Laryngoscopy

Laryngoscopy (/ˌlærɪŋˈɡɒskəpi/) is endoscopy of the

Laryngoscopy
larynx, a part of the throat. It is a medical procedure that is
used to obtain a view, for example, of the vocal folds and
the glottis. Laryngoscopy may be performed to facilitate
tracheal intubation during general anaesthesia or
cardiopulmonary resuscitation or for surgical procedures
on the larynx or other parts of the upper tracheobronchial
tree.

Direct laryngoscopy
View of the glottis as seen during
Direct laryngoscopy is carried out (usually) with the laryngoscopy
patient lying on his or her back; the laryngoscope is
inserted into the mouth on the right side and flipped to the ICD-9-CM 31.42 (http://icd9cm.chrisen
left to trap and move the tongue out of the line of sight, dres.com/index.php?srchtyp
and, depending on the type of blade used, inserted either e=procs&srchtext=31.42&Su
anterior or posterior to the epiglottis and then lifted with an bmit=Search&action=search)
upwards and forward motion ("away from you and MeSH D007828
towards the roof "). This move makes a view of the glottis
possible. This procedure is done in an operation theatre OPS- 1-610 (http://www.icd-code.d
with full preparation for resuscitative measures to deal 301 code e/ops/code/1-610.html)
with respiratory distress. There are at least ten different MedlinePlus 007507
types of laryngoscope used for this procedure, each of
which has a specialized use for the otolaryngologist and medical
speech pathologist. This procedure is most often employed by
anaesthetists for endotracheal intubation under general anaesthesia,
but also in direct diagnostic laryngoscopy with biopsy. It is
extremely uncomfortable and is not typically performed on
conscious patients, or on patients with an intact gag reflex.

Indirect laryngoscopy
Indirect laryngoscopy is performed whenever the provider
visualizes the patient's vocal cords by a means other than obtaining Anatomical parts seen during
a direct line of sight (e.g. a mirror). For the purpose of intubation, laryngoscopy
this is facilitated by fiberoptic bronchoscopes, video laryngoscopes,
fiberoptic stylets and mirror or prism optically enhanced
laryngoscopes.

History
Some historians (for example, Morell Mackenzie) credit Benjamin Guy Babington (1794–1866), who
called his device the "glottiscope", with the invention of the laryngoscope.[1] Philipp von Bozzini (1773–
1809)[2][3] and Garignard de la Tour were other early physicians to use mouth mirrors to inspect the
oropharynx and hypopharynx.[4]

In 1854, the vocal pedagogist Manuel García (1805–1906) became

the first man to view the functioning glottis and larynx in a living
human. García developed a tool that used two mirrors for which the
Sun served as an external light source.[5][6] Using this device, he
was able to observe the function of his own glottic apparatus and
the uppermost portion of his trachea. He presented his findings at
the Royal Society of London in 1855.[7][8]
The laryngoscopy. From García,
All previous observations of the glottis and larynx had been 1884
performed under indirect vision (using mirrors) until 23 April 1895,
when Alfred Kirstein (1863–1922) of Germany first described
direct visualization of the vocal cords. Kirstein performed the first direct laryngoscopy in Berlin, using an
esophagoscope he had modified for this purpose; he called this device an autoscope.[9] It is believed that
the death in 1888 of Emperor Frederick III[10] motivated Kirstein to develop the autoscope.[11]

In 1913, Chevalier Jackson was the first to report a high rate of success for the use of direct laryngoscopy
as a means to intubate the trachea.[12] Jackson introduced a new laryngoscope blade that had a light source
at the distal tip, rather than the proximal light source used by Kirstein.[13] This new blade incorporated a
component that the operator could slide out to allow room for passage of an endoracheal tube or
bronchoscope.[14]

That same year, Henry Harrington Janeway (1873–1921) published results he had achieved using another
new laryngoscope he had recently developed.[15] An American anesthesiologist practicing at Bellevue
Hospital in New York City, Janeway believed that direct intratracheal insufflation of volatile anesthetics
would provide improved conditions for surgery of the nose, mouth and throat. With this in mind, he
developed a laryngoscope designed for the sole purpose of tracheal intubation. Similar to Jackson's device,
Janeway's instrument incorporated a distal light source. Unique however was the inclusion of batteries
within the handle, a central notch in the blade for maintaining the tracheal tube in the midline of the
oropharynx during intubation, and a slight curve to the distal tip of the blade to help guide the tube through
the glottis. The success of this design led to its subsequent use in other types of surgery. Janeway was thus
instrumental in popularizing the widespread use of direct laryngoscopy and tracheal intubation in the
practice of anesthesiology.[11]

Applications
Helps in intubation during the administration of general anaesthesia or for mechanical
ventilation.
Detects causes of voice problems, such as breathing voice, hoarse voice, weak voice, or no
voice.
Detects causes of throat and ear pain.
Evaluates difficulty in swallowing : a persistent sensation of lump in the throat, or mucous
with blood.
Detects strictures or injury to the throat, or obstructive masses in the airway.

