Risk factors of post-anaesthesia care unit delirium in patients undergoing non-cardiac surgery in Singapore.

Introduction: Post-anaesthesia care unit (PACU) delirium affects 5%-45% of patients after surgery and is associated with postoperative delirium and increased mortality. Up to 40% of PACU delirium is preventable, but it remains under-recognised due to a lack of awareness of its diagnosis. The nursing delirium screening scale (Nu-DESC) has been validated for diagnosing PACU delirium, but is not routinely used locally. This study aimed to use Nu-DESC to establish the incidence and risk factors of PACU delirium in patients undergoing non-cardiac surgery in the surgical population. Methods: We conducted an audit of eligible patients undergoing major surgery in three public hospitals in Singapore over 1 week. Patients were assessed for delirium 30-60 min following their arrival in PACU using Nu-DESC, with a total score of ≥2 indicative of delirium. Results: A total of 478 patients were assessed. The overall incidence rate of PACU delirium was 18/478 (3.8%), and the incidence was 9/146 (6.2%) in patients aged > 65 years. Post-anaesthesia care unit delirium was more common in females, patients with malignancy and those who underwent longer operations. Logistic regression analysis showed that the use of bispectral index (P < 0.001) and the presence of malignancy (P < 0.001) were significantly associated with a higher incidence of PACU delirium. Conclusion: In this first local study, the incidence of PACU delirium was 3.8%, increasing to 6.2% in those aged > 65 years. Understanding these risk factors will form the basis for which protocols can be established to optimise resource management and prevent long-term morbidities and mortality in PACU delirium.

Incidence and risk factors of delirium in post-anaesthesia care unit.

INTRODUCTION: Post-anaesthesia care unit (PACU) delirium is a potentially preventable condition that results in a significant long-term effect. In a multicentre prospective cohort study, we investigate the incidence and risk factors of postoperative delirium in elderly patients undergoing major non-cardiac surgery. METHODS: Patients were consented and recruited from 4 major hospitals in Singapore. Research ethics approval was obtained. Patients older than 65 years undergoing non-cardiac surgery >2 hours were recruited. Baseline perioperative data were collected. Preoperative baseline cognition was obtained. Patients were assessed in the post-anaesthesia care unit for delirium 30-60 minutes after arrival using the Nursing Delirium Screening Scale (Nu-DESC). RESULTS: Ninety-eight patients completed the study. Eleven patients (11.2%) had postoperative delirium. Patients who had PACU delirium were older (74.6±3.2 versus 70.6±4.4 years, P=0.005). Univariate analysis showed those who had PACU delirium are more likely to be ASA 3 (63.6% vs 31.0%, P=0.019), had estimated glomerular filtration rate (eGFR) of >60mL/min/1.73m2 (36.4% vs 10.6%, P=0.013), higher HbA1C value (7.8±1.2 vs 6.6±0.9, P=0.011), raised random blood glucose (10.0±5.0mmol/L vs 6.5±2.4mmol/L, P=0.0066), and moderate-severe depression (18.2% vs 1.1%, P=0.033). They are more likely to stay longer in hospital (median 8 days [range 4-18] vs 4 days [range 2-8], P=0.049). Raised random blood glucose is independently associated with increased PACU delirium on multivariate analysis.

The Difference between Computed Tomography and Magnetic Resonance Imaging Measurements of Tibial Tubercle-Trochlear Groove Distance for Patients with or without Patellofemoral Instability: A Systematic Review and Meta-analysis.

The tibial tubercle-trochlear groove (TT-TG) distance was originally described for computed tomography (CT) but has recently been used on magnetic resonance imaging (MRI) without sufficient evidence demonstrating its validity on MRI. The current review aims to evaluate (1) whether there is a difference in the TT-TG distances measured using CT and MRI, (2) whether both the TT-TG distances measured using CT and MRI could be used to differentiate between patients with or without patellofemoral instability, and (3) whether the same threshold of 15 to 20 mm can be applied for both TT-TG distances measured using CT and MRI. The review was conducted using the preferred reporting items for systematic reviews and meta-analyses (PRSIMA) guidelines. All studies that compared TT-TG distances either (1) between CT and MRI or (2) between patients with and without patellofemoral instability were included. A total of 23 publications were included in the review. These included a total of 3,040 patients. All publications reported the TT-TG distance to be greater in patients with patellofemoral instability as compared to those without patellofemoral instability. This difference was noted for both TT-TG distances measured on CT and on MRI. All publications also reported the TT-TG distance measured on CT to be greater than that measured on MRI (mean difference [MD] = 1.79 mm; 95% confidence interval [CI]: 0.91-2.68). Pooling of the studies revealed that the mean TT-TG distance for the control group was 12.85 mm (95% CI: 11.71-14.01) while the mean TT-TG distance for patients with patellofemoral instability was 18.33 mm (95% CI: 17.04-19.62) when measured on CT. When measured on MRI, the mean TT-TG distance for the control group was 9.83 mm (95% CI: 9.11-10.54), while the mean TT-TG distance for patients with patellofemoral instability was 15.33 mm (95% CI: 14.24-16.42). Both the TTTG distances measured on CT and MRI could be used to differentiate between patients with and without patellofemoral instability. Patients with patellofemoral instability had significantly greater TT-TG distances than those without. However, the TT-TG distances measured on CT were significantly greater than that measured on MRI. Different cut-off values should, therefore, be used for TT-TG distances measured on CT and on MRI in the determination of normal versus abnormal values. Pooling of all the patients included in the review then suggest for 15.5 ± 1.5 mm to be used as the cut off for TT-TG distance measured on CT, and for 12.5 ± 2 mm to be used as the cut-off for TT-TG distance measured on MRI. The Level of evidence for this study is IV.

