A Comparison of the P-POSSUM and NELA Risk Score for Patients Undergoing Emergency Laparotomy in Singapore.

BACKGROUND (AIMS, HYPOTHESES, OR OBJECTIVES): Emergency laparotomy (EL) is a high-risk surgical procedure associated with considerable morbidity and mortality around the world. A reliable risk-assessment tool that is specific to patients undergoing EL allows the early identification of high-risk patients and enables appropriate healthcare resource allocation. The objective of this study was to compare the commonly used Portsmouth-physiologic and operative severity score for the enumeration of mortality and morbidity (P-POSSUM) with the recently developed National Emergency Laparotomy Audit (NELA) score in terms of their accuracy for identifying patients at increased risk of 30-day mortality in a predominantly Asian population. METHODS: Physiological and operative data from a prospectively collected audit of adult patients undergoing EL in 2018 and 2019 across two tertiary hospitals in Singapore were used to retrospectively calculate both the P-POSSUM and NELA scores for each patient encounter. This was then compared to actual mortality rates to determine each model's accuracy and precision. RESULTS: 830 patients were included in the study with a 30-day mortality of 5.66%. The area under the receiver operating characteristics curve (AUROC) was similar for both the NELA (0.86, p < 0.001, 95% CI 0.81-0.91) and the P-POSSUM models (0.84, p < 0.001, 95% CI 0.78-0.89). While the models over-predicted mortality, overall O:E ratios showed that the NELA model performance was superior to that of P-POSSUM (0.58 [95% CI 0.43-0.77] compared to 0.34 [95% CI 0.26-0.46]). CONCLUSION: The NELA risk-prediction model accurately predicts 30-day mortality in this large cohort of patients undergoing EL and outperforms the current P-POSSUM model. We recommend that the NELA score should replace the P-POSSUM score as a model to distinguish between high- and low-risk patients undergoing EL.

Age-related changes in the location of the mandibular and mental foramen in children with Mongoloid skeletal pattern.

AIM: To observe age-related changes in the locations of mandibular foramen (MF) and mental foramen (mf) using dental panoramic tomographs (DPTs). METHODS: Ethical approval was obtained for this retrospective study. Location of MF was related to the ramus and occlusal plane, while mf to (i) erupted primary molars (ii) unerupted premolar tooth germs (iii) vertical height at the body of the mandible. RESULTS: One hundred and sixty-five DPTs were obtained from children with Mongoloid skeletal pattern. The ethnic composition was 112 Malays and 53 Chinese children (Willems dental age = 5.2-16.0 years). At the horizontal plane, MF remained constant at middle mid-quadrant of the ramus (88 %) and vertical plane; 68 % located below and 40 % above the occlusal plane. At age 9 years and above, there was a significant tendency for MF to be located at the level of occlusal plane. The most common location of mf was related to (i) erupted primary molars, mesial root of second primary molar (38 %); (ii) unerupted premolars tooth germs, between the apices of first and second premolar (44 %); and (iii) proportional vertical height to the mandible, middle third (52 %). At age 11 years and above, a significant tendency of mf to be located at the middle third of the body of mandible was observed. CONCLUSIONS: With advancing age and growth, the position of MF remained constant at the ramus with tendency to move from below to at the level of occlusal plane, while mf moved distally and inferiorly.

Effect of influenza on cardiorespiratory and all-cause mortality in Hong Kong, Singapore and Guangzhou.

1. Using a common modelling approach, mortality attributable to influenza was higher in the two subtropical cities Guangzhou and Hong Kong than in the tropical city Singapore. 2. The virus activity appeared more synchronised in subtropical cities, whereas seasonality of influenza tended to be less marked in the tropical city. 3. High temperature was associated with increased mortality after influenza infection in Hong Kong, whereas relative humidity was an effect modifier for influenza in Guangzhou. No effect modification was found for Singapore. 4. Seasonal and environmental factors probably play a more important role than socioeconomic factors in regulating seasonality and disease burden of influenza. Further studies are needed in identifying the mechanism behind the regulatory role of environmental factors.

Clinical characteristics of nosocomial norovirus outbreaks in Hong Kong.

