Obstructive Sleep Apnea represents a widespread problem in the population, but it is often not diagnosed and not considered a true pathology. Different diagnostic tools are available for the diagnosis of sleep apnea. This study aims to demonstrate the ability of the STOP-Bang (Snoring, Tiredness, Observed apnea, high blood Pressure, Body mass index, Age, Neck circumference, and Gender) questionnaire in identifying subjects with Obstructive Sleep Apnea (OSA) Syndrome, highlighting the role of dentists as epidemiological sentinels. Materials and methods: the STOP-Bang questionnaire was administered to a cohort of 1000 patients, assessing three private dental clinics in Italy. Excessive daytime sleepiness was measured using Epworth Sleepiness Scale (ESS) and defined as ≥ 10. Subjects were considered at risk of OSA if they had three or more positive items at STOP-Bang and were invited to undergo further examination with a type 3 polygraph. Presence of OSA was measured with the apnea-hypopnea index (AHI) and defined as AHI ≥ 5. Results: 482/1000 subjects (48.2%) had three or more positive items in the STOP-Bang questionnaire and were considered at risk for Obstructive Sleep Apnea Syndrome (OSAS). Excessive daytime sleepiness (EDS ≥ 10) was more frequent among subjects at risk for OSAS (73/482, 15.1%) vs. those not at risk for OSAS (30/518, 5.8%) (p < 0.0001). Moreover, 153/482 subjects at risk for OSAS (31.7%) accepted further examination with a type 3 polygraph. Presence of OSAS (AHI ≥ 5) was suggested in 121/153 subjects (79.1%, 95% CI 71.6% to 85.1%), with 76/121 subjects (62.8%) needing treatment (AHI ≥ 15). Conclusion: the high prevalence of OSAS highlights the role of dentists as “epidemiological sentinels”. The STOP-Bang questionnaire is a simple and efficacious instrument for screening sleep apnea patients.

Cost-effectiveness Analysis of Preoperative Screening Strategies for Obstructive Sleep Apnea among Patients Undergoing Elective Inpatient Surgery

Background

Obstructive sleep apnea is underdiagnosed in surgical patients. The cost-effectiveness of obstructive sleep apnea screening is unknown. This study’s objective was to evaluate the cost-effectiveness of preoperative obstructive sleep apnea screening (1) perioperatively and (2) including patients’ remaining lifespans.

Methods

An individual-level Markov model was constructed to simulate the perioperative period and lifespan of patients undergoing inpatient elective surgery. Costs (2016 Canadian dollars) were calculated from the hospital perspective in a single-payer health system. Remaining model parameters were derived from a structured literature search. Candidate strategies included: (1) no screening; (2) STOP-Bang questionnaire alone; (3) STOP-Bang followed by polysomnography (STOP-Bang + polysomnography); and (4) STOP-Bang followed by portable monitor (STOP-Bang + portable monitor). Screen-positive patients (based on STOP-Bang cutoff of at least 3) received postoperative treatment modifications and expedited definitive testing. Effectiveness was expressed as quality-adjusted life month in the perioperative analyses and quality-adjusted life years in the lifetime analyses. The primary outcome was the incremental cost-effectiveness ratio.

Results

In perioperative and lifetime analyses, no screening was least costly and least effective. STOP-Bang + polysomnography was the most effective strategy and was more cost-effective than both STOP-Bang + portable monitor and STOP-Bang alone in both analyses. In perioperative analyses, STOP-Bang + polysomnography was not cost-effective compared to no screening at the $4,167/quality-adjusted life month threshold (incremental cost-effectiveness ratio $52,888/quality-adjusted life month). No screening was favored in more than 90% of iterations in probabilistic sensitivity analyses. In contrast, in lifetime analyses, STOP-Bang + polysomnography was favored compared to no screening at the $50,000/quality-adjusted life year threshold (incremental cost-effectiveness ratio $2,044/quality-adjusted life year). STOP-Bang + polysomnography was favored in most iterations at thresholds above $2,000/quality-adjusted life year in probabilistic sensitivity analyses.