Conventional laryngoscope
The vast majority of tracheal intubations involve the use of a
viewing instrument of one type or another. Since its introduction by
Kirstein in 1895,[9] the conventional laryngoscope has been the
most popular device used for this purpose. Today, the conventional
laryngoscope consists of a handle containing batteries with a light
source, and a set of interchangeable blades.

Laryngoscope blades

Early laryngoscopes used a straight "Magill Blade", and this design

is still the standard pattern veterinary laryngoscopes are based Laryngoscope handles with an
upon; however the blade is difficult to control in adult humans and assortment of Miller blades (large
can cause pressure on the vagus nerve, which can cause adult, small adult, pediatric, infant,
unexpected cardiac arrhythmias to spontaneously occur in adults. and neonate)

Two basic styles of laryngoscope blade are currently commercially

available: the curved blade and the straight blade. The Macintosh
blade is the most widely used of the curved laryngoscope
blades,[16] while the Miller blade[17] is the most popular style of
straight blade.[18] Both Miller and Macintosh laryngoscope blades
are available in sizes 0 (neonatal) through 4 (large adult). There are
many other styles of curved and straight blades (e.g., Phillips,
Robertshaw, Sykes, Wisconsin, Wis-Hipple, etc.) with accessories
such as mirrors for enlarging the field of view and even ports for
the administration of oxygen. These specialty blades are primarily
designed for use by anesthetists, most commonly in the operating
room.[19] Additionally, paramedics are trained to use direct
laryngoscopy to assist with intubation in the field.

The Macintosh blade is positioned in the vallecula, anterior to the

epiglottis, lifting it out of the visual pathway, while the Miller blade
is positioned posterior to the epiglottis, trapping it while exposing
Laryngoscope handle with an
the glottis and vocal folds. Incorrect usage can cause trauma to the
assortment of Macintosh blades
front incisors; the correct technique is to displace the chin upwards
(large adult, small adult, pediatric,
and forward at the same time, not to use the blade as a lever with
infant, and neonate)
the teeth serving as the fulcrum.

The Miller, Wisconsin, Wis-Hipple, and Robertshaw blades are

commonly used for infants. It is easier to visualize the glottis using
these blades than the Macintosh blade in infants, due to the larger
size of the epiglottis relative to that of the glottis.

Vie Scope Direct Line of Site

Laryngoscope by Adroit Surgical
 Year
Blade Named for Comments
introduced

Straight tongue with distal

[20] 7 cm. tubular, designed
Bainton Cedric Bainton 1987
specifically for pathologic
conditions

Cranwall George D. Cranton and Barry L. Wall 1963 straight, no flange

Jackson Chevalier Jackson straight

Janeway Henry H. Janeway straight

Reduced Flange curved reduced flange at

George D. Cranton 1999
(RF Mac) heel

Macintosh[21] Robert Macintosh 1943 curved

Magill[22] Ivan Magill 1921 straight

Lever-tip for anterior

displacement of the
McCoy[23] 1993 Epiglottic vallecula and
epiglottis in difficult
intubation.

Miller Robert A. Miller 1941 straight

Parrott C.M. Parrott 1951 curved

Phillips 1973 straight

Robertshaw straight

Seward straight
curved, with integrated
Siker 1956
mirror

Soper R.I. Soper 1947 straight

Vie Scope N. Vasan 2016 Direct Line of Sight

Wis-Hipple straight

Wisconsin straight

Fiberoptic laryngoscopes
Besides the conventional laryngoscopes, many other devices have been developed as alternatives to direct
laryngoscopy. These include a number of indirect fiberoptic viewing laryngoscopes such as the flexible
fiberoptic bronchoscope. The flexible fiberoptic bronchoscope or rhinoscope can be used for office-based
diagnostics or for tracheal intubation. The patient can remain conscious during the procedure, so that the
vocal folds can be observed during phonation. Surgical instruments passed through the scope can be used
for performing procedures such as biopsies of suspicious masses. These instruments have become
indispensable within the otolaryngology, pulmonology and anesthesia communities.
Other available fiberoptic devices include the Bullard scope,[24] UpsherScope,[25][26] and the
WuScope.[27] These devices are widely employed for tracheal intubation, especially in the setting of the
difficult intubation (see below).

Video laryngoscope
The conventional direct laryngoscope uses a line of sight provided
by a rigid viewing instrument with a light on the blade or intra-oral
portion which requires a direct view of the target larynx; this view
is clearly seen in 80-90% of attempts. The frequent failure of direct
laryngoscopy to provide an adequate view for tracheal intubation
led to the development of alternative devices such as the lighted
stylet, and a number of indirect fiberoptic viewing laryngoscopes,
such as the fiberscope, Bullard scope, Upsher scope, and the
WuScope. Though these devices can be effective alternatives to
direct laryngoscopy, they each have certain limitations, and none of
them is effective under all circumstances. One important limitation
commonly associated with these devices is fogging of the lens.[28]
In an attempt to address some of these limitations, Jon Berall, a
New York City internist and emergency medicine physician,
designed the camera screen straight video laryngoscope in 1998.
The first true video laryngoscope Glidescope was produced in
1999 and a production version with 60 degree angle, an onboard
heater, and a custom screen was first sold in dec 2000. The true
video laryngoscope has a camera on the blade with no intervening
fiberoptic components. The concept is important because it is
simpler to produce and handle the resultant images from CMOS
cameras. The integrated camera leads to a series of low cost Glidescope video laryngoscope,
variants that are not possible with the hybrid Fiberoptic units. showing 60-degree angulated blade.
The CMOS active pixel sensor
(CMOS APS) video camera and light
GlideScope source are located at the point of
angulation of the blade. An
In 2001, the GlideScope (designed by vascular and general surgeon anesthesia machine is visible on the
John Allen Pacey) became the first commercially available video high resolution LCD monitor.
laryngoscope. It incorporates a high resolution digital camera,
connected by a video cable to a high resolution LCD monitor. It
can be used for tracheal intubation to provide controlled mechanical
ventilation, as well as for removal of foreign bodies from the
airway. GlideScope owes its superior results to a combination of
five key factors:

