ELECTRONIC SUBMISSION FOR CONSIDERATION IN
UNIVERSITY OF TORONTO MEDICAL JOURNAL (UTMJ)
Review Article
Airway Foreign Bodies (AFBs)
Ala’addin M M Salih
MBBS Candidate Class 2013, Faculty of Medicine, University of Khartoum,
Khartoum, Sudan.
Intern medical student, Paediatrics Emergency Centre-Hamad General
Hospital, Hamad Medical Corporation, Doha, Qatar.
Correspondence
Email: alaaddinsalih@yahoo.com
1
Airway Foreign Bodies (AFBs)
Abstract:
Airway foreign bodies (AFBs) are common area for study of emergency medicine,
otolaryngology, and paediatrics. It is an important medical issue for its direct relation to the
most important vital process, respiration. Instead, it is poorly covered in the literature.
Sudden impaction of an element in the airways is a widespread clinical scenario among
children under-two children. Cases are classified based on: classical features, degree of
airway obstruction, and source of the foreign body. The main etiology is food or fluid
misdirection. Pathophysiology is determined by the nature of the aspirated body. Classical
presentation is a triade of coughing, chocking, and sneezing. On admission, the chief
presenting complaint is shortness of breathing (SOB). Differential diagnosis consists of
obstructing diseases of the upper respiratory tract. Diagnosis is a three-step protocol but
witnessed aspiration is diagnostic. History shows sudden onset of the characteristic
symptoms. Physical examination reveals signs of respiratory distress as hypoxia,
hypercapnia, cyanosis, and abnormal breathing sounds (e.g. wheezing, sonorous rhonchi, and
expiratory stridor). Chest X-ray imaging is the specific investigation of choice. Management
is by emergency bronchoscopy. Pulmonary and cardiac complications are significantly
reduced with early intervention. Family education is the hallmark of prevention.
Keywords: Airway foreign bodies; Café Coronary Syndrome; respiratory tract; airway
obstruction; breathing difficulties.
Definition:
An airway foreign body (AFB) is an exogenous or endogenous object that is abnormally
present in the respiratory passages. Also it is known as "Café Coronary Syndrome", a
2
description coined by Hangen in 19631. Common sites of bodies' impaction are the right main
bronchus and lobar bronchioles2. Other possible sites are summarized in table 1.
Table 1: Sites of airway obstruction and the associated complications.
Site of obstruction
Mouth or nasal cavity
Expected lung complication
Maintained respiration due to alternative breathing by the
other route.
Pharynx Naso-pharynx
Maintained respiration due to passage of air by the
unobstructed oro-pharynx.
Oro-pharynx
Mild, moderate, or severe reduction in lung volume (LV)
depending on the size and shape of the body.
Laryngo-pharynx
Complete bilateral lung collapse.
Trachea
Complete bilateral lung collapse.
Main bronchi3
Partial or complete unilateral lung collapse.
Lobular bronchioles
Partial or complete lobular collapse.
Terminal bronchioles
Partial or complete alveolar collapse.
Classification:
AFBs are classified based on three major criteria: classical assessment, degree of airway
obstruction, and source of the body. Firstly in classical classification4, some points are
considered as: patient age, nature of foreign body, and site where the body lodged. Secondly,
according to degree of the Foreign Body Airway Obstruction (FBAO) there are two types,
1
Fleischer K Erkennung, Entfernung Von. Bronchial-fremdkorpern-einst Jetzt. Ther Ggegenw 1974; 113: 34858.
2
Helen Williams. Inhaled foreign bodies. ADC Edu Pract Ed 2005; 90 (2): 31-3.
3
Wick R, Gilbert JD, & Byard RW. Café Coronary Syndrome ‘fatal choking on food’: an autopsy approach. J
Clin Forensic Med 2006 Apr; 13 (3): 135-8.
4
CLN Robinson, William W Mushin. Inhaled foreign bodies. Br Med J 1956 Aug 11; 2: 324-8.
3
partial and complete obstruction. Thirdly, sources of AFBs are either endogenous (e.g.
mucoceles, bronchial casts … etc.) or exogenous (e.g. medications, solids, and food
particles). For the endogenous bodies, mucocoeles and bronchial casts are common causes5.
