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.

How the personalities of medical students at the National University of Singapore differ from those of the local non-medical undergraduate population: a cross-sectional study

INTRODUCTION@#Integrity and willingness to contribute to society are desired traits of medical students beyond academic excellence. We investigated the personality traits of medical students at the National University of Singapore (NUS), who were about to become doctors. Personality traits were compared with a peer population of local university students.@*METHODS@#This study was conducted between October 2013 and December 2014. Year 4 medical students were administered the Revised NEO (Neuroticism-Extraversion-Openness) Personality Inventory (NEO PI-R), a 240-item Likert scale personality test. Test data was analysed by an institutional psychologist and compared to a separate sample of 377 non-medical students who were peers at the same university taking psychology as a module. Data was collated and analysed.@*RESULTS@#65 Year 4 medical students completed the NEO PI-R personality test. The personalities of Year 4 medical students at NUS differed from their peers in all domains except for openness. NUS medical students generally had less neuroticism, and were more extroverted, agreeable and conscientious than their peers.@*CONCLUSION@#Personality testing of NUS Year 4 medical students showed many of the desired traits of a doctor when compared to their peers at the same university.

An audit of preoperative fasting compliance at a major tertiary referral hospital in Singapore

<p><b>INTRODUCTION</b>To avoid the risk of pulmonary aspiration, fasting before anaesthesia is important. We postulated that the rate of noncompliance with fasting would be high in patients who were admitted on the day of surgery. Therefore, we surveyed patients in our institution to determine the rate of fasting compliance. We also examined patients' knowledge on preoperative fasting, as well as their perception of and attitudes toward preoperative fasting.</p><p><b>METHODS</b>Patients scheduled for 'day surgery' or 'same day admission surgery' under general or regional anaesthesia were surveyed over a four-week period. The patients were asked to answer an eighteen-point questionnaire on demographics, preoperative fasting and attitudes toward fasting.</p><p><b>RESULTS</b>A total of 130 patients were surveyed. 128 patients fasted before surgery, 111 patients knew that they needed to fast for at least six hours before surgery, and 121 patients believed that preoperative fasting was important, with 103 believing that preoperative fasting was necessary to avoid perioperative complications. However, patient understanding was poor, with only 44.6% of patients knowing the reason for fasting, and 10.8% of patients thinking that preoperative fasting did not include abstinence from beverages and sweets. When patients who did and did not know the reason for fasting were compared, we did not find any significant differences in age, gender or educational status.</p><p><b>CONCLUSION</b>Despite the patients' poor understanding of the reason for fasting, they were highly compliant with preoperative fasting. This is likely a result of their perception that fasting was important. However, poor understanding of the reason for fasting may lead to unintentional noncompliance.</p>

Sutureless aortic valve implantation: first experience in Asia

Age-related degenerative calcification is currently the most common cause of aortic stenosis (AS) in adults and the most frequent reason for aortic valve replacement in patients with AS. With the increased life expectancy, a large proportion of elderly patients with AS is undergoing cardiac surgery, although many are not offered conventional aortic valve replacement due to the risks involved. However, sutureless aortic valve replacement provides an alternative for this group of elderly patients. This case series reports the first experience in Asia of sutureless aortic valve implantation in seven patients at our institution.

