Accuracy of weight estimation methods in adults, adolescents and children: a prospective study.

INTRODUCTION: Weight estimation of both adult and paediatric patients is often necessary in emergency or low-resource settings when it is not possible to weigh the patient. There are many methods for paediatric weight estimation, but no standard methods for adults. PAWPER and Mercy tapes are used in children, but have not been assessed in adults. The primary aim of this study was to assess weight estimation methods in patients of all ages. METHODS: Patients were prospectively recruited from emergency and outpatient departments in Kigali, Rwanda. Participants (or guardians) were asked to estimate weight. Investigators collected weight, height, mid-arm circumference (MAC) and humeral-length data. In all participants, estimates of weight were calculated from height and MAC (PAWPER methods), MAC and humeral length (Mercy method). In children, Broselow measurements and age-based formulae were also used. The primary outcome measure was the proportion of estimates within 20% of actual weight (p20). RESULTS: We recruited 947 participants: 307 children, 309 adolescents and 331 adults. For p20, the best methods were: in children, guardian estimate (90.2%) and PAWPER XL-MAC (89.3%); in adolescents, PAWPER XL-MAC (91.3%) and guardian estimate (90.9%); in adults, participant estimate (98.5%) and PAWPER XL-MAC (83.7%). In all age groups, there was a trend of decreasing weight estimation with increasing actual weight. CONCLUSION: This prospective study of weight estimation methods across all age groups is the first adult study of PAWPER and Mercy methods. In children, age-based rules performed poorly. In patients of all ages, the PAWPER XL-MAC and guardian/participant estimates of weight were the most reliable and we would recommend their use in this setting.

Characteristics, physiology and mortality of intubated patients in an emergency care population in sub-Saharan Africa: a prospective cohort study from Kigali, Rwanda.

BACKGROUND: Formalised emergency departments (ED) are in early development in sub-Saharan Africa and there are limited data on emergency airway management in those settings. This study evaluates characteristics and outcomes of ED endotracheal intubation, as well as risk factors for mortality, at a teaching hospital in Rwanda. METHODS: This was a prospective observational study of consecutive patients requiring endotracheal intubation at the University Teaching Hospital of Kigali ED conducted between 1 January and 31 December 2017. A standardised data collection tool was used to record patient demographics, preintubation clinical presentation, indication for intubation, vital signs. medications and equipment used, and periintubation complications. The primary outcome was in-hospital mortality. Univariate associations were determined for risks of mortality. RESULTS: Of 198 intubations were analysed, 72.7% were male and the median age was 35 years (IQR 23-51). Airway protection was the most common indication for intubation (73.7%). Rapid sequence intubation was performed in 74.2% of cases; sedative-only facilitated intubation in 20.6% and non-drug assisted in 5.2%. The most common agents used were Ketamine for sedation (85.4%) and vecuronium for paralysis (65.7%). All patients were successfully intubated within three attempts, 85.4% on the first attempt. During intubation, 23.1% of patients experienced hypoxia, 6.7% aspiration and 3.6% cardiac arrest. Median ED length of stay was 2 days. Outcome data were available for 164 patients of whom 67.7% died. Bonferroni-corrected univariate analysis demonstrated that mortality was associated with higher postintubation shock index (p=0.0007) and lower postintubation systolic blood pressure (SBP) (p=0.0006). CONCLUSION: The first-attempt and overall success rates for intubation in this ED in Rwanda were comparable to those in high-income countries (HIC). Mortality postintubation is associated with lower postintubation SBP and higher postintubation shock index. The high complication and mortality rates suggest the need for better resources and training to address differences in compared with HIC.

Mid-arm circumference can be used to estimate weight of adult and adolescent patients.

OBJECTIVES: Many drug and fluid regimens in emergency medicine are weight dependent in adults, but no standard adult weight estimation tools exist. Paediatric weight is often estimated in emergency situations using methods based on age or height when direct measurement is not possible, and recently, methods based on mid-arm circumference (MAC) have also been developed. The aim of this study was to derive and validate an accurate MAC-based method for weight estimation for use in all age groups. METHODS: Data were obtained from the US National Health and Nutrition Examination Survey (NHANES). MAC-based methods of weight estimation were derived in 8498 subjects (5595 adults aged 16-80 years, 2903 children aged 1-15.9 years) from the NHANES 2011-2012 dataset, using linear regression. NHANES 2009-2010 was used for validation in 9022 subjects (6049 adults aged 16-79 years, 2973 children aged 1-15.9 years). RESULTS: A simplified method of MAC-based weight estimation was derived from linear regression equation: weight in kg=4×MAC (in cm)-50. On validation, results in children aged 1-10.9 years were poor. In adults and children aged 11-15.9 years, over 60%, 90% and 98% of estimates fell, respectively, within 10%, 20% and 30% of actual weights when using the simplified formula. CONCLUSIONS: In this description of a method for estimating weight in adults, we have derived and validated a simplified formula that is at least as precise in adults and adolescents as commonly used paediatric weight estimation tools in children.

