Utilisation of emergency medical service among Singapore patients presenting with ST-segment elevation myocardial infarction: prevalence and impact on ischaemic time.

BACKGROUND: Previous studies in Western countries found that the emergency medical service (EMS) was under-used in patients with myocardial infarction. AIM: We sought to determine the prevalence of immediate EMS utilisation among Singapore patients presenting with ST-segment elevation myocardial infarction (STEMI), and correlated the use of the EMS with the symptom-to-balloon and door-to-balloon times. METHODS: We studied 252 patients admitted with STEMI to our institution from August 2008 to September 2009. Information regarding demographic characteristics, whether EMS was used, reperfusion procedural details and mortality rates were collected prospectively. RESULTS: Among the recruited patients, 89 (35.3%) used the EMS (EMS group) and 163 (64.7%) did not use the EMS (non-EMS group). In the latter group, 98 (60.1%) arrived at our institution through their own transport, 56 (34.4%) first consulted general practitioners, and 9 (5.5%) initially consulted another hospital without acute medical services. Among the 245 (out of 252, 97.2%) patients who received percutaneous coronary intervention (PCI), the EMS group was more likely to undergo primary PCI (P= 0.003) while the non-EMS group was more likely to undergo non-urgent PCI (P= 0.002). In patients who underwent primary PCI, the EMS group had a shorter symptom-to-balloon time (average difference 81.6 min, P= 0.002). The door-to-balloon time was similar for both groups. CONCLUSION: Despite the availability of a centralised EMS, 64.7% of patients with STEMI did not contact EMS at presentation. These patients were less likely to receive primary PCI and had a significantly longer symptom-to-balloon time.

Probiotic supplementation in the first 6 months of life in at risk Asian infants--effects on eczema and atopic sensitization at the age of 1 year.

BACKGROUND: The role of probiotics in allergy prevention remains uncertain but has been shown in some studies to have a possible protective effect on eczema. OBJECTIVE: We aimed to assess the effect of probiotic supplementation in the first 6 months of life on eczema and allergic sensitization at 1 year of age in Asian infants at risk of allergic disease. METHODS: A double-blind, placebo-controlled randomized clinical trial involving 253 infants with a family history of allergic disease was carried out. Infants received at least 60 mL of commercially available cow's milk formula with or without probiotic supplementation [Bifidobacterium longum (BL999) 1 x 10(7) colony forming unit (CFU)/g and Lactobacillus rhamnosus (LPR) 2 x 10(7) CFU/g] daily for the first 6 months. Clinical evaluation was performed at 1, 3, 6 and 12 months of age, with serum total IgE measurement and skin prick tests conducted at the 12-month visit. The primary and secondary end-points were eczema and allergen sensitization, respectively. RESULTS: The incidence of eczema in the probiotic (22%) group was similar to that in the placebo group (25%) (P=0.53). The median Scoring Atopic Dermatitis score at 12 months was 17.10 (9.74) in the probiotic group and 11.60 (8.40) in the placebo group (P=0.17). The prevalence of allergen sensitization showed no difference (probiotic=24% vs. placebo=19%, P=0.26). The total IgE geometric mean (95% confidence interval) was 18.76 (12.54-24.98) kU/L in the probiotic group and 23.13 (16.01-30.24) kU/L in the placebo group (P=0.15). Atopic eczema (with sensitization) in the probiotic (7.3%) group was comparable to the placebo group (5.8%) (P=0.86). CONCLUSION: Early life administration of a cow's milk formula supplemented with probiotics showed no effect on prevention of eczema or allergen sensitization in the first year of life in Asian infants at risk of allergic disease. Further work is needed to determine whether timing of supplementation, dose and probiotic strain are important considerations.

Hand-assisted laparoscopic colectomy versus standard laparoscopic colectomy: a cost analysis.

