Anthropometric and physiological measurements in healthy children.

1. Normal ranges for ultrasonic cardiac output monitor-derived cardiovascular indices are derived for Chinese children aged 1 to 12 years in Hong Kong. 2. A simple formula for calculating stroke volume is constructed, but the error varies from 8 to 40%. 3. Stroke volume index and, to a lesser extent, the cardiac index generally increase from ages 1 to 5 years, but plateau or fall slightly thereafter.

Validation of the APLS age-based vital signs reference ranges in a Chinese population.

UNLABELLED: Reference ranges for vital signs may differ significantly among children of different ethnic origins. AIM: (1) To validate the Advanced Paediatric Life Support (APLS) age-based vital signs reference ranges in Chinese children in Hong Kong. (2) To derive age-based centile curves for systolic blood pressure, heart rate and respiratory rate for Chinese children. (3) To summarize the reference ranges in a table format appropriate for applying APLS to ethnic Chinese patients. METHOD: A cross-sectional study was performed on a population of healthy Chinese children recruited from 8 kindergartens and 6 primary schools in Hong Kong. Trained operators visit the sites to obtain measurements. Age-groups: small toddlers (12-23 months); pre-school (24-59 months); and school (60-143 months). Z-test was used to assess statistical significance for proportions of each parameter falling outside the APLS reference range. One-sample t-test was used for comparison with APLS means according to age-groups. LMS Chartmaker Pro v2.3 software was used to describe the data in centile curves. RESULTS: A total of 1353 patients (55.1% boys) were included. For heart rate, systolic blood pressure and respiratory rate respectively, 34.1%, 55.9% and 55.7% of corresponding measurements were outside the APLS age-based reference ranges. In the 'pre-school' and 'school' age-groups, the mean value for blood pressure is significantly higher, and the mean values for heart rate and respiratory rate significantly lower, in comparison to APLS mean values. CONCLUSION: Independently derived vital signs reference ranges are more appropriate for use when applying APLS to Chinese patients in Hong Kong.

Disease severity prediction for nursing home-acquired pneumonia in the emergency department.

BACKGROUND: Prediction rules exist for the assessment of community-acquired pneumonia but their use in nursing home-acquired pneumonia (NHAP) remains undefined. The objectives of this study were to compare the prognostic ability for severe NHAP of five prediction rules (PSI, CURB-65, M-ATS, R-ATS, España rule), and to evaluate their usefulness to identify patients with less severe disease in the emergency department for outpatient care. METHODS: A prospective observational study of consecutive NHAP patients was conducted at a university teaching hospital emergency department in Hong Kong between January 2004 and June 2005. The primary outcome was severe pneumonia (defined as combined 30-day mortality and/or intensive care unit (ICU) admission). RESULTS: 767 consecutive NHAP patients were included. Mean (SD) age was 83.4 (9.0) years; 350 (45.6%) were male and 644 (84.0%) had coexisting illness. 95 patients died within 30 days (12.4%), five patients were admitted to the ICU (0.7%) and 98 patients had severe pneumonia (12.8%). Sensitivity and specificity of each decision rule ranged from 37.8% to 95.9% and 15.1% to 87.6% respectively. The overall predictive performance of each rule was between 0.627 and 0.712. The negative likelihood ratios of PSI (0.27) and CURB-65 (0.23) were lower than M-ATS (0.71), R-ATS (0.45) and España (0.39). After excluding 204 patients with either poor functional status or those >90 years of age, sensitivities of M-ATS (96.0%) and R-ATS (100%) improved greatly with negative likelihood ratios of <0.1. CONCLUSION: PSI and CURB-65 are useful for identification of patients with less severe NHAP.

Open-access colonoscopy: outcomes of referrals from the emergency department.