1. The steep 60-degree angulation of its blade improves

the view of the glottis by reducing the requirement for
anterior displacement of the tongue.
2. The CMOS APS digital camera is located at the point of
angulation of the blade (rather than at the tip). This
placement allows the operator to more effectively view Anesthesiologist using GlideScope
the field in front of the camera. video laryngoscope to intubate the
3. The video camera is recessed for protection from blood trachea of a patient with challenging
and secretions which might otherwise obstruct the view. airway anatomy
 4. The video camera has a relatively wide viewing angle of 50 degrees.
5. The heated lens innovation helps to prevent fogging of the lens, which might otherwise
obscure the view.

Tracheal intubation with the GlideScope can be facilitated by the use of the Verathon Stylet, a rigid stylet
that is curved to follow the 60° angulation of the blade.[29] To achieve a 99% successful rate of intubation
with the GlideScope requires the operator to acquire a new skill set with this stylet.

In a 2003 study, the authors noted that the GlideScope provided adequate vision of the glottis (Cormack
and Lehane grade I-II) [30][31] even when the oral, pharyngeal and laryngeal axes could not be optimally
aligned due to the presence of a cervical collar. Despite this significant limitation, the average time to
intubate the trachea with the GlideScope was only 38 seconds.[29] In 2005, the first major clinical study
comparing the Glidescope to the conventional laryngoscope was published. In 133 patients in whom both
Glidescope and conventional laryngoscopy were performed, excellent or good laryngeal exposure was
obtained in 124/133 (93%) of Glidescope laryngoscopy patients, compared with only 98/133 (74%) of
patients in whom conventional laryngoscopy was used. Intubation was successful in 128/133 (96%) of
Glidescope laryngoscopy patients.[32] These early results suggest that this device may be a useful
alternative in the management of difficult tracheal intubation.

The Verathon design team later produced the Ranger Video Laryngoscope for a United States Air Force
requirement that is now rolling forward into EMS and military use. The Cobalt series of GlideScope then
introduced a single-use variant that encompasses weights from 1000 grams to morbid obesity and is
successful in many airway syndromes as well. The GlideScope Ranger is a variant designed for use in pre-
hospital airway management including air, land, and sea applications. This device weighs 1.5 pounds, and
is waterproof as well as airworthy to 20,000 feet altitude. The GlideScope Cobalt is a variant that has a
reusable video camera with light-emitting core which has a disposable or single use external shell for
prevention of cross infection.

In August 2009, the team at Verathon collaborated with Professor John Sakles from the University of
Arizona Emergency Department in achieving the world's first tracheal intubation conducted with the
assistance of telemedicine technology. During this demonstration, Sakles and the University of Arizona
Telemedicine service guided physicians in a rural hospital as they performed a tracheal intubation using the
GlideScope.

Other video laryngoscopes

Several types of video laryngoscopes are also currently available, such as the Truview PCD-R
Manufactured by Truphatek Israel, Glidescope,[29][32] McGrath laryngoscope,[33] Daiken Medical
Coopdech C-scope VLP-100,[34] the Storz C-Mac,[35] Pentax-AWS(or Airway Scope),[36][37][38][39][40]
Video Macintosh Intubating Laryngoscope System (VMS),[41] the Berci DCI,[42] and the Copilot VL.[43]
These laryngoscopes employ a variety of features such as a monitor on the handle and or channels to assist
in guiding the endotracheal tube into the trachea. The superior performance of video laryngoscopes in
airway management where cervical spine injury is possible has raised the question of whether these scopes
should supersede direct laryngoscopy in routine airway management.[29] Further evidence in support of
videolaryngoscopy has accumulated over the years, indicating a favourable risk profile for video
laryngoscopes over direct laryngoscopes.[44]

Other noninvasive intubation devices

Other "noninvasive" devices which can be employed to assist in tracheal intubation are the laryngeal mask
airway[45][46][47][48][49][50][51] (Some types of which may be used as a conduit for endotracheal tube
placement), the lighted stylet,[52][53] and the AirTraq.[54] Due to the widespread availability of such
devices, the technique of blind digital intubation[55] of the trachea is rarely practiced today, though it may
still be useful in emergency situations under austere conditions such as natural or man-made disasters.[56]

Complications
Cases of mild or severe injury caused by rough and inexperienced use of laryngoscopes have been
reported. These include minor damage to the soft tissues within the throat which causes a sore throat after
the operation to major injuries to the larynx and pharynx causing permanent scarring, ulceration and
abscesses if left untreated. Additionally, there is a risk of causing tooth damage.

