Pediatrics International

(2003)

45

, 530–533

Original Article

Flexible endoscopy of aerodigestive tract in small infants

YU-SHENG LEE, WEN-JUE SOONG, MEI-JY JENG, CHIN-YUAN CHENG, CHUNG-MIN SHEN, JOHN SUN, CHIUNG-FANG CHEN AND BETAU HWANG

Department of Pediatrics, Taipei Veterans General Hospital; and, National Yang-Ming University School of Medicine, Taipei, Taiwan

Abstract

Background

: Flexible endoscopy (FE) is a useful method for diagnosing airway problems. Congenital oracquired airway lesions in infants may lead to respiratory distress that requires comprehensive investigationand management. This study was designed to evaluate the use of FE in small infants.

Methods

: Infants who had symptoms of respiratory distress and received FE when they were less than1-year-old were studied and their medical history, diagnoses, interventions, and complications from FE wereinvestigated.

Results

: The study population consisted of 568 small infants (334 boys and 234 girls) who weighed5.1

±

2.4 kg, and received FE when they were 4.5

±

3.6 months of age. Most patients (91.2%) receiveddiagnostic FE and the remainder (8.8%) received therapeutic procedures. Stridor (38.0%) was the mostcommon indication for FE and laryngomalacia (33.3%) was the most frequent finding. Synchronous FEdiagnosis was found in 351 (61.8%) cases. No major complications associated with FE were found.

Conclusion

: Flexible endoscopy allows direct visualization of dynamic motion of the small aerodigestivetract. Laryngomalacia was the most common FE finding of respiratory distress in small infants. SynchronousFE lesions were frequently found in this young age group and it necessitated a thorough investigation of theentire aerodigestive tract.

Key words

flexible endoscopy, infants, laryngomalacia, stridor.

Congenital and acquired airway lesions in small infants canlead to symptoms of respiratory distress. This requiresprompt attention including a thorough examination of theiraerodigestive tract. Flexible endoscopy (FE) provides adynamic airway view and has contributed to importantdiagnostic and therapeutic advances in pediatric pulmonol-ogy.

1–3

FE is also a fast, safe, less traumatic and convenientdiagnostic tool that can be performed at the bedside ofpediatric patients.

4

The present study was designed toevaluate the information obtained from FE conducted insmall infants, less than 1-year-old, who had significantrespiratory symptoms.

Methods

We conducted a retrospective analysis of the medical recordsof small infants, less than 1-year-old, who underwent FE atTaipei Veterans General Hospital, Taiwan from January 1996to December 2001. The data included demographic charac-teristics, presenting respiratory symptoms and signs, FEfindings, interventions during FE and associated complica-tions of FE.

An external diameter of 2.2 mm (BFN20, OlympusOptical, Tokyo, Japan) or 3.0 mm (ENT-300PIII, Machida,Tokyo, Japan) FE was used to perform the aerodigestive tractexaminations. All patients were sedated with midazolam andmethohexital sodium intravenously. Topical anesthesia thatconsisted of intranasal and intratracheal instillation of 2%lidocaine solution was used. Continuous oxygen supplementvia a nasopharyngeal catheter was given to keep the oxygensaturation above 90% during the whole examination. Electro-cardiography, respiration and pulse oximetry were continu-ously monitored during, and 4 hours after FE. The entireupper and lower airways, the ear canals, and the esophaguswere carefully examined to obtain diagnostic information.

Correspondence: Wen-Jue Soong MD, Department of Pediatrics,Taipei Veterans General Hospital, No. 201, Sec 2, Shih-Pai Road,Taipei 112, Taiwan. Email: wjsoong@vghtpe.gov.tw

Received 25 September 2002; revised 5 March 2003; accepted24 March 2003.

Flexible endoscopy in infants 531

A written consent was obtained from the parent or guardianfor FE examination.

Results

A total of 568 infants, 334 boys and 234 girls, enrolled in thestudy. Their mean bodyweight at FE was 5.1

±

2.4 kg (mean

±

SD) and ranged from 600 g to 13.0 kg with a medianweight of 4.5 kg. Their mean age at FE was 4.5

±

3.6 months(mean

±

SD) and ranged from 3 days to 12 months with amedian age of 3 months.

