Arjun Rao: Sepsis at DFTB17

Cite this article as:
Team DFTB. Arjun Rao: Sepsis at DFTB17, Don't Forget the Bubbles, 2018. Available at:
https://doi.org/10.31440/DFTB.15246

This talk was recorded live on the second day at DFTB17 in Brisbane. If you missed out in 2017 then why not book your leave for 2018 now. Tickets are on sale for the pre-conference workshops as well as the conference itself at www.dftb18.com.

Steroids for pre-school wheeze

Cite this article as:
Tessa Davis. Steroids for pre-school wheeze, Don't Forget the Bubbles, 2018. Available at:
https://doi.org/10.31440/DFTB.14563

Wheeze must be one of the most common paediatric presentations to the emergency department and up till now most of us have been reassuring parents and sending them away without treatment. But should we be doing more?  A paper, released just last week, suggests that we could.

Simon Craig: Acute asthma at DFTB17

Cite this article as:
Team DFTB. Simon Craig: Acute asthma at DFTB17, Don't Forget the Bubbles, 2017. Available at:
https://doi.org/10.31440/DFTB.13122

This talk was recorded live at DFTB17 in Brisbane. We’ve got plenty more where this one came from so keep on checking in with us every week. If you think you’ve got the chops to pull it off next year then get in touch with us hello@dontforgetthebubbles.com.

The 8th Bubble Wrap

Cite this article as:
Grace Leo. The 8th Bubble Wrap, Don't Forget the Bubbles, 2017. Available at:
https://doi.org/10.31440/DFTB.12183

With millions upon millions of journal articles being published every year it is impossible to keep up.  Every month we ask some of our friends from the world of paediatrics to point out something that has caught their eye.

Through the looking glass

Cite this article as:
Andrew Tagg. Through the looking glass, Don't Forget the Bubbles, 2016. Available at:
https://doi.org/10.31440/DFTB.9685

As we head out winter in the southern hemisphere the northern hemisphere can see that ‘Winter is Coming’ and with it the scourge of the paediatric emergency departments – bronchiolitis.  It’s one of those diseases that the we should all be able to spot but the real challenge is picking up those that present as if they have bronchiolitis but in fact have a different disease entity altogether. 

Asthma for ambos HEADER

Asthma for Ambos

Cite this article as:
Andrew Tagg. Asthma for Ambos, Don't Forget the Bubbles, 2016. Available at:
https://doi.org/10.31440/DFTB.9592

Tonight I had the privilege to talk to the team at the Werribee branch of Ambulance Victoria. I was given the brief to talk on something to do with paediatric respiratory problems so I thought I would focus on one of their most common presentations – asthma.

Asthma is a common condition and affects one in ten Australians. Approximately 17.2% of all kids in Victoria have been diagnosed with it. The incidence in Aboriginal or Torres Strait Islanders is higher at around 20%. Whilst a large number of these will never need to go to hospital, of those that do go, 43% per cent need admission. This is much higher than their adult counterparts. A large number can be safely managed at home with their pre-written asthma action plan (though only 41% of kids under 15 years of age have one) but some children are more at risk of critical or life-threatening asthma than others. Fortunately, the death rate in the under 15-year-old sub-population is around 0.2 per 100,00 people.

Risk factors for a more severe attack include:-

  • A previous severe asthma attack requiring an ICU admission
  • Two or more hospital stays because of asthma in the last year
  • Use of more than two reliever inhalers in the last month
  • Exposure to tobacco smoke
  • Previous allergic rhinitis, food allergies or hay-fever

There is a seasonal peak in ED visits in late summer and autumn for children, whereas more adults present in the winter. This may possibly be due to the increased incidence of viral upper respiratory tract infections among grown-ups at this time of year.

Some people are more likely to call an ambulance than others. They include those with :-

  • Poor knowledge about asthma
  • No asthma action plan
  • Poor self-management skills
  • Limited access to primary care

Paramedics are very experienced in managing it because asthma is such a common condition. I want to focus on some areas where what should happen and what does happen might diverge.

