Objective: The concept of "breaks" in sedentary behavior has emerged as a potential modifier of detrimental effects on adiposity caused by sedentary behavior. The existing research investigating the relationship between breaks in sedentary behavior with adiposity and cardiometabolic health in adults was systematically reviewed and quantitatively synthesized by this study. Methods: Observational and experimental studies that examined the relationships between the frequency of interruptions of sedentary behavior and markers of adiposity and cardiometabolic health in adults were identified by a systematic search of the literature. A meta-analysis was conducted by using the inverse variance method for experimental trials and a Bayesian posterior probability of existence of an association between breaks with adiposity and cardiometabolic markers for observational studies. Results: It was revealed by the pooled results from nine experimental studies that breaks in sedentary periods of at least light intensity may have a positive effect on glycemia but not on lipidemia for adults. It is unclear whether this effect is independent of total sitting time. However, the 10 identified observational studies showed an association with breaks, which was independent of total sedentary time, but only for obesity metrics. Conclusions: The theory that interrupting bouts of sedentary behavior with light-intensity activity might help control adiposity and postprandial glycemia was supported by the evidence. Further investigations with better methods of measuring sedentary behavior patterns and improved study designs are necessary to confirm this preliminary evidence.

IMPORTANCE An intraoperative higher level of positive end-expiratory positive pressure (PEEP) with alveolar recruitment maneuvers improves respiratory function in obese patients undergoing surgery, but the effect on clinical outcomes is uncertain. OBJECTIVE To determine whether a higher level of PEEP with alveolar recruitment maneuvers decreases postoperative pulmonary complications in obese patients undergoing surgery compared with a lower level of PEEP. DESIGN, SETTING, AND PARTICIPANTS Randomized clinical trial of 2013 adults with body mass indices of 35 or greater and substantial risk for postoperative pulmonary complications who were undergoing noncardiac, nonneurological surgery under general anesthesia. The trial was conducted at 77 sites in 23 countries from July 2014-February 2018; final follow-up: May 2018. INTERVENTIONS Patients were randomized to the high level of PEEP group (n = 989), consisting of a PEEP level of 12 cm H 2 O with alveolar recruitment maneuvers (a stepwise increase of tidal volume and eventually PEEP) or to the low level of PEEP group (n = 987), consisting of a PEEP level of 4 cm H 2 O. All patients received volume-controlled ventilation with a tidal volume of 7 mL/kg of predicted body weight. MAIN OUTCOMES AND MEASURES The primary outcome was a composite of pulmonary complications within the first 5 postoperative days, including respiratory failure, acute respiratory distress syndrome, bronchospasm, new pulmonary infiltrates, pulmonary infection, aspiration pneumonitis, pleural effusion, atelectasis, cardiopulmonary edema, and pneumothorax. Among the 9 prespecified secondary outcomes, 3 were intraoperative complications, including hypoxemia (oxygen desaturation with SpO 2 Յ92% for >1 minute). RESULTS Among 2013 adults who were randomized, 1976 (98.2%) completed the trial (mean age, 48.8 years; 1381 [69.9%] women; 1778 [90.1%] underwent abdominal operations). In the intention-to-treat analysis, the primary outcome occurred in 211 of 989 patients (21.3%) in the high level of PEEP group compared with 233 of 987 patients (23.6%) in the low level of PEEP group (difference, −2.3% [95% CI, −5.9% to 1.4%]; risk ratio, 0.93 [95% CI, 0.83 to 1.04]; P = .23). Among the 9 prespecified secondary outcomes, 6 were not significantly different between the high and low level of PEEP groups, and 3 were significantly different, including fewer patients with hypoxemia (5.0% in the high level of PEEP group vs 13.6% in the low level of PEEP group; difference, −8.6% [95% CI, −11.1% to 6.1%]; P < .001). CONCLUSIONS AND RELEVANCE Among obese patients undergoing surgery under general anesthesia, an intraoperative mechanical ventilation strategy with a higher level of PEEP and alveolar recruitment maneuvers, compared with a strategy with a lower level of PEEP, did not reduce postoperative pulmonary complications.

OBJECTIVE:To determine the levels and patterns of physical activity in a sample of obese (Z99th percentile body mass index (BMI)) and nonobese (o99th percentile BMI) children. DESIGN: Cross-sectional study. SETTING: Children were recruited from schools in Bristol and from the childhood obesity clinic, Bristol Royal Hospital for Children. Children were instructed in the use of the accelerometer either while at school or in the clinic, and wore the instrument while carrying out their normal daily activities for 7 days. PARTICIPANTS: A total of133 children (mean age 10.570.8 y). In all 11 (16.9%) of the 65 girls and 14 (20.6%) of the 68 boys were classified as obese (above the 99th percentile for BMI and corresponding to projected adult BMI of 30). MAIN OUTCOME MEASURES: Objectively measured physical activity volume, intensity and pattern. RESULTS: Obese children were significantly less physically active overall than their nonobese counterparts (31 844713 200 vs 41 844710 430 counts/h; 95% confidence interval 4407 to 15592; P ¼ 0.001). Similarly the obese children spent less time in physical activity of moderate or greater intensity than the nonobese children (9.973.9 vs 12.974.2 min/h; 95% confidence interval 1.15 to 4.80; P ¼ 0.002). Hourly patterns of activity indicated a tendency in obese children to be less active than nonobese children at times when activity was more likely to be determined by free choice, particularly outside of school time. CONCLUSIONS: Obese children demonstrated patterns of physical activity that may have contributed to and are likely to sustain their obesity. Minute-by-minute accelerometry is a valuable tool to investigate physical activity patterns in obese children. It can identify periods when intervention to increase activity may be most appropriate and provide an evidence base for specific exercise prescription in primary and secondary care.

Gabapentin has no effect on immediate pain after abdominal hysterectomy but decreases pain 1 month postoperatively.