OBJECTIVE: There is a relative dearth of literature comparing hand-assisted (HALC) to standard (SLC) laparoscopic colectomies. HALC seems beneficial in terms of shorter operative times and lower conversion rates, but this is counterbalanced by a greater inflammatory response, larger incisions and higher direct costs. Nevertheless, these results are not consistent throughout existing studies and there are to date no detailed cost comparisons. Our hypothesis was that HALC would not incur significantly higher institutional costs compared with standard laparoscopic techniques. METHOD: Patients undergoing either SLC or HALC between August 2004 and September 2006 were retrospectively reviewed. All patients were managed using a standard protocol. Outcomes assessed included operative times, conversion rates, pain scores, time to resolution of ileus, length of stay and complications. Total costs were calculated from the day of surgery. Statistical analyses included chi(2), Fisher's exact test, the Mann-Whitney U-test or nonparametric bootstrapping method. RESULTS: Seventy-three patients underwent SLC while 101 had HALC. Demographics and indications for surgery in both groups were similar; the majority were performed for colorectal cancers. Operative times were shorter (147.5 vs 172.5 min, P < 0.05) and complication rates lower (28.7%vs 45.2%, P < 0.025) for HALC. There was no significant difference in the other clinical outcomes. Operative costs and cost of consumables were higher for HALC (US$4024.2 vs US$3568.1, P = 0.01 and US$1724.7 vs US$1302.7, P < 0.001, respectively). However, total costs were not significantly different (HALC US$8999.8, SLC US$7910.7, P = 0.11). CONCLUSION: Institutional costs are not significantly higher for HALC compared with SLC.

Evaluation of playground injuries based on ICD, E codes, international classification of external cause of injury codes (ICECI), and abbreviated injury scale coding systems.

The survey is aimed to describe the epidemiology of playground related injuries in Singapore based on the ICD-9, AIS/ ISS and PTS scoring systems, and mechanisms and causes of such injuries according to E codes and ICECI codes. A cross-sectional questionnaire survey examined children (< 16 years old), who sought treatment for or died of unintentional injuries in the ED of three hospitals, two primary care centers and the sole Forensic Medicine Department of Singapore. A data dictionary was compiled using guidelines from CDC/WHO. The ISS, AIS and PTS, ICD-9, ICECI v1 and E codes were used to describe the details of the injuries. 19,094 childhood injuries were recorded in the database, of which 1617 were playground injuries (8.5%). The injured children (mean age=6.8 years, SD 2.9 years) were predo-minantly male (M:F ratio = 1.71:1). Falls were the most frequent in-juries (70.7%) using ICECI. 25.0% of injuries involved radial and ulnar fractures (ICD-9 code). 99.4% of these injuries were minor, with PTS scores of 9-12. Children aged 6-10 years, were prone to upper limb injuries (71.1%) based on AIS. The use of international coding systems in injury surveillance facilitated standardisation of description and comparison of playground injuries.

Antecedent risk factors and their control in young patients with a first myocardial infarction.

INTRODUCTION: Identifying and controlling cardiovascular risk factors at an early age may prevent cases of young myocardial infarction (MI). We studied age-related differences in the cumulative incidence of risk factors and the adequacy of primary prevention by surveying 1,556 patients with a first MI admitted to a tertiary hospital in Singapore. METHODS: This is a single centre registry-based study on patients admitted with a first MI to a tertiary hospital in Singapore. We stratified the cohort into younger (45 years of age and younger) and older (older than 45 years of age) groups. The presence of five risk factors, namely: hypertension, diabetes mellitus (DM), smoking, a family history of premature MI, and hyperlipidaemia, was assessed at the point of care by interview and prior medical records when obtainable. We also determined by the same methods, if these patients were receiving active treatment for DM, hypertension or hyperlipidaemia prior to their first MI. Lipid levels were measured within 24 hours of admission. RESULTS: 96 percent of patients 45 years and younger and 92 percent of those older than 45 years had at least one antecedent risk factor. The 45 years and younger age group had a higher incidence of untreated hypertension (odds ratio 2.99, 95 percent confidence interval 2.00-4.46, p-value is less than 0.001) and hyperlipidaemia (odds ratio 1.71, 95 percent confidence interval 1.20 - 2.43, p-value is equal to 0.002). CONCLUSION: A majority of young patients with a first MI have at least one identifiable antecedent risk factor. There is significant undertreatment of hypertension and hyperlipidaemia in this age group.