Myth – Oxygen saturations are useful in the management of asthma

An acute attack is characterised by bronchospasm, coupled with mucosal oedema and hypersecretion of mucus. This leads to aV/Q mismatch as there is hypoxic vasoconstriction and decreased blood flow to the under-ventilated lung in order to match pulmonary perfusion with alveolar ventilation.

In the hospital setting, oxygen saturations of less than 91% may predict the need for prolonged bronchodilator therapy.

Hypoxaemia and hypocarbia only occur in the presence of life-threatening asthma. If you take into account the haemoglobin-oxygen dissociation roller-coaster it is easy to see how many children may teeter on the precipice of collapse before critical desaturation occurs. Whilst low oxygen saturations mean that a patient is unwell it should be clinically obvious at this point.  On the flip side, normal oxygen sats do not mean the patient is fine.  There is a concern that oxygen administration may lead to a delay in recognising clinical deterioration. Low oxygen saturations may also represent a degree of mucus plugging that may be helped with repositioning.

Hyperoxia can lead to absorption atelectasis as well as intra-pulmonary shunting with a subsequent reduction in cardiac output. As the 78% nitrogen in the alveoli gets washed out with increasing amounts of supplemental oxygen, tt is resorbed. This leads to a reduction in alveolar volume and collapse.

Myth – Nebulizers are better than spacers

A recent Cochrane review comparing nebulizers with spacers found that there was no real difference in hospital admission rate with either mode of delivery. Lung function tests and oxygen saturations were also unaffected by the mode of medication delivery. What was different, however, was the adverse effect profile. If you used a nebulizer you were much more likely to see tremor and tachycardia.

Old British Thoracic Society guidelines suggested using up to 50 puffs of salbutamol via spacer but this is probably a bit excessive.  The current recommendation is that 400mcg of salbutamol via spacer is probably equivalent to 2.5mg via nebulizer.

So do you know how to use a spacer? I took the Werribee team through the procedure.  If you are not sure then take a look at this great instructional video from Asthma Australia:-

Whilst spacers are cheap, those of you with the MacGyver instinct may want to make your own.

These jerry rigged spacers have certainly been shown to be as effective as conventional devices in resource poor settings.

Myth – You can never give enough salbutamol

Inhaled B2 agonists relieve bronchospasm and improve oxygenation.  The minor side effects that we have all seen include tremor, anxiety, headache, dry mouth and palpitations. If given, without oxygen, they have also been shown to cause or worsen hypoxaemia. Pulmonary vasodilation leads to a worsening ventilation-perfusion mismatch.

Inhaled salbutamol may also cause metabolic acidosis even when the mechanical work of breathing has been improved with paralysis and ventilation this still occurs. In the non-paralysed patient, the body compensates for this acidosis by increasing the respiratory rate to blow off the CO2. Be mindful that the tachypnoea in your asthmatic patient may be due to excess beta-agonist and not their asthma.

So how does one recognise potential salbutamol toxicity in the pre-hospital setting? Consider it in all children who are wheezy, restless, tachycardic and have had large doses of beta-agonist.

Normal doses of inhaled salbutamol have been shown to cause hypokalaemia but the clinical significance of this is unknown. Hypokalemia, coupled with worsening respiratory and metabolic acidosis can have catastrophic cardiac effects.

Myth – Adrenaline is dangerous in asthma

One of the most most obvious reasons for using adrenaline in the setting of apparent severe or life threatening asthma is that the diagnosis may be in doubt.  Asthma and atopy often co-exist. Patients with known food allergies and asthma are much more likely to die due to anaphylaxis than those without asthma.  A child with severe anaphylaxis may initially have no more signs than a wheeze and worsening air hunger that is mistakenly treated as asthma. The diagnosis of anaphylaxis should be considered in all who fail to respond to initial therapy.