The most common indication for FE (Table 1) was stridor(38.0%), followed by respiratory distress (15.3%) andsnoring (9.3%). The FE diagnoses (Table 2) includeanomalies, which were acquired and congenital, in the aerod-igestive tract. Laryngeal site anomalies (44.0%), thatincluded laryngomalacia, larynx granulations, vocal cordparalysis and vocal cord web, were the most frequentfindings in this age group. Laryngomalacia (33.3%), whichrefers to a floppy epiglottis, short aryepiglottic folds,redundant arytenoids/aryepiglottic folds,

5

was the mostcommon diagnosis. The most common esophageal findingwas incompetent gastroesophageal sphincter with erythema-tous mucosa change.

About one-third of cases (217 infants, 38.2%) had onlyone positive finding (Table 3) and the remainder (351 infants,61.8%) had more than one positive finding. Most of thelesions (

n

= 504, 88.7%) were located in the airways(Table 4) and some infants (

n

= 53, 9.3%) had concurrentairway plus esophageal or ear problems. A few (

n

= 11,1.9%) had only esophageal problems. Supraglottis lesionswere found in 198 (34.9%) infants, subglottis lesions werefound in 185 (32.6%) infants, and both supra- and subglottislesions were found in 174 (30.6%) infants (Table 5).

Five hundred and eighteen (91.2%) infants had diagnosticFE only, and 50 (8.8%) infants had additional therapeuticinterventions. Table 6 shows the therapeutic interventions,included FE-aid tracheal intubations, balloon dilatations fortracheobronchial lumen stenosis, stent implantations formalacia sites, foreign body removals and bronchoalveolarlavages. FE was successfully performed in all small infants.Transient desaturation and bradycardia were occasionallyencountered during the FE in some patients who had severecardiopulmonary compromised problems. They recoveredrapidly after the procedure and supplemental oxygen flow.There was no long-term sequela associated with FE examin-ations in the present study.

Discussion

Advances in the development of delicate instrumentation andanesthetic technique have made FE the single most important

Table 1

Indications for flexible endoscopy in 568 respiratorydistress infants

Indications No. cases

Stridor 216Respiratory distress 87Snoring 53Cyanosis 34Persistent lung collapse 33Respiratory failure 27Difficult extubation 26Cardiovascular problems 22Chronic lung disease 16Congenital anomaly 14Frequent choking 13Hoarseness 9Difficult intubation 7Feeding difficulty 6Chronic cough 5

Table 2

Diagnoses

†

on flexible endoscopy in 568 respiratorydistress infants

Diagnosis No. cases

Otitis media/externa 19Upper airway

Laryngomalacia 189Pharyngomalacia 59Mucosa injection/swelling 43Adenoid hypertrophy 37Choanal stenosis/narrowing 21Larynx granulation 20Vocal cord palsy 17Vocal cord web 13Vallecular cyst 11Rhinosinusitis 11Pharynx follicle hypertrophy 7Laryngeal hemangioma 3Choanal atresia 3

Lower airwayBronchomalacia 105Granulations 56Tracheomalacia 53Tracheobronchus 52Tracheal stenosis 50Bronchial stenosis 39Subglottic stenosis 27Carina malaica 7Mucosa injections/swelling 4Foreign body 2

Tracheobronchial inflammation 95Esophagus

Incompetent GE sphincter 38Residual fistula 3Esophagitis 2Varices 1

†

Multiple diagnoses exist.

532 Y-S Lee

et al

.

diagnostic tool in the detection of a dynamic process as wellas in management of the pediatric airways.

6

Stridor was the most common indication for FE in infantsless than 1-year-old in the present study. This was compatiblewith Friedman

et al

.

7

and Hoeve and Rombout

8

who foundstridor or respiratory distress to be the most commonindication for FE in broader pediatric age groups. However,Lindahl

et al

. found that ventilation difficulty was morecommon than stridor as an indication for FE during the firstmonth of life.

9

The present study agrees with Holinger

10

and Lindahl

et al

.

9

who reported that the larynx was the most commonanomaly area and laryngomalacia was the most frequentfinding in this area. Nussbaum and Maggi found that 68% of297 children with laryngomalacia had an associatedrespiratory disorder.