Etymology and pronunciation

The word laryngoscopy uses combining forms of laryngo- and -scopy.

References
1. Hunting, Penelope (2002). The history of the Royal Society of Medicine. RSM Press. p. 79.
ISBN 978-1-85315-497-3.
2. Koltai PJ, Nixon RE (1989). "The story of the laryngoscope". Ear, Nose, & Throat Journal. 68
(7): 494–502. PMID 2676465 (https://pubmed.ncbi.nlm.nih.gov/2676465).
3. Bailey B (August 1996). "Laryngoscopy and laryngoscopes--who's first?: the forefathers/four
fathers of laryngology". Laryngoscope. 106 (8): 939–43. doi:10.1097/00005537-199608000-
00005 (https://doi.org/10.1097%2F00005537-199608000-00005). PMID 8699905 (https://pu
bmed.ncbi.nlm.nih.gov/8699905). S2CID 32925553 (https://api.semanticscholar.org/CorpusI
D:32925553).
4. Stark, James (2003). Bel canto: a history of vocal pedagogy. University of Toronto Press, p.
5. ISBN 0-8020-8614-4
5. García, Manuel (1855). "Observations on the Human Voice" (https://books.google.com/book
s?id=o6PYNM7RNwkC&pg=PA399). Proceedings of the Royal Society of London. 7 (60):
399–410. doi:10.1098/rspl.1854.0094 (https://doi.org/10.1098%2Frspl.1854.0094).
JSTOR 111815 (https://www.jstor.org/stable/111815). PMC 5180321 (https://www.ncbi.nlm.n
ih.gov/pmc/articles/PMC5180321). PMID 30163547 (https://pubmed.ncbi.nlm.nih.gov/30163
547). Retrieved 28 August 2010.
6. American Otological Society (1905). The Laryngoscope. Volume 15, pp. 402–403
7. Radomski, Teresa (2005). "Manuel García (1805–1906): A bicentenary reflection" (http://ww
w.harmonicorde.com/Radomski%20Australian%20Voice.pdf) (PDF). Australian Voice. 11:
25–41. Retrieved 28 August 2010.
8. "Con ciencia - Manuel Patricio García" (http://www.rtve.es/alacarta/videos/con-ciencia/cienci
a-manuel-patricio-garci/2352708/). 27 January 2014.
9. Hirsch NP, Smith GB, Hirsch PO (January 1986). "Alfred Kirstein. Pioneer of direct
laryngoscopy" (https://doi.org/10.1111%2Fj.1365-2044.1986.tb12702.x). Anaesthesia. 41
(1): 42–5. doi:10.1111/j.1365-2044.1986.tb12702.x (https://doi.org/10.1111%2Fj.1365-2044.
1986.tb12702.x). PMID 3511764 (https://pubmed.ncbi.nlm.nih.gov/3511764).
10. Morell Mackenzie (1888). The case of Emperor Frederick III.: full official reports by the
German physicians and by Sir Morell Mackenzie (https://books.google.com/books?id=G2DT
AAAAMAAJ&pg=PA167). New York: Edgar S. Werner. p. 167. Retrieved 27 August 2010.
11. Burkle CM, Zepeda FA, Bacon DR, Rose SH (2004). "A historical perspective on use of the
laryngoscope as a tool in anesthesiology" (https://doi.org/10.1097%2F00000542-20040400
0-00034). Anesthesiology. 100 (4): 1003–6. doi:10.1097/00000542-200404000-00034 (http
s://doi.org/10.1097%2F00000542-200404000-00034). PMID 15087639 (https://pubmed.ncb
i.nlm.nih.gov/15087639). S2CID 36279277 (https://api.semanticscholar.org/CorpusID:36279
277).
12. Jackson, Chevalier (1996). "The technique of insertion of intratracheal insufflation tubes".
Pediatric Anesthesia. 6 (3): 230. doi:10.1111/j.1460-9592.1996.tb00434.x (https://doi.org/10.
1111%2Fj.1460-9592.1996.tb00434.x). S2CID 72582327 (https://api.semanticscholar.org/C
orpusID:72582327).
13. Zeitels SM (March 1998). "Chevalier Jackson's contributions to direct laryngoscopy". J
Voice. 12 (1): 1–6. doi:10.1016/S0892-1997(98)80069-6 (https://doi.org/10.1016%2FS0892-
1997%2898%2980069-6). PMID 9619973 (https://pubmed.ncbi.nlm.nih.gov/9619973).
14. Chevalier Jackson (1922). "I: Instrumentarium" (http://mybebook.com/download_free_ebook/
jackson-chevalier-1865-1958_ebooks/bronchoscopy-and-esophagoscopya-manual-of-peror
al-endoscopy-and-laryngeal-surgery/ebook13336.pdf) (PDF). A manual of peroral
endoscopy and laryngeal surgery. Philadelphia: W.B. Saunders Company. pp. 17–52.
ISBN 978-1-4326-6305-6. Retrieved 27 August 2010.
15. Janeway, Henry H. (1913). "Intra-Tracheal Anesthesia from the Standpoint of the Nose,
