Subjective Assessment of Motor Function by the Bedside Nurses in Mechanically Ventilated Surgical Intensive Care Unit Patients Predicts Tracheostomy.

OBJECTIVE: In many institutions, intensive care unit (ICU) nurses assess their patients' muscle function as part of their routine bedside examination. We tested the research hypothesis that this subjective examination of muscle function prior to extubation predicts tracheostomy requirement. METHODS: Adult, mechanically ventilated patients admitted to 7 ICUs at Beth Israel Deaconess Medical Center (BIDMC) between 2008 and 2019 were included in this observational study. Assessment of motor function was performed every four hours by ICU nurses. Multivariable logistic regression analysis controlled for acute disease severity, delirium risk assessment through the confusion assessment method for the ICU (CAM-ICU), and pre-defined predictors of extubation failure was applied to examine the association of motor function and tracheostomy within 30 days after extubation. RESULTS: Within 30 days after extubation, 891 of 9609 (9.3%) included patients required a tracheostomy. The inability to spontaneously move and hold extremities against gravity within 24 h prior to extubation was associated with significantly higher odds of 30-day tracheostomy (adjusted OR 1.56, 95% CI 1.27-1.91, p < 0.001, adjusted absolute risk difference (aARD) 2.8% (p < 0.001)). The effect was magnified among patients who were mechanically ventilated for >7 days (aARD 21.8%, 95% CI 12.4-31.2%, p-for-interaction = 0.015). CONCLUSIONS: ICU nurses' subjective assessment of motor function is associated with 30-day tracheostomy risk, independent of known risk factors. Muscle function measurements by nursing staff in the ICU should be discussed during interprofessional rounds.

Preoperative anxiety.

PURPOSE OF REVIEW: With first research reports dating back to the 1970s, the important role of anxiety in the perioperative period has been recognized for a long time and remains in effect. RECENT FINDINGS: The global pooled prevalence of preoperative anxiety among 14 000 surgical patients was reported to be 48%. The underlying fears among surgical patients include: fear of surgical complications, worry about the duration and degree of disability after the procedure, concerns about general anesthesia and the associated loss of control, as well as fear of waking up and experiencing discomfort and pain during or after surgery. The type and invasiveness of the planned procedure contribute to differences in preoperative anxiety levels. While preoperative anxiety is higher in younger, female patients as well as in those with a high need for information, prior exposure to anesthesia or surgery was associated with lower anxiety levels. High levels of preoperative anxiety may lead to poor postoperative pain control and increased morbidity. Due to adverse effects such as delirium, the use of benzodiazepines to manage preoperative anxiety has decreased. SUMMARY: Preoperative anxiety remains a critical issue in the perioperative period. Further research is needed to develop effective management strategies, which may need to be tailored to the patient's individual need.

Pregnant and Postpartum Women Requiring Intensive Care Treatment for COVID-19-First Data from the CRONOS-Registry.

(1) Background: Data on coronavirus 2 infection during pregnancy vary. We aimed to describe maternal characteristics and clinical presentation of SARS-CoV-2 positive women requiring intensive care treatment for COVID-19 during pregnancy and postpartum period based on data of a comprehensive German surveillance system in obstetric patients. (2) Methods: Data from COVID-19 Related Obstetric and Neonatal Outcome Study (CRONOS), a prospective multicenter registry for SARS-CoV-2 positive pregnant women, was analyzed with respect to ICU treatment. All women requiring intensive care treatment for COVID-19 were included and compared regarding maternal characteristics, course of disease, as well as maternal and neonatal outcomes. (3) Results: Of 2650 cases in CRONOS, 101 women (4%) had a documented ICU stay. Median maternal age was 33 (IQR, 30-36) years. COVID-19 was diagnosed at a median gestational age of 33 (IQR, 28-35) weeks. As the most invasive form of COVID-19 treatment interventions, patients received either continuous monitoring of vital signs without further treatment requirement (n = 6), insufflation of oxygen (n = 30), non-invasive ventilation (n = 22), invasive ventilation (n = 28), or escalation to extracorporeal membrane oxygenation (n = 15). No significant clinical differences were identified between patients receiving different forms of ventilatory support for COVID-19. Prevalence of preterm delivery was significantly higher in women receiving invasive respiratory treatments. Four women died of COVID-19 and six fetuses were stillborn. (4) Conclusions: Our cohort shows that progression of COVID-19 is rare in pregnant and postpartum women treated in the ICU. Preterm birth rate is high and COVID-19 requiring respiratory support increases the risk of poor maternal and neonatal outcome.

