INTRODUCTION

Foreign body ingestion or aspiration is one of the most common emergencies in pediatric patients ¹. Severity depends on factors such as the type of the object: organic such as insects or seeds or inorganic such as toys, metal objects, plastics, etc., as well as the location and the time from aspiration to removal of the foreign body ². Foreign body aspiration is a frequent cause of morbidity and mortality in children, and it was the cause of 160 deaths and more than 17 thousand emergency department visits in children under 14 years of age in the United States during the year 2000 ³. In Spain, the incidence rate peaks at the first two years of life ⁴. A study in Brazil reported that 50% of cases occur between the first and third year of life, mostly in males ⁵. Furthermore, this same study showed that most children under three years of age aspirated organic foreign bodies (86%) while those older than three years of age aspirated inorganic foreign bodies more frequently (75%) ⁵. Similarly, a study in Switzerland reported that 68.3% of patients were between 1 and 3 years old, and 60% presented symptoms in the last 24 hours ⁶.

The time of removal of the foreign body obstructing the patient’s airway is one of the most important factors to be evaluated ^2,7. An article carried out in China ⁷ described a correlation between the retention time of the foreign body in the airway and the length of hospital stay (r= 0.189; p<0.001), which implies that the longer the removal time, the longer the hospital stay. However, a study by Hidaka et al. showed that there is no association between the time interval from the aspiration episode to the extraction bronchoscopy and a prolonged hospital stay ⁸.

In Peru, foreign bodies in tracheal and bronchial airways can be extracted by fibrobronchoscopy (flexible bronchoscopy) or rigid bronchoscopy, performed by a physician with experience in pediatric airway management ⁹ and familiar with pediatric endoscopic equipment. However, the scarcity of human resources (pediatric pulmonologist), materials and infrastructure; added to the characteristics of our referral system ¹⁰ represent important limitations in the care of this condition. This medical emergency requires specialized, timely and effective management, since the presence of complications increases as long as the foreign body remains in the airways ^2,9. Therefore, this study aimed to determine the association between the time of illness prior to extraction and post-extraction hospital stay.

MATERIALS AND METHODS

RESULTS

We reviewed 324 medical records of pediatric patients diagnosed with foreign bodies in the airway. These patients underwent extraction by fibrobronchoscopy and/or rigid bronchoscopy at the HEP in the city of Lima, Peru. Of these 324 medical records, 141 were excluded and 183 histories were included in the study (Figure 1).

Figure 1 Participant selection flowchart. 

Of the total number of pediatric patients included in the study, we found that according to their sociodemographic characteristics, 120 (65.6%) patients were male, with a median age of 2.4 years (IQR: 1.3-7). Most patients (80.3%) attended HEP by referral (Table 1). The most frequent symptom, among the clinical and management variables of the patient with a diagnosis of foreign body, was cough (73.2%). Finally, the most frequently used rescue maneuver prior to extraction was sweeping the mouth with the finger (37.2%) (Table 1).

According to the characteristics of the bronchoscopy performed on pediatric patients with a diagnosis of foreign body in the airways, we found that most patients had an illness time prior to bronchoscopy of less than or equal to two days (56.8%). Likewise, the most frequent location of the foreign body was the right bronchial tree (46.6%). The most frequent type of bronchoscopy was flexible bronchoscopy, as the initial technique (53.0%) and as the procedure that removed the foreign body (54.1%). The duration of bronchoscopy had a median of 20 minutes (IQR: 15-30) (Table 2).

Regarding the characteristics of the pediatric patients after foreign body removal, most (72.7%) were discharged early (before or equal to 24 hours). The predominant type of foreign body in pediatric patients was organic material (59.6%). As for complications, the most frequent was pneumonia (24.6%), followed by atelectasis (18.0%) and pneumothorax (1.6%), this being the least frequent complication (Table 3).

We found no differences between median patient age and post-extraction hospitalization time during bivariate analysis. Likewise, there were no differences between the proportions of previous hospitalization of patients with post-extraction hospitalization time. However, differences were found between the proportions of finger sweeping of the mouth as a rescue maneuver and post-extraction hospitalization time (Table 4). Additionally, differences were also found between the proportions of pre-bronchoscopy sick time and post-bronchoscopy discharge time (p<0.001). Finally, differences were found as well between the proportions of the occurrence of pneumonia and post-extraction hospitalization time (p<0.001) (Table 5).

During the multivariate analysis, the model adjusted for the variables age, sex, type of foreign body and mouth sweeping technique showed that the risk of having late discharge increases by 2.94 times (95% CI: 1.72-5.01; p=0.001) in those patients with more than 48 hours of sick time prior to extraction bronchoscopy (Table 6).

DISCUSSION

The most frequent location was in the right bronchial tree and the most frequent type of foreign body was organic materials among all 183 included patients. We found that 72.7% of patients were discharged before 24 hours. Our main finding was the association between the time of illness prior to bronchoscopy greater than two days and late discharge.