Conclusions

The cost-effectiveness of preoperative obstructive sleep apnea screening differs depending on time horizon. Preoperative screening with STOP-Bang followed by immediate confirmatory testing with polysomnography is cost-effective on the lifetime horizon but not the perioperative horizon. The integration of preoperative screening based on STOP-Bang and polysomnography is a cost-effective means of mitigating the long-term disease burden of obstructive sleep apnea.

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Validation of the Spanish Version of the STOP-Bang Questionnaire: Usefulness as a Screening Tool for Obstructive Sleep Apnea in Adults

OBJECTIVES

Obstructive sleep apnea syndrome (OSAS) is an increasing health problem, the diagnosis of which is generally delayed due to long waiting lists for the tests used to identify it. Therefore, tools that help on classifying patients at higher risk of suffering this syndrome have been developed.

METHODS

One hundred ninety-three consecutive patients, with and without OSAS, filled in the Spanish version of the STOP-Bang questionnaire in Hospital Universitario de Torrejón (Spain). Polysomnographies were performed to diagnose the presence and severity of the OSAS. Statistics analysis of the demographic characteristics of the sample and the questionnaire results was performed.

RESULTS

Most patients were male (73%) and the mean age was 50.4 years (ranging from 19-77 years). Cronbach α coefficient in the sample was 0.8072. A statistically significant difference was noted in the questionnaire scores between patients with OSAS and those without the syndrome.

CONCLUSIONS

The Spanish version of the STOP-Bang questionnaire possess a good internal consistency that allows us to rely on it as a screening tool for patients with OSAS. In our sample, a difference in the questionnaire score was appreciated between patients with and without the syndrome, which strongly supports the utility of the questionnaire for its purpose.

Driving with undiagnosed obstructive sleep apnea (OSA): High prevalence of OSA risk in drivers who experienced a motor vehicle crash

Objective: Obstructive sleep apnea (OSA) is a risk factor for motor vehicle crashes (MVC), and patients with diagnosed OSA have a higher likelihood of being involved in a traffic accident. OSA, however, is often underdiagnosed in the general population. The purpose of this study was to assess the risk of undiagnosed OSA among hospitalized patients involved in MVCs.Methods: This is a prospective, observational pilot study of adult trauma patients admitted to a Level 1 trauma center after being the driver in a MVC. Patients were administered the STOP-Bang to assess risk of OSA and were asked questions about the circumstances of the MVC. Patients with a STOP-Bang score 5-8 were considered to be at high risk for OSA. Differences between variables were assessed using independent t-tests and chi-square.Results: Eighty patients participated in the study, and 26% (n = 21) were considered to be at high risk for OSA based on the STOP-Bang score. Compared to patients at low and intermediate risk, patients at high risk for OSA were significantly older (p < .001), had longer hospitalization (p = .06), and were less likely to discharge home from the hospital (p = .01). Patients at moderate and high risk had higher rates of hospital readmission within 1 year of discharge, when compared to the low risk group. Eighty-four percent of all crashes involved a single occupant (driver) in the vehicle, 58% involved only a single vehicle, and 40% occurred on a rural road. There were no significant differences between risk groups for number of vehicles involved in the accident, location of the accident, or number of vehicle occupants.Conclusions: Results of this pilot study suggest that more than one-quarter of drivers hospitalized after motor vehicle crashes were at high risk for OSA. Diagnosed or undiagnosed OSA is a significant public health concern and an established risk factor for motor vehicle accidents. Standardized screening for risk of sleep apnea should be considered by primary care physicians when guiding patients on health and behavior decisions, particularly in regards to driving and road safety.

Obstructive Sleep Apnea Screening with a 4-Item Instrument, Named GOAL Questionnaire: Development, Validation and Comparative Study with No-Apnea, STOP-Bang, and NoSAS

BACKGROUND

Obstructive sleep apnea (OSA) is a very prevalent disorder. Here, we aimed to develop and validate a practical questionnaire with yes-or-no answers, and to compare its performance with other well-validated instruments: No-Apnea, STOP-Bang, and NoSAS.