11

It is well established that a significantpercentage of children with laryngeal anomalies may havemultiple coexisting anomalies.

7,12

In our 189 laryngomalaciapatients, 81 (42.9%) had additional FE findings that includedtracheobronchial inflammation (

n

= 29, 35.8%), pharyngo-malacia (

n

= 17, 20.9%), and bronchomalacia (

n

= 12,14.8%). This means that in small infants who haverespiratory symptoms, laryngomalacia may not be the onlyairway problem. We believe that a complete evaluation of the

whole airway is necessary for every symptomatic smallinfant.

Friedman

et al

.

7

and Wood

13

reported that 18.8% of 429children younger than 17 years of age and 15% of 758patients younger than 10 years of age, respectively, had morethan one airway finding on FE. Ungkanont

et al

. reported thatmost (77.4% of 62) symptomatic neonates had multipleairway lesions.

6

In the present study, 61.8% of cases had twoor more synchronous FE findings and 30.6% had both upperand lower airway lesions. We believe that the use of FE willfind more synchronous airway lesions in younger pediatricpatients. A thorough examination of the entire aerodigestivetract is necessary, especially when the patient is under 1 yearof age. If the entire aerodigestive tract is not examined, thensynchronous disorders may not be found in these infants.

Diagnostic FE is a safe and effective method of findingimportant information in the aerodigestive tract. Thisprocedure enables the physician to see abnormalities of theairway structure, size or patency. The real dynamic abnor-malities of the aerodigestive tract, such as malacia, can bestudied with FE because the airway mimics the naturalrespiratory pattern. Radiographic imaging, such as computedtomography scan or magnetic resonance imaging, showsstatic airway conditions and provides limited information.

Therapeutic FE is indicated when there is an airwayobstruction, such as foreign body or mucous plug, which canbe removed with a FE. Although a rigid scope is generallyused to remove foreign bodies, we used FE to removeselected foreign bodies successfully in three infants. Further-more, our team successfully performed FE-aided balloondilatations for tracheobronchial lumen stenosis in ninteensmall infants and stent implantations for airway malacia in

Table 3

Synchronous findings on flexible endoscopy in 568respiratory distress infants

No. positive findings No. cases %

One 217 38.2Airway 206Esophagus 11

Two 226 39.8Airway 195Airway + esophagus 23Airway + ear 8

Three 107 18.8Airway 86Airway + esophagus 10Airway + ear 11

Four 17 3.0Airway 16Airway + ear 1

More than five 1 0.2Airway 1

Table 4

Lesion sites on flexible endoscopy in 568 respiratorydistress infants

Lesion sites No. cases %

Airway only 504 88.7Airway + ear 20 3.5Airway + esophagus 33 5.8Esophagus only 11 1.9

Table 5

Airway lesion sites on flexible endoscopy in 568respiratory distress infants

Lesion site No. cases %

Airway 557 98.1Supraglottis 198 34.9Subglottis 185 32.6Supra- and subglottis 174 30.6

Table 6

Flexible endoscopy in 568 respiratory distress infants

Procedure No. cases %

Diagnostic 518 91.2Therapeutic 50 8.8

Balloon dilatation 19 3.3Tracheal intubation 14 2.5Stent implantation 8 1.4Bronchoalveolar lavage 6 1.1Foreign body removal 3 0.5

Flexible endoscopy in infants 533

eight small infants. All of these procedures were performedsmoothly without any significant complication.

While transient desaturation and bradycardia occurred,especially when the FE passed into the trachea, infantsrecovered quickly after temporary removal of the FE andoxygen supplementation. No long-term sequela or complica-tion were associated with the procedure. Although the FE isrelatively safe and convenient, continuous cardiopulmonarymonitoring, appropriate oxygen supplement and skilled andexperienced personnel are still required.

14

Conclusion

Flexible endoscopy is essential for evaluating small infantswho may have airway problems. FE is a safe procedure thatprovides both diagnostic and therapeutic interventions withminimal complications. Laryngeal lesions, especially laryn-gomalacia, were the most frequent abnormality observed insmall infants. Synchronous FE findings were found morefrequently in young children. Therefore, we recommend acomplete FE of the entire aerodigestive tract, including theupper and lower airway, esophagus and ear canals in everysymptomatic small infant.

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