It has long been assumed in emergency airway management that the fundamental priorities are oxygenation and ventilation. Apart from instances of severe acidosis with compensatory respiratory alkalosis, ventilation is rarely as time critical as oxygenation. Desaturation and severe hypoxemia kills in seconds to minutes; the lack of ventilation causes a buildup of carbon dioxide and eventually acidosis, but it is only critical when patients start out severely acidotic (eg, diabetic ketoacidosis, salicylate overdose, acute renal failure, rhabdomyolysis, etc.).
Next to oxygenation, the priorities of emergency airway management are the management of fluids and the prevention of regurgitation and aspiration. Fluid regurgitation and vomiting has been underaddressed as a life threat in emergency airways.
Every seasoned clinician has encountered clinical situations where fluids impeded laryngoscopy and ventilation. Fluids are, in fact, the enemy of everything in the airway. They make direct and video laryngoscopy more challenging because they obscure landmarks. Look-around-the-curve video devices fail when fluid splatters across the optical element. Endoscopes are particularly useless when there is significant fluid in the airway as it is nearly impossible to keep the lens clean and discern an open pathway.
The most serious threat of fluids in the airway is not with laryngoscopy but rather with oxygenation. Apneic oxygenation, bag-mask ventilation, and rescue devices like the laryngeal mask airway and King LT all function poorly, if at all, when there is a high volume of fluid in the airway. In fact, there is only one airway management technique that can overcome massive fluids in the upper airway: cutting the neck. Cricothyrotomy, with a cuffed tube in the trachea, separates the airway from the shared aerodigestive tract through which all other means of oxygenation are dependent upon. When fluids are uncontrollable, it may be the only option and must be done quickly.