METHODS

A cross-sectional study containing consecutively selected sleep-lab subjects underwent full polysomnography. A 4-item model, named GOAL questionnaire (gender, obesity, age, and loud snoring), was developed and subsequently validated, with item-scoring of 0-4 points (≥2 points indicating high risk for OSA). Discrimination was assessed by area under the curve (AUC), while predictive parameters were calculated using contingency tables. OSA severity was classified based on conventionally accepted apnea/hypopnea index thresholds: ≥5.0/h (OSA_≥5), ≥15.0/h (OSA_≥15), and ≥30.0/h (OSA_≥30).

RESULTS

Overall, 7377 adults were grouped into two large and independent cohorts: derivation (n = 3771) and validation (n = 3606). In the derivation cohort, screening of OSA_≥5, OSA_≥15, and OSA_≥30 revealed that GOAL questionnaire achieved sensitivity ranging from 83.3% to 94.0% and specificity ranging from 62.4% to 38.5%. In the validation cohort, screening of OSA_≥5, OSA_≥15, and OSA_≥30, corroborated validation steps with sensitivity ranging from 83.7% to 94.2% and specificity from 63.4% to 37.7%. In both cohorts, discriminatory ability of GOAL questionnaire for screening of OSA_≥5, OSA_≥15, and OSA_≥30 was similar to No-Apnea, STOP-Bang or NoSAS.

CONCLUSION

All four instruments had similar performance, leading to a possible greater practical implementation of the GOAL questionnaire, a simple instrument with only four parameters easily obtained during clinical evaluation.

Prevalence of risk for sleep apnea among hospitalized patients who survived a medical emergency team activation

STUDY OBJECTIVES

Sleep-disordered breathing (SDB) is a common disorder that causes people to stop breathing in their sleep, and obstructive sleep apnea (OSA) is the most common form of SDB in the general population. Because OSA is often undiagnosed and undermanaged, it has been associated with adverse events and morbidity in hospitalized patients. The purpose of the study was to evaluate prevalence of OSA risk in a population of patients who survived a medical emergency team (MET) activation during hospitalization.

METHODS

This prospective study was conducted at a hospital in the Midwest in 2014. Patients who survived a MET activation and consented to participate were administered the STOP-Bang questionnaire and asked other health and lifestyle questions. Review of the medical record was conducted to ascertain patient characteristics, comorbidities, and medications. Differences were assessed using Kruskal-Wallis one-way analysis of variance and the chi-square test.

RESULTS

Of 148 study patients, median age was 68 years (interquartile range: 55-78) and 15% were morbidly obese (body mass index ≥ 40 kg/m²). Fifty percent of patients (n = 74) were found to be at high risk for OSA, yet only 38% (n = 28) of those patients received a previous diagnosis of OSA. Variables available in the medical record were highly correlated with the overall STOP-Bang score (r =. 75, P < .001).

CONCLUSIONS

Half of patients who survived a MET activation during hospitalization screened at high risk for OSA. Standardized screening for risk of sleep apnea, as well as a truncated risk score generated by variables in the medical record, could guide clinical decision making in this at-risk population.

Undiagnosed Obstructive Sleep Apnea as Predictor of 90-Day Readmission for Brain Tumor Patients

BACKGROUND

Previously undiagnosed obstructive sleep apnea (OSA) is a known contributor to negative postoperative outcomes. The STOP-Bang questionnaire is a screening tool for OSA that has been validated in both medical and surgical populations. The authors have previously studied this screening tool in a brain tumor population at 30 days. The present study seeks to investigate the effectiveness of this questionnaire, for predicting 90-day readmissions in a population of brain tumor patients with previously undiagnosed OSA.

METHODS

Included for analysis were all patients undergoing craniotomy for supratentorial neoplasm at a multihospital, single academic medical center. Data were collected from supratentorial craniotomy cases for which the patient was alive at 90 days after surgery (n = 238). Simple logistic regression analyses were used to assess the ability of the STOP-Bang questionnaire and subsequent single variables to accurately predict patient outcomes at 90 days.

