Ting Fei Ho

Analysis of P wave and P dispersion in children with secundum atrial septal defect.

Background: P maximum and P dispersion are evaluated as predictors of paroxysmal atrial fibrillation in adults. In this study, these variables are being investigated in children with secundum ASD in comparison with that of normal controls and in relation to size of ASD and the presence or absence of atrial dilation.

The prevalence of obesity in Singapore primary school children

ABSTRACT. The purpose of this study is to survey the prevalence of obesity in Singapore primary school children from 1976 to 1980. The number of children screened comprised of 221,988 in primary I and 218,104 in primary VI. The male to female ratio was 1.04:1. Obesity is defined as body weight above 120% of Harvard standard weight for height. The overall prevalence rate was 3.51% with a significantly higher rate in boys (3.95%) than in girls (3.06%), p < 0.0001. This sex difference prevailed in both the primary I and primary VI group. Furthermore, primary VI students had a higher prevalence rate (4.29%) compared to the primary I students (2.75%) p < 0.0001. The prevalence rates were rising over the years with a rate of 5.33% in 1980 compared to that in 1976 (1.80%). Our observations suggest that the problem of obesity is an increasing one. The tendency to become obese increases with age and boys are more prone to obesity.

Reliability of Transcutaneous Oxygen Monitoring of Critically III 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 Pa o2 (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 < 0.001) for the full range of Pa o2 between 0 to 200 mm Hg. At the lower range of Pao2 (0-79 mm Hg), the degree of correlation (r = 0.91, p < 0.001) is better than that (r = 0.77, p < 0.001) at the higher range (80-200 mm Hg), although the difference between the two correlation coefficients is not significant (p > 0.05). It is important to note that TcPo 2 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.

QT Dispersion in Healthy Chinese Children and Adolescents

Background:QT dispersion (QTd) reflects the interlead difference in QT interval. It may provide a measure of repolarization inhomogeneity. Studies on QTd mainly involve adults, while QTd in children are less well studied. The aim of this study was to evaluate QTd in healthy children and assess the relationship of gender, age, and anthropometric parameters, viz. weight (W), height (H), body mass index (BMI), and body surface area (BSA) to QTd.

Ventricular bigeminy misdiagnosed as fetal bradycardia by cardiotocography--the value of non-invasive fetal electrocardiography.

Abstract We document the value of non-invasive fetal electrocardiography (fECG) in a case of fetal arrhythmia in which an unnecessary cesarean section was almost performed. The fetal heart rate (fHR) was 60–70 beats per minute (bpm) on the cardiotocography (CTG), with occasional, sudden fluctuations to 130 bpm. This was probably a result of the technical limitations of the CTG.

Signal-averaged electrocardiography in healthy children: Relationship with age, sex, and anthropometry

Signal-averaged electrocardiograms (SAECGs) have been found to be influenced by sex and anthropometry in adults. The purpose of this study was to evaluate this relationship in children. Total filtered QRS duration (TQRS), duration of high-frequency, low-amplitude signals in the terminal portion of the QRS complex that were less than 40 microV (HFLA) root-mean-square voltage in the last 40 ms of the filtered QRS (RMS40) were determined by high-resolution electrocardiographic (ECG) recording (MAC 15 ECG System, Marquette Electronics, Milwaukee, WI). These parameters were correlated with age, sex, body weight, height, relative weight, body mass index, and body surface area. As HFLA and RMS40 were not normally distributed, they were logarithmically transformed for regression analysis. The best subset multiple regression procedure was used to evaluate the variables that would optimally influence SAECG measurements and to obtain regression equations for the prediction of each SAECG parameter. Although univariate analysis shows that almost all the body characteristics and age are significantly correlated with SAECGs, multiple regression analysis reveals that TQRS is significantly influenced by height (P < .0001), relative weight (P = .012), and body mass index (P = .041); HFLA is influenced by weight (P = .001), height (P = .004), and body mass index (P = .001); and RMS40 is influenced by height (P < .0001) and relative weight (P = .001). Sex is noted to significantly influence both TQRS and RMS40 (P < .0001, P = .002, respectively), while HFLA is found to be significantly related to age (P = .001). In summary, SAECGs in Chinese children are shown to be influenced by height, weight, and relative weight or body mass index, but not body surface area, while age and sex also significantly contribute to the variation of some SAECG parameters.

Age and Gender Specific Criteria for Signal-Averaged Electrocardiographic Parameters in Healthy Chinese Children

Background: Detection of late potentials (LPs) using signal‐averaged electrocardiograms (SAECGs) is believed to help in the prediction of malignant ventricular arrhythmias and sudden cardiac death in adults. Criteria for detection of LPs in adults may not be applicable for children, as these measurements are known to be age and sex specific.

Evaluation of rate-pressure product in obese children.

The purpose of this study was to evaluate the relationship between rate‐pressure product (RPP) and degree of obesity in 511 obese 7 and 12 year old Chinese children. Obesity was assessed by anthropometry and skinfold thickness. The children were defined obese by relative weight (RW) > 120%. Bodyweight (W) and height (H) were used to derive body mass index (W/H2). Brachial systolic and diastolic pressures in these children were measured by cuff sphygmomanometry. RPP was calculated by the formula: heart rate x mean arterial pressure.

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 Arterio sonde 1020). Under resting condition, the majority (89%) of our neonates had a negative SBP gradient (LL > UL). The mean LL SBP (70.1 mmHg) was significantly higher than that of the UL (59.5 mmHg), p < 0.001. Eleven out of 100 of our neonates had a positive (UL > 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.

Osmolality of Rice Water, Dextrose–Saline Solution and Formula Milk—Implication in the Management of Infantile Gastroenteritis

Rice water popular in some parts of the world as a folk remedy for infantile diarrhea has recently been found to be an effective oral rehydration therapy for the acute phase of infantile gastroenteritis. The osmolality of rice water as compared to dextrose-saline (D/S) and formula milk was studied. Also examined was the effect of doubling the dilution on the osmolalities of these solutions. Results show that rice water has a very low osmolality (mean +or-SD=8.9 +or- 3.4 mOsm/kg) almost 36 times lower than that of D/S (mean +or- SD= 317.5 +or- 7.5 mOsm/kg). Furthermore the osmolality of D/S was found to vary widely from 131.0 mOsm/kg to 473.6 mOsm/kg. Doubling dilution does not result in much reduction in the osmolality of rice water which is suggestive of the fact that it may be a supersaturated solution. The ease of its preparation and its low osmolality seem to suggest that rice water may be a preferable form of oral rehydration therapy for infantile diarrhea compared to D/S and formula milk especially for outpatient use. (authors)