The Difference between Cartilaginous and Bony Sulcus Angles for Patients with or without Patellofemoral Instability: A Systematic Review and Meta-Analysis.

The cartilaginous sulcus angle and bony sulcus angle have been widely used to evaluate trochlea dysplasia. The current review aims to evaluate (1) whether there is a difference in measurement for cartilaginous and bony sulcus angles, (2) whether both the cartilaginous and bony sulcus angles could be used to differentiate between patients with or without trochlear dysplasia, and (3) whether the same cut-off of 145 degrees, originally used for radiographs, can be applied for the cartilaginous and bony sulcus angles measured on CT and MRI. The review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRSIMA) guidelines. A total of 11 publications with 1204 patients were included. All publications reported the sulcus angle to be greater in patients with patellofemoral instability. All publications reported the cartilaginous sulcus angle to be greater than the bony sulcus angle (MD 7.27 degrees; 95% CI: 5.67 - 8.87). The mean cartilaginous sulcus angle for the control group was 141.83 degrees (95% CI: 139.90 - 143.76) while the mean cartilaginous sulcus angle for patients with patellofemoral instability was 156.24 degrees (95% CI: 153.71 - 158.77). The mean bony sulcus angle for the control group was noted to be 133.69 degrees (95% CI: 131.23 - 136.15) while the mean bony sulcus angle for patients with patellofemoral instability was 148.42 (95% CI: 144.02 - 152.82). Both the cartilaginous and bony sulcus angles measured on CT and MRI could therefore be used to differentiate between patients with and without trochlear dysplasia. However, the cartilaginous sulcus angles are significantly higher than that of bony sulcus angles. Different cut off values should therefore be used.

Impact of Knowledge and Attitudes on Lifestyle Practices in Preventing Type 2 Diabetes Mellitus.

INTRODUCTION: Diabetes mellitus is a major public health issue in Singapore. To shape healthcare policies for the primary prevention of diabetes, it is crucial to understand Singaporeans' knowledge, attitudes and practices related to diabetes and its prevention. This study aimed to assess the knowledge, attitudes and lifestyles of individuals without diabetes. MATERIALS AND METHODS: A cross-sectional household survey was performed between 31 January to 3 February 2019 to examine knowledge, attitudes and practices related to diabetes. Inclusion criteria of the participants included: 1) Singaporeans/permanent residents, 2) between 30 to 64 years old, and 3) who did not have a diagnosis of diabetes. Logistic and linear regression models were used to analyse the association of knowledge and attitudes with physical activity and diet habits, respectively. RESULTS: Among 806 participants, 72.2% did not meet the Health Promotion Board's physical activity recommendation. Physical activity was associated with better diabetes knowledge (odds ratio [OR] 5.38, 95% confidence interval [CI] = 1.65-17.53, P = 0.049), stronger beliefs in diabetes prevention (OR 3.36, 95% CI = 1.02-11.12, P = 0.047) and lower levels of worry about diabetes (OR 0.41, 95% CI 0.17-1.00, P = 0.049). Neither knowledge nor beliefs or worries about diabetes was associated with diet. CONCLUSION: There is a need to reinforce the importance of physical activity and healthy diet in preventing diabetes. Although improving the knowledge level of diabetes may increase physical activity of the population, it is unlikely to improve dietary choices without effective behavior change interventions.

Impact of bariatric surgery on serum uric acid levels and the incidence of gout-A meta-analysis.

Gout is characterized by high serum uric acid (SUA) levels and arthritis. It is associated with obesity and metabolic syndrome. Bariatric surgery has been associated with decreased SUA levels and overall gout incidence. This meta-analysis aims to summarize the current evidence on bariatric surgery, gout and SUA levels. A literature review was performed on papers published from 2000 up till December 2018. Original studies investigating the impact of bariatric surgery on SUA levels or gout incidence were evaluated. Twenty studies with a total of 5,233 patients were analysed. Majority (n=14) had a follow-up duration of at least 12 months. The mean preoperative body mass index (BMI) was 45.2kg m-2 . The mean preoperative SUA level was 6.5mg dL-1 . Subgroup analysis demonstrated a mean decrease in SUA levels (-0.73mg dL-1 ) from the third postoperative month onwards, which was sustained until the third postoperative year (-1.91mg dL-1 ). There was a rise in SUA levels in the first post-operative month. Meta-regression analyses demonstrated a proportionate linear relationship between the change in BMI and SUA levels. Post-bariatric surgery weight loss is associated with reduced SUA levels and decreased incidence of gout attacks. However, this is only evident from the third post-operative month onwards.

Three-dimensional shape measurement using a structured light system with dual projectors.

This paper introduces a structured light system with two projectors and one camera for three-dimensional (3D) shape measurement to alleviate problems created by a single projector such as the shadow problem. In particular, we developed (1) a system calibration framework that can accurately calibrate each such camera-projector system; (2) a residual error correction method based on the system error function; and (3) a data fusion method utilizing the angle between the projection direction and surface normal. Experimental results demonstrate that the proposed dual-projector structured light system improves the measurement accuracy besides extending the measurement range of a single projector system.

Whisker array functional representation in rat barrel cortex: transcendence of one-to-one topography and its underlying mechanism.

The one-to-one relationship between whiskers, barrels, and barrel columns described for rat barrel cortex demonstrates that the organization of cortical function adheres to topographical and columnar principles. Supporting evidence is typically based on a single or few whiskers being stimulated, although behaving rats rely on the use of all their whiskers. Less is known about the cortical response when many whiskers are stimulated. Here, we use intrinsic signal optical imaging and supra- and sub-threshold electrophysiology recordings to map and characterize the cortical response to an array of all large whiskers. The cortical response was found to possess a single peak located centrally within a large activation spread, thereby no longer conveying information about the individual identities of the stimulated whiskers (e.g., many local peaks). Using modeling and pharmacological manipulations, we determined that this single central peak, plus other salient properties, can be predicted by and depends on large cortical activation spreads evoked by individual whisker stimulation. Compared to single whisker stimulation, the peak magnitude was comparable in strength and the response area was 2.6-fold larger, with both exhibiting a reduction in variability that was particularly pronounced (3.8x) for the peak magnitude. Findings extended to a different collection (subset) of whiskers. Our results indicate the rat barrel cortex response to multi-site stimulation transcends one-to-one topography to culminate in a large activation spread with a single central peak, and offer a potential neurobiological mechanism for the psychophysical phenomenon of multi-site stimulation being perceived as though a single, central site has been stimulated.

Pressure support ventilation vs spontaneous ventilation via ProSeal™ laryngeal mask airway in pediatric patients undergoing ambulatory surgery: a randomized controlled trial.

AIM: To investigate the advantages of using pressure support ventilation (PSV) vs spontaneous ventilation via ProSeal™ laryngeal mask airway in children undergoing ambulatory surgery. BACKGROUND: In our ambulatory surgical unit, the use of unassisted spontaneous breathing via laryngeal mask airway is a common anesthetic technique during general anesthesia. However, this may be associated with inadequate ventilation. PSV is a ventilatory mode that is synchronized with the patient's respiratory effort and may improve gaseous exchange under general anesthesia. MATERIALS AND METHODS: After the approval from the ethics committee, a randomized controlled trial involving 24 pediatric patients was conducted in our ambulatory surgical unit. They were randomized into two groups, namely Group PSV (receiving PSV) and Group SV (unassisted spontaneous ventilation). Outcome measures included intraoperative respiratory and hemodynamic parameters as well as recovery room data. RESULTS: There were no significant differences in baseline characteristics between the two groups. Patients in Group PSV had lower ETCO(2) (42.8 ± 5.8 vs 50.4 ± 4.0, P = 0.001) and higher expiratory tidal volume per kg bodyweight (8.3 ± 1.8 ml kg(-1) vs 5.8 ± 0.8 ml kg(-1), P = 0.001) compared with patients in Group SV. There were no significant differences in other respiratory and hemodynamic parameters or recovery room data between the two groups. CONCLUSION: Pressure support ventilation via ProSeal™ laryngeal mask airway during general anesthesia improves ventilation in pediatric patients undergoing ambulatory surgery. However, this did not translate to a difference in clinical outcome among our study patients.