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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. |