Literature Updates from March 2019

Impact of obstructive sleep apnea on perioperative complications among patients undergoing hysterectomy: a population-based analysis.

In this study data on patients who underwent a hysterectomy between 2006 and 2014 from a large nationwide database (n = 459,508) was investigated. OSA patients (identified by ICD-9 CM codes) were compared to non-OSA patients regarding perioperative outcomes: cardiac, central-nervous, gastrointestinal, genitourinary, renal, respiratory, and thromboembolic complications; as well as opioid prescription, need for blood transfusion, cost of hospitalization, length of stay and ICU admission. Results showed that among patients undergoing hysterectomies, OSA was associated with substantially increased risk of complications and modestly increased resource utilization. Therefore, further research is needed to assess perioperative care strategies to improve outcomes in patients with OSA.

Perioperative impact of sleep apnea in a high-volume specialty practice with a strong focus on regional anesthesia: a database analysis.

The authors studied the impact of OSA on postoperative complications in a high-volume orthopedic surgery practice, with a strong focus on regional anesthesia. Cases of primary total hip and knee arthroplasties performed at the Hospital for Special Surgery from 2005 to 2014 were extracted (N=41, 766), of which around 90% under neuraxial anesthesia. Overall, OSA was seen in 6.3% (n=1332) of patients with THA and 9.1% (n=1896) of patients with TKA. After adjustment for relevant covariates, OSA was significantly associated with 87% (OR 1.87, 95% CI 1.51 to 2.30), 52% (OR 1.52, 95% CI 1.13 to 2.04), and 44% (OR 1.44,95% CI 1.31 to 1.57) increased odds for pulmonary gastrointestinal complications, and prolonged LOS, respectively. This shows that even in a setting of almost universal utilization of regional anesthesia, OSA was associated with increased odds for prolonged LOS, and pulmonary and gastrointestinal complications. This puts forward the question of how effective regional anesthesia is in mitigating postoperative complications in patients with OSA.

Non-opioid analgesic modes of pain management are associated with reduced postoperative complications and resource utilisation: a retrospective study of obstructive sleep apnoea patients undergoing elective joint arthroplasty.

This population-based retrospective cohort study aimed to assess the impact of multimodal analgesia on opioid use and complications among OSA patients undergoing elective lower extremity joint arthroplasty. Multimodal analgesia was defined as opioid use with the addition of one, two, or more non-opioid analgesic modes including, nonsteroidal anti-inflammatory drugs (NSAIDs), cyclooxygenase-2 inhibitors, paracetamol/acetaminophen, peripheral nerve blocks, steroids, gabapentin/pregabalin, or ketamine. Multilevel multivariable regression models measured associations between multimodal analgesia and opioid prescription, opioid- and OSA-related complications, and resource utilization.

Among 181 182 OSA patients results showed stepwise beneficial postoperative outcome effects with increasing additional analgesic modes compared with opioid-only analgesia. In patients who received more than two additional analgesia modes (n = 64 174), opioid dose prescription decreased by 14.9% (CI -17.0%; -12.7%), while odds were significantly decreased for gastrointestinal complications (OR 0.65, CI 0.53; 0.78), mechanical ventilation (OR 0.23, CI 0.16; 0.32), and critical care admission (OR 0.60, CI 0.48; 0.75), all P<0.0001. In a population at high risk for perioperative complications from OSA, multimodal analgesia was associated with a stepwise reduction in opioid use and complications, including critical respiratory failure.

Sleep Study and Oximetry Parameters for Predicting Postoperative Complications in Patients With OSA.

The objective of this systematic review was to evaluate the literature to determine the association between parameters extracted from in-laboratory PSG, portable PSG, or overnight oximetry and postoperative adverse events. Pertinent articles were obtained including studies with adult surgical OSA patients that reported on specific sleep parameters and adverse outcomes. The search yielded 1,810 articles, of which 21 were included in the review. Preoperative apnea-hypopnea index (AHI) and measurements of nocturnal hypoxemia such as oxygen desaturation index (ODI), cumulative sleep time percentage with oxyhemoglobin saturation (Spo2) < 90% (CT90), minimum Spo2, mean Spo2, and longest apnea duration were associated with postoperative complications. Clinically and statistically significant associations between AHI and postoperative adverse events exists. Complications may be more likely to occur in the category of moderate to severe OSA (AHI ≥ 15). Other parameters from PSG or overnight oximetry such as ODI, CT90, mean and minimal Spo2, and longest apnea duration can be associated with postoperative complications and may provide additional value in risk stratification and minimization.