Nebulized adrenaline may be helpful in acute asthma via direct beta adrenoceptor mediated bronchodilatation. It is possible that there are also some alpha effects via reduction in localized oedema and reduction in microvascular leakage. Small studies have shown no difference between nebulized adrenaline and nebulized salbutamol in terms of increased peak expiratory flow. The may also be less of a drop off in PaO2 due to the V/Q mismatch seen with salbutamol use due to alpha action.  In younger children, bronchospasm may be less of an issue than mucosal oedema.
Remember all inhaled therapies are ineffective if they don’t go anywhere. If the child is so tight that they can barely inhale then salbutamol or nebulized adrenaline are likely to be of benefit and so alternative route should be sought.  IM adrenaline can be given quickly to the critically ill asthmatic whilst IV access is obtained.  At the time of writing a clinical trial into the potential benefit of IM adrenaline as an adjunct to inhaled B2 agonists is recruiting in the US

Myth – If the child is wheezing, they have asthma

Around 17% of infants experience wheeze with the first three years of life. Not all of these end up with a diagnosis of asthma. By the age of 4-5 the incidence of wheeze is around 21.7% which is almost double the incidence of asthma (11.5%) in this population. By the school years, the incidence of wheeze and asthma are near identical.
Wheeze is characterized by “a continuous whistling sound during breathing that suggests narrowing or obstruction in some part of the respiratory airways.” With that definition in mind, there are a number of clinical entities that may cause a wheeze. There is a grey area between those children with obvious asthma and obvious bronchiolitis. Whilst bronchodilators would be appropriate in asthma a large Cochrane review found them to be ineffective in bronchiolitis.  Most clinicians would give a one-off trial of salbutamol as long as it did not interfere with other management.  There is also no evidence of benefit for the use of systemic corticosteroids in pre-school wheeze.  Other potential diagnoses to consider include inhaled foreign bodies, pneumonia or pneumonitis, tracheomalacia or complications of congenital conditions.

So the presence of wheeze does not guarantee that the child has asthma. It is also worthwhile mentioning that the absence of a wheeze does not rule it out either. If there is severe bronchospasm and mucosal oedema not enough air entry will occur to cause a wheeze

Selected References

Asthma in Australia: with a focus chapter on chronic obstructive pulmonary disease. 2011 Full text

Oxygen saturations are useful in the management of asthma

Mehta SV, Parkin PC, Stephens D, Schuh S. Oxygen saturation as a predictor of prolonged, frequent bronchodilator therapy in children with acute asthma. The Journal of pediatrics. 2004 Nov 30;145(5):641-5.

Inwald D, Roland M, Kuitert L, McKenzie SA, Petros A. Oxygen treatment for acute severe asthma. British Medical Journal. 2001 Jul 14;323(7304):98.

Helmerhorst HJ, Schultz MJ, van der Voort PH, de Jonge E, van Westerloo DJ. Bench-to-bedside review: the effects of hyperoxia during critical illness. Critical Care. 2015 Aug 17;19(1):1.

Nebulizers are better than spacers

Zar HJ, Brown G, Donson H. Are spacers made from sealed cold-drink bottles as effective as conventional spacers?. Western Journal of Medicine. 2000 Oct;173(4):253.

Castro-Rodriguez JA, Rodrigo GJ. β-Agonists through metered-dose inhaler with valved holding chamber versus nebulizer for acute exacerbation of wheezing or asthma in children under 5 years of age: a systematic review with meta-analysis. The Journal of pediatrics. 2004 Aug 31;145(2):172-7.

You can never give enough salbutamol

Tomar RP, Vasudevan R. Metabolic acidosis due to inhaled salbutamol toxicity: A hazardous side effect complicating management of suspected cases of acute severe asthma. medical journal armed forces india. 2012 Jul 31;68(3):242-4.

Yousef E, McGeady SJ. Lactic acidosis and status asthmaticus: how common in pediatrics?. Annals of Allergy, Asthma & Immunology. 2002 Dec 31;89(6):585-8.