While for the exogenous ones, pills and capsules are the only aspirated drugs. Commonly
impacted solid particles are small toys and plastic bags. Inhalation of food elements is the
predominant, peanuts only constitutes about 40% of all cases6. Relationship between type of
the aspirated food and the geographical area has been reported. Inhalation of peanuts,
watermelon seeds, sunflower seeds, and pumpkin seeds is more prevalent in USA and
Europe, Egypt, Turkey, and Greece, respectively.7
Figure 1 shows this classification.
Classification of Airway Foreign Bodies
Classical classification
Patient
age
Foreign
body type
Foreign
body
location
According to degree
Foreign Body Airway
Obstruction (FBAO)
Partial
obstruction
According to foreign
body original source
Complete
obstruction
Endobodies
Exobodies
Figure 1: Classification of airway foreign bodies.
5
HA El-Munshid. Gastrointestinal Physiology. In: MY Sukkar, HA El-Munshid, MSM Ardawi. Concise
Human Physiology. 2nd Ed. Oxford: Blackwell; 2000, P. 159.
6
JY Park, AA Elshami, DS Kang, TH Jung. Plastic Bronchitis. Eur Respir J 1996; 9: 612-14.
7
D Vijayasekaran, A P Sambandam, N C Gowrishankar. Acute Plastic Bronchitis. Indian Paediatr 2004 Dec
17; 41: 1257-9.
4
Epidemiology:
An American study estimates mortality rate due to Foreign Body Airway Obstruction
(FBAO) as 0.66 per 100,0008. A British study found age-adjusted period prevalence of AFBs
during childhood to be:
Table 2: Age-adjusted period prevalence of AFBs among British children.9
> 0-1 yr.
> 1-2 yrs.
> 2-3 yrs.
> 3-4 yrs.
> 4-5 yrs.
> 5-6 yrs.
> 6 yrs.
Sex
Male
Age
7.4 %
28.1 %
13 %
1.5 %
1.5 %
1.6 %
9.3 %
Female
8.1 %
25.2 %
6.7 %
1.5 %
0.7 %
0.8 %
4.8 %
In Australia, the incidence of asphyxia secondary to FBAO was 15.1 per 100,000.10
Male to female patients' ratio is 2:1 for unknown reasons11. The peak was between six
months and three years. In adults, AFBs occur only by accident12. A significant increase was
reported among elderly during their sixth decade of life13. Higher incidence was detected
among certain groups: mental retarded, psychotic patients, and those with previous suicidal
attempts14.
Etiology:
8
Hughes CA, Baroody FM, Marsh BR. Pediatric tracheobronchial foreign bodies: historical review from the
Johns Hopkins Hospital. Ann Otol Rhinol Laryngol 1996 Jul; 105 (7):555-61.
9
Mucoid impaction [homepage on the Internet]. Buckinghamshire: General Electric Company; 2010. Available
from: http://www. medcyclopaedia.com/.
10
Cotton RT, Myer CM, Shott SR. The pediatric airway: An interdisciplinary approach. Philadelphia: JB
Lippincott Company; 1995.
11
Rimell FL, Thome A Jr, Stool S, et al. Characteristics of objects that cause choking in children. JAMA 1998
Dec 13; 274 (22): 1763-6.
12
Henry KK Tan, Karla Brown, Trevor McGill, Margaret A Kenna. Airway foreign bodies (FB): a 10-year
review. Int J Pediatr Otorhinolaryngol 2000; 56: 91–9.
13
Rothmann BF, Boeckman CR. Foreign bodies in the larynx and tracheobronchial tree in children: A review of
225 cases. Ann Otol Rhinol Laryngol Sep-Oct 1980; 89 (5 Pt 1): 434-6.
14
Farhad Baharloo, Francis Veyckemans, Charles Francis, Marie-Paule Biettlot, Daniel O. Rodenstein.
Tracheobronchial Foreign Bodies: Presentation and Management in Children and Adults. Chest 1999 May; 115
(5): 1357-62.
5
Causes are of great variety. Most cases follow engulfment of entities in persons who have not
developed the necessary masticatory (chewing) skills. Another cause is physical activities
during eating which disrupt concentration and increase respiratory rate and depth driving the
food into larynx rather than oesophagus. Idiopathic AFBs occurs spontaneously due to food
or fluid misdirection during the second stage of swallowing (deglutination), the pharyngeal
stage15. Finally, AFBs may originate from endogenous sources as mucoid impaction and
bronchial casts.