Developing and implementing a global emergency medicine course: Lessons learned from Rwanda.

BACKGROUND: There is a growing demand by medical trainees for meaningful, short-term global emergency medicine (EM) experiences. EM programs in high-income countries (HICs) have forged opportunities for their trainees to access this experience in low-and middle-income countries (LMICs). However, few programs in LMICs have created and managed such courses. As more LMICs establish EM programs, these settings are ideal for developing courses beneficial for all participants. We describe our experience of creating and implementing a short-term global EM course in Rwanda. OBJECTIVES: The objectives of this study were to (1) provide EM trainees from HICs with an opportunity to observe global clinical practice and to learn from local experts, (2) provide EM trainees from an LMIC with an opportunity to share their expert knowledge and skills with HIC trainees, (3) create a sustainable model for a short-term global EM course in an LMIC context. METHODS: A global EM curriculum and course were developed in Rwanda, entitled EM in the Tropics Emergency Medicine in the Tropics (EMIT). The following topics were covered: EM systems development, public health, trauma/triage, pediatrics, disaster management, and tropical EM. A one-and two-week course program was created and implemented. RESULTS: EMIT participants rotated through pediatric and adult EDs, Intensive Care Unit, trauma surgery, internal medicine, emergency medical services, and ultrasound training. Activities included bedside teaching, case presentations, ultrasound practice, group lectures, simulation and skills workshops, and a rotation to a district hospital. A total of 11 participants attended: six for both weeks and five for 1 week. The course raised $5000 USD, which was dedicated in full to sponsoring local EM residents to attend international conferences. DISCUSSION: The EMIT course in Rwanda achieved its objectives of teaching and learning between all participants. Benefits of this in-person experience for both visiting and local participants are clear in clinical, intercultural, and professional ways. CONCLUSION: Our experience of developing and implementing EMIT in Rwanda demonstrates that EM programs in LMICs can provide short-term global EM courses that are not only beneficial to all participants, but also logistically and financially sustainable.

Prospective validation of Thrombolysis in Myocardial Infarction and front door Thrombolysis in Myocardial Infarction risk scores in Chinese patients presenting to the ED with chest pain.

BACKGROUND: Chest pain is a common complaint among emergency department (ED) patients. The Thrombolysis in Myocardial Infarction (TIMI) and front door TIMI (FDTIMI) scores are used to risk stratify chest pain patients in many Western countries; they have not been validated in patients with undifferentiated chest pain in Asia. Our objective was to establish the relationship between the TIMI and FDTIMI scores and the 30 day rate of major adverse cardiac outcomes (MACE) in Chinese patients presenting to the ED with chest pain. METHODS: Prospective, single-center, observational cohort study of consecutive patients presenting with chest pain from July 2009 until March 2010 to a Hong Kong university hospital ED. Data collected included patient characteristics, TIMI items and past medical and medication history. Primary outcome was MACE within 30 days of presentation. MACE was a composite outcome of any of the following: death (all causes), readmission with myocardial infarction, acute coronary syndrome not diagnosed at initial ED presentation and coronary revascularization. RESULTS: One thousand patients recruited with complete 30-day follow-up. STEMI patients (n = 75) were excluded. Mean patient age 66.8 ± 13.9 years; 51.7% male. 119 (12.9%) patients had MACE within 30 days of presentation. The incidence of MACE ranged from 0 for TIMI0 to 37.5% for patients with TIMI6/7. Increasing TIMI and FDTIMI scores were associated with a higher incidence of MACE. CONCLUSIONS: This validation suggests that the TIMI/FDTIMI scores can be employed in Hong Kong Chinese; they may be useful for risk stratification of Chinese ED patients with undifferentiated chest pain elsewhere.

Noninvasive transcutaneous Doppler ultrasound-derived hemodynamic reference ranges in Chinese adolescents.