Throat and Oral Surgeon with a Description of a New Instrument for Catheterizing the
Trachea.*" (https://zenodo.org/record/1448738). The Laryngoscope. 23 (11): 1082–1090.
doi:10.1288/00005537-191311000-00009 (https://doi.org/10.1288%2F00005537-19131100
0-00009). S2CID 71549386 (https://api.semanticscholar.org/CorpusID:71549386).
16. Scott J, Baker PA (2009). "How did the Macintosh laryngoscope become so popular?" (http
s://doi.org/10.1111%2Fj.1460-9592.2009.03026.x). Pediatric Anesthesia. 19 (Suppl 1): 24–
9. doi:10.1111/j.1460-9592.2009.03026.x (https://doi.org/10.1111%2Fj.1460-9592.2009.030
26.x). PMID 19572841 (https://pubmed.ncbi.nlm.nih.gov/19572841). S2CID 6345531 (https://
api.semanticscholar.org/CorpusID:6345531).
17. Robert A. Miller (1941). "A new laryngoscope" (https://doi.org/10.1097%2F00000542-19410
5000-00008). Anesthesiology. 2 (3): 317–20. doi:10.1097/00000542-194105000-00008 (http
s://doi.org/10.1097%2F00000542-194105000-00008). S2CID 72555028 (https://api.semanti
cscholar.org/CorpusID:72555028).
18. Somchai Amornyotin; Ungkab Prakanrattana; Phongthara Vichitvejpaisal; Thantima Vallisut;
Neunghathai Kunanont; Ladda Permpholprasert (2010). "Comparison of the Clinical Use of
Macintosh and Miller Laryngoscopes for Orotracheal Intubation by Second-Month Nurse
Students in Anesthesiology" (http://downloads.hindawi.com/journals/arp/2010/432846.pdf)
(PDF). Anesthesiology Research and Practice. 2010: 1–5. doi:10.1155/2010/432846 (https://
doi.org/10.1155%2F2010%2F432846). PMC 2911595 (https://www.ncbi.nlm.nih.gov/pmc/art
icles/PMC2911595). PMID 20700430 (https://pubmed.ncbi.nlm.nih.gov/20700430).
Retrieved 27 August 2010.
19. James M. Berry (2007). "Chapter 16: Conventional (laryngoscopic) orotracheal and
nasotracheal intubation (single-lumen tube)" (https://books.google.com/books?id=uUVYjVU
exKUC&q=Benumof's+airway+management:+principles+and+practice). In Benumof JL (ed.).
Benumof's airway management: principles and practice (2nd ed.). Philadelphia: Mosby-
Elsevier. pp. 379–392. ISBN 978-0-323-02233-0. Retrieved 28 August 2010.
20. Bainton, CR (November 1987). "A new laryngoscope blade to overcome pharyngeal
obstruction". Anesthesiology. 67 (5): 767–70. doi:10.1097/00000542-198711000-00021 (htt
ps://doi.org/10.1097%2F00000542-198711000-00021). PMID 3674475 (https://pubmed.ncb
i.nlm.nih.gov/3674475).
21. Robert Reynolds Macintosh (1943). "A new laryngoscope" (https://zenodo.org/record/15616
57). The Lancet. 1 (6): 205. doi:10.1016/S0140-6736(02)95524-8 (https://doi.org/10.1016%2
FS0140-6736%2802%2995524-8).
22. Magill, I.W. (1926). "An Improved Laryngoscope for Anæsthetists". The Lancet. 207 (5349):
500. doi:10.1016/S0140-6736(01)17109-6 (https://doi.org/10.1016%2FS0140-6736%2801%
2917109-6).
23. Cook, TM; Tuckey, JP (10 May 1996). "A comparison between the Macintosh and the McCoy
laryngoscope blades" (https://doi.org/10.1111%2Fj.1365-2044.1996.tb14971.x).
Anaesthesia. 51 (10): 977–980. doi:10.1111/j.1365-2044.1996.tb14971.x (https://doi.org/10.
1111%2Fj.1365-2044.1996.tb14971.x). PMID 8984878 (https://pubmed.ncbi.nlm.nih.gov/89
84878).
24. Gorback MS (1991). "Management of the challenging airway with the Bullard laryngoscope".
Journal of Clinical Anesthesia. 3 (6): 473–7. doi:10.1016/0952-8180(91)90096-6 (https://doi.
org/10.1016%2F0952-8180%2891%2990096-6). PMID 1760171 (https://pubmed.ncbi.nlm.ni
h.gov/1760171).
25. Pearce AC, Shaw S, Macklin S (1996). "Evaluation of the Upsherscope. A new rigid
fibrescope" (https://doi.org/10.1111%2Fj.1365-2044.1996.tb12565.x). Anaesthesia. 51 (6):
561–4. doi:10.1111/j.1365-2044.1996.tb12565.x (https://doi.org/10.1111%2Fj.1365-2044.19
96.tb12565.x). PMID 8694210 (https://pubmed.ncbi.nlm.nih.gov/8694210). S2CID 37485173
(https://api.semanticscholar.org/CorpusID:37485173).
