When oxygenation is difficult or impossible, critical decision-making and immediate management to correct hypoxemia is of the utmost importance to avoid major morbidity and mortality. Failure to oxygenate in children most commonly results from functional airway obstruction. Functional airway obstruction can occur in many different areas of the pediatric airway. Upper airway obstruction in babies is often due to a blocked nose and having the tongue stuck to the hard palate. Bronchospasm in asthmatics and tracheomalacia in children with previous tracheoesophageal fistulae are examples of lower airway obstruction. However, laryngospasm is by far the most common functional airway problem. Laryngospasm is easily managed by deepening anesthesia and/or administering succinylcholine. If management is delayed, severe hypoxia, bradycardia, and even cardiac arrest may occur. Invasive airway access through the front of the neck directly into the trachea is not indicated in these situations. This chapter will focus on the “can’t intubate, can’t oxygenate” (CICO) emergency caused by anatomical or pathological causes that necessitate invasive access through the front of the neck. Anatomical upper airway obstruction may be caused by congenital abnormalities, infection, swelling, and malignant or non-malignant growths of the upper airway. In the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society (NAP4), 75% of cases (43 out of 58) who required emergency invasive airway were patients with head and neck pathologies. Children presenting with severe upper airway obstruction secondary to anatomical or pathological conditions almost always have significant past medical histories. Therefore, their presentation should be easily distinguished from children with functional upper airway obstruction. Children with anatomical or pathological upper airway abnormalities may deteriorate gradually over time, or suddenly when their upper airway obstruction is aggravated by secondary infection or simple upper respiratory tract infection. Use of neuromuscular blockade or deepening anesthesia to manage anatomical or pathological obstruction could be detrimental in these deteriorating children as cessation of spontaneous ventilation could result in oxygenation failure. It is of utmost importance in these cases that spontaneous ventilation is maintained while securing the airway.