Locally advanced and metastatic breast cancer in a tertiary hospital.

INTRODUCTION: The breast cancer incidence among Singapore women has risen through the years and is now the highest in Asia. Despite efforts to promote a greater awareness of breast cancer among the public, a significant number of patients still present with locally advanced or metastatic breast cancer. Our study aims to evaluate the clinical and pathological characteristics between patients presenting with locally advanced (LABC) and metastatic breast cancer (MBC) and those presenting with early breast cancer (EBC), to identify factors that predict for advanced disease. MATERIALS AND METHODS: We reviewed 622 patients who were newly diagnosed with invasive breast cancer in our department over a 4-year period from January 2000 to December 2003. Patient and tumour characteristics including age, parity, family history, tumour size and histology, grade and hormonal receptor status were analysed. Comparisons were made between those with EBC and those with LABC and MBC, as well as between Malay women and women of other ethnic groups. RESULTS: One hundred and thirty-four patients (21.5%) presented with either LABC or MBC. Adjusted analysis found that these patients were older and more likely to be nulliparous than those with EBC. Older patients tend to have larger tumours, but otherwise, age and parity did not correlate with tumour histology, grade or hormonal status. It was noted that Malay women, who were more likely to present with LABC or MBC, were more likely to have oestrogen receptor- and progesterone receptor-negative tumours. CONCLUSIONS: Older women and those who were nulliparous were found more likely to present with LABC and MBC. However, age and parity did not appear to be related to tumour histology, grade and hormonal status. Given that tumour size and stage have the greatest impact on overall survival, efforts to raise public awareness of the benefits of early detection and treatment should be continued, and possibly directed towards these groups of women who appear to be at an increased risk of presenting late.

HLA-system in Chinese children with insulin-dependent diabetes mellitus: a strong association with DR3.

We studied the distribution of HLA-A, B, and DR and MT1, MT2, MT3 genotypes in all 20 Chinese children with insulin-dependent diabetes mellitus (IDDM) attending the four government pediatric units in Singapore. We found an increase in HLA BW22 but the corrected probability value was not statistically significant. AW33 and B17 were observed in 50% and 55% of IDDM children, respectively, compared with 11% and 13% of normal controls, respectively. The values for AW33 were as follows: corrected P = 0.00094 and relative risk (RR) = 8.17; for B17 they were corrected P = 0.001 and RR = 7.55. In addition, the frequency of DR3 was 50% in IDDM children compared with 14% of normal controls (corrected P = 0.0019, RR = 6.20). AW33, B17, and DR3 are in linkage disequilibrium in our normal Chinese population. All ten patients who were positive for DR3 also had B17. The frequency of DR4 was not increased, and there were no protection IDDM related antigens found. These differences compared with the results in Western populations may contribute to the relative rarity of IDDM among Chinese children.

Role of glucose homeostatic mechanisms in viral infections.

Though normoglycaemia is thought to indicate adequacy of cellular glucose content, ketoacidosis occurs in viral infections even in the presence of normo- and hyperglycaemia. These wide variations in glucose concentrations may reflect the patients' adaptive abilities in situations where glucose transport is impaired by viruses. Hypoglycaemia would suggest poor adaptation and hyperglycaemia good adaptation. Increased free fatty acid (FFA) concentrations and enzyme activity are probable adaptive mechanisms. If so, they should decrease with hyperglycaemia-producing infusions. Profiles of glucose, FFA, enzymes, and fever over 19 days in 24 children with viral infections are reported. On admission 87.5% were normo- or hyperglycaemic with increased FFA, AST, LDH, and fever (P less than 0.005) when compared with values 19 days later. With infusions that produced hyperglycaemia, there was clinical recovery with a decrease in FFA and enzyme activity. The hyperglycaemia observed in 56.5% therefore points to glucose homeostatic mechanisms being geared to maintain the intracellular milieu. Hence normoglycaemia does not always indicate cellular glucose adequacy.

