Giles N. Cattermole

Mid-arm circumference can be used to estimate children's weights.

INTRODUCTION Accurate measurement of childrens weight is rarely possible in paediatric resuscitation, and rapid estimates are made to ensure appropriate drug and fluid doses and equipment selection. Weight is commonly estimated from formulae based on childrens age, or from their height using the Broselow tape. Foot-length and mid-arm circumference have also been suggested as the basis of weight-estimation formulae. OBJECTIVES To determine which of age, height, foot-length or mid-arm circumference had the strongest relationship with weight in healthy children, to derive a simple weight-estimation formula from the strongest correlate, and to compare its performance with existing weight-estimation tools. METHODS This was a population-based prospective observational study of Hong Kong Chinese children aged 1-11 years old last birthday. Weight was measured to the nearest 0.2 kg; height, foot-length and mid-arm circumference to the nearest 0.1 cm. Multiple regression analysis was used to determine the strongest independent relationships with weight, and linear regression analysis derived a weight-estimation formula. Accuracy and precision of this formula were compared with standard age-based and height-based weight-estimation methods. RESULTS Mid-arm circumference had the strongest relationship with weight, and this relationship grew stronger with age. The formula, weight [kg]=(mid-arm circumference [cm]-10) x 3, was at least as accurate and precise as the Broselow method and outperformed the age-based rule in school-age children, but was inadequate in pre-school children. CONCLUSION This weight-estimation formula based on mid-arm circumference is reliable for use in school-age children, and an arm-tape could be considered as an alternative to the Broselow tape in this population.

The normal ranges of cardiovascular parameters in children measured using the Ultrasonic Cardiac Output Monitor.

Objective:The Ultrasonic Cardiac Output Monitor is a noninvasive method of hemodynamic assessment and monitoring in critically ill patients. There are no published reference ranges for normal values in children for this device. This study aimed to establish normal ranges for cardiovascular indices measured using Ultrasonic Cardiac Output Monitor in children aged 0–12 yrs old and to assess interobserver reliability. Design:This was a population-based cross-sectional observational study. Setting:Schools and kindergartens in Hong Kong. Subjects:Chinese children aged up to 12 yrs old. Interventions:Two operators performed Ultrasonic Cardiac Output Monitor scans on each child together with standard oscillometric measurement of blood pressure and heart rate. Software intrinsic to the Ultrasonic Cardiac Output Monitor device produces values for stroke volume, cardiac output, and systemic vascular resistance. For each parameter, normal ranges were defined as lying between the 2.5th and 97.5th percentiles. Interobserver reliability was assessed with Bland-Altman plots, coefficients of variation, and intraclass correlation. Measurements and Main Results:A total of 1,197 Chinese children (55% boys) were scanned. Normal ranges of values for cardiac output, stroke volume, and systemic vascular resistance indices are presented. Interobserver reliability for Ultrasonic Cardiac Output Monitor was superior to that for standard blood pressure and heart rate measurement. Conclusions:This large study presents normal values for cardiovascular indices in children using the Ultrasonic Cardiac Output Monitor with good interobserver reliability.

Age-based formulae to estimate children's weight in the emergency department

Objective To develop an age-based weight estimation rule in a Chinese population and to compare its performance with existing formulae. Design Population-based observational study. Setting Schools and kindergartens in Hong Kong. Subjects Healthy Chinese children aged 1–10 years old on their last birthday. Interventions Weight was measured to the nearest 0.2 kg. Main outcome measures Linear regression was used to derive a simple formula relating weight to the childs age on his or her last birthday. The accuracy and precision of different age-based weight formulae was compared using coefficient of variation, Bland Altman plots, and by determining the proportion of children with estimates >30% outside the actual weight. Results The Chinese Age Weight Rule is a simple linear formula that is more accurate than and at least as precise as any other age-based weight estimation rule: weight in kg=(3×age last birthday)+5. It is accurate and precise in children <7 years old, but all age-based weight estimates are imprecise in older children. Conclusions The Chinese Age Weight Rule should be used in a Chinese population in preference to any other age-based weight estimation rule. Caution should be taken when using it in older children in whom other weight-estimation tools may be more appropriate.

Assessment of quality of life and functional outcome in patients sustaining moderate and major trauma: a multicentre, prospective cohort study.

