Physiologically difficult airway: How to approach the difficulty beyond anatomy

Airway management during resuscitation

“…Because many hypoxemic patients have shunt or ventilation/ perfusion mismatch as a cause for their desaturation, they may not respond adequately to increases in delivered FiO2 and are thus at higher risk of peri-intubation hypoxemia. 4 If time permits, preoxygenation may facilitate efficient intubation. In the hypoxemic patient, inadequate preoxygenation worsens first-pass intubation success because desaturation during an intubation attempt forces clinicians to abort an intubation attempt to restore oxygen saturation.…”

“…An awake intubation technique may also be considered in the hypoxemic patient to permit spontaneous respiratory efforts throughout the intubation process. 4 An awake technique may also reduce aspiration risk in critically ill patients at risk for aspiration. If an awake technique is planned, peri-intubation oxygen delivery is probably best accomplished with a high-flow nasal cannula, which can deliver humidified oxygen at high-flow rates and does not obstruct access to the airway during the intubation attempt.…”

“…Due to their underlying pathology, patients presenting with hypoxemia are naturally at high risk of oxygen desaturation during endotracheal intubation and thus at high risk of hypoxemia-associated hemodynamic instability, anoxic brain injury, or cardiac arrest during intubation. Because many hypoxemic patients have shunt or ventilation/perfusion mismatch as a cause for their desaturation, they may not respond adequately to increases in delivered FiO2 and are thus at higher risk of peri-intubation hypoxemia 4 …”

“…An awake intubation technique may also be considered in the hypoxemic patient to permit spontaneous respiratory efforts throughout the intubation process 4 . An awake technique may also reduce aspiration risk in critically ill patients at risk for aspiration.…”

Synergic Difficulties in an Anticipated Physiologically and Anatomically Difficult Airway in a Trauma Patient: A Case Report

“…A physiologically difficult airway represents a unique challenge distinct from an anatomically difficult airway. As explored by Fonseca et al in their 2023 review [ 5 ], the challenges of a physiologically difficult airway are not the consequence of anatomical deviations impeding instrumented airway access, but rather physiological conditions that render the patient vulnerable to rapid desaturation, hemodynamic instability, or altered respiratory mechanics during intubation attempts. Common factors contributing to a physiologic difficult airway include severe hypoxemia, hypercarbia, acidemia, and elevated intracranial pressure.…”