OBJECTIVES: The ultrasonic cardiac output monitor is a noninvasive, quantitative method for measuring and monitoring cardiovascular hemodynamic parameters in patients. The aims of this study were first to establish reference ranges for cardiovascular indices measured by the ultrasonic cardiac output monitor in Chinese children aged 12-18 yr, second to assess the interobserver reliability of the method, and third to compare these ranges with a Caucasian group from Australia. DESIGN, SETTING, AND SUBJECTS: This was a population-based cross-sectional cohort study of Chinese adolescents 12-18 years old, performed in secondary schools in Hong Kong. INTERVENTIONS: Ultrasonic cardiac output monitor scans were performed on each subject to measure stroke volume, cardiac output, and systemic vascular resistance together with standard oscillometric measurement of blood pressure and heart rate. Ultrasonic cardiac output monitor parameters were also standardized by deriving body surface area referenced indices. Normal ranges were defined as lying within two standard deviations on either side of the mean. To assess interobserver variability, a second, blinded operator repeated 17% of scans. MEASUREMENTS AND MAIN RESULTS: A total of 590 Chinese adolescents (49% boys) were scanned. Normal ranges for cardiac output, cardiac index, stroke volume, stroke volume index, stroke volume resistance, and systemic vascular resistance index are presented. Males had a significantly higher mean stroke volume, cardiac output, and systemic vascular resistance index compared with females (p < 0.05), but no significant differences were found for the indexed values. When compared with a group of 31 Australian Caucasian adolescents (71% boys), Chinese adolescents have a significantly lower cardiac output and stroke volume (p <0.05), but these differences disappeared when adjusted for body surface area (i.e., stroke volume index, cardiac index, and systemic vascular resistance index). Interobserver variability of ultrasonic cardiac output monitor-derived stroke volume showed a coefficient of variation of 10.2%, a correlation coefficient of 0.90 (95% confidence interval 0.85-0.93), while Bland-Altman analysis showed a mean bias of 1.5% (95% limits of agreement were -19.9% to 23.0%). CONCLUSIONS: This study presents normal values for cardiovascular indices in Chinese adolescents using the ultrasonic cardiac output monitor. When referenced to body surface area, the differences between Caucasians and Chinese were insignificant.

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.

Comparison of adult weight estimation methods for use during emergency medical care.

OBJECTIVE: Many emergency drug and fluid doses are weight dependent in adults, but in resuscitation and low-resource settings it can be impractical or impossible to weigh a patient. It is especially important to obtain accurate weight estimation for dose calculations for emergency drugs with narrow therapeutic ranges. Several weight estimation methods have been proposed for use in adults, but none is widely established. The aim of this study was to compare the accuracy of adult weight estimation methods. METHODS: Demographic and body measurement data were obtained from the US National Health and Nutrition Examination Survey (NHANES), and 7 previously published weight estimation methods were used to estimate the weight for each individual. The primary outcomes were the proportions of estimates within 10% and 20% of actual weight (P10, P20). An acceptable accuracy was predetermined to be P10 = 70% and P20 = 95%. RESULTS: The data set included 5158 adults (51.2% women) with sufficient data to calculate all weight estimation methods. The Lorenz method performed best (P10 = 86.8%, P20 = 99.4%) and met the standard of acceptability across sex and body mass index subgroups. The Mercy and PAWPER XL-MAC methods performed acceptably in non-obese adults. CONCLUSION: The ideal weight estimation method should be accurate, rapid, simple, and feasible. This study has demonstrated the accuracy of 7 methods. The Lorenz method performed best but is complex and likely to be difficult to apply in resuscitation settings. Other simpler and quicker methods are at least as accurate as the best methods widely used in children, and there is potential for further calibrating these for use in adults before validation in real-world studies.

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.

Impact of ultrasound on management for dyspnea presentations in a Rwandan emergency department.