Udezue E, D’Souza L, Mahajan M. Hypokalemia after normal doses of nebulized albuterol (salbutamol). The American journal of emergency medicine. 1995 Mar 31;13(2):168-71.

Starkey ES, Mulla H, Sammons HM, Pandya HC. Intravenous salbutamol for childhood asthma: evidence-based medicine?. Archives of disease in childhood. 2014 Jun 17:archdischild-2013.

Adrenaline is dangerous in asthma

Coupe MO, Guly U, Brown E, Barnes PJ. Nebulised adrenaline in acute severe asthma: comparison with salbutamol. European journal of respiratory diseases. 1987 Oct;71(4):227-32.

If the child is wheezing they have asthma

Ducharme FM, Tse SM and Chauhan B. Asthma 2: Diagnosis, management, and prognosis of preschool wheeze. Lancet. 2014. 383:1593-604.

Okpapi A, Friend AJ, Turner SW. Acute asthma and other recurrent wheezing disorders in children. American family physician. 2013 Jul;88(2):130-1.

Goldstein H, Tagg A, Lawton B, Davis T. Easing the wheeze. Emergency Medicine Australasia. 2015 Oct 1;27(5):384-6.

Gadomski AM, and Scribani MB. Bronchodilators for bronchiolitis. Cochrane Database of Systematic Reviews. 2014;6:CD001266

Whoop, Whoop, Hooray

Cite this article as:
Andrew Tagg. Whoop, Whoop, Hooray, Don't Forget the Bubbles, 2016. Available at:
https://doi.org/10.31440/DFTB.8344

Henry Goldstein wrote an excellent article on pertussis a few years ago.  With some interesting new data coming to press with regard to risk factors for complications of the disease we thought it might be worthwhile doing some spaced repetition.

“My childhood was full of deep sorrow – colic, whooping cough, dread of ghosts, hell, Satan, and a deity in the sky who was angry when I ate too much plum cake” – George Eliot

Although cases have been described as far back as the Middle Ages it wasn’t until 1906 when the organism, Bordetella pertussis, was isolated by Bordet and Gengou. Up to 16 million cases develop worldwide every year with the majority of cases being in the developing world. Australia reported around 10,000 cases in 2009. Data from 2013 suggests it caused at least 61,000 death worldwide though this is likely to be a gross underestimate. Pertussis is one of the leading causes of vaccine preventable deaths worldwide.

Incubation

B. pertussis is highly infectious with the majority of exposed household contacts becoming infected to various degrees. The incubation period is usually quoted as 4-21 days with the average being 7-10 days.

Prodrome

Before the harsh coughing begins there is often a couple of weeks of symptoms that could easily be mistaken for a viral upper respiratory tract infection. Children may have a runny nose and a very mild tickly cough. This is the catarrhal phase. The classic ‘whoop’ might not be hard until week three or four of the illness.

Clinical course

The classical presentation is of a patient that has paroxysms of coughing that terminates in an audible inspiratory ‘whoop’. Like most classical presentations we learn about in medicine this presentation is rarer than we think. Children may also present with a protracted cough, or forceful post-tussive vomiting. Parents often seek advice as their children have had a couple of courses of antibiotics with no improvement in cough. It’s not know as the ‘one hundred day cough’ for nothing.

People with pertussis (adults and children alike) are infectious from the beginning of the catarrhal stage through to the third week after the onset of the paroxysmal stage of coughing. They cease being infectious five days after a course of antibiotics.

Diagnosis

Other than a suspicious clinical picture, formal diagnosis is best made by performing PCR for Bordetella on a nasopharyngeal swab. Once the initial three weeks have past though, it becomes increasing difficult to culture and it may be necessary to use rising IgA titres to make the diagnosis though this does not affect management.

Treatment

A number of treatments have been posited including vitamin C injections.