Relapse markers in childhood thyrotoxicosis.

Childhood thyrotoxicosis is not an uncommon illness, but there is a considerable relapse rate in these patients on medical treatment. An attempt is made in this study to identify those markers that are predictive of a tendency to relapse in childhood thyrotoxicosis. A total of 32 patients with Graves disease were included in the study. Several features were correlated with a tendency to relapse. Of these features, sex, family history, and antibody status were not significantly correlated to relapse. However, of 17 patients with goiter size two times normal or larger, 16 relapsed in comparison with seven relapses of 15 patients with goiter size less than two times normal (p = 0.0039). Of eight patients without ophthalmopathy, only two relapsed, while 21 patients of 24 patients with ophthalmopathy, relapsed (p = 0.002). Of 13 patients with serum thyroxine levels below 20 mcg/dl, six relapsed; of the 19 patients with serum thyroxine levels above 20 mcg/dl, 17 relapsed (p = 0.039). Among 24 patients with a previous relapse, only one achieved a remission with a second course of treatment. The remaining 23 patients had recurrent relapses. Hence it was found that goiter size, presence of ophthalmopathy, total thyroxine levels, and a previous relapse correlated significantly with a further relapse.

Neonatal total gastrectomy.

A 2-day-old, female infant underwent total gastrectomy for spontaneous gastric gangrene and perforation. She developed the following complications: growth retardation, vitamin B12 deficiency, post-gastrectomy dumping syndrome, and occasional bile regurgitation. Nutritional management is described. The two previously reported survivors of total gastrectomy in the neonatal period are reviewed.

Ultrasonic systolic blood pressure gradient between upper and lower limbs in normal term Chinese neonates.

The determination of a normal pattern of systolic blood pressure (SBP) gradient between upper limbs (UL) and lower limbs (LL) in neonates is important in the diagnosis of the coarctation syndrome. The scarcity of studies of normal neonates and the conflict of opinion prompted us to evaluate this problem. The UL and LL systolic blood pressures of 100 normal term Chinese neonates were measured by the Doppler Ultrasonic method (Roche Arteriosonde 1020). Under resting condition, the majority (89%) of our neonates had a negative SBP gradient (LL greater than UL). The mean LL SBP (70.1 mmHg) was significantly higher than that of the UL (59.5 mmHg), p less than 0.001. Eleven out of 100 of our neonates had a positive (UL greater than LL) SBP gradient. Eight of these were less than 1 week old. None had a positive gradient of more than 20 mmHg. According to the results of our study, during the first week of life, normal neonates may have upper limb pressure greater than lower limb of up to 20 mmHg.

Reliability of transcutaneous oxygen monitoring of critically ill children in a general pediatric unit.

While transcutaneous continuous monitoring of partial pressure of oxygen (TcPO2) is a proven valuable diagnostic tool in intensive care of sick neonates, its use in older children is less well defined. The purpose of this study is to establish the accuracy and reliability of TcPO2 as a reflection of arterial partial pressure of oxygen (PaO2) in critically ill pediatric patients. Twenty-six children, age ranging from 4 days to 13 years, were studied. The main diagnostic categories were cardiac 54 per cent, respiratory 27 per cent, gastrointestinal 15 per cent, and neurologic 4 per cent. Forty three estimations of PaO2 (by radial arterial sampling) and TcPO2 (by cutaneous monitor) were obtained simultaneously. Their correlation coefficient, regression equation, and confidence limits were calculated by standard statistical methods with the aid of a microcomputer. Our data show that the high degree of correlation between TcPO2 and PaO2 is highly significant (r = 0.90, p less than 0.001) for the full range of PaO2 between 0 to 200 mm Hg. At the lower range of PaO2 (0-79 mm Hg), the degree of correlation (r = 0.91, p less than 0.001) is better than that (r = 0.77, p less than 0.001) at the higher range (80-200 mm Hg), although the difference between the two correlation coefficients is not significant (p greater than 0.05). It is important to note that TcPO2 consistently underestimates the PaO2 and the 95% confidence limits are rather wide. We conclude that TcPO2 is a reasonably accurate reflection of PaO2 in critically ill pediatric patients. Its main advantage is in predicting and showing trends in tissue oxygenation by noninvasive means. However, when critical assessment of the degree of hypoxemia is required, TcPO2 is no substitute for PaO2.