RESULTS

The sample included 238 brain tumor admissions, of which 50% were female (n = 119). The average STOP-Bang score was 1.95 ± 1.24 (range 0-7). A 1-unit higher increase in STOP-Bang score accurately predicted 90-day readmissions (odds ratio [OR] = 1.65, P = 0.001), 30- to 90-day emergency department visits (OR = 1.85, P < 0.001), and 30- to 90-day reoperation (OR = 2.32, P < 0.001) with fair accuracy as confirmed by the receiver operating characteristic (C-statistic = 0.65-0.76). However, the STOP-Bang questionnaire did not correlate with home discharge (P = 0.315).

CONCLUSIONS

The results of this study suggest that undiagnosed OSA, as evaluated by the STOP-Bang questionnaire, is an effective predictor of readmission risk and health system utilization in a brain tumor craniotomy population with previously undiagnosed OSA.

The relationship between obstructive sleep apnoea and postoperative delirium and pain: an observational study of a surgical cohort

Patients with obstructive sleep apnoea are at increased risk of adverse postoperative outcomes, such as cardiac and respiratory complications. It has been hypothesised that obstructive sleep apnoea also increases the risk for postoperative delirium and acute postoperative pain. We conducted a retrospective, observational study investigating the relationship of obstructive sleep apnoea with postoperative delirium and acute postoperative pain severity. Patients were classified as being at high risk for obstructive sleep apnoea if they had been diagnosed with this condition, or if they were positive for more than four factors using the 'STOP-BANG' screening tool. Adjusted logistic regression was used to investigate the association between obstructive sleep apnoea and postoperative delirium, and multivariable linear regression to study the relationship between obstructive sleep apnoea and postoperative pain severity. The incidence of postoperative delirium was 307 in 1441 patients (21.3%; 95%CI 19.2-23.5%). In unadjusted analysis, high risk for obstructive sleep apnoea was associated with delirium, with an odds ratio (95%CI) of 1.77 (1.22-2.57; p = 0.003). After adjustment for pre-specified variables, the association was not statistically significant with odds ratio 1.34 (0.80-2.23; p = 0.27). The mean (SD) maximum pain (resting or provoked) reported for the entire cohort was 63.8 (27.9) mm on a 0-100 mm visual analogue scale. High risk for obstructive sleep apnoea was not associated with postoperative pain severity (β-coefficient 2.82; 95%CI, -2.34-7.97; p = 0.28). These findings suggest that obstructive sleep apnoea is unlikely to be a strong risk factor for postoperative delirium or acute postoperative pain severity.

The importance of the STOP- BANG questionnaire as a preoperative assessment tool for the elderly population

Undiagnosed obstructive sleep apnea (OSA) may adversely impact surgical patients and can lead to increased morbidity and mortality during the perioperative period, especially among the geriatric patient population (Chung et al. 2008, 2012, 2014; McDonald et al., 2018; Zietlow et al., 2018; Singh et al., 2012). The setting of this quality improvement project was a preoperative anesthesia and geriatric evaluation clinic housed within a 957-bed tertiary academic affiliated hospital. The sample included 45 patients who met the criteria established for surgery and OSA screening preoperatively. Nine patients (20.0%) were assessed as low risk (Stop-bang [SB] score </=2) for OSA, and 36 patients (80.0%) had a prior diagnosis from an ICD-9/10 code or a SB score >/= 3 indicative of high-risk for OSA. The retrospective utilization of a modified SB screening on charts that did not receive a clinical OSA evaluation (n = 52) detected 23 (44.2%) patients who were considered high-risk for OSA but were not identified prior to surgery. The SB questionnaire is underutilized, and patients' OSA is often unidentified prior to surgery.

Atelectasis in Bariatric Surgery: Review Analysis and Key Practical Recommendations

Obesity is a condition that affects multiple organ systems, particularly the cardiovascular and respiratory system. In recent years, bariatric surgery has been reported to be the gold standard in the treatment of morbid obesity. Body mass index alone is insufficient to predict risks related to anaesthesia and surgery. Obesity contributes to significant postoperative atelectasis and is considered an independent risk factor for postoperative atelectasis owing to decreased functional residual capacity. The treatment and reversibility of atelectasis developed in obese patients undergoing bariatric surgery are challenging. Therefore, an optimisation of pulmonary functions before surgery, lung-sparing ventilation during the perioperative period, awareness of potential postoperative complications and knowledge about preventive measures and therapeutic approaches have become increasingly important in bariatric surgery. The aim of this review was to aid clinicians in the management of atelectasis in patients undergoing bariatric surgery during the perioperative and postoperative period.