BACKGROUND Trauma care systems aim to reduce both death and disability, yet there is little data on post-trauma health status and functional outcome. OBJECTIVES To evaluate baseline, discharge, six month and 12 month post-trauma quality of life, functional outcome and predictors of quality of life in Hong Kong. METHODS Multicentre, prospective cohort study using data from the trauma registries of three regional trauma centres in Hong Kong. Trauma patients with an ISS≥9 and aged≥18 years were included. The main outcome measures were the physical component summary (PCS) score and mental component summary (MCS) scores of the Short-Form 36 (SF36) for health status, and the extended Glasgow Outcome Scale (GOSE) for functional outcome. RESULTS Between 1 January 2010 and 31 September 2010, 400 patients (mean age 53.3 years; range 18-106; 69.5% male) were recruited to the study. There were no statistically significant differences in baseline characteristics between responders (N=177) and surviving non-responders (N=163). However, there were significant differences between these groups and the group of patients who died (N=60). Only 16/400 (4%) cases reported a GOSE≥7. 62/400 (15.5%) responders reached the HK population norm for PCS. 125/400 (31%) responders reached the HK population norm for MCS. If non-responders had similar outcomes to responders, then the percentages for GOSE≥7 would rise from 4% to 8%, for PCS from 15.5% to 30%, and for MCS from 31% to 60%. Univariate analysis showed that 12-month poor quality of life was significantly associated with age>65 years (OR 4.77), male gender (OR 0.44), pre-injury health problems (OR 2.30), admission to ICU (OR 2.15), ISS score 26-40 (OR 3.72), baseline PCS (OR 0.89), one-month PCS (OR 0.89), one-month MCS (OR 0.97), 6-month PCS (OR 0.76) and 6-month MCS (OR 0.97). CONCLUSION For patients sustaining moderate or major trauma in Hong Kong at 12 months after injury<1 in 10 patients had an excellent recovery, ≤3 in 10 reached a physical health status score≥Hong Kong norm, although as many as 6 in 10 patients had a mental health status score which is≥Hong Kong norm.

Derivation of a prognostic score for identifying critically ill patients in an emergency department resuscitation room

INTRODUCTION Several prognostic scores exist for critically ill patients, including APACHE II, Revised Trauma Score (RTS), Rapid Emergency Medicine Score (REMS) and Modified Early Warning Score (MEWS). However, there is no widely used score specifically designed to predict the likelihood of early intensive care unit (ICU) admission or death in undifferentiated emergency department (ED) resuscitation room patients. We aimed to derive such a score and compare it with other similar scores. METHODS This was a single centre study of consecutive adult resuscitation room patients over one month. Physiological and blood test variables were compared according to the composite primary outcome: admission to ICU or death within 7 days of attendance. Multivariate logistic regression was used to derive a prediction score which was compared with other scores using ROC (receiver operating characteristic) analysis. RESULTS 330 patients were included in the study, of whom 77 were admitted to ICU or died within 7 days. A prediction score was derived using the following parameters: systolic blood pressure; Glasgow coma score; blood glucose; bicarbonate; white cell count; and a history of metastates. This score significantly out-performed APACHE II, RTS, REMS and MEWS with an area under the ROC curve of 0.909 (95% CI 0.872-0.938). CONCLUSION The Prince of Wales Emergency Department Score (PEDS) is a new prognostic score to predict the likelihood of early ICU admission or death in undifferentiated resuscitation room patients. Further studies are needed to validate and refine this potentially useful tool.

Too tall for the tape: the weight of schoolchildren who do not fit the Broselow tape.

Background In paediatric resuscitation, for a rapid and accurate estimate of childrens weight, the Broselow tape can be used in children who are 46–144 cm tall. The Broselow tape has previously been found to provide the most accurate estimate of childrens weight internationally, but it is not known how many fall outside the range of the tape, or whether such children can be assumed to be of adult weight, or how otherwise to estimate the weight of these children. Objectives To determine what proportion of children in different age groups falls outside the limits of the Broselow tape, how their weight compares with that of the adults and what correlates most strongly with weight in these children. Methods This was a population-based prospective observational study of Chinese children up to 12 years old, from schools in Hong Kong. Weight was measured to the nearest 0.2 kg, and the height, foot-length and mid-arm circumference (MAC) were measured to the nearest 0.1 cm. Results 40% of 10-year olds and 70% of 11-year olds were too tall for the tape. Their median weight was 41.9 kg. This was significantly less than the median weight of 18-year olds (55 kg, p<0.0001) in Hong Kong. The strongest correlate with weight in these children was MAC. Conclusions The Broselow tape is inappropriate for use in most children over 10 years old. Children too tall for the tape cannot be assumed to be of adult weight; to do so would imply an average overestimate of 30%. Weight estimates in older children could be based on MAC.