The moment of aspiration usually occurs while eating or playing, usually under adult supervision ¹⁷, which corresponds to the high exposure to new stimuli and foods at early ages, with organic objects being the most frequent ¹⁸, particularly food ¹⁹. This finding is consistent with another study by Bing Zhong et al. ¹⁶. Particularly, in our study, 59.6% of the foreign bodies removed were organic. This finding is relevant when considering that the type of foreign body is associated with the length of hospital stay ⁸, and that different types of foreign bodies can be associated with different types of injuries, for example, organic bodies are associated with upper respiratory tract injury ²⁰.

Our study shows an association between the time of illness prior to bronchoscopy and the time of hospitalization after foreign body extraction. However, the study by Hidaka et al. ⁸, found no association between the variables of interest; they described that 74% of the cases underwent removal within two days of foreign body aspiration, while in our study only 53.8% of the cases underwent removal within two days of foreign body aspiration. This difference would indicate that in other contexts such as Japan, the diagnosis and removal of the foreign body is performed in less time compared to our context, thus reducing the risk of complications and hospitalization time. Thus, our findings could be explained by the problems of the medical referral system in Peru and the low availability of specialists ¹⁰. Likewise, the study by Hidaka et al. describes a low prevalence of foreign body aspiration in Japan ⁸, since they only found 77 cases of foreign body aspiration during the 23 years they evaluated (from 1988 to 2011). In contrast, our study considered a time interval of only six years (from 2014 to 2019), finding more than 183 cases. Therefore, these differences could lead to dissimilar results between the two studies.

However, several studies found an association between the time of illness and the time of post-extraction hospitalization ^7,21. For example, a study conducted in China ⁷, reported a correlation between the time of foreign body retention in the airway and the time of hospitalization. Although this correlation was low (r=0.189), it was statistically significant (p<0.001). In our study, 56.8% of the participants had an illness time prior to bronchoscopy less than or equal to two days, a result similar to that reported in the study conducted in Chinese population, where 68.5% had a time of three days or less, which would mean that both studies found a relationship between both variables. However, it was not possible for the authors of the Chinese study to establish a cut-off point for the time of illness prior to bronchoscopy, as they considered this variable to be numerical. Additionally, another study performed in Spanish pediatric population showed a similar result to ours, where the authors report that there was a significant association between diagnostic delay and the appearance of long-term complications, without addressing intraoperative adverse events ²¹.

Prolonged illness prior to bronchoscopy doubles the risk of post-extraction hospitalization. Although asphyxia and cardiorespiratory arrest are more frequent shortly after aspiration, they can also occur in later days ²². Late diagnosis is frequently associated with atelectasis, lung abscesses and increased morbidity and mortality ^22-24, due to inflammation occurring at the lower airway level ¹⁶. In fact, medical literature describes that foreign body aspiration causes inflammation in the airway, which prolongs pulmonary recovery time ²⁵. The importance of this finding is evidenced in a study by Man Ki Chung et al. where they describe an association between inflammatory findings in the airway prior to foreign body removal and delayed pulmonary recovery ²⁵. This fact can cause the need for extended hospitalization, which in turn, results in a higher risk of acquiring nosocomial infections ²⁶.

The diagnostic or therapeutic delay can be explained by causes associated with the physician, resources, parents or uninformative medical records ²⁰. Regarding the medical records, the condition may occur even without a history of choking or asphyxia in the pediatric population ²⁷. For this reason, our results highlight the importance of timely management and correct evaluation of patients within the first 48 hours. As a complement, in order to ensure timely management and improve prognosis, it is recommended to train child caregivers, streamline referral systems and strengthen programs on the use of rigid and flexible bronchoscopy in pediatric patients. Therefore, in line with our findings, priority should be given to the availability of trained professionals and sufficient resources in health centers for the timely management of pediatric patients with foreign body aspiration, which would reduce complications and improve the prognosis of these patients.

This study has limitations. Patient evolution after discharge from HEP was not evaluated due to the nature of the study design. Although we only evaluated the data from the medical records, post-extraction complications are infrequent ^18,21,27,28 and if they had occurred, the patient would have opted to return. Since the data were collected manually by means of a data collection form, information bias may have occurred. In addition, we did not include other variables relevant to this study, such as the activity that the patient was performing at the time of aspiration, since this information is usually not recorded in the medical records. Regarding external validity, since the data were obtained from a single hospital, our results cannot be extrapolated to different populations. However, it should be considered that HEP is one of the main referral institutions for pediatric patients in Lima, Peru, which allows us to determine the association of interest in an exploratory manner. Finally, there is no standardization of the main variables (time of discharge and time of illness prior to bronchoscopy). Nevertheless, our research uses cut-off points described in similar studies ^14,15.

According to our results, most foreign body aspiration cases occurred in boys younger than three years old. In addition, patients with an illness time longer than two days between foreign body aspiration and bronchoscopy had 2.94 higher risk of a prolonged hospital stay (more than 24 hours) when adjusting for age, sex, type of foreign body and mouth sweep as a rescue maneuver.