Undiagnosed obstructive sleep apnea as a predictor of 30-day readmission for brain tumor patients

OBJECTIVE

Obstructive sleep apnea (OSA) is known to be associated with negative outcomes and is underdiagnosed. The STOP-Bang questionnaire is a screening tool for OSA that has been validated in both medical and surgical populations. Given that readmission after surgical intervention is an undesirable event, the authors sought to investigate, among patients not previously diagnosed with OSA, the capacity of the STOP-Bang questionnaire to predict 30-day readmissions following craniotomy for a supratentorial neoplasm.

METHODS

For patients undergoing craniotomy for treatment of a supratentorial neoplasm within a multiple-hospital academic medical center, data were captured in a prospective manner via the Neurosurgery Quality Improvement Initiative (NQII) EpiLog tool. Data were collected over a 1-year period for all supratentorial craniotomy cases. An additional criterion for study inclusion was that the patient was alive at 30 postoperative days. Statistical analysis consisted of simple logistic regression, which assessed the ability of the STOP-Bang questionnaire and additional variables to effectively predict outcomes such as 30-day readmission, 30-day emergency department (ED) visit, and 30-day reoperation. The C-statistic was used to represent the receiver operating characteristic (ROC) curve, which analyzes the discrimination of a variable or model.

RESULTS

Included in the sample were all admissions for supratentorial neoplasms treated with craniotomy (352 patients), 49.72% (n = 175) of which were female. The average STOP-Bang score was 1.91 ± 1.22 (range 0-7). A 1-unit higher STOP-Bang score accurately predicted 30-day readmissions (OR 1.31, p = 0.017) and 30-day ED visits (OR 1.36, p = 0.016) with fair accuracy as confirmed by the ROC curve (C-statistic 0.60-0.61). The STOP-Bang questionnaire did not correlate with 30-day reoperation (p = 0.805) or home discharge (p = 0.315).

CONCLUSIONS

The results of this study suggest that undiagnosed OSA, as assessed via the STOP-Bang questionnaire, is a significant predictor of patient health status and readmission risk in the brain tumor craniotomy population. Further investigations should be undertaken to apply this prediction tool in order to enhance postoperative patient care to reduce the need for unplanned readmissions.

Perioperative considerations and anesthesia management in patients with obstructive sleep apnea undergoing ophthalmic surgery

Obstructive sleep apnea (OSA) is a disorder characterized by breathing cessation caused by obstruction of the upper airway during sleep. It is associated with multiorgan comorbidities such as obesity, hypertension, heart failure, arrhythmias, diabetes mellitus, and stroke. Patients with OSA have an increased prevalence of ophthalmic disorders such as cataract, glaucoma, central serous retinopathy (detachment of retina, macular hole), eyelid laxity, keratoconus, and nonarteritic anterior ischemic optic neuropathy; and some might require surgery. Given that OSA is associated with a high incidence of perioperative complications and more than 80% of surgical patients with OSA are unrecognized, all surgical patients should be screened for OSA (eg, STOP-Bang questionnaire) with comorbidities identified. Patients suspected or diagnosed with OSA scheduled for ophthalmic surgery should have their comorbid conditions optimized. This article includes a review of the literature and highlights best perioperative anesthesia practices in the management of ophthalmic surgical patients with OSA.

Obstructive sleep apnea affects complication rates following knee arthroscopy but use of continuous positive airway pressure is not protective against complications

PURPOSE

Obstructive sleep apnea (OSA) has not been studied as a risk factor for complications following knee arthroscopy. The goals of this study were to: (1) compare complication rates after knee arthroscopy between patients with and without OSA and (2) evaluate whether continuous positive airway pressure (CPAP) mitigated complication rates.