Development and external validation of a prognostic model for ischaemic stroke after surgery.

BACKGROUND: There is an under-recognised patient cohort at elevated risk of postoperative ischaemic stroke. We aimed to develop and validate a prognostic model for the identification of such patients at high risk of ischaemic stroke within 1 yr after noncardiac surgery. METHODS: This was a hospital registry study of adult patients undergoing noncardiac surgery between 2005 and 2017 at two independent healthcare networks in Massachusetts, USA without a preoperative indication for therapeutic anticoagulation. Logistic regression was used to fit a model from a priori defined candidate predictors for the outcome 1 yr postoperative ischaemic stroke. To enhance clinical applicability, the model was simplified to a scoring system and externally validated. RESULTS: In the development (n=107 756) and validation (n=141 724) cohorts, 1.4% and 0.5% of patients had an ischaemic stroke up to 1 yr postoperatively. The final model included 13 variables (patient characteristics, comorbidities, procedural factors), considering sub-models conditional on a previous history of ischaemic stroke. Areas under the curve were 0.89 (95% confidence interval 0.89-0.90) and 0.88 (95% confidence interval 0.86-0.89) in the development and validation cohorts. Decision curve analysis indicated positive net benefits superior to other prediction instruments. CONCLUSIONS: Stroke after surgery (STRAS) screening can reliably identify patients with a high risk for ischaemic stroke during the first year after surgery. A STRAS-guided risk stratification may inform the recruitment to future randomised trials testing the efficacy of treatments for the prevention of postoperative ischaemic stroke.

Association between preoperative administration of gabapentinoids and 30-day hospital readmission: A retrospective hospital registry study.

STUDY OBJECTIVE: To evaluate the effectiveness of preoperative gabapentinoid administration. DESIGN: Retrospective hospital registry study. SETTING: Tertiary referral center (Boston, MA). PATIENTS: 111,008 adult non-emergency, non-cardiac surgical patients between 2014 and 2018. INTERVENTIONS: Preoperative administration of gabapentinoids (gabapentin or pregabalin). MEASUREMENTS: We tested the primary hypothesis that preoperative gabapentinoid use was associated with lower odds of hospital readmission within 30 days. Contingent on this hypothesis, we examined whether lower intraoperative opioid utilization mediated this effect. Secondary outcome was postoperative respiratory complications. MAIN RESULTS: Gabapentinoid administration was associated with lower odds of readmission (adjusted odds ratio [ORadj] 0.80 [95% CI, 0.75-0.85]; p < 0.001). This effect was in part mediated by lower intraoperative opioid utilization in patients receiving gabapentinoids (8.2% [2.4-11.5%]; p = 0.012). Readmissions for gastrointestinal disorders (ORadj 0.74 [0.60-0.90]; p = 0.003), neuro-psychiatric complications (ORadj 0.66 [0.49-0.87]; p = 0.004), non-surgical site infections (ORadj 0.68 [0.52-0.88; p = 0.004) and trauma or poisoning (ORadj 0.25 [0.16-0.41]; p < 0.001) occurred less frequently in patients receiving gabapentinoids. The risk of postoperative respiratory complications was lower in patients receiving gabapentinoids (ORadj 0.77 [0.70-0.85]; p < 0.001). Lower doses of pregabalin (< 75 mg) and gabapentin (< 300 mg) compared to both, no and high-dose administration of gabapentinoids, were associated with a lower risk of postoperative respiratory complications (ORadj 0.61 [0.50-0.75]; p < 0.001 and ORadj 0.70 [0.53-0.92]; p = 0.012, respectively). These lower gabapentinoid doses prevented 30-day readmission (ORadj 0.74 [0.65-0.85]; p < 0.001). The results were robust in several sensitivity analyses including surgical procedure defined subgroups and patients undergoing ambulatory surgery. CONCLUSIONS: The preoperative use of pregabalin and gabapentin, up to doses of 75 and 300 mg respectively, mitigates the risks of hospital readmission and postoperative respiratory complications which can in part be explained by lower intraoperative opioid use. Further research is warranted to elucidate mechanisms of the preventive action.