Pathophysiology:
The nature of the foreign body determines pathogenesis. Metallic bodies cause mild
inflammation. Fatty materials stimulate intense chemoinflammatory reactions against fatty
acid contents16. Starchy food adsorbs fluids, increasing particles size and subsequently
obstruction severity17.
Airway obstruction by an endogenous body is commonly associated with respiratory tract
infections that increase both mucus production and secretion. Plastic bronchitis (also known
as fibrinous/pseudomembranous/Hoffman's/and cast bronchitis18) is commonly seen in
chronic asthmatics, adults with cardiac and pericardial diseases, and children with congenital
heart diseases. It is characterized by bronchial casts formation by unknown mechanism.19,20
Clinical Features:
1) Symptoms:
15
Tarig Hakim Merghani. The Core of Medical Physiology. 1 st Ed. Khartoum: Khartoum University Printing
Press; 2008.
16
William F Ganong. Review of Medical Physiology. 22 th Ed. London: McGraw-Hill; 2005, P. 678.
17
Inhaled Foregin Body [homepage on the Internet]. Florida: DSHI Systems Inc.; 27 Apr 2009. Available from:
http://www.freemd.com/.
18
LJ Hoeve, J Rombout, DJ Pot. Foreign body aspiration in children: The diagnostic value of signs, symptoms
and pre-operative examination. Clin Otolaryngo & Allie Scien Feb 1993; 18 (1): 55-7.
19
I Alfageme, N Reyes, M Merino. Aspirated foreign body. Int J Pulmon Med 2007; 7 (1): 5-6.
20
Webb WA. Management of foreign bodies of the upper gastrointestinal tract. Gastrointest Endosc 1995 Jan;
41 (1): 39-51.
6
Typical classical presentation is sudden onset of coughing, sneezing, and chocking. The
former two are considered as protective reflex against impaction of the foreign body.
Coughing mechanism is initiated by a deep inspiration followed by a forced expiration
against a closed glottis, this would markedly increase the intrapleural pressure resulting in an
explosive air outflow. During sneezing the same occurs except for glottis that is kept
opened21. Choking is simply due to a mechanical obstruction that precedes breathing
difficulties and it may be accompanied by horsy voice or dysphonia22.
2) Signs:
Clinical findings include: decreased respiratory rate and depth, raspy respiration23, dyspnoea,
hypoxia, hypercapnia, and cyanosis. Associated signs of breathing difficulties may also
present e.g. noisy breathing, nasal flaring, and use of accessory respiratory muscles.
Generally patients are anxious and have ptyalism24,25.
On auscultation, examining doctor may hear wheezing, sonorous rhonchi, or expiratory
stridor. Bilateral wheezing indicates partial upper respiratory tract obstruction, while
unilateral one is an ominous sign associated with occluded lower passages. Sonorous
rhonchus is a special high pitch wheezing sound characterizing aspiration of a large foreign
body26. Atypical expiratory stridor auscultated over lung landmarks is a sign of lower airway
obstruction27.
21
Paulo FS, Bittencourt Paulo, AM Camargos. Foreign body aspiration. J Pediatr (Rio J) 2002; 78 (1): 9-18.
Robert A Harris. Carbohydrate Metabolism: Major Metabolic Pathways and their Control. In: Thomas M
Devlin, Textbook of Biochemistry with Clinical Correlations. 50 th Ed: New York; Wiley-Liss, 2002, P. 651.
23
Singh B, Kantu M, Har-El G, Lucente FE. Complications associated with 327 foregin bodies of the pharynx,
larynx, & esophagus. Ann Otol Rhinol Laryngol 1997;106: 301-4.
24
Foregin Body Aspiration [homepage on the Internet]. Minnesota: Family practice notebook, LLC.; 22 Mar
2010. Available from: http://www.fpnotebook.com/.
25
Review of Inhaled Foregin Body [homepage on the Internet]. Amsterdam: Elsevier Inc.; 24 Aug 2007.
Available from: http://www.mdconsult.com/.
26
Sapira JD, Orient JM. Sapira's art and science of bedside diagnosis. Hagerstwon: Lippincott Williams &
Wilkins; 2000.