METHODS

A national private insurance database was queried for patients undergoing simple knee arthroscopy from 2007 to 2016. Patients with a diagnosis of OSA were then identified using ICD-9/10 codes. Patients with OSA were then subdivided into cohorts with and without a billing code for a CPAP device. Adverse events within 30 days postoperatively related to OSA were then assessed in all groups: (1) emergency room (ER) visit, (2) hospital admission, (3) pulmonary embolism (PE), (4) myocardial infarction, (5) respiratory arrest and (6) in-hospital mortality within 6 months postoperatively. Adverse event rates were compared between the control and study groups using a multivariable regression analysis.

RESULTS

97,036 patients underwent simple knee arthroscopy with 8656 patients having a diagnosis of OSA. Of these, 3820 (44%) had orders for CPAP machines. After controlling for confounders, patients with OSA had significantly higher risk of ER visits, PE and respiratory arrest compared to controls (p < 0.05). The majority of these significant findings persisted regardless of CPAP use. There were no significant differences in complication rates between OSA patients with and without CPAP orders.

CONCLUSIONS

OSA appears to be independently associated with a higher risk for ER visits, PE and respiratory arrest following knee arthroscopy after controlling for demographic and comorbidity confounders. An order for CPAP was not associated with a significant reduction the risk for these complications. CPAP noncompliance may not be as important a factor when risk stratifying patients undergoing ambulatory knee arthroscopy compared to more significant medical comorbidities.

LEVEL OF EVIDENCE

III.

Risk factors for opioid-induced respiratory depression in surgical patients: a systematic review and meta-analyses

OBJECTIVE

This systematic review and meta-analysis aim to evaluate the risk factors associated with postoperative opioid-induced respiratory depression (OIRD).

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed-MEDLINE, MEDLINE in-process, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, PubMed and Clinicaltrials.gov (January 1946 to November 2017).

ELIGIBILITY CRITERIA

The inclusion criteria were: (1) adult patients 18 years or older who were administered opioids after surgery and developed postoperative OIRD (OIRD group); (2) all studies which reported both OIRD events and associated risk factors; (3) all studies with reported data for each risk factor on patients with no OIRD (control group) and (4) published articles in English language.

DATA ANALYSIS

We used a random effects inverse variance analysis to evaluate the existing evidence of risk factors associated with OIRD. Newcastle-Ottawa scale scoring system was used to assess quality of study.

RESULTS

Twelve observational studies were included from 8690 citations. The incidence of postoperative OIRD was 5.0 cases per 1000 anaesthetics administered (95% CI: 4.8 to 5.1; total patients: 841 424; OIRD: 4194). Eighty-five per cent of OIRD occurred within the first 24 hours postoperatively. Increased risk for OIRD was associated with pre-existing cardiac disease (OIRD vs control: 42.8% vs 29.6%; OR: 1.7; 95% CI: 1.2 to 2.5; I²: 0%; p<0.002), pulmonary disease (OIRD vs control: 17.8% vs 10.3%; OR: 2.2; 95% CI: 1.3 to 3.6; I²: 0%; p<0.001) and obstructive sleep apnoea (OIRD vs control: 17.9% vs 16.5%; OR: 1.4; 95% CI: 1.2 to 1.7; I²: 31%; p=0.0003). The morphine equivalent daily dose of the postoperative opioids was higher in the OIRD group than in the control; (24.7±14 mg vs 18.9±13.0 mg; mean difference: 2.8; 95% CI: 0.4 to 5.3; I²: 98%; p=0.02). There was no significant association between OIRD and age, gender, body mass index or American Society of Anesthesiologists physical status.

CONCLUSION

Patients with cardiac, respiratory disease and/or obstructive sleep apnoea were at increased risk for OIRD. Patients with postoperative OIRD received higher doses of morphine equivalent daily dose.

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.

Preoperative Laboratory Testing

Obtaining routine preoperative laboratory tests increases health care costs and has been listed, by the Choosing Wisely Campaign, as one of the top 5 practices anesthesiologists should avoid. Routine testing without clinical indication is not cost-effective and could cause harm and unnecessary delays. Abnormal findings are more likely to be false positive and costly to pursue, introduce new risks, and increase anxiety for the patient. Preoperative testing need to be performed only following a targeted history and physical examination, factoring severity of surgery, and comorbidities such that the benefit of the test outweighs risk.

Is obstructive sleep apnea associated with difficult airway? Evidence from a systematic review and meta-analysis of prospective and retrospective cohort studies

BACKGROUND

Difficult airway management and obstructive sleep apnea may contribute to increased risk of perioperative morbidity and mortality. The objective of this systematic review and meta-analysis (SRMA) is to evaluate the evidence of a difficult airway being associated with obstructive sleep apnea (OSA) patients undergoing surgery.

METHODS

The standard databases were searched from 1946 to April 2017 to identify the eligible articles. The studies which included adult surgical patients with either suspected or diagnosed obstructive sleep apnea must report at least one difficult airway event [either difficult intubation (DI), difficult mask ventilation (DMV), failed supraglottic airway insertion or difficult surgical airway] in sleep apnea and non-sleep apnea patients were included.

RESULTS

Overall, DI was 3.46-fold higher in the sleep apnea vs non-sleep apnea patients (OSA vs. non-OSA: 13.5% vs 2.5%; OR 3.46; 95% CI: 2.32-5.16, p <0.00001). DMV was 3.39-fold higher in the sleep apnea vs non-sleep apnea patients (OSA vs. non-OSA: 4.4% vs 1.1%; OR 3.39; 95% CI: 2.74-4.18, p <0.00001). Combined DI and DMV was 4.12-fold higher in the OSA vs. non-OSA patients (OSA vs. non-OSA: 1.1% vs 0.3%; OR 4.12; 95% CI: 2.93-5.79, p <0.00001). There was no significant difference in the supraglottic airway failure rates in the sleep apnea vs non-sleep apnea patients (OR: 1.34; 95% CI: 0.70-2.59; p = 0.38). Meta-regression to adjust for various subgroups and baseline confounding factors did not impact the final inference of our results.

CONCLUSION

This SRMA found that patients with obstructive sleep apnea had a three to four-fold higher risk of difficult intubation or mask ventilation or both, when compared to non-sleep apnea patients.

Anesthesia Preoperative Clinic Evaluation of Obstructive Sleep Apnea Using Nasal Fiberoptic Videoendoscopy: A Pilot Study Comparison with Polysomnography

Background

Nasal fiberoptic videoendoscopy is an established technique to assess upper airway pathology in conscious and sedated patients.

Objectives

The authors conducted a prospective proof-of-concept pilot study to evaluate whether airway narrowing detected using nasal fiberoptic videoendoscopy in the anesthesia preoperative clinic was capable of defining the severity of obstructive sleep apnea (OSA) in patients scheduled for elective surgery.

Methods

After application of topical local anesthesia (4% lidocaine with phenylephrine), sixteen patients (ASA physical status 2 or 3) underwent nasal fiberoptic videoendoscopy in sitting position. The magnitudes of retropalatal and retrolingual luminal narrowing were assessed as predictors of OSA. Patients also underwent polysomnography and completed STOP-Bang questionnaires. The endoscopist's clinical impression of OSA severity based on the history and airway examination was quantified.

Results

Retropalatal luminal narrowing and STOP-Bang score ≥ 4 predicted OSA severity as either "none or mild" or "moderate to severe" in 13 (81%) and 9 (56%) of 16 patients who underwent polysomnography, respectively. OSA severity was significantly (Spearman's rank correlation coefficient) associated with retropalatal airway narrowing (P = 0.0048), STOP-BANG score (P = 0.0072), and body mass index (P = 0.0091), whereas clinical impression and retrolingual pharyngeal narrowing were not (P=0.093 and P = 0.11, respectively).

Conclusions

The current results suggest that nasal fiberoptic videoendoscopy quantification of retropalatal airway narrowing may be a useful tool for assessing the severity of OSA in the anesthesia preoperative clinic. The current findings document a proof-of-concept feasibility of nasal fiberoptic videoendoscopy as a screening tool for OSA in conscious patients during preoperative evaluation that may justify further prospective clinical trials of this technique.