BACKGROUND: The complexity of diagnosis for critically ill dyspnea presentations in the emergency department remains a challenge. Accurate and rapid recognition of associated life-threatening conditions is paramount for timely treatment. Point-of-care ultrasound (POCUS) has been shown to impact the diagnosis of dyspnea presentations in resource-rich settings, and may be of greater diagnostic benefit in resource-limited settings. METHODS: We prospectively enrolled a convenience sample of 100 patients presenting with dyspnea in the Emergency Department at University Teaching Hospital of Kigali (UTH-K) in Rwanda. After a traditional history and physical exam, the primary treating team listed their 3 main diagnoses and ranked their confidence accuracy in the leading diagnosis on a Likert scale (1-5). Multi-organ ultrasound scans performed by a separate physician sonographer assessed the heart, lungs, inferior vena cava, and evaluated for lower extremity deep vein thrombosis or features of disseminated tuberculosis. The sonographer reviewed the findings with the treating team, who then listed 3 diagnoses post-ultrasound and ranked their confidence accuracy in the leading diagnosis on a Likert scale (1-5). The hospital diagnosis at discharge was used as the standard in determining the accuracy of the pre- and post-ultrasound diagnoses. RESULTS: Of the 99 patients included in analysis, 57.6% (n = 57) were male, with a mean age of 45 years. Most of them had high-level acuity (54.5%), the dyspnea was of acute onset (45.5%) and they came from district hospitals (50.5%). The most frequent discharge diagnoses were acute decompensated heart failure (ADHF) (26.3%) and pneumonia (21.2%). Ultrasound changed the leading diagnosis in 66% of cases. The diagnostic accuracy for ADHF increased from 53.8 to 100% (p = 0.0004), from 38 to 85.7% for pneumonia (p = 0.0015), from 14.2 to 85.7% for extrapulmonary tuberculosis (p = 0.0075), respectively, pre and post-ultrasound. The overall physician diagnostic accuracy increased from 34.7 to 88.8% pre and post- ultrasound. The clinician confidence in the leading diagnosis changed from a mean of 3.5 to a mean of 4.7 (Likert scale 0-5) (p < 0.001). CONCLUSIONS: In dyspneic patients presenting to this Emergency Department, ultrasound frequently changed the leading diagnosis, significantly increased clinicians' confidence in the leading diagnoses, and improved diagnostic accuracy.

Agreement between capillary and venous lactate in emergency department patients: prospective observational study.

OBJECTIVES: Capillary blood lactate testing with handheld analysers has great advantages to reduce the time needed for clinical decisions, and for extended use in the prehospital setting. We investigated the agreement of capillary lactate measured using handheld analysers (CL-Nova and CL-Scout+ measured by Nova and Lactate Scout+ analyzers) and the reference venous level assessed using a point-of-care testing (POCT) blood gas analyser (VL-Ref). DESIGN: A prospective observational study. SETTING: A university teaching hospital emergency department in Hong Kong. PARTICIPANTS: Patients triaged as 'urgent' (Category 3 of a 5-point scale), aged ≥18 years during 2016 were eligible. 240 patients (mean age 69.9 years) were recruited. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome measure was the agreement of the capillary blood lactate level measured by handheld lactate analyser when compared with the reference standard technique, namely venous blood samples obtained by venepuncture and analysed using the blood gas analyser. The secondary outcome measure was the difference in values of venous lactate using blood gas analysers and handheld lactate analysers. RESULTS: The results of VL-Ref ranged from 0.70 to 5.38 mmol/L (mean of 1.96 mmol/L). Regarding capillary lactate measurements, the bias (mean difference) between VL-Ref and CL-Scout+ was -0.22 with 95% limits of agreement (LOA) of -2.17 to 1.73 mmol/L and the bias between VL-Ref and CL-Nova was 0.46, with LOA of -1.08 to 2.00 mmol/L. For venous lactate, results showed the bias between VL-Ref and VL-Scout+ was 0.22 with LOA being -0.46 to 0.90 mmol/L, and the bias between VL-Ref and VL-Nova was 0.83 mmol/L with LOA -0.01 to 1.66 mmol/L. CONCLUSION: Our study shows poor agreement between capillary lactate and reference values. The study does not support the clinical utility of capillary lactate POCT. However, venous lactate measured by Scout+ handheld analyser may have potential for screening patients who may need further testing. TRIAL REGISTRATION NUMBER: NCT02694887.

Estimating children's weight in a Rwandan emergency centre.