Norovirus outbreaks occur worldwide every year and have become more frequent over the last few years. There were extensive outbreaks in Hong Kong from May to July 2006 and our aim was to describe nosocomial outbreaks from 1 May 2006 to 31 July 2006 in this retrospective observational study. A total of 38 confirmed norovirus outbreaks involving 218 patients were identified. Most of these patients were elderly with a mean age of 74.5 years (range: 3 months to 97 years); 62% of them were either totally or partially dependent for help with daily activities, 83.9% had underlying chronic medical problems and 56% had limited mobility. In all, 97.2% of individuals presented with diarrhoea and only 46.3% of them had vomiting. The median duration for diarrhoea was 3 days and the longest 24 days. The median duration of vomiting was one day and the longest 15 days. Fever occurred in one-third of all cases. Reverse transcriptase-polymerase chain reaction was positive for norovirus in 72.6% cases. We conclude that nosocomial norovirus infection often involves frail elderly patients with limited mobility and that these patients may have more prolonged symptoms.

Optimising antimicrobial prescription in hospitals by introducing an antimicrobial stewardship programme in Hong Kong: consensus statement.

OBJECTIVE: To discuss the implementation of an 'antimicrobial stewardship programme' as a means to improve the quality of antimicrobial use in a hospital setting in Hong Kong. PARTICIPANTS: Consensus working group on 'antimicrobial stewardship programme', The Scientific Committee on Infection Control, Centre for Health Protection, Department of Health, comprised 11 experts. The remit of the working group was to discuss the rationale and requirement for optimising antimicrobial prescriptions in hospitals by the introduction of an 'antimicrobial stewardship programme'. EVIDENCE: PubMed articles, national and international guidelines, and abstracts of international meetings published between January 2000 and December 2004 on programmes for improving the use of antimicrobials in hospitals. Only English medical literature was reviewed. CONSENSUS PROCESS: Data search was performed independently by three members of the working group. They met on three occasions before the meeting to discuss all collected articles. A final draft was circulated to the working group before a meeting on 3 January 2005. Five commonly asked questions about an 'antimicrobial stewardship programme' were selected for discussion by the participants. Published information on the rationale, components, outcome measures, advantages, and disadvantages of the programme was reviewed. Recent unpublished data from local studies of an 'antimicrobial stewardship programme' were also discussed. The timing, potential problems, and practical issues involved in the implementation of an 'antimicrobial stewardship programme' in Hong Kong were then considered. The consensus statement was circulated to and approved by all participants. CONCLUSION: The continuous indiscriminate and excessive use of antimicrobial agents promotes the emergence of antibiotic-resistant organisms. Antimicrobial resistance substantially raises already-rising health care costs and increases patient morbidity and mortality. Pattern of prescriptions in hospitals can be improved through the implementation of an 'antimicrobial stewardship programme'. A 'universal' and 'continuous' 'antimicrobial stewardship programme' should now be established in Hong Kong hospitals.

Seroprevalence of IgG antibodies to SARS-coronavirus in asymptomatic or subclinical population groups.

We systematically reviewed the current understanding of human population immunity against SARS-CoV in different groups, settings and geography. Our meta-analysis, which included all identified studies except those on wild animal handlers, yielded an overall seroprevalence of 0.10% [95% confidence interval (CI) 0.02-0.18]. Health-care workers and others who had close contact with SARS patients had a slightly higher degree of seroconversion (0.23%, 95% CI 0.02-0.45) compared to healthy blood donors, others from the general community or non-SARS patients recruited from the health-care setting (0.16%, 95% CI 0-0.37). When analysed by the two broad classes of testing procedures, it is clear that serial confirmatory test protocols resulted in a much lower estimate (0.050%, 95% CI 0-0.15) than single test protocols (0.20%, 95% CI 0.06-0.34). Potential epidemiological and laboratory pitfalls are also discussed as they may give rise to false or inconsistent results in measuring the seroprevalence of IgG antibodies to SARS-CoV.

Reflection on SARS precautions in a severe intellectual disabilities hospital in Hong Kong.

