Weiss et al.: ENDOTRACHEAL INTUBATIONMONITORING
1205
course. No difficulties with the endoscopic equipment
during intubation or removal from the ETT were stat-
ed, except that the black coated endoscope within the
ETT compromised the recognition of the black ETT
depth-markings on small tubes.
retroflexion of the neck after direct laryngoscopy. Thus,
accurate final placement of the ETT at a safe distance
from the tracheal carina is essential, especially in
neonates and small children. However, clinical studies
in larger populations are needed to evaluate the benefit
of visualized ETT placement compared with conven-
tional methods in pediatric anesthesia or pediatric
intensive care.
An important benefit of the technique was that, in
six patients, the monitor view from the ETT tip
helped to guide the tube into the trachea. Although
the tip of the fibreoptic endoscope was not malleable
or steerable, the preformed, curved RAE tube, used in
these patients allowed to direct the ETT around the
floppy, large epiglottis, obstructing the view to the
cords. Although the operators were experienced with
video-optical intubation stylets from earlier intubation
mannequin studies, the familiar nature of the video-
assisted intubation technique was reflected by the high
success rate in all six patients.12 Because the fibreoptic
endoscope does not interfere with conventional intu-
bation, such an “optic cable” can be inserted prophy-
lactically within the ETT in high risk patients before
starting anesthesia. If unexpected difficulties with
laryngoscopy arise, it provides rapid endoscopic intu-
bation assistance, otherwise, it is used for immediate
confirmation of tracheal tube position.
The present technique allows monitoring of the
passage of the ETT through the larynx to the carina.
No information about performance of direct laryn-
goscopy are provided on the video display. In contrast,
video-transmission of the view from the distal laryn-
goscope blade as described by Roberts gives in addi-
tional display of all the anatomical structures during
direct laryngoscopy.1 3
A further limitation of the technique is the high
cost of the optical equipment. Fibreoptic endoscopy
for airway management is expensive and the equip-
ment requires much time for cleaning, sterilisation
and preparation. The presented ultrathin fibrescope is
a low-cost endoscope (1500 Can $) without the facil-
ity either to manipulate the tip or to perform suction.
Equipped with a proximal viewfinder or and light con-
nector, it can be used with existing video-endoscopy
monitoring systems in the OR or ICU.
Discussion
We have evaluated efficacy of monitoring the ETT tip
during endotracheal intubation in children using an
ultrathin video-fibreendoscopic system within the tra-
cheal tube. The main finding was, that video-intubo-
scopic monitoring in a teaching situation enabled the
supervisor to recognize and correct malpositioned
endotracheal tubes instantly.
Monitoring the tip of an endotracheal tube was first
published by Murphy 1967.7 He used the view from
the ETT tip achieved by a flexible, non-stearable chole-
dochoscope within the tube for nasal intubation.
Video-monitoring of the ETT tip was first reported by
Vacanti and Roberts in 1992.8 They placed a fibreoptic
endoscope adjacent to a malleable stylet in an oral
endotracheal tube and connected the endoscope to a
video-monitor system. The video view from the tube tip
was used to assess the effect of various manipulations on
access to the trachea during blind oral intubation.
The present intubation technique using an ultrathin,
lightweight fibreoptic endoscope to monitor the ETT
tip, provides a video-display from the intubation proce-
dure during conventional intubation without jeopardiz-
ing the operator or the intubation process. The main
advantage of video-intuboscopic intubation monitoring
in our study was rapid and reliable recognition and
instantly correction of accidentially malplaced endotra-
cheal tubes by the supervisor. Immediate recognition
and correction of an esophageal or bronchial inserted
tracheal tube is important to avoid potentially serious
complications. Thus, in addition to pulse oximetry and
capnography, the video-intuboscopic technique may
become a valuable aid for rapid tracheal tube position
confirmation in anesthesia teaching units or in high risk
patients requiring tracheal intubation.9,10
A further advantage of video-intuboscopic monitor-
ing was endoscopic adjustment of the tracheal tube tip
within the trachea. Alteration of the head position dur-
ing the operative course or placement of a tongue
depressor can result in considerable movement of the
ETT within the trachea of pediatric patients.11 Thus, an
initially well working tracheal tube in the lower or upper
trachea is at risk for endobronchial intubation or acci-
dental extubation with possible dislocation of the ETT
into the upper esophagus. In addition, an initially cor-
rectly placed endotracheal tube can become displaced
during removal of the laryngoscope blade and release of
In conclusion, video-intuboscopic monitoring of
tracheal intubation can facilitate supervision of intuba-
tion in pediatric patients and is useful for early recog-
nition and correction of malpositioned endotracheal
tubes. The better view of the cords obtained by the
video-endoscopic system during intubation provides a
valuable assist during difficult laryngoscopy.