Foreign body aspiration continues to be a common problem in paediatrics that may have severe consequences, as it can result in both acute and chronic health problems. Aspiration usually becomes a medical emergency that requires a prompt diagnosis and an urgent approach to its management. Unfortunately, it may not only result in immediate death, but in some cases it can also cause severe brain injury due to hypoxia.1

In other cases, foreign body aspiration may cause chronic respiratory disease, producing atelectasis, pneumonia, bronchiectasis, etc.2,3

Consequently, it is important to promote a series of prevention and intervention measures in the general population to address suspected mechanical obstruction of the airways. Educating and raising awareness adequately in the population is essential to prevent foreign body aspirations; parents must be made aware of the significant risk of aspiration and its high incidence in young children, and be acquainted with basic measures for its prevention.4–6

We should not forget that choking on a foreign body accounts for 40% of unintentional deaths in infants aged less than 1 year, and that the prevalence of hypoxic encephalopathy secondary to bronchial aspiration is also substantial.

Episodes of foreign body aspiration usually happen in children aged less than 5 years, and the majority occur in patients aged less than 3 years (due to the absence of adequate teeth and immaturity in the coordination of swallowing). It is the second leading cause of death at home in children aged 1–3 years.7,8

A review study by Jaswal and Jana9 referenced a 1995 study by Darrow and Holinger. After analysing multiple case series, these authors found that 84% of episodes occur before age 5 years and 73% before age 3 years. Of all episodes, 56.4% occurred in the 1–3 year group, and they underscored that there was an incidence of 6% in infants aged less than 1 year.

Other authors have also found a second incidence peak at 8–11 years of age with somewhat different characteristics (for example, aspirated objects tend to be of a different kind, for example, nonfood items).10,11

When it comes to the distribution by sex, foreign body aspirations are slightly more frequent in males, as evinced in several studies.1,9,12,13

As for the setting of aspiration episodes, most take place at home, and most cases of suffocation occur while the child is eating or playing, usually in the presence of another person.10

We ought to underscore the lack of awareness regarding this issue in households and even in schools. Thus, for example, it is typical for some nurseries and schools to celebrate “chestnut” or “nut” parties with the arrival of autumn that are meant for children to learn about, try and also become exposed to these foods. Needless to say, the presence of these foods in all types of celebrations, including birthday parties, is the norm.1

As for the nature of the foreign body, and in Spain in particular, the items that are involved most frequently (60–80% of cases) are vegetables, nuts and seeds (especially peanuts and sunflower seeds). Other foods and a variety of inorganic objects (usually toy parts, balloons, pebbles, etc.) are involved less frequently.1–6,14 In this regard, a study conducted in the United States that analysed 17537 episodes of nonfatal choking in children aged less than 14 years found that 59.5% were food-related, 31.4% nonfood-related, and the cause of 9.1% was unknown.12

When it comes to nonfood items, we ought to highlight very small objects (balls, marbles, springs, pins, etc.), and especially balloons, which adhere and conform to the shape of the airways and can lead to total obstruction (29% of fatalities due to nonfood-related choking involve balloons), something that can also happen with latex gloves.10

In terms of the location of the aspirated bodies, these are found most frequently in the right main bronchus, although the evidence shows that the difference in frequency between both main bronchi (right and left) is not as marked as in adults.

Different case series of children published in the literature have reported a proportion of foreign bodies found in the right main bronchus ranging between 48.6% and 55%, which differs from the distribution in adults, in whom this location is found in 65–70% of cases.1,2,7,11,15

The true incidence of choking due to foreign body aspiration is actually not known, as most episodes resolve spontaneously without medical attention.10–13 In Spain, the incidence of episodes for which care is sought at the hospital is approximately 15 per 100000 inhabitants aged less than 14 years, and food-related episodes are the most frequent type.1 This incidence has remained stable through the years despite the measures undertaken, although there is variability between countries based on life style (celebrations and parties) and dietary habits.14–16

Health education and the various preventive measures that have been implemented in relation to the manufacturing and labelling of toys and other objects that are part of children's lives, as well as compliance with pertinent regulations, have contributed to controlling the number of choking events, at least when it comes to nonfood foreign objects.

Still, the analyses performed by the European Child Safety Alliance17 show that while things have improved in Spain in recent years, there is still much left to do when it comes to implementing measures for preventing this type of accidents.

Foreign body aspiration at any level of the respiratory tract has, as we have explained, a considerable impact due to its frequency, severity, potential sequelae and of course the associated mortality, as reflected in various studies.

When it comes to mortality, it is believed that foreign body aspirations are responsible for 7% of all unintentional fatalities in children aged less than 4 years, and they caused 300 deaths in the United States in 1991 and 160 in 2001.2–7 In the United States, prior to the standardisation of bronchoscopy, the estimated mortality was 50%. Following improvements in endoscopic and anaesthetic materials and techniques, mortality has declined to nearly 1%.2,4,18 Nevertheless, it is estimated that in the United States, choking on food causes the death of one child every five days.12

We have also succeeded in decreasing mortality in Spain. In our country, mortality has been estimated to amount to 0.9% of the aspiration cases that are managed at the hospital level, a figure that is similar to that reported by other authors.1 Unfortunately, this should be considered an underestimation of the overall percentage, as cases that result in death prior to reaching the hospital are not usually included in the calculation.

In addition to technical improvements, decreases in mortality have also been achieved through the introduction of practice protocols, specifically through the clinical assessment of patients, the awareness of the problem of health care providers, and the indications for bronchoscopy (secondary prevention).10

The family's suspicion of foreign body aspiration, respiratory manifestations, auscultation and chest radiography are the main factors that lead to bronchoscopic examination and to the resolution of the problem. The strongest indication among these factors is the family's suspicion of an aspiration event.18,19 In fact, the clinical datum with the highest sensitivity and specificity is a history of choking, although the absence of such an episode does not rule out the possibility of aspiration; it has been described that in up to 20% of cases, parents did not witness or disregarded the choking episode.18,19

Data from the Instituto Nacional de Estadística (National Institute of Statistics)20 show that the overall mortality due to unintentional injury has been decreasing in the last 15 years, especially for road traffic accidents. However, the mortality due to foreign body aspiration has remained more or less stable during this period.

Preventive measures, especially at the primary care level, and strategies based on education and policy-making remain to be implemented in Spain, as can be gleaned from the data obtained by the European Child Safety Alliance.

Among other measures, this institution recommends policies requiring that warning labels include specific descriptions of the danger, which would be more effective than policies not requiring specific warnings. Furthermore, it considers that legislation is more effective when it is supported by educational interventions.

The modification of products by means of legislation permanently eliminates a greater proportion of the risk of choking or strangulation than parental supervision, and is recommended for the safe design of cribs and carrycots and other products that carry a risk of child suffocation.21

Legislation mandating that warning labels in products include a specific description of the hazard is more effective than legislation that does not require warnings to be specific.21,22

Another useful strategy is the enactment of policies banning unsafe products.21,23

The authors have no conflict of interests to declare.