**2. Indications of endotracheal intubation under emergency conditions**

In emergency conditions, equipment, technical skills, and quickness are very important when deciding on intubation indications at the bedside. Endotracheal intubation can be performed under emergency conditions in the following circumstances [6, 7, 25, 28, 29]:

• Apnea, respiratory failure.

who manages the difficult airway must recognize the patients who will face the airway problem, must plan to deal with the air, review the algorithms, and use the right agent for induction. Also, the emergency airway kit should be pulled to the bedside, and the end-tidal carbon dioxide values should be monitored for each patient [27, 28]. Although studies have emphasized in recent years that there are changes in the treatment of these patients after high-flow oxygen therapy, most of these patients need invasive mechanical ventilation and tracheal intubation [29]. When planning the treatment of these patients in the long term, the patient comfort should be improved by avoiding complications related to the endotracheal tube by

The most common complication of intubation at the bedside is life-threatening hypoxemia [29]. Despite regular preoxygenation, a desaturation can develop. For this reason, various strategies have been developed for the preoxygenation period when the patient is intubated [19]. The intubation stage can be classified into two steps. The first step is the preoxygenation stage, and the second step is the laryngoscopy stage which requires induction [31]. NIV improves preoxygenation and limits desaturation, but its disadvantage is that oxygen flow is separated from the patient during laryngoscopy. In patients with hypoxic respiratory failure, high-flow oxygen is generally used, and uninterrupted oxygen supply is its advantage during intubation [32, 33]. Apneic oxygenation seems to be superior when compared with high-flow oxygen and mask ventilation [34]. It should be noted that in situations where high-flow oxygen is used, the patient's head must be positioned allowing an open airway (jaw thrust), and oxygen up to 60 liters per minute, not less than 15 liters, must be provided. After laryngoscopy, it is necessary

opening percutaneous/surgical tracheostomy without delay [30].

to avoid hyperoxia and its complications and decrease oxygen flow [9, 35].

• Inadequate circulation: cardiac arrest in hypothermic and hypotensive cases.

and laryngospasm.

62 Tracheal Intubation

gas less than 55 mmHg, PCO<sup>2</sup>

pocalcemia, brainstem infarction, etc.).

ventional radiology, endoscopic procedures.

Endotracheal intubation indications can be summarized as follows [6, 24, 28, 29, 36, 37]:

• Airway problems: external pressures on the airway, vocal cord paralysis, tumor, infection,

• Respiratory deficiencies: patients with poor general condition, hypoxemic/hypercarbic respiratory insufficiency (respiratory rate less than 8 or more than 30 per minute, PO<sup>2</sup>

• Muscle and central nervous system problems and metabolic disorders: diseases of the muscles of respiratory system and auxiliary muscle disorders allowing respiratory failure and central apnea syndromes (Guillain-Barre, amyotrophic lateral sclerosis, myasthenia gravis, muscular dystrophy, acid-maltase insufficiency, phrenic nerve injury, botulism, polymyositis, spinal cord injury, electrolyte imbalance, hypophosphatemia, hypomagnesaemia, hy-

• For the purpose of examination and transfer of patients: MRI scan under sedation, inter-

• If urgent aggressive sedation is required to protect the patient: to avoid postoperative intracranial pressure increase, to provide cerebral protection with controlled hypotension and

above 55 mmHg, and non-compensated acidosis-alkalosis).

in blood


In urgent conditions, nasal, oral, awake, fiber optic, and rigid intubation and, if necessary, intubation through the laryngeal tube can be technically applied, and the choice of method is decided according to the patient's clinic.

When endotracheal intubation is performed under emergency conditions, it may be beneficial to consider the following conditions:

**a.** Equipment: intravenous (IV) catheter, laryngoscope, and blade, endotracheal tube in appropriate size, injector to inflate cuff, Magill forceps, nasal/oral airway, aspiration catheter, tube changer, guide wire, nasogastric tube, tube fixation.

important point to consider is that if sufficient mask ventilation is provided, muscle relaxants can be given. Preoxygenation applied to patients gains time for intubation. Patients with a high-risk group (coronary artery disease, cerebral aneurysm) may be given additional pharmacological agents to provide hemodynamic stability. Different techniques, equipment, and agents can be used. Insertion of endotracheal tube into the trachea is essential. Anesthetic

Indications for Endotracheal Intubation http://dx.doi.org/10.5772/intechopen.76172 65

Generally, Macintosh and Miller blades are used for a direct laryngoscopy. The Macintosh blade is inserted into the gap called vallecula between the tongue base and the pharyngeal surface of the epiglottis. It provides a good passage for minimal epiglottic trauma and endotracheal tube. Miller blade extends to the laryngeal surface area of the epiglottis, making it easier to open the glottis but narrowing the oropharyngeal angle of view. There should be a certain distance between the operator's eye and the patient's airway. A close look at the patient will narrow the angle of vision. The laryngoscope's blade is moved from left to right in the airway by providing adequate mouth opening without damaging the lips and tongue. The blade should never be leaning on the upper jaw and upper incisors, and intubation should not be done by leaning on there. Pressing out of

The endotracheal intubation tube is held in the right hand and moved from the right of the patient's mouth toward the vocal cords. If there is a problem of routing the tube, it may be possible to orient the tube anteriorly using a probe. The cuff of the endotracheal tube is fixed

Adequate time and equipment often may not be available for endotracheal intubation. In some cases, it may be decided to intubate very quickly. For example, in various clinical situations that threaten the patient's life, time loss is more dangerous than the risks associated with rapid sequence intubation. In general, rapid sequence intubation is applied in situations indicated

• Loss of consciousness and concomitant vomiting, increased secretion, or risk of blood

agents are not needed in patients under GCS 4 and with cardiac arrest [18, 25].

the cricoid cartilage is beneficial for better visualization of the glottis gap [4, 28].

after passing the vocal cords and is inflated with an air of 3–4 mL.

**a.** The presence of all kinds of obstacles blocking the airway:

• Upper respiratory tract edema, as in anaphylaxis or infection

• Obesity, short neck, short jaw, airway deformity

**b.** Loss of consciousness and airway reflex:

• Failure to protect airway against aspiration

• Face or neck trauma with oropharyngeal bleeding or hematoma

**3.1. Rapid sequence intubation (RSI) indications**

below [15, 38]:

aspiration


Comparison of intubation performed under emergency conditions and intubation performed under elective conditions.


Cases where the NIV is contraindicated (coma, postoperative agitation, delirium, noncooperative patients, patients with gastric distention risk) may be in the semi-urgent or urgent category [31, 32]. It is decided according to the deterioration of the clinical course of the patient whose blood gas is followed and having spontaneous respiration.