The effect of intraoperative dexmedetomidine administration on length of stay in the post-anesthesia care unit in ambulatory surgery: A hospital registry study.

STUDY OBJECTIVE: Dexmedetomidine, which is commonly used for procedural sedation and as adjunct to general anesthesia for ambulatory procedures, may affect patient discharge from the post-anesthesia care unit (PACU). We hypothesized that intraoperative dexmedetomidine use in ambulatory surgery is associated with delayed discharge from the PACU and that this is modified by surgical duration and anesthesia type. DESIGN: Retrospective cohort study. SETTING: Academic medical center. PATIENTS: 130,854 adult patients undergoing ambulatory surgery between 2008 and 2018. INTERVENTIONS: Intraoperative administration of dexmedetomidine. MEASUREMENTS: The primary outcome was PACU length of stay. In secondary and exploratory analyses, we examined dose-dependency, effect modification by duration of surgery and anesthesia type, effects of timing of dexmedetomidine administration, and PACU discharge delays. MAIN RESULTS: Dexmedetomidine was associated with a prolonged PACU length of stay (adjusted absolute difference [ADadj] 15.0 min; 95%CI 12.7-17.3; p < 0.001). This effect was dose-dependent (p-for-trend < 0.001), magnified in surgeries of less than one hour (ADadj 20.7 min; 95%CI 16.7-24.7; p < 0.001) and in patients undergoing monitored anesthesia care compared to general anesthesia (ADadj 16.8 min; 95%CI 14.1-19.6; p < 0.001). The effect was more pronounced if dexmedetomidine was administered within the last 60 min of surgery (ADadj 18.7 min; 95%CI 15.7-21.7; p < 0.001). Dexmedetomidine was associated with discharge delays due to cardiovascular complications (ORadj 2.27; 95%CI 1.59-3.24; p < 0.001) and over-sedation (ORadj 1.28; 95%CI 1.11-1.48; p < 0.001). In patients who received dexmedetomidine (n = 2901), the use of bolus doses only versus the combination of bolus and infusions, magnified the effects on PACU length of stay (ADadj 29.5 min per µg/kg; 95%CI 17.3-41.8 versus 18.1 min per µg/kg; 95%CI 11.4-24.8; p < 0.001). CONCLUSIONS: The intraoperative administration of dexmedetomidine was dose-dependently associated with a prolonged PACU length of stay. Clinicians should judiciously titrate dexmedetomidine, especially when using this long-acting drug for monitored anesthesia care for shorter procedures.

Nulla Per Os (NPO) guidelines: time to revisit?

PURPOSE OF REVIEW: Preoperative fasting guidelines are generalized to elective procedures and usually do not distinguish between the ambulatory and inpatient setting. Prevalence of aspiration is low while prolonged preoperative fasting is common clinical reality. Recently, changes in preoperative fasting guidelines have been widely discussed. RECENT FINDINGS: Rates of prolonged clear fluid fasting (>4 h) prior to surgery are reported in up to 80% of patients with mean fasting duration of up to 16 h and beyond. Prolonged fasting may result in adverse effects such as intraoperative hemodynamic instability, postoperative delirium, patient discomfort, and extended hospital length of stay. Liberal approaches allowing clear fluids up to 1 h prior to anesthesia or until premedication/call to the operating room have shown no increase in adverse events among children. Various anesthesia societies now encourage clear fluid intake up to 1 h prior to pediatric elective anesthesia. Similar reports in the adult cohort are scarce. SUMMARY: Allowing sips of water until call to the operating room may help reducing prolonged preoperative fasting and improving patient comfort while keeping a flexibility in operating room schedule. The feasibility and safety of a liberal clear fluid fasting regimen among adults undergoing elective anesthesia needs to be evaluated in future studies.

Incidence, Prediction, and Causes of Unplanned 30-Day Hospital Admission After Ambulatory Procedures.

