Oropharyngeal Airway
Atslēgvārdi
Abstrakts
Acute respiratory failure is caused by a wide range of etiologies. Progression to cardiopulmonary arrest and ultimately death is likely in the absence of effective and timely airway management. Therefore, one of the primary goals of airway management is to provide adequate ventilation and oxygenation to avoid or halt the progression to cardiopulmonary arrest. Effective and timely airway management is also an essential component of successful cardiopulmonary resuscitation. Airway management is critical in the pediatric population as pediatric airway problems are commonly seen in pediatric and general emergency departments. Respiratory distress is the fourth most common chief complaint in children presenting to the emergency department. Initial steps in airway management include airway positioning maneuvers (for example, head-tilt-chin lift, jaw-thrust), suctioning, supplemental oxygen, and re-positioning of the airway if the previous steps are ineffective. Airway positioning maneuvers place the airway in a neutral position and help move the tongue and palatal tissues away from the posterior wall of the pharynx. When choosing an airway positioning maneuver, one must be cognizant of the possible presence or absence of a cervical spine injury. Suctioning assists with the removal of secretions that could be causing or contributing to airway obstruction. If these steps do not help in maintaining a patent airway or in providing adequate ventilation and oxygenation, then an airway adjunct should be utilized. Airway adjuncts are used to relieve or bypass an upper airway obstruction during airway management. However, upper airway obstruction may be present for several reasons, and airway adjuncts may not be able to relieve or bypass all types of obstruction. Upper airway obstruction may occur from anatomical causes such as choanal atresia, pathological causes such as a tonsillar abscess or adverse effects from patient management such as loss of airway patency during the administration of sedation and/or analgesia. There are also subsets of patients that are more prone to develop upper airway obstruction. Patients with obesity are at significant risk for upper airway obstruction due to altered upper airway anatomy. Pharyngeal tissues have increased fat deposition causing excess upper airway tissue and an increased likelihood of pharyngeal wall collapse resulting in airway obstruction. This can be exacerbated when patients with obesity are given drugs that depress the central nervous system or have other co-morbidities, such as obstructive sleep apnea (OSA) and/or obstructive hypoventilation syndrome (OHS). The presence of OSA and/or OHS can be associated with increased sensitivity to the respiratory depressant effects of sedatives and opioids increasing the tendency to obstruct the airway. Pediatric patients, in particular infants and young children, are susceptible to upper airway obstruction. This predisposition is due to the differences between pediatric and adult airways. Infants and young children have a relatively large occiput that causes neck flexion when lying supine. This results in a natural tendency to obstruct the upper airway. They have a proportionally large tongue relative to the size of their oral cavity which also causes a natural obstruction of the airway. Additionally, a shortened thyromental distance in this patient population brings the tongue into proximity of the soft palate. Consequently, this leads to obstruction of the airway. Lastly, compared to adults, infants and young children have larger adenoidal tissue, as well as, more distensible and compliant larger airways which predisposes them to airway obstruction. In general, by the age of eight, the pediatric airway is very similar to that of an adult airway. There are two types of airway adjuncts. One is an oropharyngeal airway, and the other is a nasopharyngeal airway. This article will summarize the former.