AIM: The study investigated the diagnostic outcome of colonoscopy referrals from the emergency department (ED) via an open-access system. METHOD: A retrospective cohort study over two years was performed on all patients under 65 years referred for open-access colonoscopy by the ED in a hospital with an annual ED attendance of 140,000. Patient characteristics and presenting symptoms were retrieved. Waiting times from presentation to colonoscopy were recorded. RESULTS: Over a 2-year period, 266 patients were referred, of whom 37 defaulted, leaving 229 patients who had a colonoscopy. The mean age was 48.3 ± 11.3 (SD) and the female/male ratio was 229/125. The most frequent presenting symptoms included: rectal bleeding (n = 142, 62%), change of bowel habit (n = 47, 20.5%) and abdominal pain (n = 40, 17.5%). The median waiting time from presentation to colonoscopy was 17 (range 1-69) days. A positive colonoscopic finding was recorded in 45.4%, including colorectal cancer in 12 (5.2%). CONCLUSION: The rate of a positive diagnoses from the ED-based colonoscopy referral service was comparable to that of the general Hong Kong population. This approach may help to reduce the waiting time for colonoscopy in a specialist colorectal clinic.

Operational definitions improve reliability of the age-related white matter changes scale.

BACKGROUND AND PURPOSE: Although the age-related white matter changes (ARWMC) scale has been advocated to be applicable to both MRI and CT for assessing the severity of WMC, its inter-rater reliability on CT is only fair. We aimed to operationalize the ARWMC scale and investigate the effect of this operationalization on the reliability and validity on MRI and CT. METHODS: Operational definitions of the ARWMC scale were derived from Erkinjuntti research criteria for subcortical vascular dementia and Scheltens scale. Using original and operationalized ARWMC scale, eight observers recorded the time for rating per MRI and per CT. We investigated the inter-rater and intrarater reliability as well as validity against volume using data from 97 stroke patients. RESULTS: Inter-rater reliability of the operationalized scale on CT (0.874, 95% confidence interval [0.780-0.934]) was better than the original scale (0.569, 95% confidence interval [0.247-0.775]). Its intrarater reliability on CT (0.869) and reliability on MRI (inter-rater: 0.860; intrarater: 0.838) was comparable with the original scale (CT intrarater: 0.750 and on MRI inter-rater: 0.845; intrarater: 0.853). The time required to administer the operationalized scale (4'2″ for MRI and 1'18″ for CT) was similar to that of the original scale (3'56″ for MRI and 1'16″ for CT). The original scale and operationalized scale also significantly correlated with WMC volume (operationalized scale ρ = 0.613, P < 0.001, original scale ρ = 0.638, P < 0.001). CONCLUSION: Operational definitions improve the inter-rater reliability of ARWMC scale on CT, and it correlates with volumetric measurement.

Acute bacterial gastroenteritis: a study of adult patients with positive stool cultures treated in the emergency department.

OBJECTIVES: To investigate the presenting clinical features of acute bacterial gastroenteritis in adult patients treated as outpatients in the emergency department (ED), and the pathogens responsible in this setting and population; and to identify the frequency with which positive stool culture result changes management. METHOD: This was a retrospective study of all patients who attended the accident and emergency department of an university affiliated hospital in Hong Kong over a 12 month period, who satisfied the following inclusion criteria: (a) age >/=16, (b) presented with acute gastroenteritis, (c) treated as outpatients with or without observation, and (d) had positive stool cultures. RESULTS: One hundred and thirty patients were included. Pathogens identified were Vibrio parahaemolyticus (42.3%), Samonella spp (34.6%), Plesiomonas spp (9.2%), Campylobacter spp (6.9%), Aeromonas spp (6.9%), and Shigella spp (6.2%). Mean highest body temperature was 37.5 degrees C (95% confidence intervals (CI) 37.3 to 37.6). Bloody diarrhoea was present in 14 patients (10.8%). Mean duration of diarrhoea, from onset to the completion of stay in ED, was 2.2 days (95% CI 1.7 to 2.7). Likewise, mean duration of abdominal pain was 1.8 days (95% CI 1.5 to 2.1). Mean number of unformed stools per day was 9.3 (95% CI 8.3 to 10.3). Change of management, subsequent to the availability of positive stool culture results, was not required in 115 (88.5%) patients. Ciprofloxacin resistance occurred in eight (6.2%) cases, and seven of nine campylobacter isolates. Campylobacter positive patients had a significantly longer duration of abdominal pain (p=0.0236) and were less likely to be dehydrated (p=0.0103). CONCLUSIONS: Most patients with bacterial gastroenteritis do not present with high fever, bloody diarrhoea, or persistent diarrhoea, but generally have quite severe diarrhoea. Stool cultures do not change management for most patients. Vibrio parahaemolyticus is the commonest bacterial pathogen identified.