BACKGROUND: Hong Kong went through a battle with a new respiratory disease, severe acute respiratory syndrome (SARS), from March to June 2003. All clinical settings, including rehabilitative and infirmary setting, have actively involved in fighting against the infection. The intent of this paper was to reflect on the SARS precautionary measures that had been taken in a severe intellectual disabilities hospital in Hong Kong. METHODS: A review on six SARS precautionary measures were conducted. They were assessment of risk, formulation of operational guidelines, implementation of infection control measures, education and training of staff, conducting audits and carrying out environmental improvement work. RESULTS: Patients were at risk of getting infected from carers, visitors, volunteers, and staff and patients of general hospitals. A SARS Quarantine Unit, isolation ward, was opened to isolate patients who might have had close contact with SARS patients during a stay in a general hospital or when they returned from home leave. Undoubtedly, both staff and relatives participated in preventing the patients from being infected. No day leave and home leave was reported and the number of hospitalization in general hospital was decreased during the critical period. Three infection control audits were conducted and improvement work was carried out subsequently. CONCLUSION: The practice of grouping within a standard isolation room is recommended to continue in the future. Moreover, intensive infection control training for all staff is of highest importance to safeguard the health of both staff and patient.

Distinct genotypic distributions of cytomegalovirus (CMV) envelope glycoprotein in bone marrow and renal transplant recipients with CMV disease.

A prospective study of the spectrum of glycoprotein B (gB) and glycoprotein H (gH) genotypes of cytomegalovirus (CMV) was conducted with five categories of patients: viremic bone marrow-transplant (BMT) recipients who developed CMV disease after BMT (n = 22), viremic BMT recipients without CMV disease (n = 11), viremic renal-transplant recipients who developed CMV disease after transplantation (n = 14), viremic renal-transplant recipients without CMV disease (n = 13), and premature babies with asymptomatic congenital CMV infections (n = 13). Genotypic stability was observed because the gB and gH genotypes of multiple isolates obtained from a single patient were identical. The distribution of gH genotypes in patients of all groups studied were similar. However, there was a unique distribution of the gB genotype in the first category of patients, i.e., BMT recipients with CMV disease, which was distinct from those of all other categories (P < 0.05). CMV isolates from 54% of BMT recipients with CMV disease exhibited gB type 2, while isolates from 46, 50, 69, and 77% of the BMT recipients without CMV disease, renal-transplant recipients with and those without CMV disease, and premature babies with congenital CMV infection, respectively, were of gB type 1. An analysis of the clinical characteristics of BMT recipients with CMV disease indicated that all underwent either an allogeneic or matched, unrelated donor transplant, and half had severe acute graft-versus-host disease (grades 2 to 4). The statistically significant genotypic difference between CMV isolates from BMT recipients with and without CMV disease was not observed between isolates from renal-transplant recipients with and without CMV disease. We speculate that differences in pathogenesis in different patient groups might account for these observations. These findings would also facilitate decision making about the choice of recombinant CMV glycoprotein vaccine required to immunize transplant donors and the subsequent adoptive transfer of immunity to BMT recipients. When the source of CMV DNA required for genotyping was investigated among renal-transplant recipients, direct use of peripheral blood leukocytes was 95% effective compared to the effectiveness of cells obtained from conventional culture of peripheral blood specimens.

Vancomycin and amikacin in cell cultures for virus isolation.

Contamination of cell cultures for virus isolation has been increasingly encountered. By reviewing and changing the antimicrobials incorporated in cell culture media, we aim to control this problem. Contaminated cell culture fluids were inoculated for bacterial and fungal isolation, identification and antibacterial susceptibility testing. Based on the above results, vancomycin and amikacin were chosen to replace the penicillin and gentamicin used conventionally. Analysis was carried out on various characteristics of cell culture with respect to antimicrobial change. All contaminating Gram-positive bacteria were susceptible to vancomycin while about 80% of the Gram-negative bacteria were sensitive to amikacin. The new antimicrobial combination was not toxic to cell cultures and both antimicrobials were found to remain stable in media for over six months. The virus isolation rate was maintained after antimicrobial change while the contamination rate was reduced from nearly 10% to 1.5%. We thus conclude that vancomycin and amikacin can well replace the conventional penicillin and gentamicin to be incorporated into maintenance and transport media to control the emerging problem of viral culture contamination.