BACKGROUND: Unanticipated hospital admission is regarded as a measure of adverse perioperative patient care. However, previously published studies for risk prediction after ambulatory procedures are sparse compared to those examining readmission after inpatient surgery. We aimed to evaluate the incidence and reasons for unplanned admission after ambulatory surgery and develop a prediction tool for preoperative risk assessment. METHODS: This retrospective cohort study included adult patients undergoing ambulatory, noncardiac procedures under anesthesia care at 2 tertiary care centers in Massachusetts, United States, between 2007 and 2017 as well as all hospitals and ambulatory surgery centers in New York State, United States, in 2014. The primary outcome was unplanned hospital admission within 30 days after discharge. We created a prediction tool (the PREdicting admission after Outpatient Procedures [PREOP] score) using stepwise backward regression analysis to predict unplanned hospital admission, based on criteria used by the Centers for Medicare & Medicaid Services, within 30 days after surgery in the Massachusetts hospital network registry. Model predictors included patient demographics, comorbidities, and procedural factors. We validated the score externally in the New York state registry. Reasons for unplanned admission were assessed. RESULTS: A total of 170,983 patients were included in the Massachusetts hospital network registry and 1,232,788 in the New York state registry. Among those, the observed rate of unplanned admission was 2.0% (3504) and 1.7% (20,622), respectively. The prediction model showed good discrimination in the training set with C-statistic of 0.77 (95% confidence interval [CI], 0.77-0.78) and satisfactory discrimination in the validation set with C-statistic of 0.71 (95% CI, 0.70-0.71). The risk of unplanned admission varied widely from 0.4% (95% CI, 0.3-0.4) among patients whose calculated PREOP scores were in the first percentile to 21.3% (95% CI, 20.0-22.5) among patients whose scores were in the 99th percentile. Predictions were well calibrated with an overall ratio of observed-to-expected events of 99.97% (95% CI, 96.3-103.6) in the training and 92.6% (95% CI, 88.8-96.4) in the external validation set. Unplanned admissions were most often related to malignancy, nonsurgical site infections, and surgical complications. CONCLUSIONS: We present an instrument for prediction of unplanned 30-day admission after ambulatory procedures under anesthesia care validated in a statewide cohort comprising academic and nonacademic hospitals as well as ambulatory surgery centers. The instrument may be useful in identifying patients at high risk for 30-day unplanned hospital admission and may be used for benchmarking hospitals, ambulatory surgery centers, and practitioners.

BOSTN Bundle Intervention for Perioperative Screening and Management of Patients With Suspected Obstructive Sleep Apnea: A Hospital Registry Study.

BACKGROUND: We developed and implemented a perioperative guideline for obstructive sleep apnea (OSA), comprising a preoperative screening tool (BOSTN) and clinical management pathways. OSA was suspected with 2 or more of the following: body mass index ≥30 kg/m, observed apnea, loud snoring, daytime tiredness, and neck circumference ≥16.5 inches in women or ≥ 17.5 inches in men. The primary objective of this study was to assess the association between high BOSTN scores and the requirement of invasive mechanical ventilation after surgery. METHODS: In this hospital registry study, 169,662 noncardiac surgical cases performed at Beth Israel Deaconess Medical Center (BIDMC), Boston, MA, between May 2008 and September 2017 were analyzed. We assessed the association between a high BOSTN Score (score ≥2) and the primary outcome of requirement of invasive mechanical ventilation within 7 days after surgery using multivariable logistic regression adjusted for patient-specific factors and case-specific surgical and anesthesiological confounders. Patients with a BOSTN Score ≥2 were assumed to have a high likelihood of suffering from OSA. Key secondary outcome was postoperative desaturation, defined as a peripheral oxygen saturation measurement <90% within 10 minutes of extubation. RESULTS: Invasive mechanical ventilation within 7 days of surgery was necessary in 3170 (2.3%) low-risk cases (BOSTN Score <2) and 664 (2.1%) high-risk cases (BOSTN Score ≥2). A score ≥2 was associated with significantly lower odds of requiring postoperative invasive ventilation (adjusted odds ratio [aOR], 0.89; 95% confidence interval [CI], 0.80-0.98; P = .017), but with an increased risk of postextubation desaturation (aOR, 1.34; 99.3% CI, 1.21-1.48; P < .001). Patients with a score ≥2 were hospitalized for an average of 3.71 days after surgery, compared to 4.27 days with a score <2 (adjusted incidence rate ratio [aIRR], 0.87; 99.3% CI, 0.84-0.91; P < .001). CONCLUSIONS: Patients at high risk of OSA required postoperative mechanical ventilation less frequently, had higher odds of postoperative desaturation, and were hospitalized for shorter periods of time.

Effects of high neuromuscular blocking agent dose on post-operative respiratory complications in infants and children.