27
Joseph T Zerellaab, Michael Dimlerab, Leigh C McGillab, Kenneth J Pippus. Foreign body aspiration in
children: Value of radiography and complications of bronchoscopy. J Pediatr Surg 1998 Nov; 33(11): 1651-4.
22
7
Differential Diagnoses:
Missed AFB is the first differential. A list of diseases that have similar symptoms and signs
of AFBs should be considered. These diseases could be divided based on the site of
obstruction into:28 laryngeal obstructing diseases (e.g. epiglottitis, subglottic laryngitis, and
laryngeomalacia29), tracheal obstructing diseases (e.g. croup, tracheal lesions, strictures,
stenosis, and tracheomalacia), bronchial obstructing diseases (e.g. Congenital Cystic
Adenomatoid Malformation (CCAM), bronchial compression, and plastic bronchitis), lobar
obstructing diseases (e.g. asthma and lobar atelectasis), and bronchial obstructing diseases.
(e.g. bronchiolitis, bronchiectasis, bronchiolitis obliterans, and Bronchiolitis Obliterans with
Organizing Pneumonia (BOOP)).
Diagnosis:
Definitive diagnosis could be reached following this three-step protocol. Step one is
obtaining of a detailed history stressing on two points, sudden onset of the symptoms and
witnessed aspiration process. Presence of a witness for the inhalation is diagnostic. Next step
is to detect the vital signs and conduct a general physical examination with a special attention
to positive signs in E.N.T., respiratory mucosa, mouth, and lips. Last step is diagnosis
confirmation with some investigations.
These investigations are radiological imaging and laboratory tests. Ordering in a priority
declining manner, chest X-rays (CXRs) are the most important. It would show either the body
itself, or signs of ipsilateral lung hyperinflation or collapse in case of partial or complete
airway obstruction, respectively.
28
Robert C Brasch. Airway Obstruction in Children: From Croup to BOOP [monograph on the Internet]. Berlin:
Siemens and Bayer Schering Pharma; unknown date. Available from: http://www.starprogram.com/resource.ashx/abstract/973.
29
Ginsberg GG. Management of ingested foreign objects & food bolus impactions. Gastrointest Endosc, 1995;
41:33-8.
8
CXR films are two, inspiratory-expiratory and lateral decubitus. The former is more
informative as it shows lung boundaries clearly particularly in kids. Inspiratory-expiratory
films could be taken in posteroanterior (PA) or anteroposterior (AP) views. For the two views
films taken during expiration would give more information.30
Experienced X-ray film reading is the key point. Partial or complete upper respiratory tract
obstruction appears as bilateral lung hyperinflation or collapse, respectively. While partial or
complete lower airway occlusion results in reduction or total collapse of the ipsilateral lung
and compensatory hyperinflation of the contralateral one.
Direct bronchoscopy to visualize and remove trapped foreign bodies in anatomical dead
space of the respiratory tract could be done. Early bronchoscopic intervention gives better
outcome31. Less specific tests are computerized topography (CT) scan and Iodine and Barium
fluoroscopy32.
Scanning investigations to estimate patient's general condition are: pulse oximetry, arterial
blood gases saturation, serum electrolytes, and complete blood count (CBC).
Management:
Prevention is the cornerstone of management. Parents education should inform them with the
golden rules of caring about their children and importance of keeping close supervision,
methods of choosing suitable age-designed toys, use alternatives of small and easily inhaled
objects, and proper first aid to help AFBs patients.
In case of witnessed foreign body aspiration or sudden onset of AFB symptoms, parents
should rapidly rush the patient to the hospital or ask for ambulance help. During this they
should conduct the Basic Life Support (BLS) skills followed by the necessary first aids.
30
DM Griffiths, NV Freeman. Expiratory Chest X-Ray Examination In The Diagnosis of Inhaled Foreign
Bodies. Br Med J 1984 Apr; 288: 1074-5.
31
Foreign body aspiration-Diagnosis-Best Practice [homepage on the Internet]. London: BMJ Publishing group;
2010. Available from: http://www.bestpractice.bmj.com/.
32
Swanson KL. Airway foreign bodies: what’s new?. Semin Resp Crit Care Med 2004 Aug 25; 4: 405-11.