Patient safety culture among medical students in Singapore and Hong Kong

<p><b>INTRODUCTION</b>Undergraduate education in medical schools plays an important role in promoting patient safety. Medical students from different backgrounds may have different perceptions and attitudes toward issues concerning safety. This study aimed to investigate whether patient safety cultures differed between students from two Asian countries, and if they did, to find out how they differed. This study also aimed to identify the educational needs of these students.</p><p><b>METHODS</b>A voluntary, cross-sectional and self-administered questionnaire survey was conducted on 259 students from two medical schools - one in Hong Kong and the other in Singapore. None of the students had received any formal teaching on patient safety. We used a validated survey instrument, the Attitudes to Patient Safety Questionnaire III (APSQ-III), which was designed specifically for students and covered nine key factors of patient safety culture.</p><p><b>RESULTS</b>Of the 259 students, 81 (31.3%) were from Hong Kong and 178 (68.7%) were from Singapore. The overall response rate was 66.4%. Significant differences between the two groups of students were found for two key factors - 'patient safety training', with Hong Kong students being more likely to report having received more of such training (p = 0.007); and 'error reporting confidence', which Singapore students reported having less of (p < 0.001). Both groups considered medical errors as inevitable, and that long working hours and professional incompetence were important causes of medical errors. The importance of patient involvement and team functioning were ranked relatively lower by the students.</p><p><b>CONCLUSION</b>Students from different countries with no prior teaching on patient safety may differ in their baseline patient safety cultures and educational needs. Our findings serve as a reference for future longitudinal studies on the effects of different teaching and healthcare development programmes.</p>

Anatomical variations of the internal jugular vein: implications for successful cannulation and risk of carotid artery puncture

<p><b>INTRODUCTION</b>Complications occur in over 15% of central venous cannulations, often a result of anatomical variations. This study aimed to determine the anatomical variations of the internal jugular vein (IJV), demonstrate the likely success of cannulation and assess the risk of carotid artery (CA) injury when catheterising the IJV using the external landmarks technique at various degrees of head rotation in the local population.</p><p><b>METHODS</b>100 elective cardiac surgical patients were prospectively enrolled. Simulated catheterisations were performed with patients placed in the Trendelenburg position. The standard landmark technique was used to identify anatomy. Simulations were done at six different degrees of rotation of the head: 0°, 30° and 60° for both right and left IJVs. Difficult catheterisation was defined as an IJV diameter < 7 mm.</p><p><b>RESULTS</b>There was no thrombosed or absent IJV in any patient. Catheterisation was potentially difficult in 15% of patients at 30° head rotation and more difficult for the left IJV than the right (20% vs. 10%; p < 0.05). The simulated needle hit the IJV in 82% of the attempts, but the needle was in the middle 80% of the vein only 70% of the time. Neck rotation increased the degree of overlap of the CA relative to the IJV from 20%-30% to 50%.</p><p><b>CONCLUSION</b>Anatomical variations play a significant role in determining the success of IJV catheterisation as well as the incidence of catheterisation-associated complications. This study emphasises the importance of using ultrasonography to guide IJV catheterisation, even in patients with seemingly normal neck anatomy.</p>

The impact of experiential learning on NUS medical students: our experience with task trainers and human-patient simulation

<p><b>INTRODUCTION</b>Experiential learning is one of the key methods for effective teaching of medical students. The use of simulation is ideal to achieve this goal. Simulation training allows the learner to be actively involved, and provides realism, self-direction, feedback and practice. We present 2 pilot projects in which the efficacy of experiential learning with simulation is demonstrated.</p><p><b>MATERIALS AND METHODS</b>In the first project, groups of 4 to 6 fourth-year medical students were exposed to common crisis scenarios. Each student took turns to individually handle the situation (in the hot seat), while the rest of the group watched "live" via video-link. A group debrief was done after the completion of all scenarios and learning points were emphasized. A test was conducted shortly after, and the student who managed the same scenario in the hot seat earlier was compared to the rest of the group with respect to crisis recognition, management and diagnosis. In the second project, 36 fourth-year medical students were assigned to learn endotracheal intubation through a directed or experiential method. Students were recalled after 3 months and tested on 4 major categories: preparation, technique, success and ventilation.</p><p><b>RESULTS</b>Students in the hot seat tended to perform better (72% vs. 64%), and were more likely to be the highest scoring student within their group; although this did not reach statistical significance. For the intubation study, students in the experiential group had a higher success rate at 3 months (78% vs. 41%).</p><p><b>CONCLUSIONS</b>Experiential teaching methods with simulation result in better learning of crisis management and endotracheal intubation.</p>