“In 66 [of 81] cases… [we saw] reduction of lip cyanosis in coughing attacks…[disappearance of] attacks with breathing difficulty, vomiting and recurrence … also the number of cough attacks diminished. Patients became lively, had good appetite and the convalescence progressed very satisfactorily.” – Concerning the Vitamin C Therapy of Pertussis [Whooping Cough]: Otani, Klinische Wochenschrift, December 1936

Coughs last, on average, 16 days. A Cochrane review found no specific benefit of steroids, bronchodilators or immunoglobulins for the treatment of the cough. Over the counter remedies are unlikely to help and may potentially cause harm.  To hear more listen to this great rant from Dr Anthony Crocco. The only thing that may help (a little) is honey.  Take a listen to Ken Milne’s podcast SGEM #26 – Honey, Honey for more on this subject.

What about antibiotics? Well (in adults) they are recommended in the initial catarrhal phase to help reduce duration of infectivity but they don’t seem to have much effect after the disease has been hanging around for three weeks. Because of this they are not recommended beyond this time period.

If they are needed then macrolides such as erythromycin, azithromycin or clarithromycin are recommended. Azithromycin should be used in children less than one month of age as erythromycin use has been linked to an increased incidence of hypertrophic pyloric stenosis.

Complications

Pertussis is far from benign in unvaccinated infants. According to the CDC, in children under 1 that are not fully vaccinated:-

  • 1 in 4 (23%) get pneumonia
  • 1 in 100 (1.1%) will have convulsions
  • 3 out of 5 (61%) will have apneoic episodes
  • 1 in 300 (0.3%) will develop encephalopathy
  • 1 in 100 (1%) will die

In Winter’s retrospective analysis of US pertussis deaths in infants under 120 days old mortality was linked with:

  • Significantly low birth weight
  • Younger gestational age
  • Younger age at onset
  • Higher WBC and higher lymphocyte count

In those less severely affected it may still cause sub-conjuctival haemorrhages, rib fractures and loss of bladder control.

Post-exposure prophylaxis

So who should get antibiotics if exposed to a confirmed case of pertussis? Most guidelines recommend that the following groups of people receive antibiotic prophylaxis.  It’s not really to treat the illness but rather to halt the spread.

  • Pregnant mothers in the last month of gestation (WHY)
  • Members of a household that has an  infant that is not fully vaccinated
  • Healthcare workers and babies potentially exposed and in a newborn nursery environment

To be fully vaccinated the child must have three effective doses of pertussis vaccine given at least four weeks apart.

Prevention

Whilst childhood immunisation does prevent the majority of cases, individual immunity does appear to decrease with time so there has been an upswing in the number of older children and teenagers affected. Pertussis is a notifiable disease and over 70% of cases that are notified are in patients over the age of 15.

The current Australian immunisation schedule has pertussis vaccine being given as a part of the combined Diptheria, Tetanus, acellular Pertussis (DTaP) vaccine at two, four and six months of age. Other countries may have an alternative schedule. The child then receives a pre-school booster at 4 years old. Because of the waning immunity they should also receive a dose in their teenage years. An individual’s immunity to pertussis may well have disappeared by the time they reach adulthood so new parents, or grandparents living in a house with a newborn should be offered a booster.

 

HT to Tim Horeczko (@EMtogether) for the heads up regarding the latest data

 

References

Royal Children’s Hospital, Melbourne guidelines on Pertussis can be found here

Cherry JD. Historical review of pertussis and the classical vaccine. Journal of Infectious Diseases. 1996 Nov 1;174(Supplement 3):S259-63. full text here

Pertussis (Whooping cough) complications. (2015). Retrieved April 13, 2016, from https://www.cdc.gov/pertussis/about/complications.html

GBD 2013 Mortality and Causes of Death Collaborators. “Global, Regional, and National Age-Sex Specific All-Cause and Cause-Specific Mortality for 240 Causes of Death, 1990-2013: A Systematic Analysis for the Global Burden of Disease Study 2013.” Lancet 385.9963 (2015): 117–171. PMC. Web. 14 Apr. 2016.

Forsyth K, Plotkin S, Tan T, von König CH. Strategies to decrease pertussis transmission to infants. Pediatrics. 2015 Jun 1;135(6):e1475-82.