9
Enhancing active coughing is the best defensive mechanism. Next lifesaver is Heimlich
manoeuvre in case of complete obstruction. Artificial respiration techniques like mouth-tomouth breathing or cardio-pulmonary resuscitation (CPR) are absolutely contraindicated
because they may worsen the condition by impacting the body due to high atmospheric
pressure gradient. Instead, it could be applied cautiously if the trapped body was ultimately
severe33.
In emergency room (ER), priority is for life saving by Advanced Life Support (ALS) steps.
Laryngeal oxygen mask (LOM) is critical for resuscitation. Restricted mechanical ventilation
used for life-threating cases or in absence of a bronchoscopy-trained otolaryngologist.
On admission, emergency bronchoscopy under general anaesthesia is the first line of
treatment. First bronchoscopy for removal of an AFB was done by Gustav Killiar in 189734.
Rigid bronchoscopy is superior to flexible fiberoptic bronchoscopy for its high degree of
body controllability35. Tracheotomy or tracheostomy is the least approach indicated in failed
bronchoscopy, unusual airway foreign bodies, and in tandem with laryngoscopy for
management of late laryngeal obstruction36,37. Surgical procedures for AFBs extraction are
safe. Pre- or postoperative prescription may contain steroids and broad-spectrum antibiotics
for prophylaxis or treatment38. During convalescence family members should observe the
patient closely.
Complications:
33
Arthur C Guyton, John E Hall. Textbook of Medical Physiology. 11 th Ed. Pennsylvania: Elsevier Inc.; 2006,
P. 155.
34
Mittleman RE, Wetli CV. The fatal cafe coronary; Foreign-body airway obstruction. JAMA 1982 Mar 5; 247
(9): 1285-8.
35
Sami El-Yas, Mohammed E. Ahmed. Surgical removal of perfume stopper impacted in the pharynx, KMJ
2008 May;1 (2): 93-4.
36
Andrew H Limper, Udaya B Prakash. Tracheobronchial Foreign Bodies in Adults. Ann Intern Med 1990 Apr
15; 112 (8): 604-9.
37
Foregin bodies, trachea [homepage on the Internet]. Virginia: Medscape; 8 Sep 2009. Available from:
http://www.emedicine.medscape.com/.
38
O A Abdulmajid, A M Ebeid, M M Motaweh, I S Kleibo. Aspirated foreign bodies in the tracheobronchial
tree: report of 250 cases. Thorax 1976; 31(6): 635-40.
10
Early diagnosis and adequate management are essential to avoid pulmonary and cardiac
complications. Lung complications depend on the nature of the foreign body e.g. sharp AFBs
cause lung perforation while blunt ones lacerate it. Immediate complications are breathing
difficulties, reduced respiratory rate and depth, hypoxia, hypercapnia, and cyanosis.
Pneumonia and secondary bacterial infections are other complications that present as pyrexia,
cough, and purulent sputum39. Longstanding pneumonia with inflammatory exudate may
complicated by bronchiectasis, lung abscesses, and interstitial fibrosis. Emphysema, tracheaoesophageal fistula, and ultimately radical lungectomy are the most serious consequences.
Another inflammation is bronchial granuloma that is unique for aspiration of vegetable
particles and characterized microscopically by presence of foreign body giant cells40,41. Few
hours later patients may develop systemic manifestations as bacteraemia, septicaemia, and
septic shock.
Conclusion:
AFBs are a merit medical issue. Its clinical importance is of evolving nature particularly with
current explosion in global population and birth rate in certain regions of the world like
Africa, Middle East, and Latin America42. Foreign body may be endo- or exogenous. Clinical
picture has broad spectrum of sudden onset of breathing abnormalities in respiratory rate and
depth, ranging from partial to complete airway obstruction, depending on the size and site
where the body lodged.
What is really important for parents is to target the primordial prevention. Doctors ought to
keep in mind AFBs as a differential diagnosis and be well-trained on dealing with such cases.
39
Vinary Kumar, Abul K Abbas, Nelson Fausto, Richard N Mitchell. Robbins Basic Pathology. 8 th Ed.
Philadelphia: Sunders Elsevier; 2007.
40
Juerg Barbena, Robert G. Berkowitzb, Andrew Kempc, John Massie. Bronchial granuloma: where's the foreign
body?. Int J Pediatr Otorhinolaryngo 2000 Jul 14; 53 (3): 215-9.
