**Abstract**

Although medical services in aviation have evolved over years based on our understanding of physiology, advancement in monitoring technology but airway management was only recently studied with a focus on space environment. The barometric pressure of ambient air declines as altitude increases, while the volume of air in a confined space will increase according to Boyle law, and therefore oxygen concentration remains at a constant 21%. Altitude sensitive equipment includes endotracheal and tracheostomy cuffs, pneumatic anti shock garments, air splints, colostomy bags, Foley catheters, orogastric and nasogastric tubes, ventilators, invasive monitors, and intra-aortic balloon pumps. The microgravity reduces the body compensation capacity for hemorrhage, while the redistribution of the blood can affect intubation by causing facial edema. Another change is the decreased gastric emptying during aviation. Acute respiratory failure, hypoxemia or inadequate ventilation and protection of the airway in a patient with impaired consciousness are common indications for advanced airway management in aviation. Airway management requires adequate training to maintain excellent medical care during aviation. Tracheal intubation using laryngoscopy would be difficult in microgravity, since the force exerted by the laryngoscope causes the head and neck move out of the field of vision by lever effect exerted on the head and generated through the laryngoscope blade by hand generating a lack of stability, resulting in the difficulty to insert the tracheal tube. While on the ground with the help of gravity, an adequate positioning of the patient is facilitated to achieve alignment of the laryngeal, pharyngeal and oral axes, which is known as sniffing position that allows visualization of the vocal cords and supraglottic structures allowing the introduction of an endotracheal tube.

**Keywords:** medical aviation, microgravity, weightless environment, stratosphere, high altitude, near space, space medicine

## **1. Introduction**

Space exploration is rapidly advancing and requiring a parallel advancement of medical services that can be provided in aviation for any kind of medical issues that may arise during the space flight. The physiology of human body is definitely affected by the change in gravity during space flights, this why the extent of physiological changes, the required monitoring and intervention should be carefully tailored based on the physiological response to the space environment and the

underlying medical conditions. Although medical services in aviation has evolved over years based on our understanding of physiology, advancement in monitoring technology but airway management was only recently studied with a focus on space environment. Airway management and other hemodynamic goals parameters, especially during medical air transport and aviation put the patient and medical team under unfamiliar and extreme physiological conditions, with detrimental clinical sequalae. In this chapter will cover the airway management in aviation with high emphasis on physiological changes and he preferred airway management techniques during air transport and aviation conditions.