The effect of obstructive sleep apnea on readmissions and atrial fibrillation after cardiac surgery.

The study objective was to understand the effect of obstructive sleep apnea on readmission rates and post-operative atrial fibrillation in the cardiac surgical population.

The authors utilized an administrative database consisting of 2007-2014 data from California, Florida, New York, Kentucky, and Maryland from the State Inpatient Databases, Healthcare Cost and Utilization A total of 506,604 patients ≥18 years old who underwent coronary artery bypass grafting surgery (CABG) and/or valve surgery were included in the study. After excluding for death during the index hospitalization and missing data, 396,657 patients remained for 30-day readmission analysis. Results showed that patients with OSA are at increased risk of 30-day readmission and post-operative atrial fibrillation following cardiac surgery compared to those without OSA.

Comparison of genioglossus muscle activity and efficiency of dexmedetomidine or propofol during drug-induced sleep endoscopy in patients with obstructive sleep apnea/hypopnea syndrome.

The purpose of this study was to evaluate the hemodynamic and respiratory effects of dexmedetomidine vs. propofol in patients with OSAHS during the drug-induced sleep endoscopy (DISE), while simultaneously analyzing the electromyography of genioglossus muscle. The study included 50 patients with OSAHS, who were subjected to DISE with simultaneous polygraphic cardiorespiratory measurement and electromyography of the genioglossus muscle. Patients undergoing DISE received either propofol or dexmedetomidine. A greater worsening of the cardio-respiratory basal values was noted after sleep induction with Propofol and same results were obtained confronting EMG of genioglossus muscle data.

Preoperative Assessment of Obstructive Sleep Apnea in the Ambulatory Anesthesia Patient: A Survey of Oral and Maxillofacial Surgery Providers.

The purpose of this study was to determine whether oral and maxillofacial surgery providers are screening patients for perioperative and postoperative risks related to OSA before office-based ambulatory anesthesia.

SurveyMonkey software (SurveyMonkey, San Mateo, CA) was used to distribute a survey to 1,658 community- and hospital-based OMS providers in the United States. A response rate of 17.4% (n = 288) was achieved. Results showed that most of the surveyed maxillofacial surgery providers are not screening pre-anesthesia patients for OSA with a quantifiable method such as the STOP-Bang questionnaire. These findings identify a need to investigate the rate of undiagnosed OSA syndrome in the OMS office-based ambulatory anesthesia patient population. The STOP-Bang questionnaire may be a useful tool to better assess for anesthesia risk and modify management accordingly.

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

This systematic review and meta-analysis aim to evaluate the risk factors associated with postoperative opioid-induced respiratory depression (OIRD). Twelve observational studies were included and the incidence of postoperative OIRD was 5.0 cases per 1000 anaesthetics administered. Eighty-five per cent of OIRD occurred within the first 24 hours postoperatively. 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.

Non-steady State Modeling of the Ventilatory Depressant Effect of Remifentanil in Awake Patients Experiencing Moderate-to-severe Obstructive Sleep Apnea.

The aim of this prospective study was to evaluate the sensibility of moderate-to-severe OSA patients to remifentanil-induced ventilatory depression. These patients were matched with control patients. Interestingly, the results demonstrate that OSA patients were not influence by opioids in terms of ventilatory depression. To the best of our knowledge, this was the first time that such results were highlighted.

Evaluation of validity of the STOP-BANG questionnaire in major elective noncardiac surgery.

In this retrospective cohort study of patients undergoing major elective noncardiac surgery (n = 26 068), the authors aimed to evaluate the validity of the STOP-Bang score. After risk-adjustment, STOP-Bang score was not associated with mortality, morbidity, or length-of-stay.