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

Anesthesia for the Patient Undergoing Foot and Ankle Surgery

Modern anesthetic management for foot and ankle surgery includes a variety of anesthesia techniques including general anesthesia, neuraxial anesthesia, or MAC in combination with peripheral nerve blocks and/or multimodal analgesic agents. The choice of techniques should be tailored to the nature of the procedure, patient comorbidities, anesthesiologist skill level, intensity of anticipated postoperative pain, and surgeon preference.

The Perioperative Use of Benzodiazepines for Major Orthopedic Surgery in the United States

BACKGROUND

Despite numerous indications for perioperative benzodiazepine use, associated risks may be exacerbated in elderly and comorbid patients. In the absence of national utilization data, we aimed to describe utilization patterns using national claims data from total hip/knee arthroplasty patients (THA/TKA), an increasingly older and vulnerable surgical population.

METHODS

We included data on 1,863,996 TKAs and 985,471 THAs (Premier Healthcare claims data, 2006-2019). Benzodiazepine utilization (stratified by long- and short-acting agents) was assessed by patient- and health care characteristics, and analgesic regimens. Given the large sample size, standardized differences instead of P values were utilized to signify meaningful differences between groups (defined by value >0.1).

RESULTS

Among 1,863,996 TKA and 985,471 THA patients, the utilization rate of benzodiazepines was 80.5% and 76.1%, respectively. In TKA, 72.6% received short-acting benzodiazepines, while 7.9% received long-acting benzodiazepines, utilization rates 68.4% and 7.7% in THA, respectively. Benzodiazepine use was particularly more frequent among younger patients (median age [interquartile range {IQR}]: 66 [60-73]/64 [57-71] among short/long-acting compared to 69 [61-76] among nonusers), White patients (80.6%/85.4% short/long-acting versus 75.7% among nonusers), commercial insurance (36.5%/34.0% short/long-acting versus 29.1% among nonusers), patients receiving neuraxial anesthesia (56.9%/56.5% short/long-acting versus 51.5% among nonusers), small- and medium-sized (≤500 beds) hospitals (68.5% in nonusers, and 74% and 76.7% in short- and long-acting benzodiazepines), and those in the Midwest (24.6%/25.4% short/long-acting versus 16% among nonusers) in TKA; all standardized differences ≥0.1. Similar patterns were observed in THA except for race and comorbidity burden. Notably, among patients with benzodiazepine use, in-hospital postoperative opioid administration (measured in oral morphine equivalents [OMEs]) was substantially higher. This was even more pronounced in patients who received long-acting agents (median OME with no benzodiazepines utilization 192 [IQR, 83-345] vs 256 [IQR, 153-431] with short-acting, and 329 [IQR, 195-540] with long-acting benzodiazepine administration). Benzodiazepine use was also more frequent in patients receiving multimodal analgesia (concurrently 2 or more analgesic modes) and regional anesthesia. Trend analysis showed a persistent high utilization rate of benzodiazepines over the last 14 years.

CONCLUSIONS

Based on a representative sample, 4 of 5 patients undergoing major orthopedic surgery in the United States receive benzodiazepines perioperatively, despite concerns for delirium and delayed postoperative neurocognitive recovery. Notably, benzodiazepine utilization was coupled with substantially increased opioid use, which may project implications for perioperative pain management.

Evaluation of Monitored Anesthesia Care Involving Sedation and Axillary Nerve Block for Day-Case Hand Surgery

Background: Ultrasound-guided axillary brachial plexus block (ABPB) is a technique of choice for regional anesthesia during hand and forearm surgery. Intravenous sedation may facilitate this procedure, particularly for those suffering from anxiety; however, it can also be associated with respiratory, cardiovascular, and neurological side effects. The objective of this study was to evaluate the effect of intravenous sedation on perioperative respiratory depression for patients undergoing day-case hand surgery under ABPB. Methods: A prospective, observational, single-center study was conducted between 1 May and 1 November 2016. Results: A total of 2318 patients were included, with 501 patients in the group with IV sedation and 1817 in the group without. A multivariable propensity-score matched analysis showed that the variables associated with the number of desaturation were: (i) sedation (aRR 1.534 [95% CI: 1.283 to 1.836]), (ii) age and sex, (iii) type of surgery, and iv) Body Mass Index (BMI). Conclusions: Supplementing ABPB with IV sedation was associated with an increased rate of respiratory depression (episodes of desaturation) compared to fully awakened patients. The rate of oxygen administration was also higher in sedated patients even though they had fewer cases of chronic respiratory diseases and fewer were active smokers than non-sedated patients. Future research should consider precisely evaluating patient satisfaction, as well as the differences between sedation and drug-free approaches.

Anesthetic Implications for Patients With Implanted Hypoglossal Nerve Stimulators: A Case Report

Obstructive sleep apnea is a serious health issue affecting more than one billion people worldwide. Although continuous positive airway pressure is the mainstay for the treatment of obstructive sleep apnea, hypoglossal nerve stimulation is a surgical option for patients who are unable to tolerate or adhere to this therapy. As more hypoglossal nerve stimulators are implanted, these patients will present with increasing frequency for medical procedures requiring general anesthesia or deep sedation. We describe our experience with one such patient and hope this information can be used to develop future guidelines to aid in the anesthetic management of these patients.

Patients with sleep-disordered breathing for bariatric surgery

The prevalence of patients with obesity continues to rise worldwide and has reached epidemic proportions. There is a strong correlation between obesity and sleep-disordered breathing (SDB), and, in particular, obstructive sleep apnea (OSA). OSA is often undiagnosed in the surgical population. Bariatric surgery has been recognized as an effective treatment option for both obesity and OSA. Laparoscopic bariatric procedures, particularly laparoscopic sleeve gastrectomy (LSG), have become the most frequently performed procedures. OSA has been identified as an independent risk factor for perioperative complications and failure to recognize and prepare for patients with OSA is a major cause of postoperative adverse events, suggesting that all patients undergoing bariatric surgery should be screened preoperatively for OSA. These patients should be treated with an opioid-sparing analgesic plan and continuous positive airway pressure (CPAP) perioperatively to minimize respiratory complications. With the number of bariatric surgical patients with SDB likely to continue rising, it is critical to understand the best practices to manage this patient population.