BACKGROUND: This study evaluated the association between neuromuscular blocking agent dose and post-operative respiratory complications in infants and children. METHODS: Data from 6507 general anaesthetics provided to children aged 0-10 years undergoing surgery were analysed to examine the effects of neuromuscular blocking agent dose on post-operative respiratory complications (primary endpoint) and secondary endpoints. Confounder-adjusted analyses addressed age, surgical duration, and comorbidity burden. RESULTS: In confounder-adjusted analyses, high doses of neuromuscular blocking agents were associated with higher risk of post-operative respiratory complications (OR 2.27; 95% CI 1.12-4.59; P = .022). The effect was modified by age (P-for-interaction = .016) towards a more substantial risk in infants ≤1 year (OR 3.84; 95% CI 1.35-10.94; P = .012), by duration of surgery (P-for-interaction = .006) towards a higher difference in odds for surgeries <90 minutes (OR 4.25; 95% CI 1.19-15.18; P = .026), and by ASA physical status (P-for-interaction = .015) with a greater effect among patients with higher operative risk (ASA >1: OR 3.17; 95% CI 1.43-7.04; P = .005). Neostigmine reversal did not modify the association between neuromuscular blocking agents and post-operative respiratory complications (P-for-interaction = .38). Instrumental variable analysis confirmed that high doses of neuromuscular blocking agents were associated with post-operative respiratory complications (probit coefficient 0.25; 95% CI 0.04-0.46; P = .022), demonstrating robust results regarding concerns of unobserved confounding. CONCLUSIONS: High dose of neuromuscular blocking agents is associated with post-operative respiratory complications. We have identified subcohorts of paediatric patients who are particularly vulnerable to the respiratory side-effects of neuromuscular blocking agents: infants, paediatric patients undergoing surgeries of short duration, and those with a high ASA risk score.

Effects of laparoscopic vs open abdominal surgery on costs and hospital readmission rate and its effect modification by surgeons' case volume.

BACKGROUND: Laparoscopy provides a minimally invasive alternative to open abdominal surgery. Current data describing its association with hospital readmission and costs in relation to surgeon laparoscopic case volume is limited to smaller databases and subsets of operations. METHODS: This retrospective cohort study of 23,285 adult abdominal operations from 2007 to 2015 compares 30-day readmission rate and costs between laparoscopic and open abdominal operations and examines effect modification by surgeon laparoscopic case volume. Outcomes were all-cause hospital readmission within 30 days after discharge and index hospital admission cost. RESULTS: All-cause hospital readmission rates were significantly lower after laparoscopic abdominal operations compared with open operations (adjusted odds ratio [aOR] 0.56, 95% CI 0.46-0.69, p < 0.001) with a difference in readmission risk attributable to laparoscopic approach of - 4.0% (95% CI - 5.4 to - 2.6%) in complete-case analysis. Among surgeons with a high laparoscopic case volume, the estimated difference in readmission risk through laparoscopy was magnified (- 5.8%, 95% CI - 7.5 to - 4.1%) compared to low surgeon laparoscopic case volume (- 2.9%, 95% CI - 4.8 to -1.1%, p for interaction = 0.005). The estimated difference in costs of the index hospital admission attributable to laparoscopic approach was - $3869 (95% CI - $4200 to - $3538; adjusted incidence rate ratio 0.77, 95% CI 0.75-0.79, p < 0.001). Laparoscopy was followed by significantly lower rates of readmissions related to gastrointestinal (aOR 0.68, 95% CI 0.55-0.85, p = 0.001), wound complications (infection: aOR 0.33, 95% CI 0.23-0.47, p < 0.001; non-infectious: aOR 0.47, 95% CI 0.30-0.74, p = 0.001), and malignancy (aOR 0.68, 95% CI 0.55-0.85, p < 0.001). The findings remain robust after multiple imputation and sensitivity analyses. CONCLUSIONS: Laparoscopy versus open abdominal surgery is associated with reduced hospital readmissions related to malignancy, gastrointestinal, and wound complications. Effect modification by higher laparoscopy case volume argues for continued proliferation of laparoscopy in abdominal surgeries.

The Impact of Postoperative Intensive Care Unit Admission on Postoperative Hospital Length of Stay and Costs: A Prespecified Propensity-Matched Cohort Study.

