Two studies this month report a correlation between ultrasound detected aorta/IVC ratio and dehydration in children presenting with diarrhoea and/or vomiting. In both studies the IVC diameter was measured in expiration and the aortic diameter in systole, using a transverse view in the subxiphoid area. Both used acute and post-discharge weight comparison to ascertain degree of dehydration.
The first study took place in Rwanda and a percent weight change between admission and discharge of greater than 10% was considered the criterion standard for severe dehydration. 52 children were included ranging in age from 1 month to 10 year. Vessel diameter measurements were inner wall to inner wall. The IVC-to-aorta ratio correlated significantly with percent weight change (r = 0.435, p < 0.001). Using the best ROC curve cutoff of 1.22, aorta/IVC ratio had a sensitivity of 93% (95% CI = 81% to 100%), specificity of 59% (95% CI = 44% to 75%), LR+ of 2.3 (95%CI=1.5to3.5), and LR– of 0.11 (95%CI=0.02to 0.76) for detecting severe dehydration. The same study did not find ultrasound assessment of inferior vena cava inspiratory collapse or the World Health Organization scale to be accurate predictors of severe dehydration in this same population of children.
Ultrasound Assessment of Severe Dehydration in Children With Diarrhea and Vomiting
Acad Emerg Med. 2010 Oct;17(10):1035-41
The second study took place in the USA. The subjects were considered to have significant dehydration if the weight loss was at least 5%. 71 were children were included. The area under the curve (AUC) was 0.73 (95% CI = 0.61 to 0.84). An IVC ⁄ aorta cutoff of 0.8 produced a sensitivity of 86% and a specificity of 56% for the diagnosis of significant dehydration. The positive predictive value was 56%, and the negative predictive value was 86%. Note this equates to an aorta/IVC ratio of 1.25, similar to that in the first study.
My rough-and-ready take home message from these two studies appears to be that an aorta/IVC ratio less than about 1.2 makes severe dehydration less likely in children with symptoms of gastroenteritis.
Use of Bedside Ultrasound to Assess Degree of Dehydration in Children With Gastroenteritis
Acad Emerg Med. 2010 Oct;17(10):1042-7
Tag Archives: paediatric
Propofol for kids in the ED
A systematic review of the use of propofol for paediatric procedural sedation (PPS) identified sixty studies and 17 066 published paediatric propofol sedations performed outside the operating theatre setting. The incidence of complications were: desaturation 9.3%, apnoea 1.9%, assisted ventilation 1.4%, hypotension 15.4%, unplanned intubation 0.02%, emesis post procedure 0.14%, laryngospasm 0.1% and bradycardia 0.1%. There are many confounding variables that influence the likelihood of these events: adjunct opiates, propofol dosing strategies and supplemental oxygen. These rates of minor adverse events are similar to that published for ED sedation with other sedation agents
There were no reported incidents of aspiration or emesis during sedation and there were no deaths associated with procedural propofol sedation. The authors conclude: “the published adverse event data for paediatric propofol sedation support its ongoing use in the ED for appropriately selected paediatric patients by experienced physicians who are able to provide advanced cardiorespiratory support.”
Review article: Safety profile of propofol for paediatric procedural sedation in the emergency department
Emerg Med Australas. 2010 Aug;22(4):265-86
Paediatric arrest outcomes
A study of out-of-hospital paediatric arrests in Melbourne gives some useful outcome data: overall, paediatric victims of out-of-hospital cardiac arrest survived to leave hospital in 7.7% of cases, which is similar to adult survival in the same emergency system (8%). Survival was very rare (<1%) unless there was return of spontaneous circulation prior to hospital arrival. Sixteen of the 193 cases studied had trauma, but the survival in this subgroup was not specifically documented.
Epidemiology of paediatric out-of-hospital cardiac arrest in Melbourne, Australia
Resuscitation. 2010 Sep;81(9):1095-100
AED Use in Children Now Includes Infants
From the new 2010 resuscitation guidelines:
For attempted defibrillation of children 1 to 8 years of age with an AED, the rescuer should use a pediatric dose-attenuator system if one is available. If the rescuer provides CPR to a child in cardiac arrest and does not have an AED with a pediatric dose-attenuator system, the rescuer should use a standard AED. For infants (<1 year of age), a manual defibrillator is preferred. If a manual defibrillator is not available, an AED with pediatric dose attenuation is desirable. If neither is available, an AED without a dose attenuator may be used.
Summary: Adult AEDs may be used in all infants and children if there is no child-specific alternative
Highlights of the 2010 American Heart Association Guidelines for CPR and ECC
Peripheral vasoactive infusions
It is often recommended that vasoactive agents are infused via central lines because of the risk of infiltration and tissue injury. The Children’s Hospital Boston transport team describe transport of 73 infants and children who were treated during interhospital transport with vasoactive medications via a peripheral intravenous line.
Median transport time was only 38 minutes (range 3[!!]-216) and median age was 1 (birth to 19) .
Dopamine monotherapy was given in 66 patients, adrenaline (epinephrine) monotherapy in 2, dobutamine plus phenylephrine in 1, dopamine and epinephrine in 3, and dopamine, dobutamine, and epinephrine in 1 patient.
In this retrospective study no patients developed infiltration or other complications related to peripheral vasoactive agents during interfacility transport. Eleven of the 73 patients, however, did develop infiltrates related to vasoactive infusion after arrival at the accepting institution; all infiltrates involved only minimal blanching and/or erythema, and all resolved without significant intervention and caused no lasting tissue injury. The risk of infiltration rose with increasing medication dose and duration of use.
Interesting that noradrenaline (norepinephrine) wasn’t used. This study is interesting but the overwhelming predominance of dopamine makes it hard to extrapolate this to European or Australasian practice.