41
RNM MacSween, K Whaley. Muir’s Textbook of Pathology. 13 th Ed. London: Arnold; 1992.
42
List of sovereign states and dependent territories by birth rate [homepage on the Internet]. Los Angeles:
Wikipedia; 19 Dec 2010. Available from: http://en.wikipedia.org/.
11
Acknowledgements:
The author thanks Dr. Khalid M. A\Allah (Paediatrics consultant) for his endless editorial
contributions. Also he would like to thank Dr. Mohammed B. Al-Nayer (Paediatrics senior
specialist) for his guidance and support. Their continuous enthusiasm and encouragement is
highly appreciated.
12
References
1. Fleischer K Erkennung, Entfernung Von. Bronchial-fremdkorpern-einst Jetzt. Ther
Ggegenw 1974; 113: 348-58.
2. Helen Williams. Inhaled foreign bodies. ADC Edu Pract Ed 2005; 90 (2): 31-3.
3. Wick R, Gilbert JD, Byard RW. Café Coronary Syndrome ‘fatal choking on food’: an
autopsy approach. J Clin Forensic Med 2006 Apr; 13 (3): 135-8.
4. CLN Robinson, William W Mushin. Inhaled foreign bodies. Br Med J 1956 Aug 11;
2: 324-8.
5. HA El-Munshid. Gastrointestinal Physiology. In: MY Sukkar, HA El-Munshid, MSM
Ardawi. Concise Human Physiology. 2nd Ed. Oxford: Blackwell; 2000, P. 159.
6. JY Park, AA Elshami, DS Kang, TH Jung. Plastic Bronchitis. Eur Respir J 1996; 9:
612-14.
7. D Vijayasekaran, A P Sambandam, N C Gowrishankar. Acute Plastic Bronchitis.
Indian Paediatr 2004 Dec 17; 41: 1257-9.
8. Hughes CA, Baroody FM, & Marsh BR. Pediatric tracheobronchial foreign bodies:
historical review from the Johns Hopkins Hospital. Ann Otol Rhinol Laryngol 1996
Jul; 105 (7):555-61.
9. Mucoid impaction [homepage on the Internet]. Buckinghamshire: General Electric
Company; 2010. Available from: http://www. medcyclopaedia.com/.
10. Cotton RT, Myer CM, Shott SR. The pediatric airway: An interdisciplinary approach.
Philadelphia: JB Lippincott Company; 1995.
11. Rimell FL, Thome A Jr, Stool S, et al. Characteristics of objects that cause choking in
children. JAMA 1998 Dec 13; 274 (22): 1763-6.
12. Henry KK Tan, Karla Brown, Trevor McGill, Margaret A Kenna. Airway foreign
bodies (FB): a 10-year review. Int J Pediatr Otorhinolaryngol 2000; 56: 91–9.
13
13. Rothmann BF, Boeckman CR. Foreign bodies in the larynx and tracheobronchial tree
in children: A review of 225 cases. Ann Otol Rhinol Laryngol Sep-Oct 1980; 89 (5 Pt
1): 434-6.
14. Farhad Baharloo, Francis Veyckemans, Charles Francis, Marie-Paule Biettlot, Daniel
O. Rodenstein. Tracheobronchial Foreign Bodies: Presentation and Management in
Children and Adults. Chest 1999 May; 115 (5): 1357-62.
15. Tarig Hakim Merghani. The Core of Medical Physiology. 1st Ed. Khartoum:
Khartoum University Printing Press; 2008.
16. William F Ganong. Review of Medical Physiology. 22th Ed. London: McGraw-Hill;
2005, P. 678.
17. Inhaled Foregin Body [homepage on the Internet]. Florida: DSHI Systems Inc.; 27
Apr 2009. Available from: http://www.freemd.com/.
18. LJ Hoeve, J Rombout, DJ Pot. Foreign body aspiration in children: The diagnostic
value of signs, symptoms and pre-operative examination. Clin Otolaryngo & Allie
Scien Feb 1993; 18 (1): 55-7.
19. I Alfageme, N Reyes, M Merino. Aspirated foreign body. Int J Pulmon Med 2007; 7
(1): 5-6.
20. Webb WA. Management of foreign bodies of the upper gastrointestinal tract.
Gastrointest Endosc 1995 Jan; 41 (1): 39-51.
