الفهرس 
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Abstract
Successful and safe anesthetic airway management in pediatric
patients depend on an appreciation and clear understanding of the
physiological and anatomic differences between pediatric and adult
patients.
In proportion to the rest of the body, the infant’s head is
relatively larger. Both the tonsils and adenoid are a major cause of
upper airway obstruction in children. The tongue of the newborn is
larger in proportion to the rest of oral cavity. The larynx is situated
more cephalad at C3-4 in the infant. The infant epiglottis is longer,
stiff, and often described as omega or U shaped. The infant’s larynx is
funnel shaped with a narrow cricoid cartilage and the trachea is
shorter. The child’s relatively smaller airway results in increased airway
resistance. These differences can lead to susceptibility of airway
obstruction and difficult intubation.
Oxygen consumption in the neonate is almost twice the adult
value. Because infants have a compliant chest wall, decreased muscle
tone in deep sleep and sedated states lead to a significantly decreased
FRC up to 1O-15% of total lung capacity. Immature respiratory
control combined with an increased susceptibility to fatigue of the
respiratory muscles may be responsible for the increased risk of
postoperative apnea especially in preterm infants. Respiratory reserve
and apnea tolerance are strongly reduced and hypoxia may suddenly
appear and quickly worsen.
Summary
91
A difficult airway is generally defined as a situation in which a
clinician experiences difficulty with face mask ventilation,
laryngoscopy, or intubation. It is important to recognize circumstances
that may cause airway problems or difficult laryngoscopy. Airway
management can be adversely affected by conditions that involve head
enlargement. Children with craniofacial abnormalities (e.g. Pierre
Robin syndrome) can present considerable challenges in airway
management to anesthesiologists. Microstomia, macroglossia and
tongue masses are also important causes of difficult airway. Important
nasal, palatine, pharyngeal, laryngeal and Trache-obronchial
abnormalities should also be considered. Neck tumors and diseases
affecting cervical spine mobility represent real challenge for
anesthesiologists. Airway management in the airway trauma patient
or burns of neck and face can be particularly challenging
Inadequate mask seal, excessive gas leak, or excessive
resistance to the ingress or egress of gas are the main mechanisms of
difficult mask ventilation. The validated indicators of difficult BMV
can be easily recalled by using the mnemonic MOANS (Mask seal,
Obesity/Obstruction, Age, No teeth and Stiff lungs). Difficulty
with tracheal intubation is predominantly a consequence of failure to
see the larynx. The most widely used classification describing view of
the larynx is that described by Cormack and Lehane. An airway
assessment mnemonic, LEMON (Look externally, Evaluate the 3-3-2
rule, Mallampati, Obstruction and Neck mobility), takes into account
many of the anatomic factors associated with difficult intubation.
Difficulty in placing an EGD or performing cricothyrotomy are
assessed from the mnemonics RODS and SHORT consequently.
Summary
92
Laboratory and radiologic evaluation may be needed in airway
assessment.
Proper management of a patient’s airway during elective and
emergency situations is of vital importance for any clinician. Because
of this, the anesthesiologist should be familiar with airway aids and
devices available for airway management. Regarding ventilation
devices, many different types of face masks are available e.g. the
Rendell-Baker face mask. An oral or a nasal airway may be used to
achieve ventilation. Supraglottic airway devices also may be needed.
The most important SGD is the LMA. A variety of types have been
introduced into practice since the development of the original, now
called the LMA Classic.
Although it is usually assumed that the ’’gold standard’’ for
airway maintenance is the tracheal tube, but inserting a tracheal tube in
children is technically more challenging. Regarding intubation devices,
Fiberoptically assisted intubation is one of the most important
advances in difficult airway management since the introduction of the
laryngoscope. One significant recent development in advanced airway
management has been the emergence of video and optical
laryngoscopy. Moreover, optical and illuminating stylets are
important aids in difficult airway management.
Proper preoperative planning and preparation is the most
important process for managing the difficult airway patient. At least
one portable storage unit that contains specialized equipment for
difficult airway management should be readily available. If the airway
Summary
93
is predicted to be difficult to manage, a primary, preferred approach
should be developed, followed by the identification of alternative
approaches if the primary approach fails or is not feasible. Emergency
surgical airway access can be life saving in the cannot ventilate,
cannot intubate arm of the ASA DA algorithm. A simple step-wise
algorithm for the unexpected difficult pediatric airway based on an
adult Difficult Airway Society (DAS) protocol has been proposed. In
pediatric airway trauma, a multidisciplinary approach to the
management of the difficult trauma airway is necessary. The
management of the difficult pediatric airway does not end until the
plan for extubation has been established.
Documentation of the difficult airway is essential to provide
useful information for the subsequent time that the child requires
sedation/anesthesia.