Opiates should be avoided in acute decompensated heart failure

We were pleased to read the paper by Peacock et al 1 warning of the dangers of morphine therapy in acute decompensated heart failure. This retrospective review was the largest yet performed, with nearly 150 000 patients in the database. The most concerning finding was an increased risk of mortality with an odds ratio of …

THERM: the Resuscitation Management score. A prognostic tool to identify critically ill patients in the emergency department

Introduction Prognostic scores are widely used in the emergency department (ED) to stratify risk for critically ill patients. The Prince of Wales ED Score (PEDS) was derived specifically for patients in an ED resuscitation room to predict death or intensive care unit (ICU) admission. We aimed to validate and refine this score, in comparison with other scores including the National Early Warning Score (NEWS). Methods This was a single-centre prospective study of adult resuscitation-room patients over 3 months. Comparison of scores was made using receiver operating characteristic analysis. Physiological and blood test variables were compared according to the composite primary outcome: admission to ICU or death within 7 days of attendance. Multivariate logistic regression was used to derive a new prediction score, which was validated in comparison with NEWS using the historic dataset from which PEDS had been derived. Results 234 patients were included; 37 were admitted to ICU or died within 7 days. PEDS performed adequately but was not superior to other scores. A simple pragmatic score, The Resuscitation Management score (THERM) was derived which outperformed NEWS in derivation and validation sets. Conclusions PEDS is at least as good as other scores, including NEWS. However, it is unwieldy and relies on results not immediately accessible in the ED. THERM is a new score, derived and validated in an ED setting, using variables readily available, and simple to calculate and stratify. THERM outperforms NEWS and could be used in preference in critically ill ED patients.

Nurse-initiated defibrillation: are nurses confident enough?

Objectives To determine the capability of nurses to identify ventricular fibrillation (VF) and ventricular tachycardia (VT) rhythms on an ECG and carry out subsequent defibrillation on their own as soon as they identify and confirm cardiac arrest. Methods This was a prospective cohort study to determine the capability of emergency department (ED) nurses to recognise VF or pulseless VT correctly and their willingness to perform defibrillation immediately in an ED of a teaching hospital in Hong Kong. A questionnaire was completed before and after a teaching session focusing on the identification of rhythms in cardiac arrest and defibrillation skills. Correct answers for both ECG interpretation and defibrillation decisions scored one point for each question. The differences in mean scores between the pre-teaching and post-teaching questionnaires of all nurses were calculated. Results 51 pre-teaching and 43 post-teaching questionnaires were collected. There were no statistically significant changes in ECG scores after teaching. For defibrillation scores, there was an overall improvement in the defibrillation decision (absolute mean difference 0.42, p=0.014). Performance was also improved by the teaching (absolute mean difference 0.465, p=0.046), reflected by the combination of both scores. Two-thirds (67%) of nurses became more confident in managing patients with shockable rhythms. Conclusion Nurses improve in defibrillation decision-making skills and confidence after appropriate brief, focused in-house training.

The normal ranges of cardiovascular parameters measured using the ultrasonic cardiac output monitor

The ultrasonic cardiac output monitor (USCOM) is a noninvasive transcutaneous continuous wave Doppler method for assessing hemodynamics. There are no published reference ranges for normal values in adults (aged 18–60 years) for this device. This study aimed to (1) measure cardiovascular indices using USCOM in healthy adults aged 18–60 years; (2) combine these data with those for healthy children (aged 0–12), adolescents (aged 12–18), and the elderly (aged over 60) from our previously published studies in order to present normal ranges for all ages, and (3) establish normal ranges of USCOM‐derived variables according to both weight and age. This was a population‐based cross‐sectional observational study of healthy Chinese subjects aged 0.5–89 years in Hong Kong. USCOM scans were performed on all subjects, to produce measurements including stroke volume, cardiac output, and systemic vascular resistance. Data from previously published studies (children, adolescents, and the elderly) were included. Normal ranges were defined as lying between the 2.5th and 97.5th percentiles. A total of 2218 subjects were studied (mean age = 16.4, range = 0.5–89; 52% male). From previous studies, 1197 children (aged 0–12, 55% male), 590 adolescents (aged 12–18, 49% male), and 77 elderly (aged 60–89, 55% male) were included. New data were collected from 354 adults aged 18–60 (47% male). Normal ranges are presented according to age and weight. We present comprehensive normal ranges for hemodynamic parameters obtained with USCOM in healthy subjects of all ages from infancy to the elderly.