21. Paulo FS, Bittencourt Paulo, AM Camargos. Foreign body aspiration. J Pediatr (Rio
J) 2002; 78 (1): 9-18.
22. Robert A Harris. Carbohydrate Metabolism: Major Metabolic Pathways and their
Control. In: Thomas M Devlin, Textbook of Biochemistry with Clinical Correlations.
50th Ed: New York; Wiley-Liss, 2002, P. 651.
14
23. Singh B, Kantu M, Har-El G, Lucente FE. Complications associated with 327 foregin
bodies of the pharynx, larynx, & esophagus. Ann Otol Rhinol Laryngol 1997;106:
301-4.
24. Foregin Body Aspiration [homepage on the Internet]. Minnesota: Family practice
notebook, LLC.; 22 Mar 2010. Available from: http://www.fpnotebook.com/.
25. Review of Inhaled Foregin Body [homepage on the Internet]. Amsterdam: Elsevier
Inc.; 24 Aug 2007. Available from: http://www.mdconsult.com/.
26. Sapira JD, Orient JM. Sapira's art and science of bedside diagnosis. Hagerstwon:
Lippincott Williams & Wilkins; 2000.
27. Joseph T Zerellaab, Michael Dimlerab, Leigh C McGillab, Kenneth J Pippus. Foreign
body aspiration in children: Value of radiography and complications of bronchoscopy.
J Pediatr Surg 1998 Nov; 33(11): 1651-4.
28. Robert C Brasch. Airway Obstruction in Children: From Croup to BOOP [monograph
on the Internet]. Berlin: Siemens and Bayer Schering Pharma; unknown date.
Available from: http://www.star-program.com/resource.ashx/abstract/973.
29. Ginsberg GG. Management of ingested foreign objects & food bolus impactions.
Gastrointest Endosc, 1995; 41:33-8.
30. DM Griffiths, NV Freeman. Expiratory Chest X-Ray Examination In The Diagnosis
of Inhaled Foreign Bodies. Br Med J 1984 Apr; 288: 1074-5.
31. Foreign body aspiration-Diagnosis-Best Practice [homepage on the Internet]. London:
BMJ Publishing group; 2010. Available from: http://www.bestpractice.bmj.com/.
32. Swanson KL. Airway foreign bodies: what’s new?. Semin Resp Crit Care Med 2004
Aug 25; 4: 405-11.
33. Arthur C Guyton, John E Hall. Textbook of Medical Physiology. 11th Ed.
Pennsylvania: Elsevier Inc.; 2006, P. 155.
15
34. Mittleman RE, Wetli CV. The fatal cafe coronary; Foreign-body airway obstruction.
JAMA 1982 Mar 5; 247 (9): 1285-8.
35. Sami El-Yas, Mohammed E. Ahmed. Surgical removal of perfume stopper impacted
in the pharynx, KMJ 2008 May;1 (2): 93-4.
36. Andrew H Limper, Udaya B Prakash. Tracheobronchial Foreign Bodies in Adults.
Ann Intern Med 1990 Apr 15; 112 (8): 604-9.
37. Foregin bodies, trachea [homepage on the Internet]. Virginia: Medscape; 8 Sep 2009.
Available from: http://www.emedicine.medscape.com/.
38. O A Abdulmajid, A M Ebeid, M M Motaweh, I S Kleibo. Aspirated foreign bodies in
the tracheobronchial tree: report of 250 cases. Thorax 1976; 31(6): 635-40.
39. Vinary Kumar, Abul K Abbas, Nelson Fausto, Richard N Mitchell. Robbins Basic
Pathology. 8th Ed. Philadelphia: Sunders Elsevier; 2007.
40. Juerg Barbena, Robert G. Berkowitzb, Andrew Kempc, John Massie. Bronchial
granuloma: where's the foreign body?. Int J Pediatr Otorhinolaryngo 2000 Jul 14; 53
(3): 215-9.
41. RNM MacSween. K Whaley. Muir’s Textbook of Pathology. 13th Ed. London:
Arnold; 1992.
42. List of sovereign states and dependent territories by birth rate [homepage on the
Internet].
Los
Angeles:
Wikipedia;
http://en.wikipedia.org/.
16
19
Dec
2010.
Available
from: