Category Archives: Kids

Acute Paediatrics

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

Taming the Ketamine Tiger

A paper of great interest for those of us who spend a lot of time teaching the use of ketamine describes its history from initial synthesis in the early 1960s. Ketamine pioneer Edward F. Domino, M.D describes how it was first given to humans in 1964: ‘Our findings were remarkable! The overall incidence of side effects was about one out of three volunteers. Frank emergence delirium was minimal. Most of our subjects described strange experiences like a feeling of floating in outer space and having no feeling in their arms or legs.

Domino goes on to list interesting anecdotes in ketamine’s history, like how his wife came up with the term ‘dissociative anaesthetic’ and how physicians and their partners experimenting with ketamine in the 1970s tried communicating with dolphins, fell in love, and froze to death in a forest. The pharmacology of ketamine is described along with its effects on pain and even depression.
Taming the ketamine tiger.
Anesthesiology. 2010 Sep;113(3):678-84 Free Full Text

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

ETCO2 and ROSC

One for the ‘hardly surprising’ category….
A study of end-tidal CO2 during out-of-hospital adult and child cardiac arrest resuscitation showed a sudden rise in CO2 was associated with return of spontaneous circulation (ROSC), suggesting that witnessing this would be a good time for a pulse check. Data from the 59 patients who achieved ROSC are shown below, time zero being time of ROSC. There was no such observed rise in the 49 patients who did not achieve ROSC.

A Sudden Increase in Partial Pressure End-Tidal Carbon Dioxide (PETCO2) at the Moment of Return of Spontaneous Circulation
The Journal of Emergency Medicine, Vol. 38, No. 5, pp. 614–621, 2010

Etomidate in RSI – systematic review

A systematic review of 20 included studies comparing a bolus dose of etomidate for rapid sequence induction with other induction agents resulted in the following conclusion:
“The available evidence suggests that etomidate suppresses adrenal function transiently without demonstrating a significant effect on mortality. However, no studies to date have been powered to detect a difference in hospital, ventilator, or ICU length of stay or in mortality”
The Effect of a Bolus Dose of Etomidate on Cortisol Levels, Mortality, and Health Services Utilization: A Systematic Review
Ann Emerg Med. 2010 Aug;56(2):105-13

Brain tumours in kids

When might you suspect a brain tumour in a child who presents with, say, nausea and vomiting, or behavioural disturbance? A guideline has been produced which might prompt one to think of this important but often delayed diagnosis.

The diagnosis of brain tumours in children: a guideline to assist healthcare professionals in the assessment of children who may have a brain tumour Arch Dis Child. 2010 Jul;95(7):534-9