BACKGROUND: In this prespecified cohort study, we investigated the influence of postoperative admission to the intensive care unit versus surgical ward on health care utilization among patients undergoing intermediate-risk surgery. METHODS: Of adult surgical patients who underwent general anesthesia without an absolute indication for postoperative intensive care unit admission, 3530 patients admitted postoperatively to an intensive care unit were matched to 3530 patients admitted postoperatively to a surgical ward using a propensity score based on 23 important preoperative and intraoperative predictor variables. Postoperative hospital length of stay and hospital costs were defined as primary and secondary end points, respectively. RESULTS: Among patients with low propensity for postoperative intensive care unit admission, initial triage to an intensive care unit was associated with increased postoperative length of stay (incidence rate ratio, 1.69 [95% CI, 1.59-1.79]; P < .001) and hospital costs (incidence rate ratio, 1.92 [95% CI, 1.81-2.03]; P < .001). By contrast, postoperative intensive care unit admission of patients with high propensity was associated with decreased postoperative length of stay (incidence rate ratio, 0.90 [95% CI, 0.85-0.95]; P < .001) and costs (incidence rate ratio, 0.92 [95% CI, 0.88-0.97]; P = .001). Decisions regarding postoperative intensive care unit resource utilization were influenced by individual preferences of anesthesiologists and surgeons. CONCLUSIONS: In patients with an unclear indication for postoperative critical care, intensive care unit admission may negatively impact postoperative hospital length of stay and costs. Postoperative discharge disposition varies substantially based on anesthesia and surgical provider preferences but should optimally be driven by an objective assessment of a patient's status at the end of surgery.

Patent foramen ovale and long-term risk of ischaemic stroke after surgery.

AIMS: Pre-operatively diagnosed patent foramen ovale (PFO) is associated with an increased risk of ischaemic stroke within 30 days after surgery. This study aimed to assess the PFO-attributable ischaemic stroke risk beyond the perioperative period. METHODS AND RESULTS: This observational study of adult patients without history of stroke undergoing non-cardiac surgery with general anaesthesia examined the association of PFO with ischaemic stroke 1 and 2 years after surgery using multivariable logistic regression. Of the 144 563 patients included, a total of 1642 (1.1%) and 2376 (1.6%) ischaemic strokes occurred within 1 and 2 years after surgery, 54 (4.7%) and 76 (6.6%) among patients with PFO, and 1588 (1.1%) and 2300 (1.6%) among patients without PFO, respectively. The odds of ischaemic stroke within 1 and 2 years after surgery were increased in patients with PFO: adjusted odds ratio (aOR) 2.01, 95% confidence interval (CI) 1.51-2.69; P < 0.001 and aOR 2.10, 95% CI 1.64-2.68; P < 0.001, respectively. Among patients who underwent contrast transoesophageal echocardiography, the frequency of PFO was 27%, and the increased stroke risk in patients with PFO was robust (aOR 3.80, 95% CI 1.76-8.23; P = 0.001 for year 1). The PFO-attributable risk was mitigated by post-operative prescription of combination antithrombotic therapy (odds ratio 0.41, 95% CI 0.22-0.75; P for interaction = 0.004). CONCLUSION: Patients with PFO are vulnerable to ischaemic stroke for an extended period of time after surgery. Physicians should consider implementing PFO screening protocols in patients scheduled for major non-cardiac surgery.

Association of Preoperatively Diagnosed Patent Foramen Ovale With Perioperative Ischemic Stroke.