26. Fridrich P, Frass M, Krenn CG, Weinstabl C, Benumof JL, Krafft P (1997). "The
UpsherScope in routine and difficult airway management: a randomized, controlled clinical
trial" (https://doi.org/10.1097%2F00000539-199712000-00036). Anesthesia & Analgesia. 85
(6): 1377–81. doi:10.1097/00000539-199712000-00036 (https://doi.org/10.1097%2F000005
39-199712000-00036). PMID 9390612 (https://pubmed.ncbi.nlm.nih.gov/9390612).
S2CID 70552381 (https://api.semanticscholar.org/CorpusID:70552381).
27. Wu TL, Chou HC (1994). "A new laryngoscope: the combination intubating device".
Anesthesiology. 81 (4): 1085–7. doi:10.1097/00000542-199410000-00044 (https://doi.org/1
0.1097%2F00000542-199410000-00044). PMID 7943825 (https://pubmed.ncbi.nlm.nih.gov/
7943825).
28. Foley LJ, Ochroch EA (July 2000). "Bridges to establish an emergency airway and alternate
intubating techniques". Crit Care Clin. 16 (3): 429–44, vi. doi:10.1016/S0749-
0704(05)70121-4 (https://doi.org/10.1016%2FS0749-0704%2805%2970121-4).
PMID 10941582 (https://pubmed.ncbi.nlm.nih.gov/10941582).
29. Agrò F, Barzoi G, Montecchia F (May 2003). "Tracheal intubation using a Macintosh
laryngoscope or a GlideScope in 15 patients with cervical spine immobilization" (https://doi.
org/10.1093%2Fbja%2Faeg560). Br J Anaesth. 90 (5): 705–6. doi:10.1093/bja/aeg560 (http
s://doi.org/10.1093%2Fbja%2Faeg560). PMID 12697606 (https://pubmed.ncbi.nlm.nih.gov/1
2697606).
30. Cormack RS, Lehane J (November 1984). "Difficult tracheal intubation in obstetrics" (https://
doi.org/10.1111%2Fj.1365-2044.1984.tb08932.x). Anaesthesia. 39 (11): 1105–11.
doi:10.1111/j.1365-2044.1984.tb08932.x (https://doi.org/10.1111%2Fj.1365-2044.1984.tb08
932.x). PMID 6507827 (https://pubmed.ncbi.nlm.nih.gov/6507827).
31. Ernst Zadrobilek (28 October 2009). "The Cormack-Lehane classification: twenty-fifth
anniversary of the first published description" (http://www.ijam.at/volume05/historicalnote02/
default.htm). Internet Journal of Airway Management. 5. Retrieved 4 August 2010.
32. Cooper RM, Pacey JA, Bishop MJ, McCluskey SA (February 2005). "Early clinical
experience with a new videolaryngoscope (GlideScope) in 728 patients" (https://doi.org/10.1
007%2FBF03027728). Can J Anaesth. 52 (2): 191–8. doi:10.1007/BF03027728 (https://doi.o
rg/10.1007%2FBF03027728). PMID 15684262 (https://pubmed.ncbi.nlm.nih.gov/15684262).
33. Shippey B, Ray D, McKeown D (2008). "Use of the McGrath videolaryngoscope in the
management of difficult and failed tracheal intubation" (https://doi.org/10.1093%2Fbja%2Fae
m303). British Journal of Anaesthesia. 100 (1): 116–9. doi:10.1093/bja/aem303 (https://doi.or
g/10.1093%2Fbja%2Faem303). PMID 17959584 (https://pubmed.ncbi.nlm.nih.gov/1795958
4).
34. Daiken Medical Co., Ltd. (2007). "Coopdech video laryngoscope portable VLP-100" (https://
web.archive.org/web/20110216044108/http://baobabmedical.com.au/Pdfs/portablecolourvid
eo.pdf) (PDF). Osaka, Japan: Daiken Medical Co., Ltd. Archived from the original (http://ww
w.baobabmedical.com.au/Pdfs/portablecolourvideo.pdf) (PDF) on 16 February 2011.
Retrieved 27 August 2010.
35. Boedeker BH, Berg BW, Bernhagen MA, Murray WB (2009). "Endotracheal intubation
comparing a prototype Storz CMAC and a glidescope videolaryngoscope in a medical
transport helicopter - a pilot study" (http://booksonline.iospress.nl/Extern/EnterMedLine.asp
x?ISSN=0926-9630&Volume=142&SPage=37). Studies in Health Technology and
Informatics. 142: 37–9. PMID 19377109 (https://pubmed.ncbi.nlm.nih.gov/19377109).
Retrieved 27 August 2010.
36. Pentax Medical Company (6 July 2006). "Airway Scope AWS-S100, Rigid Video
Laryngoscope for Intubation" (https://web.archive.org/web/20100728075509/http://www.pent
ax.co.jp/english/news/2006/200633.html). Montvale, New Jersey: Pentax Medical Company.
Archived from the original (http://www.pentax.co.jp/english/news/2006/200633.html) on 28