The Use of Vasoactive Agents Via Peripheral Intravenous Access During Transport of Critically Ill Infants and Children
Pediatr Emerg Care. 2010 Aug;26(8):563-6
Paediatric Tube Cuff Pressures
A paediatric critical care transport service encountered elevated tracheal tube cuff pressures (>30 cmH20) in 41% of 60 consecutive care studied, and over 60 cmH20 in 30%. This measurement was taken on arrival at the bedside, not in flight.
Cuffed tubes are good, but we need to keep an eye on the pressures.
This is in keeping with the results of an adult study previously blogged on this site.
Endotracheal Tube Cuff Pressures in Pediatric Patients Intubated Before Aeromedical Transport
Pediatr Emerg Care. 2010 May;26(5):361-3
Bronchiolitis – not much works
A review article on bronchiolitis reminds us that there is little evidence to support any specific therapies. Bronchodilators, steroids, adrenaline (epinephrine), CPAP, heliox, mucolytics and leukotriene antagonists are all reviewed. Of these, inhaled 3% saline as a mucolytic has some promise in that studies show it to reduce length of stay in admitted patients by one day. CPAP has been shown to reduce pCO2 but evidence of further benefit may have been limited by a lack of adequately powered studies.
Current Therapies in Bronchiolitis
Pediatr Emerg Care. 2010 Apr;26(4):302-7
FV cannulation in kids: 60° abduction
An ultrasound study on infants and children under general anaesthesia evaluated the femoral vein with the patients’ legs at 30° and 60° of abduction and their hips externally rotated. Measurements were taken at the level of the inguinal crease and 1 cm below the crease.
Hip rotation with 60° leg abduction significantly decreased the overlap between femoral vein and femoral artery at the level of the inguinal crease in both infants and children.
The authors recommend the optimal place for femoral vein cannulation in paediatric patients seems to be at the level of the inguinal crease with 60° leg abduction and external hip rotation.
Ultrasonographic evaluation of the femoral vein in anaesthetised infants and young children
Anaesthesia. 2010;65(9):895–898
Finding the sick febrile kid
Finding children with serious illness among the multitudes who present with fever is the number one challenge in paediatric emergency medicine.
A two year prospective cohort study was conducted at the Children’s Hospital Westmead in Sydney to develop and test a multivariable model to distinguish serious bacterial infections from self limiting non-bacterial illnesses.
A standardised clinical evaluation that included mandatory entry of 40 clinical features was recorded by physicians on around 15000 febrile kids under age 5. Clinical, laboratory and radiological follow up was undertaken to identify one of three key types of serious bacterial infection (SBI): urinary tract infection, pneumonia, and bacteraemia.
7.2% had SBI – urinary tract infection 3.4%, pneumonia 3.4%, and bacteraemia 0.4%.
A diagnostic model was developed using multinomial logistic regression methods. Physicians’ diagnoses of bacterial infection had low sensitivity (10-50%) and high specificity (90-100%), whereas the clinical diagnostic model provided a broad range of values for sensitivity and specificity.
The authors suggest that a computer assisted diagnostic decision tool could be used to determine the likelihood of serious bacterial infection.
The strongest positive predictors of serious bacterial infection were a generally very unwell appearance, high temperature, chronic disease, and prolonged capillary refill time. For children with pneumonia, other predictors were coughing, difficulty breathing, abnormal chest sounds, and to a lesser extent tachypnoea, chest crackles, and tachycardia. For urinary tract infection, the presence of urinary symptoms was by far the strongest indicator, whereas for bacteraemia, tachycardia and crying were also strong indicators although an editorial points out that only 64 cases of bacteraemia occurred, so this last result should be treated with caution.
The accuracy of clinical symptoms and signs for the diagnosis of serious bacterial infection in young febrile children: prospective cohort study of 15 781 febrile illnesses
BMJ. 2010 Apr 20;340:c1594
Weight formula for kids
The traditional ‘APLS formula’ for weight estimation in children based on age (wt in kg = [age+4] x 2) is recognised as underestimating weight in ‘developed’ countries, with the degree of underestimation increasing with increasing age.
Several authors have attempted to derive a more accurate formula.
In the UK, the measured weights of over 93 000 children aged 1-16 who attended a paediatric emergency department were used to compare a previously derived formula (wt=3[age]+7) with the APLS formula.
The formula ‘Weight=2(age+4)’ underestimated children’s weights by a mean of 33.4% (95% CI 33.2% to 33.6%) over the age range 1–16 years whereas the formula ‘Weight=3(age)+7’ provided a mean underestimate of 6.9% (95% CI 6.8% to 7.1%); this latter formula remained applicable from 1 to 13 years inclusive.
The authors state: ‘The APLS formula has clearly become a victim of better nourished children. With a mean underestimate of more than 20% (nearly 40% at age 10 years), its place as a weight estimation tool is questionable…. To continue with an inaccurate formula with no evidence base cannot be considered good medical practice.’
Weight estimation in paediatrics: a comparison of the APLS formula and the formula ‘Weight=3(age)+7’
Emerg Med J. 2010 Jul 20. [Epub ahead of print]
A previous retrospective Australian study on over 70 000 paediatric ED attendances derived formulae for three different age ranges:
- For Infants < 12 months: Weight (kg) = (age in months + 9)/2
- For Children aged 1-5 years: Weight (kg) = 2 x (age in years + 5)
- For Children aged 5-14 years: Weight (kg) = 4 x age in years.
Make your Best Guess: An updated method for paediatric weight estimation in emergencies
Emerg Med Australas. 2007 Dec;19(6):528-34