Importance: Perioperative stroke is a major complication for patients undergoing surgery. Patent foramen ovale (PFO) represents a possible anatomical link between venous thrombosis and stroke. Objective: To determine whether a preoperatively diagnosed PFO is associated with increased risk of perioperative ischemic stroke. Design, Setting, and Participants: Retrospective cohort study from Massachusetts General Hospital and 2 affiliated community hospitals between January 1, 2007, and December 31, 2015. Participants were 182 393 consecutive adults undergoing noncardiac surgery with general anesthesia. Exposures: Preoperatively diagnosed PFO. Main Outcomes and Measures: Perioperative ischemic stroke occurring within 30 days of surgery; stroke subtype by Oxfordshire Community Stroke Project classification and stroke severity by National Institute of Health Stroke Scale (NIHSS). Results: Among the 150 198 patient cases analyzed (median [SD] age, 55 [16] years), 1540 (1.0%) had a diagnosis of PFO before surgery. A total of 850 (0.6%) ischemic strokes occurred within 30 days of surgery (49 [3.2%] among patients with PFO and 801 [0.5%] among patients without PFO). In adjusted analyses, patients with PFO had an increased risk of ischemic stroke compared with patients without PFO (odds ratio, 2.66 [95% CI, 1.96-3.63]; P < .001). The estimated risks of stroke were 5.9 for every 1000 patients with PFO and 2.2 for every 1000 patients without PFO (adjusted absolute risk difference, 0.4% [95% CI, 0.2%-0.6%). Patients with PFO also had an increased risk of large vessel territory stroke (relative risk ratio, 3.14 [95% CI, 2.21-4.48]; P < .001) and a more severe stroke-related neurologic deficit measured by NIHSS (median, 4 [interquartile range {IQR}, 2-10] vs median, 3 [IQR, 1-6] for those without PFO; P = .02). Conclusions and Relevance: Among adult patients undergoing noncardiac surgery at 3 hospitals, having a preoperatively diagnosed PFO was significantly associated with increased risk of perioperative ischemic stroke within 30 days after surgery. Further research is needed to confirm these findings and to determine whether interventions would decrease this risk.

Effects of Opioids Given to Facilitate Mechanical Ventilation on Sleep Apnea After Extubation in the Intensive Care Unit.

Study Objectives: Following extubation in the intensive care unit (ICU), upper airway (UA) edema and respiratory depressants may promote UA dysfunction. We tested the hypothesis that opioids increase the risk of sleep apnea early after extubation. Methods: Fifty-six ICU patients underwent polysomnography the night after extubation. Airflow limitation during wakefulness was identified using bedside spirometry. Correlation and ordinal regression analyses were used to quantify the effects of preextubation opioid dose on postextubation apnea-hypopnea index (AHI) and severity of sleep apnea and whether or not inspiratory airway obstruction (ratio of maximum expiratory and inspiratory airflows at 50% of vital capacity [MEF50/MIF50] ≥ 1) during wakefulness predicts airway obstruction during sleep. Data were adjusted for age, gender, body mass index, as well as a generalized propensity score balanced for APACHE II, score for preoperative prediction of obstructive sleep apnea, duration of mechanical ventilation, chronic obstructive pulmonary disease, and a procedural severity score for morbidity. Results: Sleep apnea (AHI ≥ 5) was present in 40 (71%) of the 56 patients. Morphine equivalent dose given 24 hours prior extubation predicted obstructive respiratory events during sleep (r = 0.35, p = .01) and sleep apnea (odds ratio [OR] 1.17; 95% confidence interval [CI] 1.02-1.34). Signs of inspiratory UA obstruction (MEF50/MIF50 ≥ 1) assessed by bedside spirometry were strongly associated with sleep apnea (OR 5.93; 95% CI 1.16-30.33). Conclusions: High opioid dose given 24 hours prior to extubation increases the likelihood of postextubation sleep apnea in the ICU, particularly in patients with anatomical vulnerability following extubation.

Assessing the potential for intrinsic recovery in a Collembola two-generation study: possible implementation in a tiered soil risk assessment approach for plant protection products.

Collembola are soil dwelling organisms that provide important ecosystem services within soils. To increase realism in evaluating potential effects of plant protection products a Collembola two-generation study was developed. This test assesses the potential for recovery of Collembola when exposed to plant protection products. Juvenile individuals of Folsomia candida (Willem, Ann Soc Entomol Belg 46:275-283, 1902) which hatched under conditions of exposure to a test substance in a modified OECD 232 bioassay were introduced into a second consecutive bioassay containing the same test substance aged in soil. This test system determines whether a population which was initially impacted by a substance in a 1st bioassay shows normal reproduction or survival in a 2nd bioassay after aging of the test substance in soil. An intermediate period for juvenile growth is included between the 1st and 2nd bioassay in order to reduce the control treatment variability in reproduction and mortality to fulfill the validity criteria according to the OECD 232 guideline. The Collembola two-generation study is able to differentiate between substances showing either a potential long-term risk or comprising a low risk. Comparing the results of this two generation study with data from semi-field or field studies indicates a high degree of conservatism when this test is considered within a tiered risk assessment scheme. This approach represents a valuable tool which makes the risk assessment more efficient by providing an alternative refinement option for highly conservative tier 1 Collembola risk assessment.