July 2010. Retrieved 27 August 2010.
37. Pentax Medical Company. "Pentax AWS" (https://web.archive.org/web/20110715063400/htt
p://www.pentaxmedical.com/brochures/PentaxAWS.pdf) (PDF). Montvale, New Jersey:
Pentax Medical Company. Archived from the original (http://www.pentaxmedical.com/brochu
res/PentaxAWS.pdf) (PDF) on 15 July 2011. Retrieved 27 August 2010.
38. Suzuki A, Toyama Y, Katsumi N, Kunisawa T, Sasaki R, Hirota K, Henderson JJ, Iwasaki H
(2008). "The Pentax-AWS((R)) rigid indirect video laryngoscope: clinical assessment of
performance in 320 cases" (https://doi.org/10.1111%2Fj.1365-2044.2008.05452.x).
Anaesthesia. 63 (6): 641–7. doi:10.1111/j.1365-2044.2008.05452.x (https://doi.org/10.111
1%2Fj.1365-2044.2008.05452.x). PMID 18477277 (https://pubmed.ncbi.nlm.nih.gov/184772
77).
39. Malik MA, O'Donoghue C, Carney J, Maharaj CH, Harte BH, Laffey JG (2009). "Comparison
of the Glidescope, the Pentax AWS, and the Truview EVO2 with the Macintosh laryngoscope
in experienced anaesthetists: a manikin study" (https://doi.org/10.1093%2Fbja%2Faen342).
British Journal of Anaesthesia. 102 (1): 128–34. doi:10.1093/bja/aen342 (https://doi.org/10.1
093%2Fbja%2Faen342). PMID 19059923 (https://pubmed.ncbi.nlm.nih.gov/19059923).
40. Asai T, Enomoto Y, Shimizu K, Shingu K, Okuda Y (2008). "The Pentax-AWS video-
laryngoscope: the first experience in one hundred patients". Anesthesia & Analgesia. 106
(1): 257–9, table of contents. doi:10.1213/01.ane.0000287647.46165.bc (https://doi.org/10.1
213%2F01.ane.0000287647.46165.bc). PMID 18165587 (https://pubmed.ncbi.nlm.nih.gov/1
8165587). S2CID 32788869 (https://api.semanticscholar.org/CorpusID:32788869).
41. Kaplan MB, Ward DS, Berci G (2002). "A new video laryngoscope-an aid to intubation and
teaching" (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4803417). Journal of Clinical
Anesthesia. 14 (8): 620–6. doi:10.1016/S0952-8180(02)00457-9 (https://doi.org/10.1016%2
FS0952-8180%2802%2900457-9). PMC 4803417 (https://www.ncbi.nlm.nih.gov/pmc/article
s/PMC4803417). PMID 12565125 (https://pubmed.ncbi.nlm.nih.gov/12565125).
42. Low D, Healy D, Rasburn N (2008). "The use of the BERCI DCI Video Laryngoscope for
teaching novices direct laryngoscopy and tracheal intubation" (https://doi.org/10.1111%2Fj.1
365-2044.2007.05323.x). Anaesthesia. 63 (2): 195–201. doi:10.1111/j.1365-
2044.2007.05323.x (https://doi.org/10.1111%2Fj.1365-2044.2007.05323.x). PMID 18211452
(https://pubmed.ncbi.nlm.nih.gov/18211452).
43. Tydlaska, Jay. "Introducing the CoPilotVL" (http://copilotvl.com). Magaw LLC. Retrieved
5 August 2011.
44. Hansel J, Rogers AM, Lewis SR, Cook TM, Smith AF (April 2022). "Videolaryngoscopy
versus direct laryngoscopy for adults undergoing tracheal intubation" (https://www.ncbi.nlm.n
ih.gov/pmc/articles/PMC8978307). Cochrane Database Syst Rev. 2022 (4): CD011136.
doi:10.1002/14651858.CD011136.pub3 (https://doi.org/10.1002%2F14651858.CD011136.p
ub3). PMC 8978307 (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8978307).
PMID 35373840 (https://pubmed.ncbi.nlm.nih.gov/35373840).
45. Brain AI (August 1983). "The laryngeal mask--a new concept in airway management" (http
s://doi.org/10.1093%2Fbja%2F55.8.801). Br J Anaesth. 55 (8): 801–5.
doi:10.1093/bja/55.8.801 (https://doi.org/10.1093%2Fbja%2F55.8.801). PMID 6349667 (http
s://pubmed.ncbi.nlm.nih.gov/6349667). S2CID 21057581 (https://api.semanticscholar.org/Co
rpusID:21057581).
46. Brain AI (1985). "Three cases of difficult intubation overcome by the laryngeal mask airway"
(https://doi.org/10.1111%2Fj.1365-2044.1985.tb10788.x). Anaesthesia. 40 (4): 353–5.
doi:10.1111/j.1365-2044.1985.tb10788.x (https://doi.org/10.1111%2Fj.1365-2044.1985.tb10
788.x). PMID 3890603 (https://pubmed.ncbi.nlm.nih.gov/3890603).
47. Benumof JL (February 1992). "Use of the laryngeal mask airway to facilitate fiberscope-