Postgraduate medical training and certification at the National University of Singapore.

The history of postgraduate medical education in Singapore is described culminating in the award of the local higher qualification - the master of Medicine, equivalent to the higher qualifications awarded by the Royal Colleges in UK and Australasia. Initially, in 1971, the M.Med. in Internal Medicine, Paediatrics, Obstetrics and Gynaecology and Surgery and the M.Sc. in Public Health and Occupational Medicine were awarded and since then, the M.Med. in Anaesthesia and Psychiatry were also awarded. At present, the courses leading to the Examinations are well attended not only by local postgraduates but also by doctors from overseas. The number of postgraduates certified over the various period in Singapore is documented.

Antenatal diagnosis of fetal abnormalities.

Fetal abnormalities may be strongly inherited e.g. in the Mendelian diseases. Some of the abnormalities are due to detectable chromosome anomalies, while the majority of fetal abnormalities arise as a result of the interaction of polygenes and environmental factors. The process of fetal abnormality diagnosis depends on a careful taking of the history and its evaluation. The clinical examination of the fetus by real time ultrasound, if relevant and finally special investigations which are to some extent invasive such as chorionic villus sampling, amniocentesis and fetal blood sampling. The fetal tissue so obtained may be assessed for their genetic structure by DNA recombinant methods, or the disease may be diagnosed by analysis of the genic products. The commoner hereditary diseases probing fetal abnormalities in S.E. Asia are described and the diagnosis of these diseases discussed. Fetal diagnosis, at the moment, is still labour intensive and costly and must be applied in a discriminate fashion.

Hb E beta +-thalassaemia in west Malaysia: clinical features in the most common beta-thalassaemia mutation of the Malays [IVS 1-5 (G-->C)].

Patients with the Hb beta + [IVS 1-5 (G-->C)] clinically presented as beta-thalassaemia intermedia and remained asymptomatic in the absence of blood transfusions. With or without blood transfusions the patients were short and had moderate to marked thalassaemia facies. Children who received blood transfusions showed progressive iron loading with age. The serum ferritin and serum alanine transaminase levels were significantly raised in the patients who were given blood transfusions. In the presence of blood transfusions, and absence of adequate iron chelation therapy, splenectomy became an inevitable event at some stage of the disease because of increasing transfusing requirements.

Peripheral haemolysis, lipid peroxidation, iron status, and vitamin E in haemoglobin H syndromes in West Malaysia.

Following complete DNA characterisation patients with Hb H disease were assigned into two groups: deletional (alpha +/alpha o) and non deletional (HbCS/alpha o). Earlier studies have indicated that the group with (HbCS/alpha o) has more severe clinical problems. The serum malonyldialdehyde (MDA) levels, a secondary product of lipid peroxidation were within the normal range, though significantly higher levels of MDA were seen in the non-deletional type of Hb H disease when compared with the deletional type. Markedly low vitamin E levels were also seen in the former group. There were no significant differences in clinical severity may be attributed to an interplay of the accelerated destruction of damaged mature red blood cells secondary to the oxidative denaturation of Hb H and inclusion precipitation; higher levels of Hb H and more inclusion precipitation were seen in the group with (HbCS/alpha o). Low levels of vitamin E in the (HbCS/alpha o) group being due to its consumption in the neutralisation of free radicals formed with the oxidation of globin chains.

Serum ferritin concentrations in transfusion dependent beta-thalassaemia.