INTRODUCTION: Most drugs, fluids and ventilator settings depend on the weight of a paediatric patient. However, knowledge of the weight is often unavailable as the urgency of the situation may impede measurement. The most common methods for paediatric weight estimation are based on height or age. This study aimed to compare the accuracy of various weight estimation methods and to derive a dedicated age-based tool within a Rwandan setting. METHODS: This was a retrospective study using age, weight and height data from randomly selected charts of Rwandan children, aged between one and ten years, who attended the paediatric emergency centre, Centre Hospitalier Universitaire de Kigali, Rwanda. Weights were estimated using four versions of the Broselow Tape and several age-based formulae. Linear regression was used to derive a new age-based weight estimation formula, the Rwanda Rule. Weight estimations were then compared with actual weight using Bland-Altman analysis, and the proportions of estimates within 10 and 20% of actual weight. RESULTS: There were 327 children included in the study. The derived Rwanda Rule was: weight (kg) = [1.7 × age (years)] + 8. This formula and the original Advanced Paediatric Life Support formula (weight = [2 × age] + 8) performed similarly. Both were better than other age-based formulae (69% of estimates within 20% of actual weight). All editions of the Broselow Tape performed better than age-based rules. The 1998 version performed best with 84.8% of estimates within 20% of actual weight. DISCUSSION: This study is the first to compare paediatric weight estimation methods in Rwanda. Locally, and until we have evidence from further research that other methods are superior, we would advise use of the 1998 Broselow Tape in children aged one to ten years old. Where the Broselow Tape is not available, the original Advanced Paediatric Life Support formula should be used.

An unusual cause of recurrent laryngospasm: A case report.

INTRODUCTION: Laryngospasm is a partial or complete closure of the vocal cords, causing stridor and then complete airway obstruction. We present an unusual case of recurrent laryngospasm following cervical spine trauma. CASE REPORT: A 41-year-old pedestrian was hit by a car sustaining several spine fractures including a comminuted fracture of C1. These were initially unrecognised, and his cervical spine was not immobilised. During this time the patient experienced three episodes of laryngospasm requiring intubation. On day 11 his fractures were identified, and a Philadelphia collar was placed. He made a full recovery without any neurological sequelae. DISCUSSION: Laryngospasm is a recognised complication of anaesthesia and intubation. This case illustrates that this life-threatening complication can also follow cervical fractures, and reinforces the need for prompt and careful review of imaging to identify such fractures in trauma patients, especially those with stridor.

Major incident simulation in Rwanda: A report of two exercises.

INTRODUCTION: Healthcare systems must be equipped to handle major incidents. Few have been described in the African setting, including in Rwanda. The purpose of this case report was to describe and discuss two major incident simulations in Rwanda with different challenges. CASE REPORT: We report two recent major incident exercises conducted in Rwanda, in 2017. The exercises exemplify two different types of multiple casualty incidents requiring the deployment of extra-ordinary resources, one due to the location of the incident (off-shore), and the other due to the large volume of casualties. Both exercises required extensive multi-agency planning and training beforehand, as part of an increasing awareness of the need for preparedness for these types of incidents. CONCLUSION: The exercises demonstrated the need for a standardised, physiological method of triage based on clinical needs; this is in order to maximise the number of lives saved. Triage training should be an integral part of further major incident exercises, which should be conducted regularly.

Oral paracetamol and/or ibuprofen for treating pain after soft tissue injuries: Single centre double-blind, randomised controlled clinical trial.

BACKGROUND: Soft tissue injuries commonly present to the emergency department (ED), often with acute pain. They cause significant suffering and morbidity if not adequately treated. Paracetamol and ibuprofen are commonly used analgesics, but it remains unknown if either one or the combination of both is superior for pain control. OBJECTIVES: To investigate the analgesic effect of paracetamol, ibuprofen and the combination of both in the treatment of soft tissue injury in an ED, and the side effect profile of these drugs. METHODS: Double-blind, double dummy, placebo-controlled randomised controlled trial. 782 adult patients presenting with soft tissue injury without obvious fractures attending the ED of a university hospital in the New Territories of Hong Kong were recruited. Patients were randomised using a random number table into three parallel arms of paracetamol only, ibuprofen only and a combination of paracetamol and ibuprofen in a 1:1:1 ratio. The primary outcome measure was pain score at rest and on activity in the first 2 hours and first 3 days. Data was analysed on an intention to treat basis. RESULTS: There was no statistically significant difference in pain score in the initial two hours between the three groups, and no clinically significant difference in pain score in the first three days. CONCLUSION: There was no difference in analgesic effects or side effects observed using oral paracetamol, ibuprofen or a combination of both in patients with mild to moderate pain after soft tissue injuries attending the ED. TRIAL REGISTRATION: The study is registered with ClinicalTrials.gov (no. NCT00528658).