aided tracheal intubation" (https://doi.org/10.1213%2F00000539-199202000-00034).
Anesth. Analg. 74 (2): 313–5. doi:10.1213/00000539-199202000-00034 (https://doi.org/10.1
213%2F00000539-199202000-00034). PMID 1731560 (https://pubmed.ncbi.nlm.nih.gov/17
31560).
48. Lim SL, Tay DH, Thomas E (March 1994). "A comparison of three types of tracheal tube for
use in laryngeal mask assisted blind orotracheal intubation" (https://doi.org/10.1111%2Fj.13
65-2044.1994.tb03435.x). Anaesthesia. 49 (3): 255–7. doi:10.1111/j.1365-
2044.1994.tb03435.x (https://doi.org/10.1111%2Fj.1365-2044.1994.tb03435.x).
PMID 7848398 (https://pubmed.ncbi.nlm.nih.gov/7848398).
49. Theroux MC, Kettrick RG, Khine HH (February 1995). "Laryngeal mask airway and fiberoptic
endoscopy in an infant with Schwartz-Jampel syndrome" (https://doi.org/10.1097%2F00000
542-199502000-00044). Anesthesiology. 82 (2): 605. doi:10.1097/00000542-199502000-
00044 (https://doi.org/10.1097%2F00000542-199502000-00044). PMID 7856930 (https://pu
bmed.ncbi.nlm.nih.gov/7856930).
50. Inada T, Fujise K, Tachibana K, Shingu K (1995). "Orotracheal intubation through the
laryngeal mask airway in paediatric patients with Treacher-Collins syndrome". Paediatr
Anaesth. 5 (2): 129–32. doi:10.1111/j.1460-9592.1995.tb00260.x (https://doi.org/10.1111%2
Fj.1460-9592.1995.tb00260.x). PMID 7489423 (https://pubmed.ncbi.nlm.nih.gov/7489423).
S2CID 36051869 (https://api.semanticscholar.org/CorpusID:36051869).
51. Lee JJ, Lim BG, Lee MK, Kong MH, Kim KJ, Lee JY (March 2012). "Fiberoptic intubation
through a laryngeal mask airway as a management of difficult airwary due to the fusion of
the entire cervical spine - A report of two cases -" (https://www.ncbi.nlm.nih.gov/pmc/articles/
PMC3315659). Korean J Anesthesiol. 62 (3): 272–6. doi:10.4097/kjae.2012.62.3.272 (http
s://doi.org/10.4097%2Fkjae.2012.62.3.272). PMC 3315659 (https://www.ncbi.nlm.nih.gov/p
mc/articles/PMC3315659). PMID 22474556 (https://pubmed.ncbi.nlm.nih.gov/22474556).
52. Zbinden S, Schüpfer G (1989). "Tube-Stat®: ein nützliches Hilfsmittel bei schwieriger
Intubation" [The Tube-Stat: a useful aid in difficult intubation]. Der Anaesthesist (in German).
38 (3): 140–3. PMID 2719227 (https://pubmed.ncbi.nlm.nih.gov/2719227).
53. Davis L, Cook-Sather SD, Schreiner MS (2000). "Lighted stylet tracheal intubation: a review"
(https://doi.org/10.1097%2F00000539-200003000-00044). Anesthesia & Analgesia. 90 (3):
745–56. doi:10.1097/00000539-200003000-00044 (https://doi.org/10.1097%2F00000539-2
00003000-00044). PMID 10702469 (https://pubmed.ncbi.nlm.nih.gov/10702469).
S2CID 26644781 (https://api.semanticscholar.org/CorpusID:26644781).
54. Maharaj CH, Costello JF, McDonnell JG, Harte BH, Laffey JG (2007). "The Airtraq as a
rescue airway device following failed direct laryngoscopy: a case series". Anaesthesia. 62
(6): 598–601. doi:10.1111/j.1365-2044.2007.05036.x (https://doi.org/10.1111%2Fj.1365-204
4.2007.05036.x). PMID 17506739 (https://pubmed.ncbi.nlm.nih.gov/17506739).
S2CID 21106547 (https://api.semanticscholar.org/CorpusID:21106547).
55. Norman R. James (1950). "Blind Intubation". Anaesthesia. 5 (3): 159–160.
doi:10.1111/j.1365-2044.1950.tb12674.x (https://doi.org/10.1111%2Fj.1365-2044.1950.tb12
674.x). S2CID 221389855 (https://api.semanticscholar.org/CorpusID:221389855).
56. Chris C. Christodoulou; Michael F. Murphy; Orlando R. Hung (2007). "Chapter 17: Blind
digital intubation" (https://books.google.com/books?id=uUVYjVUexKUC&q=Benumof's+airw
ay+management:+principles+and+practice). In Benumof JL (ed.). Benumof's airway
management: principles and practice (2nd ed.). Philadelphia: Mosby-Elsevier. pp. 393–398.
ISBN 978-0-323-02233-0. Retrieved 28 August 2010.

External links

Retrieved from "https://en.wikipedia.org/w/index.php?title=Laryngoscopy&oldid=1183965689"