The influence of acute morphine use on obstructive sleep apnea: A systematic review and meta-analysis

The present study was conducted to systematically evaluate the acute effect of morphine on obstructive sleep apnea (OSA). The PubMed, Embase, Cochrane Library, Clinicaltrials.gov, China National Knowledge Infrastructure (CNKI), and Wan-Fang databases were searched for randomised controlled trials studying the influence of morphine on OSA published up to May 24, 2021. The Cochrane risk of bias tool was used to assess study quality and meta-analysis was performed on the included clinical trial results to quantify the impact of morphine on various sleep and respiratory parameters. Three studies (n = 132 patients) were ultimately examined. There were no significant differences between patients with OSA taking morphine and placebo/non-opioids with respect to the sleep Apnea-Hypopnea Index (mean difference [MD] 1.78, 95% confidence interval [CI] -2.41, 5.98; p > 0.05); Oxygen Desaturation Index (MD 1.49, 95% CI -3.21, 6.19; p > 0.05); Obstructive Sleep Apnea Index (MD 0.83, 95% CI -2.08, 3.75; p > 0.05); Hypopnea Index (MD -0.01, 95% CI -2.64, 2.63; p > 0.05); lowest oxygen saturation (MD 0.68, 95% CI -4.50, 5.86; p > 0.05); or sleep oxygen saturation >90% (MD 0.10, 95% CI -1.14, 1.34; p > 0.05). In conclusion, a single dose of 30 or 40 mg morphine does not have a significant effect on sleep or respiratory outcomes compared to placebo in patients with OSA, challenging the orthodoxy that opioids worsen OSA.

Postoperative cardiorespiratory complications and continuous positive airway pressure efficacy in obese patients undergoing noncardiac surgery

Background and Aims:

One in six Singaporeans has obstructive sleep apnoea (OSA) due to obesity compounded by inherent craniofacial features. We assessed the incidence of cardiopulmonary complications and the effectiveness of continuous positive airway pressure (CPAP) therapy in minimising such complications within an obese population.

Methods:

A retrospective study of elective noncardiac surgical patients with a body mass index ≥32 kg/m² was conducted. Patients at moderate to severe risk of OSA were offered CPAP therapy. CPAP therapy adherence, postoperative complications, length of hospital stay, and type of anaesthesia were analysed.

Results:

In total, 1400 patients comprising 174 with low risk of OSA (L-OSA) and 1226 with moderate to high risk of OSA were included. Of these, 332 were started on CPAP therapy (C-OSA) while 894 declined CPAP use (R-OSA). There were 10 (0.05%) cardiac events – one (0.6%) in the L-OSA group, six (0.6%) in the R-OSA group and three (0.9%) in the C-OSA group. There were 37 (2.6%) respiratory events – 2 (1.1%) in the L-OSA group, 23 (2.6%) in the R-OSA group, and 12 (3.6%) in the C-OSA group. Multivariate analysis showed no statistical significance in CPAP therapy minimising cardiac (P = 0.147) and respiratory (P = 0.255) complications, when analysed by intention-to-treat. CPAP therapy adherence was 13.6 and 10.2% pre- and postoperatively, respectively. When analysed per protocol, none of the nine patients compliant with both pre- and postoperative CPAP therapy developed cardiopulmonary complications.

Conclusions:

Amongst patients with moderate to severe risk of OSA, those who were compliant to perioperative CPAP therapy demonstrated a reduction in cardiopulmonary complications.

Analgesia and patient comfort after enhanced recovery after surgery in uvulopalatopharyngoplasty: a randomised controlled pilot study

Background

Uvulopalatopharyngoplasty(UPPP) is the most prevalent surgical treatment of obstructive sleep apnea, but postoperative pharyngeal pain may affect patient comfort. The enhanced recovery after surgery pathway has been proved beneficial to many types of surgery but not to UPPP yet. The aim of this pilot study was to preliminarily standrize an enhanced recovery after surgery protocol for UPPP, to assess whether it has positive effects on reducing postoperative pharyngeal pain and improving patient comfort, and to test its feasibility for an international multicentre study.

Methods

This randomised controlled study analysed 116 patients with obstructive sleep apnoea (OSA) who were undergoing UPPP in a single tertiary care hospital. They were randomly divided according to treatment: the ERAS group (those who received ERAS treatment) and the control group (those who received traditional treatment). Ninety-five patients completed the assessment (ERAS group, 59 patients; control group, 36 patients). Pharyngeal pain and patient comfort were evaluated using a visual analogue scale (VAS) at 30 min and at 6, 12, 24 and 48 h after UPPP. Complications, hospitalisation duration, and hospital cost were recorded.

Results

The VAS scores for resting pain and swallowing pain were significantly lower in the ERAS group than those in the control group at 30 min and at 6, 12, 24 and 48 h after surgery. Patient comfort was improved in the ERAS group. The hospitalisation duration and cost were comparable between the groups. The incidence of complications showed an increasing trend in the ERAS group.

Conclusion

The ERAS protocol significantly relieved pharyngeal pain after UPPP and improved comfort in patients with OSA, which showed the prospect for an larger study. Meanwhile a potential increase of post-operative complications in the ERAS group should be noticed.

Trial registration

Chinese Clinical Trial Registry (23/09/2018, ChiCTR1800018537)

Safety of restarting continuous positive airway pressure (CPAP) therapy following endoscopic endonasal skull base surgery

Objectives

Patients with obstructive sleep apnea (OSA) are at increased risk of perioperative and postoperative morbidity. The use of continuous positive airway pressure (CPAP) in the perioperative period may be of potential benefit. However, among patients who have undergone endonasal skull base surgery, many surgeons avoid prompt re‐initiation of CPAP therapy due to the theoretical increased risk of epistaxis, excessive dryness, pneumocephalus, repair migration, intracranial introduction of bacteria, and cerebrospinal fluid (CSF) leak. The objective of this article is to review the most up‐to‐date literature regarding when it is safe to resume CPAP usage in the patient undergoing endonasal skull base surgery.

Data Sources and Methods

This review combines the most recent literature as queried through PubMed regarding the safety of CPAP resumption following endonasal skull base surgery.

Results

Recent surveys of skull base surgeons demonstrate little consensus regarding the post‐operative management of OSA. Recent cadaveric studies suggest that approximately 85% of delivered CPAP pressures are transmitted to the sphenoid sinus. Further, at frequently prescribed CPAP pressure settings, common sellar reconstruction techniques maintain their integrity while preventing very little transmission of pressure into the sella. In small retrospective case series, patients with OSA who received CPAP immediately following transsphenoidal pituitary surgery had similar rates of surgical complications as OSA patients who did not receive CPAP in the immediate post‐operative period. Concerns of re‐initiating CPAP too early, such as the development of pneumocephalus, rarely develop.

Conclusions

There remains a paucity of objective data regarding when it is safe to resume CPAP following endonasal skull base surgery. Recent cadaveric studies and small retrospective case series suggest that it may be safe to resume CPAP earlier than is often practiced following endonasal skull base surgery.

There is no consensus regarding the time course of when it is safe to resume CPAP therapy following endonasal skull base surgery.

Following endonasal skull base surgery there are potentially unique risks of initiation of CPAP including epistaxis, excessive nasal crusting/drying, graft migration, pneumocephalus, CSF leak, and intracranial introduction of bacteria.

Cadaveric modeling suggests that only a fraction of the delivered CPAP pressure is actually transmitted into the sella, and even the simplest sellar repair techniques can withstand low to moderate pressures.

Small case series' do not demonstrate increased rate of post‐operative complications in patients with OSA who received CPAP immediately after surgery.

The decision to start CPAP postoperatively must be tailored to each patient based on the severity of his/her OSA, intraoperative findings, and the type of skull base repair employed.

Neuromuscular Blockade and Reversal Agent Practice Variability in the US Inpatient Surgical Settings

Introduction

The management of neuromuscular blockade (NMB) has evolved over time and remains a critical component of general anesthesia. However, NMB use varies by patient and procedural characteristics, clinical practices, protocols, and drug access. National utilization patterns are unknown. We describe changes in NMB and NMB reversal agent administration in surgical inpatients since the US introduction of sugammadex in December 2015.

Methods

In a retrospective observational study of inpatients involving NMB with rocuronium or vecuronium in the Premier Healthcare Database, we estimate associations between factors related to choice of (1) active NMB reversal versus spontaneous recovery and (2) sugammadex versus neostigmine as the reversal agent.

Results

Among 4.3 million adult inpatient encounters involving rocuronium or vecuronium, the most widely administered NMB agent was rocuronium alone (86%). Over time, gradual declines in both neostigmine use and spontaneous reversal were observed (64% and 36% in 2014 to 38% and 28%, respectively in the first half of 2019). Several factors were independently associated with use of active versus spontaneous NMB recovery including years since 2016, patient (age, race, comorbidities), and procedure (admission and surgery type) characteristics. Among those actively reversed, these and other factors were independently associated with choice of reversal agent administered, including size and teaching affiliation of hospital. While both impacted choices in treatment, the direction and magnitude of effect of patient comorbidities and procedure type varied in their impact on choice of mode (pharmacologic vs. spontaneous) and agent (neostigmine vs. sugammadex) of NMB reversal independent of other factors and each other. Sites which adopted sugammadex earlier were more likely to choose sugammadex over neostigmine compared with later adopters independent of other factors.

Conclusions

Among US adult inpatients administered NMBs, we observed complex relationships between patient, site, procedural characteristics, and NMB management choices as NMBA choice and active reversal options among inpatient cases changed over time.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-01835-2.

Neuromuscular blocking agents, medications that temporarily paralyze muscles, are used frequently during surgical procedures to facilitate intubation and patient immobility. Over time, muscle function can return spontaneously or through pharmacological reversal agents. This study looked at how the use of reversal agents in inpatients undergoing surgical procedures changed after a new reversal agent, sugammadex, became available for use in the USA in December 2015.

Medical records of 4.3 million adult patients treated with neuromuscular blocking agents (rocuronium or vecuronium) in the USA were studied. In 2014 (before sugammadex was available), one-third of patients (36%) recovered spontaneously from a neuromuscular blocking agent and two-thirds (64%) were treated with the reversal agent neostigmine. The use of both neostigmine and spontaneous recovery reduced gradually after sugammadex became available, so that by the first half of 2019, 38% of patients were treated with neostigmine and 28% of patients recovered spontaneously.

Whether or not a patient was treated with a reversal agent and what type of agent was chosen were affected by the length of time since 2016, patient characteristics, the type of surgical procedure that was performed as well as local hospital characteristics and practice differences.

Preoperative optimization of patients undergoing interventional procedures: infrastructure, logistics, and evidence-based medicine

PURPOSE OF REVIEW

Patients presenting for non-operating room procedures are often 'too sick' for surgery and require specific anesthesia care in remote areas with logistical and scheduling challenges.

RECENT FINDINGS

Increased complexity and scope of minimally invasive procedures have expanded this practice. In addition, the concept of therapeutic options other than conventional surgery is gaining traction.

SUMMARY

Our review of recent literature confirms the complexity and supports the safety of providing care in non-operating room anesthesia locations. Standard preanesthesia assessments and principles apply to these areas.

Association of Obstructive Sleep Apnea With Difficult Intubation: Prospective Multicenter Observational Cohort Study

BACKGROUND

Obstructive sleep apnea (OSA) has been found to be associated with difficult airway, although there is a paucity of prospective studies investigating thresholds of OSA severity with difficult airway outcomes. The aim of this study was to examine the association between OSA and difficult intubation or difficult mask ventilation. We also explored the utility of the Snoring, Tiredness, Observed apnea, high blood Pressure, Body mass index, Age, Neck circumference, and Gender (STOP-Bang) score for difficult airway prediction.

METHODS

The Postoperative Vascular Complications in Unrecognized Obstructive Sleep Apnea (POSA) trial was an international prospective cohort study of surgical patients 45 years or older with one or more cardiac risk factor presenting for noncardiac surgery, with planned secondary analyses of difficult airway outcomes. Multivariable logistic regression analyses tested associations between OSA severity and predictors of difficult airway with difficult intubation or difficult mask ventilation. Overall, 869 patients without prior diagnosis of OSA were screened for OSA risk with the STOP-Bang tool, underwent preoperative sleep study, and had routine perioperative care, including general anesthesia with tracheal intubation. The primary outcome analyzed was difficult intubation, and the secondary outcome was difficult mask ventilation.

RESULTS

Based on the sleep studies, 287 (33%), 324 (37%), 169 (20%), and 89 (10%) of the 869 patients had no, mild, moderate, and severe OSA, respectively. One hundred and seventy-two (20%) had a STOP-Bang score of 0-2 (low risk), 483 (55%) had a STOP-Bang score of 3-4 (intermediate risk), and 214 (25%) had a STOP-Bang score 5-8 (high risk). The incidence of difficult intubation was 6.7% (58 of 869), and difficult mask ventilation was 3.7% (32 of 869). Multivariable logistic regression demonstrated that moderate OSA (odds ratio [OR] = 3.26 [95% confidence interval {CI}, 1.37-8.38], adjusted P = .010) and severe OSA (OR = 4.05 [95% CI, 1.51-11.36], adjusted P = .006) but not mild OSA were independently associated with difficult intubation compared to patients without OSA. Relative to scores of 0-2, STOP-Bang scores of 3-4 and 5-8 were associated with increased odds of difficult intubation (OR = 3.01 [95% CI, 1.13-10.40, adjusted P = .046] and 4.38 [95% CI, 1.46-16.36, adjusted P = .014]), respectively. OSA was not associated with difficult mask ventilation, and only increasing neck circumference was found to be associated (adjusted P = .002).

CONCLUSIONS

Moderate and severe OSA were associated with difficult intubation, and increasing neck circumference was associated with difficult mask ventilation. A higher STOP-Bang score of 3 or more may be associated with difficult intubation versus STOP-Bang score of 0-2. Anesthesiologists should be vigilant for difficult intubation when managing patients suspected or diagnosed with OSA.

Levels of Evidence Supporting the North American and European Perioperative Care Guidelines for Anesthesiologists between 2010 and 2020: A Systematic Review

BACKGROUND

Although there are thousands of published recommendations in anesthesiology clinical practice guidelines, the extent to which these are supported by high levels of evidence is not known. This study hypothesized that most recommendations in clinical practice guidelines are supported by a low level of evidence.

METHODS

A registered (Prospero CRD42020202932) systematic review was conducted of anesthesia evidence-based recommendations from the major North American and European anesthesiology societies between January 2010 and September 2020 in PubMed and EMBASE. The level of evidence A, B, or C and the strength of recommendation (strong or weak) for each recommendation was mapped using the American College of Cardiology/American Heart Association classification system or the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. The outcome of interest was the proportion of recommendations supported by levels of evidence A, B, and C. Changes in the level of evidence over time were examined. Risk of bias was assessed using Appraisal of Guidelines for Research and Evaluation (AGREE) II.

RESULTS

In total, 60 guidelines comprising 2,280 recommendations were reviewed. Level of evidence A supported 16% (363 of 2,280) of total recommendations and 19% (288 of 1,506) of strong recommendations. Level of evidence C supported 51% (1,160 of 2,280) of all recommendations and 50% (756 of 1,506) of strong recommendations. Of all the guidelines, 73% (44 of 60) had a low risk of bias. The proportion of recommendations supported by level of evidence A versus level of evidence C (relative risk ratio, 0.93; 95% CI, 0.18 to 4.74; P = 0.933) or level of evidence B versus level of evidence C (relative risk ratio, 1.63; 95% CI, 0.72 to 3.72; P = 0.243) did not increase in guidelines that were revised. Year of publication was also not associated with increases in the proportion of recommendations supported by level of evidence A (relative risk ratio, 1.07; 95% CI, 0.93 to 1.23; P = 0.340) or level of evidence B (relative risk ratio, 1.05; 95% CI, 0.96 to 1.15; P = 0.283) compared to level of evidence C.

CONCLUSIONS

Half of the recommendations in anesthesiology clinical practice guidelines are based on a low level of evidence, and this did not change over time. These findings highlight the need for additional efforts to increase the quality of evidence used to guide decision-making in anesthesiology.

EDITOR’S PERSPECTIVE

[Uvulopalatoplasty with a severe form of obstructive sleep apnea: long-term results]

OBJECTIVE

To assess the severity of daytime sleepiness and the level of sleep apnea/hypopnea index (AHI), as well as the possibility of their correction, in the long-term period after uvulopalatoplasty (UPP) in patients suffering from obesity and obstructive sleep apnea syndrome (OSAS).

MATERIAL AND METHODS

We retrospectively analyzed the data of the patients, who requested a consultation due to nighttime snoring, witnessed sleep apneas and daytime drowsiness. We included men and women of ages 40 to 65 (24 male, 17 female) without cardiac or lung insufficiency. Group 1 consisted of 19 patients, who underwent UPP 3-5 years prior to current consultation. Group 2 consisted of 22 patients, who underwent UPP 6-12 earlier, despite prior diagnosis of severe OSAS. We performed cardiorespiratory sleep monitoring, additionally patients completed the Epworth scale and sleep quality scale. Patients were re-interviewed 2 months after initiation of CPAP therapy and or intraoral device treatment.

RESULTS

Group 1 (n=19) displayed obesity (Body Mass Index 34.2±6.1 kg/m²), severe OSAS (AHI 55.2±18.5), high level of daytime drowsiness (Epworth score 18.7±6.3) and low sleep quality (13.0±6.8 sleep quality score). Group 2 (n=22) displayed reduction in AHI level - significant statistically, but not clinically without changes in daytime drowsiness and sleep quality, which were improved in 29 cases out of 41 with the help of CPAP-therapy (18 cases) or intraoral fixation devices (11 cases).

CONCLUSION

UPP does not exert a clinically significant affect the severity of sleep disturbance in patients with obesity and severe OSAS. Night sleep study is essential before making a decision about UPP. Clinical state correction of patients in the long-term period of UPP is possible with the help of CPAP therapy or intraoral fixation devices.

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.

Differential Perioperative Outcomes in Patients With Obstructive Sleep Apnea, Obesity, or a Combination of Both Undergoing Open Colectomy: A Population-Based Observational Study

BACKGROUND

An increasing body of evidence demonstrates an association between obstructive sleep apnea (OSA) and adverse perioperative outcomes. However, large-scale data on open colectomies are lacking. Moreover, the interaction of obesity with OSA is unknown. This study examines the impact of OSA, obesity, or a combination of both, on perioperative complications in patients undergoing open colectomy. We hypothesized that while both obesity and OSA individually increase the likelihood for perioperative complications, the overlap of the 2 conditions is associated with the highest risk.

METHODS

Patients undergoing open colectomies were identified using the national Premier Healthcare claims-based Database (2006-2016; n = 340,047). Multilevel multivariable models and relative excess risk due to interaction (RERI) analysis quantified the impact of OSA, obesity, or both on length and cost of hospitalization, respiratory and cardiac complications, intensive care unit (ICU) admission, mechanical ventilation, and inhospital mortality.

RESULTS

Nine thousand twenty-eight (2.7%) patients had both OSA and obesity diagnoses; 10,137 (3.0%) had OSA without obesity; and 33,692 (9.9%) had obesity without OSA. Although there were overlapping confidence intervals in the binary outcomes, the risk increase was found highest for OSA with obesity, intermediate for obesity without OSA, and lowest for OSA without obesity. The strongest effects were seen for respiratory complications: odds ratio (OR), 2.41 (2.28-2.56), OR, 1.40 (1.31-1.49), and OR, 1.50 (1.45-1.56), for OSA with obesity, OSA without obesity, and obesity without OSA, respectively (all P < .0001). RERI analysis revealed a supraadditive effect of 0.51 (95% confidence interval [CI], 0.34-0.68) for respiratory complications, 0.11 (-0.04 to 0.26) for cardiac complications, 0.30 (0.14-0.45) for ICU utilization, 0.34 (0.21-0.47) for mechanical ventilation utilization, and 0.26 (0.15-0.37) for mortality in patients with both OSA and obesity, compared to the sum of the conditions' individual risks. Inhospital mortality was significantly higher in patients with both OSA and obesity (OR [CI], 1.21 [1.07-1.38]) but not in the other groups.

CONCLUSIONS

Both OSA and obesity are individually associated with adverse perioperative outcomes, with a supraadditive effect if both OSA and obesity are present. Interventions, screening, and perioperative precautionary measures should be tailored to the respective risk profile. Moreover, both conditions appear to be underreported compared to the general population, highlighting the need for stringent perioperative screening, documentation, and reporting.

Identification of Sleep Medicine and Anesthesia Core Topics for Anesthesia Residency: A Modified Delphi Technique Survey

BACKGROUND

Sleep disorders affect up to 25% of the general population and are associated with increased risk of adverse perioperative events. The key sleep medicine topics that are most important for the practice of anesthesiology have not been well-defined. The objective of this study was to determine the high-priority sleep medicine topics that should be included in the education of anesthesia residents based on the insight of experts in the fields of anesthesia and sleep medicine.

METHODS

We conducted a prospective cross-sectional survey of experts in the fields of sleep medicine and anesthesia based on the Delphi technique to establish consensus on the sleep medicine topics that should be incorporated into anesthesia residency curricula. Consensus for inclusion of a topic was defined as >80% of all experts selecting "agree" or "strongly agree" on a 5-point Likert scale. Responses to the survey questions were analyzed with descriptive statistical methods and presented as percentages or weighted mean values with standard deviations (SD) for Likert scale data.

RESULTS

The topics that were found to have 100% agreement among experts were the influence of opioids and anesthetics on control of breathing and upper airway obstruction; potential interactions of wake-promoting/hypnotic medications with anesthetic agents; effects of sleep and anesthesia on upper airway patency; and anesthetic management of sleep apnea. Less than 80% agreement was found for topics on the anesthetic implications of other sleep disorders and future pathways in sleep medicine and anesthesia.

CONCLUSIONS

We identify key topics of sleep medicine that can be included in the future design of anesthesia residency training curricula.

Perioperative Management of 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.

Obesity and Obesity Hypoventilation, Sleep Hypoventilation, and Postoperative Respiratory Failure

Obesity hypoventilation syndrome (OHS) is considered as a diagnosis in obese patients (body mass index [BMI] ≥30 kg/m2) who also have sleep-disordered breathing and awake diurnal hypercapnia in the absence of other causes of hypoventilation. Patients with OHS have a higher burden of medical comorbidities as compared to those with obstructive sleep apnea (OSA). This places patients with OHS at higher risk for adverse postoperative events. Obese patients and those with OSA undergoing elective noncardiac surgery are not routinely screened for OHS. Screening for OHS would require additional preoperative evaluation of morbidly obese patients with severe OSA and suspicion of hypoventilation or resting hypoxemia. Cautious selection of the type of anesthesia, use of apneic oxygenation with high-flow nasal cannula during laryngoscopy, better monitoring in the postanesthesia care unit (PACU) can help minimize adverse perioperative events. Among other risk-reduction strategies are proper patient positioning, especially during intubation and extubation, multimodal analgesia, and cautious use of postoperative supplemental oxygen.

Pharmacologically Induced Ventilatory Depression in the Postoperative Patient: A Sleep-Wake State-Dependent Perspective

Pharmacologically induced ventilatory depression (PIVD) is a common postoperative complication with a spectrum of severity ranging from mild hypoventilation to severe ventilatory depression, potentially leading to anoxic brain injury and death. Recent studies, using continuous monitoring technologies, have revealed alarming rates of previously undetected severe episodes of postoperative ventilatory depression, rendering the recognition of such episodes by the standard intermittent assessment practice, quite problematic. This imprecise description of the epidemiologic landscape of PIVD has thus stymied efforts to understand better its pathophysiology and quantify relevant risk factors for this postoperative complication. The residual effects of various perianesthetic agents on ventilatory control, as well as the multiple interactions of these drugs with patient-related factors and phenotypes, make postoperative recovery of ventilation after surgery and anesthesia a highly complex physiological event. The sleep-wake, state-dependent variation in the control of ventilation seems to play a central role in the mechanisms potentially enhancing the risk for PIVD. Herein, we discuss emerging evidence regarding the epidemiology, risk factors, and potential mechanisms of PIVD.

Trends in Comorbidities and Complications Among Patients Undergoing Hip Fracture Repair

BACKGROUND

Hip fracture patients represent various perioperative challenges related to their significant comorbidity burden and the high incidence of morbidity and mortality. As population trend data remain rare, we aimed to investigate nationwide trends in the United States in patient demographics and outcomes in patients after hip fracture repair surgery.

METHODS

After Institutional Review Board (IRB) approval (IRB#2012-050), data covering hip fracture repair surgeries were extracted from the Premier Healthcare Database (2006-2016). Patient demographics, comorbidities, and complications, as well as anesthesia and surgical details, were analyzed over time. Cochran-Armitage trend tests and simple linear regression assessed significance of (linear) trends.

RESULTS

Among N = 507,274 hip fracture cases, we observed significant increases in the incidence in preexisting comorbid conditions, particularly the proportion of patients with >3 comorbid conditions (33.9% to 43.4%, respectively; P < .0001). The greatest increase for individual comorbidities was seen for sleep apnea, drug abuse, weight loss, and obesity. Regarding complications, increased rates over time were seen for acute renal failure (from 6.9 to 11.1 per 1000 inpatient days; P < .0001), while significant decreasing trends for mortality, pneumonia, hemorrhage/hematoma, and acute myocardial infarction were recorded. In addition, decreasing trends were observed for the use of neuraxial anesthesia either used as sole anesthetic or combined with general anesthesia (7.3% to 3.6% and 6.3% to 3.4%, respectively; P < .0001). Significantly more patients (31.9% vs 41.3%; P < .0001) were operated on in small rather than medium- and large-sized hospitals.

CONCLUSIONS

From 2006 to 2016, the overall comorbidity burden increased among patients undergoing hip fracture repair surgery. Throughout this same time period, incidence of postoperative complications either remained constant or declined with the only significant increase observed in acute renal failure. Moreover, use of regional anesthesia decreased over time. This more comorbid patient population represents an increasing burden on the health care system; however, existing preventative measures appear to be effective in minimizing complication rates. Although, given the proposed benefits of regional anesthesia, decreased utilization may be of concern.

Stickler Syndrome: Airway Complications in a Case Series of 502 Patients

BACKGROUND

Patients with Stickler syndrome often require emergency surgery and are often anesthetized in nonspecialist units, typically for retinal detachment repair. Despite the occurrence of cleft palate and Pierre-Robin sequence, there is little published literature on airway complications. Our aim was to describe anesthetic practice and complications in a nonselected series of Stickler syndrome cases. To our knowledge, this is the largest such series in the published literature.

METHODS

We retrospectively identified patients with genetically confirmed Stickler syndrome who had undergone general anesthesia in a major teaching hospital, seeking to identify factors that predicted patients who would require more than 1 attempt to correctly site an endotracheal tube (ETT) or supraglottic airway device (SAD). Patient demographics, associated factors, and anesthetic complications were collected. Descriptive statistical analysis and logistic regression modeling were performed.

RESULTS

Five hundred and twoanesthetic events were analyzed. Three hundred ninety-five (92.7%) type 1 Stickler and 63 (96.9%) type 2 Stickler patients could be managed with a single attempt of passing an ETT or SAD. Advanced airway techniques were required on 4 occasions, and we report no major complications. On logistic regression, modeling receding mandible (P = .0004) and history of cleft palate (P = .0004) were significantly associated with the need for more than 1 attempt at airway manipulation.

CONCLUSIONS

The majority of Stickler patients can be anesthetized safely with standard management. If patients have a receding mandible or history of cleft, an experienced anesthetist familiar with Stickler syndrome should manage the patient. We recommend that patients identified to have a difficult airway wear an alert bracelet.

Volatile Anesthetics Activate a Leak Sodium Conductance in Retrotrapezoid Nucleus Neurons to Maintain Breathing during Anesthesia in Mice

BACKGROUND

Volatile anesthetics moderately depress respiratory function at clinically relevant concentrations. Phox2b-expressing chemosensitive neurons in the retrotrapezoid nucleus, a respiratory control center, are activated by isoflurane, but the underlying mechanisms remain unclear. The hypothesis of this study was that the sodium leak channel contributes to the volatile anesthetics-induced modulation of retrotrapezoid nucleus neurons and to respiratory output.

METHODS

The contribution of sodium leak channels to isoflurane-, sevoflurane-, and propofol-evoked activity of Phox2b-expressing retrotrapezoid nucleus neurons and respiratory output were evaluated in wild-type and genetically modified mice lacking sodium leak channels (both sexes). Patch-clamp recordings were performed in acute brain slices. Whole-body plethysmography was used to measure the respiratory activity.

RESULTS

Isoflurane at 0.42 to 0.50 mM (~1.5 minimum alveolar concentration) increased the sodium leak channel-mediated holding currents and conductance from -75.0 ± 12.9 to -130.1 ± 34.9 pA (mean ± SD, P = 0.002, n = 6) and 1.8 ± 0.5 to 3.6 ± 1.0 nS (P = 0.001, n = 6), respectively. At these concentrations, isoflurane increased activity of Phox2b-expressing retrotrapezoid nucleus neurons from 1.1 ± 0.2 to 2.8 ± 0.2 Hz (P < 0.001, n = 5), which was eliminated by bath application of gadolinium or genetic silencing of sodium leak channel. Genetic silencing of sodium leak channel in the retrotrapezoid nucleus resulted in a diminished ventilatory response to carbon dioxide in mice under control conditions and during isoflurane anesthesia. Sevoflurane produced an effect comparable to that of isoflurane, whereas propofol did not activate sodium leak channel-mediated holding conductance.

CONCLUSIONS

Isoflurane and sevoflurane increase neuronal excitability of chemosensitive retrotrapezoid nucleus neurons partly by enhancing sodium leak channel conductance. Sodium leak channel expression in the retrotrapezoid nucleus is required for the ventilatory response to carbon dioxide during anesthesia by isoflurane and sevoflurane, thus identifying sodium leak channel as a requisite determinant of respiratory output during anesthesia of volatile anesthetics.

EDITOR’S PERSPECTIVE

Perioperative Care and Medication-related Hypoventilation

Cumulative evidence supports the association of adverse postoperative outcomes with obstructive sleep apnea (OSA) and obesity hypoventilation syndrome (OHS). Although current guidelines recommend preoperative screening for OSA and OHS, the best perioperative management pathways remain unknown. Interventions attempting to prevent complications in the postoperative period largely are consensus based and focused on enhanced monitoring, conservative measures, and specific OSA therapies, such as positive airway pressure. Until further research is available to improve the quality and strength of these recommendations, patients with known or suspected OSA and OHS should be considered at higher risk for perioperative cardiopulmonary complications.

Pulmonary complications in trauma patients with obstructive sleep apnea undergoing pelvic or lower limb operation

Background

Obstructive sleep apnea (OSA) is increasingly prevalent in the range of 2% to 24% in the US population. OSA is a well-described predictor of pulmonary complications after elective operation. Yet, data are lacking on its effect after operations for trauma. We hypothesized that OSA is an independent predictor of pulmonary complications in patients undergoing operations for traumatic pelvic/lower limb injuries (PLLI).

Methods

Nationwide Inpatient Sample (2009–2013) was queried for International Classification of Diseases, Ninth Revision, Clinical Modification codes for PLLI requiring operation. Elective admissions and those with concurrent traumatic brain injury with moderate to prolonged loss of consciousness were excluded. Outcome measures were pulmonary complications including ventilatory support, ventilator-associated pneumonia, pulmonary embolism (PE), acute respiratory distress syndrome (ARDS), and respiratory failure. Multivariable logistic regression analysis was used, adjusting for OSA, age, sex, race/ethnicity, and specific comorbidities (obesity, chronic lung disease, and pulmonary circulatory disease). P<0.01 was considered statistically significant.

Results

Among the 337 333 patients undergoing PLLI operation 3.0% had diagnosed OSA. Patients with OSA had more comorbidities and were more frequently discharged to facilities. Median length of stay was longer in the OSA group (5 vs 4 days, p<0.001). Pulmonary complications were more frequent in those with OSA. Multivariable logistic regression showed that OSA was an independent predictor of ventilatory support (adjusted odds ratio (aOR), 1.37; 95% CI,1.24 to 1.51), PE (aOR 1.40; 95% CI, 1.15 to 1.70), ARDS (aOR 1.36; 95% CI,1.23 to 1.52), and respiratory failure (aOR 1.90; 95% CI, 1.74 to 2.06).

Conclusion

OSA is an independent and underappreciated predictor of pulmonary complications in those undergoing emergency surgery for PLLI. More aggressive screening and identification of OSA in trauma patients undergoing operation are necessary to provide closer perioperative monitoring and interventions to reduce pulmonary complications and improve outcomes.

Level of evidence

Prognostic Level IV.

Risk of Postoperative Hyperalgesia in Adult Patients with Preoperative Poor Sleep Quality Undergoing Open-heart Valve Surgery

Purpose

Studies have reported that preoperative poor sleep quality could decrease the pain threshold in patients undergoing noncardiac surgery. However, the risk of postoperative hyperalgesia (HA) in cardiac surgery patients with preoperative poor sleep quality remains unclear.

Patients and Methods

We retrospectively collected clinical data from patients undergoing open-heart valve surgery between May 1 and October 31, 2019, in Fuwai Hospital (Beijing). We assessed preoperative sleep quality and postoperative pain severity using the Pittsburgh sleep quality index (PSQI) and numerical pain rating scale (NPRS), respectively. A PSQI of six or greater was considered to indicate poor sleep quality, and a NPRS of four or greater was considered to indicate HA. Multivariable logistic regression analysis was used to study the risk of postoperative HA in patients with preoperative poor sleep quality.

Results

We divided 214 eligible patients into two groups based on postoperative HA; HA group: n=61 (28.5%) and nonHA group: n=153 (71.5%). Compared with nonHA patients, patients with postoperative HA showed a higher percentage of history of smoking, 17 (11.1%) vs 15 (24.6%) and alcohol abuse, 5 (3.3%) vs 6 (9.8%), higher intraoperative dose of sufentanil (median, 1.02 vs 1.12 μg/kg/h), and longer duration of ventilation with tracheal catheter (median, 760 vs 934 min). Preoperative poor sleep quality was associated independently with an increased risk of postoperative HA (adjusted odds ratio [AOR]: 2.66; 95%CI: 1.31–5.39, P=0.007). Stratification by history of smoking revealed a stronger risk of postoperative HA in nonsmoking patients with preoperative poor sleep quality (AOR: 3.40; 95%CI: 1.51–7.66, P=0.003). No risk was found in patients who had history of smoking (AOR: 0.83; 95%CI: 0.14–4.75, P=0.832).

Conclusion

Preoperative poor sleep quality is an independent risk factor for postoperative HA in adult patients undergoing open-heart valve surgery who had no history of smoking.

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

BACKGROUND

Obstructive sleep apnea (OSA) patients are at increased risk for pulmonary and cardiovascular complications; perioperative mortality risk is unclear. This report analyzes cases submitted to the OSA Death and Near Miss Registry, focusing on factors associated with poor outcomes after an OSA-related event. We hypothesized that more severe outcomes would be associated with OSA severity, less intense monitoring, and higher cumulative opioid doses.

METHODS

Inclusion criteria were age ≥18 years, OSA diagnosed or suspected, event related to OSA, and event occurrence 1992 or later and <30 days postoperatively. Factors associated with death or brain damage versus other critical events were analyzed by tests of association and odds ratios (OR; 95% confidence intervals [CIs]).

RESULTS

Sixty-six cases met inclusion criteria with known OSA diagnosed in 55 (83%). Patients were middle aged (mean = 53, standard deviation [SD] = 15 years), American Society of Anesthesiologists (ASA) III (59%, n = 38), and obese (mean body mass index [BMI] = 38, SD = 9 kg/m); most had inpatient (80%, n = 51) and elective (90%, n = 56) procedures with general anesthesia (88%, n = 58). Most events occurred on the ward (56%, n = 37), and 14 (21%) occurred at home. Most events (76%, n = 50) occurred within 24 hours of anesthesia end. Ninety-seven percent (n = 64) received opioids within the 24 hours before the event, and two-thirds (41 of 62) also received sedatives. Positive airway pressure devices and/or supplemental oxygen were in use at the time of critical events in 7.5% and 52% of cases, respectively. Sixty-five percent (n = 43) of patients died or had brain damage; 35% (n = 23) experienced other critical events. Continuous central respiratory monitoring was in use for 3 of 43 (7%) of cases where death or brain damage resulted. Death or brain damage was (1) less common when the event was witnessed than unwitnessed (OR = 0.036; 95% CI, 0.007-0.181; P < .001); (2) less common with supplemental oxygen in place (OR = 0.227; 95% CI, 0.070-0.740; P = .011); (3) less common with respiratory monitoring versus no monitoring (OR = 0.109; 95% CI, 0.031-0.384; P < .001); and (4) more common in patients who received both opioids and sedatives than opioids alone (OR = 4.133; 95% CI, 1.348-12.672; P = .011). No evidence for an association was observed between outcomes and OSA severity or cumulative opioid dose.

CONCLUSIONS

Death and brain damage were more likely to occur with unwitnessed events, no supplemental oxygen, lack of respiratory monitoring, and coadministration of opioids and sedatives. It is important that efforts be directed at providing more effective monitoring for OSA patients following surgery, and clinicians consider the potentially dangerous effects of opioids and sedatives-especially when combined-when managing OSA patients postoperatively.

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.

Effects of Intraoperative Ketamine on Post-Operative Recovery in Obstructive Sleep Apnea Patients: A Case-Control Study

Objective

To evaluate the post-operative outcomes of patients with obstructive sleep apnea (OSA) given intraoperative ketamine.

Design: case-control study

A total of 574 patients (287 received ketamine and 287 were matched controls) diagnosed with OSA and body mass index (BMI) > 30 who received general anesthesia were included in this study. Patients given intraoperative ketamine were matched (1:1) with those who did not receive ketamine for age, gender, BMI, ethnicity, anesthesia time, intraoperative fentanyl dose, ketamine dose, and surgery type. A sub-analysis was performed based on the dose of ketamine administered and also on the surgery type. Measured outcomes include post-operative pain scores, post-operative opioid requirements, respiratory status, oxygen use, and duration post-operatively.

Results

Intraoperative ketamine use did not decrease pain scores or post-operative opioid use when compared with the control (no intraoperative ketamine) group. Patients who received high-dose ketamine had significantly higher post-operative pain scores (p=0.048) while in the post-anesthesia care unit (PACU) and required supplemental oxygen for a longer period of time (p = 0.030), pain scores were not significant for patients who underwent orthopedic/spine procedures (p = 0.074), and high-dose ketamine group patients who underwent orthopedic/spine surgery required significantly more opioids in the PACU (p = 0.031). Among patients who received low-dose ketamine, those who underwent head, ear, nose, and throat surgery required significantly more opioids in PACU (p = 0.022).

Conclusions

Low-dose intraoperative ketamine did not decrease pain scores or post-operative opioid use significantly and did not improve standard respiratory recovery parameters for OSA patients after surgery. Neither low- nor high-dose ketamine demonstrated the anticipated benefits of low pain scores and reduced post-operative opioid use. These outcomes will differ depending on the surgery type and dose of ketamine used.

Intrathecal Morphine and Pulmonary Complications after Arthroplasty in Patients with Obstructive Sleep Apnea

Background

Intrathecal morphine is commonly and effectively used for analgesia after joint arthroplasty, but has been associated with delayed respiratory depression. Patients with obstructive sleep apnea may be at higher risk of postoperative pulmonary complications. However, data is limited regarding the safety of intrathecal morphine in this population undergoing arthroplasty.

Methods

This retrospective cohort study aimed to determine the safety of intrathecal morphine in 1,326 patients with documented or suspected obstructive sleep apnea undergoing hip or knee arthroplasty. Chart review was performed to determine clinical characteristics, perioperative events, and postoperative outcomes. All patients received neuraxial anesthesia with low-dose (100 μg) intrathecal morphine (exposure) or without opioids (control). The primary outcome was any postoperative pulmonary complication including: (1) respiratory depression requiring naloxone; (2) pneumonia; (3) acute respiratory event requiring consultation with the critical care response team; (4) respiratory failure requiring intubation/mechanical ventilation; (5) unplanned admission to the intensive care unit for respiratory support; and (6) death from a respiratory cause. The authors hypothesized that intrathecal morphine would be associated with increased postoperative complications.

Results

In 1,326 patients, 1,042 (78.6%) received intrathecal morphine. The mean age of patients was 65 ± 9 yr and body mass index was 34.7 ± 7.0 kg/m2. Of 1,326 patients, 622 (46.9%) had suspected obstructive sleep apnea (Snoring, Tired, Observed, Pressure, Body Mass Index, Age, Neck size, Gender [STOP-Bang] score greater than 3), while 704 of 1,326 (53.1%) had documented polysomnographic diagnosis. Postoperatively, 20 of 1,322 (1.5%) patients experienced pulmonary complications, including 14 of 1,039 (1.3%) in the exposed and 6 of 283 (2.1%) in the control group (P = 0.345). Overall, there were 6 of 1 322 (0.5%) cases of respiratory depression, 18 of 1,322 (1.4%) respiratory events requiring critical care team consultation, and 4 of 1,322 (0.3%) unplanned intensive care unit admissions; these rates were similar between both groups. After adjustment for confounding, intrathecal morphine was not significantly associated with postoperative pulmonary complication (adjusted odds ratio, 0.60 [95% CI, 0.24 to 1.67]; P = 0.308).

Conclusions

Low-dose intrathecal morphine, in conjunction with multimodal analgesia, was not reliably associated with postoperative pulmonary complications in patients with obstructive sleep apnea undergoing joint arthroplasty.

Editor’s Perspective

What We Already Know about This Topic

What This Article Tells Us That Is New

Tracheal Ultrasound for the Accurate Confirmation of the Endotracheal Tube Position in Obese Patients

OBJECTIVES

Obesity is a serious disorder that may lead to numerous difficulties in endotracheal tube (ETT) management. This study investigated the potential of tracheal ultrasound (TUS) for the accurate confirmation of the ETT position in obese patients.

METHODS

A total of 68 obese patients undergoing tracheal intubation were enrolled in this study from January 2017 to June 2018. All patients received auscultation and TUS to evaluate the ETT position, which was ultimately verified by bronchoscopy. A correct position of the ETT was defined as placement at the trachea, whereas placement at the right/left main bronchus was classified as an incorrect position.

RESULTS

We found 58 correct placements of the ETT at the trachea, 8 incorrect placements at the right main bronchus, and 2 incorrect placements at the left main bronchus. Compared with auscultation, TUS showed higher accuracy (85.29% versus 67.65%; P = .005), sensitivity (84.48% versus 67.24%; P = .005), and specificity (90.00% versus 70.00%; P < .001), as well as lower rates of false-positive (10.00% versus 30.00%; P < .001) and false-negative (15.52% versus 32.76%; P = .005) results for detecting the correct placement of the ETT, defined as placement at the trachea.

CONCLUSIONS

Tracheal ultrasound is highly sensitive and specific in confirming the ETT position in obese patients.

Outcomes and Safety Among Patients With Obstructive Sleep Apnea Undergoing Cancer Surgery Procedures in a Freestanding Ambulatory Surgical Facility

BACKGROUND

Patients with obstructive sleep apnea (OSA) may be at increased risk for serious perioperative complications. The suitability of ambulatory surgery for patients with OSA remains controversial, and several national guidelines call for more evidence that assesses clinically significant outcomes. In this study, we investigate the association between OSA status (STOP-BANG risk, or previously diagnosed) and short-term outcomes and safety for patients undergoing cancer surgery at a freestanding ambulatory surgery facility.

METHODS

We conducted a retrospective analysis of all patients having surgery at the Josie Robertson Surgery Center, a freestanding ambulatory surgery facility of the Memorial Sloan Kettering Cancer Center. Surgeries included more complex ambulatory extended recovery procedures for which patients typically stay overnight, such as mastectomy, thyroidectomy, and minimally invasive hysterectomy, prostatectomy, and nephrectomy, as well as typical outpatient surgeries. Both univariate and multivariable analyses were used to assess the association between OSA risk and transfer to the main hospital, urgent care center visit, and hospital readmission within 30 days postoperatively (primary outcomes) and length of stay and discharge time (secondary outcomes). Multivariable models were adjusted for age, American Society of Anesthesiologists score, robotic surgery, and type of anesthesia (general or monitored anesthesia care) and also adjusted for surgery start time for length of stay and discharge time outcomes. χ tests were used to assess the association between OSA risk and respiratory events and device use.

RESULTS

Of the 5721 patients included in the analysis, 526 (9.2%) were diagnosed or at moderate or high risk for OSA. We found no evidence of a difference in length of stay when comparing high-risk or diagnosed patients with OSA to low- or moderate-risk patients whether they underwent outpatient (P = .2) or ambulatory extended recovery procedures (P = .3). Though a greater frequency of postoperative respiratory events were reported in high-risk or diagnosed patients with OSA compared to moderate risk (P = .004), the rate of hospital transfer was not significantly different between the groups (risk difference, 0.78%; 95% CI, -0.43% to 2%; P = .2). On multivariable analysis, there was no evidence of increased rate of urgent care center visits (adjusted risk difference, 1.4%; 95% CI, -0.68% to 3.4%; P = .15) or readmissions within 30 days (adjusted risk difference, 1.2%; 95% CI, -0.40% to 2.8%; P = .077) when comparing high-risk or diagnosed OSA to low- or moderate-risk patients. Based on the upper bounds of the CIs, a clinically relevant increase in transfers, readmissions, and urgent care center visits is unlikely.

CONCLUSIONS

Our results contribute to the body of evidence supporting that patients with moderate-risk, high-risk, or diagnosed OSA can safely undergo outpatient and advanced ambulatory oncology surgery without increased health care burden of extended stay or hospital admission and avoiding adverse postoperative outcomes. Our results support the adoption of several national OSA guidelines focusing on preoperative identification of patients with OSA and clinical pathways for perioperative management and postoperative monitoring.

Consistent Definitions of Clinical Practice Guidelines, Consensus Statements, Position Statements, and Practice Alerts

An evidence-based approach to clinical decision-making for optimizing patient care is desirable because it promotes quality of care, improves patient safety, decreases medical errors, and reduces health care costs. Clinical practice recommendations are systematically developed documents regarding best practice for specific clinical management issues, which can assist care providers in their clinical decision-making. However, there is currently wide variation in the terminology used for such clinical practice recommendations. The aim of this article is to provide guidance to authors, reviewers, and editors on the definitions of terms commonly used for clinical practice recommendations. This is intended to improve transparency and clarity regarding the definitions of these terminologies.