Hay AD, Wilson A, Fahey T, Peters TJ. The duration of acute cough in pre-school children presenting to primary care: a prospective cohort study. Family Practice. 2003 Dec 1;20(6):696-705

Winter K, Zipprich J, Harriman K, Murray EL, Gornbein J, Hammer SJ, Yeganeh N, Adachi K, Cherry JD. Risk factors associated with infant deaths from pertussis: a case-control study. Clinical Infectious Diseases. 2015 Oct 1;61(7):1099-106.

 

PAC conference – Long on High Flow Oxygen Therapy

Cite this article as:
Tagg, A. PAC conference – Long on High Flow Oxygen Therapy, Don't Forget the Bubbles, 2015. Available at:
https://dontforgetthebubbles.com/pac-conference-long-on-high-flow-oxygen-therapy/

We have teamed up with APLS to share the videos from their Paediatric Acute Care Conferences. These videos have never been open access before, so if you weren’t able to attend the conferences, then now’s your chance to catch up.

The PAC Conference is run each year by APLS and consists of presentations on a range of topics relevant to paediatric acute and critical care.

Early Budesonide for the Prevention of Bronchopulmonary Dysplasia

Cite this article as:
Henry Goldstein. Early Budesonide for the Prevention of Bronchopulmonary Dysplasia, Don't Forget the Bubbles, 2015. Available at:
https://doi.org/10.31440/DFTB.7859

Bronchopulmonary dysplasia (BPD) is a common outcome in premature neonates, from 85% in 22/40 infants, to about 33% of neonates born in the 27th week of gestation. This recent study, published in the NEJM trialled a potential new therapy to reduce BPD.

DFTB in EMA #3 – Easing the Wheeze

Cite this article as:
Henry Goldstein. DFTB in EMA #3 – Easing the Wheeze, Don't Forget the Bubbles, 2015. Available at:
https://doi.org/10.31440/DFTB.7662

The team at DFTB had our third article published in the series for Emergency Medicine Australasia Journal.

Wheezing children commonly present to the ED. Bronchiolitis, preschool wheeze and asthma are common causes of such presentations. It is important to note that the term ‘wheeze’ is frequently misused by parents to describe a number of respiratory noises, including transmitted upper airway sounds and stridor.[1] Wheeze is, in itself, a symptom manifested by ‘a continuous whistling sound during breathing that suggests narrowing or obstruction in some part of the respiratory airways’.[2] One British study reported that 29.3% of children have had a wheeze by the age of three, and 30% of preschoolers with recurrent wheeze are diagnosed with asthma by 6 years of age.[3, 4] This article briefly reviews the diagnosis and management of preschool wheeze, while considering recent guidelines on bronchiolitis and asthma.

Click here to read the full article – “Easing the wheeze.”

Reference:

Goldstein, H., Tagg, A., Lawton, B. and Davis, T. (2015), Easing the wheeze. Emergency Medicine Australasia, 27: 384–386. doi: 10.1111/1742-6723.12463

From Cradle to the Grave – ACEM Annual Scientific Meeting 2014

Cite this article as:
Andrew Tagg. From Cradle to the Grave – ACEM Annual Scientific Meeting 2014, Don't Forget the Bubbles, 2014. Available at:
https://doi.org/10.31440/DFTB.6476

This years Australasian College of Emergency Medicine Annual scientific meeting in Melbourne has attracted over 900 delegates from all over the world. With an overarching theme of “Back to the Future” a number of speakers have been looking back on the past year in emergency medicine literature and predicting what might be up and coming in the next five years.  Whilst there have been a number of wonderful speakers talking about all aspects of emergency medicine the second day had a number of sessions that would be of interest to those practicing paediatric emergency medicine as well as those clinicians working in mixed adult and paediatric departments.  Some of the talks have been recorded and will be available on the ACEM website in due course, but one of the talks, by Simon Craig of Monash Medical Centre, stood out.