Inhaled foreign bodies

A child with a cough or a wheeze is commonplace in PAUs and emergency departments in winter, but when should you be worried that a simple cough could be something more sinister?

Archie, a 2-year-old, presents to ED with a 24-hour history of coughing. It started when his mum was in the kitchen making baked beans on toast. He has a dry cough and is working hard with his breathing. His mum said he was playing on his mat when she heard him coughing away, but all seemed well after 5 minutes of consoling him. Since then, he has started coughing more, so she brought him in.

Why do inhaled foreign bodies matter?

Airway obstruction and death from aspirated foreign bodies (AFBs) are more common in infants and younger children because they have small calibre airways. Long-standing foreign bodies are associated with considerable morbidity. Early diagnosis remains the key to management.

The challenge starts from the get-go. There may be a vague history of coughing or shortness of breath, or they may be peri-arrest in resus. Inconsistent presentations mean you should have a high index of suspicion for an inhaled foreign body. Collateral history from a parent or babysitter is essential and may be life-saving. The run-up to the presentation may give you all the answers you need in a well-appearing child.

A nuanced history and exam may make the difference between getting the ENT consultant out of bed at 3 AM or sending the child home. Age is the most significant risk factor due to the inability to chew properly. This, coupled with a two-year-old’s propensity for trouble and natural curiosity, can spell disaster!

Keep the inhaled foreign body in your differential. This allows a holistic approach to the patient, especially with complex medical problems like cerebral/bulbar palsy and impaired swallow reflex.

How useful are x-rays in suspected foreign body aspiration?

Things get slightly tricky with Archie. You need to convince a 2-year-old to hold his breath and take deep breaths in and out. This is no mean feat at 2 AM. 

The x-ray should, ideally, be done in expiration. In smaller children, gently press on their upper abdomen to encourage this. The normal lung may seem denser and smaller than the affected lung. The foreign body creates a ball valve as air cannot get past the foreign body. This causes hyperinflation of the lungs and depression of the hemidiaphragm. You may also see a radiolucent foreign body. Remember, though, that 40% of X-rays may be normal.

What next?

So, you’ve found an aspirated foreign body or strongly suspect it. What should you do next? This will very much depend on where you work. The first port of call should be ENT and the anaesthetic team. If you have respiratory specialists on-site, they may also need to be involved. You may have to talk to your local retrieval service if such services are unavailable.

How do aspirated foreign bodies cause problems?

A purely metallic object causes minimal chemical irritation and can cause a mechanical blockage.

Conversely, things like peanuts (which are lipophilic) can cause massive cytokine release and inflammation due to their fat content. In addition, a starch-rich food may expand due to water retention, potentially turning a partial obstruction into a complete. Never leave a peanut in an airway overnight. It will not end well! (based on personal experience of crash ECLS!)

They can be removed either by rigid bronchoscopy (large metal tube in the trachea) if it hasn’t slipped in too far, or flexible bronchoscopy (for smaller objects) or bronchoalveolar lavage.

The literature is conflicted about antibiotics. A small retrospective study in 2018 of 34 patients who underwent rigid laryngobronchoscopy to retrieve an aspirated foreign body found that just under half (44%) had a secondary bacterial infection. The two most common organisms were Streptococcus pneumoniae and Haemophilus influenza. The evidence for or against is mixed, with most of it being more than 20 years old. The more recent evidence suggests sending samples for culture and then reviewing the results.

Take home points

There needs to be increased awareness of the perils of aspirated foreign bodies. This highlights the importance of the therapeutic relationships which GPs have with their patients and their families, putting them in a unique, informative role within the local community.

During the COVID pandemic, we spent more time at home and with our families. It can be exhausting keeping children entertained, so don’t be quick to judge a moment of inattention.

Aspirated foreign bodies are common and are potentially life-limiting diagnoses. Having this in the back of your mind and having a structured way of assessing these children is critical in the timely diagnosis and treatment of an otherwise under-reported diagnostic challenge.

You ask a few more questions, examine Archie and listen to his chest. He has reduced air entry on the right with increased work of breathing.

You request a chest x-ray, and you notice right-sided changes and a radio-opaque foreign body. You ring ENT and Respiratory to review.  In theatre, they retrieve a small piece of Lego from his right main bronchus. He recovers well and is home the next day. 

Many thanks to Dr P Nagakumar and the respiratory team at Birmingham Children’s Hospital for their support and guidance.

References

Gruber M, van Der Meer G, Ling B, Barber C, Mills N, Neeff M, Salkeld L, Mahadevan M. The bacterial species associated with aspirated foreign bodies in children. Auris Nasus Larynx. 2018 Jun;45(3):598-602. doi: 10.1016/j.anl.2017.07.014. Epub 2017 Aug 2. PMID: 28779997.

https://www.rch.org.au/clinicalguide/guideline_index/Foreign_bodies_inhaled/

Salih AM, Alfaki M, Alam-Elhuda DM. Airway foreign bodies: A critical review for a common pediatric emergency. World J Emerg Med. 2016;7(1):5-12. doi:10.5847/wjem.j.1920-8642.2016.01.001