Patients on a moderate red cell transfusion programme have iron overload where the concentrations of the serum ferritin were inappropriate to increases in the transfusion load as a result of limitations of apoferritin synthesis and conversion of ferritin into haemosiderin. This study confirms the limitations for the use of estimations of the serum ferritin to evaluate the iron status in patients with expected high overload as would be seen in patients on many years of maintenance red cell transfusions in the absence of iron chelation therapy. Poor compliance, inadequate dosage of Desferal (deferoxamine), and the late initiation of iron chelation therapy were factors that were considered in the patients with failure of response to iron chelation.

Molecular analysis of Hb Q-H disease and Hb Q-Hb E in a Singaporean family.

Hb Q (alpha 74Asp-His) results from a mutation in the alpha-gene such that abnormal alpha Q-chains are synthesized. The alpha Q-chains combine with the normal Beta A-chains to form abnormal Hb alpha 2Q beta 2A (Hb Q). Hb Q-H disease is rare, and has been reported only in the Chinese. We report here a Chinese family, were the mother diagnosed with Hb Q-H disease and the father with Hb E heterozygosity and a child with Hb Q-E-thalassemia. Thalassemia screening of the mother's blood revealed a Hb level of 6.8g/dl with low MCV and MCH. Her blood film was indicative of thalassemia. Cellulose acetate electrophoresis showed Hb H and Hb Q with the absence of Hb A. Globin chain biosynthesis was carried out and alpha Q- and beta-chains were detected. Normal alpha- chains were absent. Digestion of the mother's DNA with Bam HI and Bgl II followed by hybridization with the 1.5 kb alpha-Pst probe showed a two alpha-gene deletion on one chromosome and the -alpha Q chain mutant with the -alpha 4.2 defect on the other chromosome. DNA amplification studies indicated the two-gene deletion to be of the -SEA/ defect. The patient was concluded to possess Hb Q-H disease (--SEA/-alpha 4.2Q). Cellulose acetate electrophoresis of the father's blood showed the presence of Hb A, F and E. Molecular analysis of the father's DNA confirmed an intact set of alpha-genes (alpha alpha/alpha alpha). Globin chain biosynthesis of fetal blood of their child showed gamma, beta A, beta E, alpha A and alpha Q-chains. Molecular analysis of the child's DNA showed one alpha-gene deletion, thus giving a genotype of alpha alpha/-alpha 4.2Q beta beta E.

The genetic basis of cleft lip and palate deformity.

The embryology of the normal lip and palate and the abnormal development of these structures causing cleft lip (CL) and cleft palate (CP) are discussed. As the development of the lip and palate is not dependent on a single factor but on many factors, it is understandable that CL and CP may occur as a result of abnormalities of genes of large mutant effect (i.e. Mendelian mutant genes), or due to chromosomal anomalies. However, these 2 causes are relatively uncommon and the commonest mode of production is dependent on both genetic and environmental factors. The mechanisms whereby these 3 groups may produce CL and CP will be discussed. Since the modes of inheritance differ in the 3 groups, it is important to discover which group a particular patient belongs to. The genetic load is high in the Mendelian group, is low usually in those due to chromosome disorders, and may be low or high in the last group depending on the polygenes as well as environmental factors. In this last group, empiric risk figures may be calculated for future offspring to be affected. The prenatal diagnosis of CL and CP is also discussed.

Prevention of thalassaemias in South-East Asia.

There are about 55 million people in South-East Asia carrying a thalassaemia gene or a haemoglobin E gene. It is thus not surprising that there are large numbers of patients suffering from beta thalassaemia major, HbE-beta thalassaemia, HbH disease and babies born dead with homozygous alpha thalassaemia (Barts hydrops fetalis). The present methods available for the management of these disorders are discussed and are far from ideal and patients may die from these diseases in spite of treatment, and for many during their short life span, the quality of life is poor. It is therefore argued that prevention of the birth of such individuals is the only satisfactory method of 'management'. In this regard, population screening methods are described and the practicality and usefulness of such population screening for S.E. Asia are discussed. Prenatal diagnosis for these disorders have reached a stage where it is a practical proposition and the various methods using chain separation of fetal blood, and DNA recombinant analysis of fetal cells are described.