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**Chapter 3**

**Provisional chapter**

**Indications for Endotracheal Intubation**

**Indications for Endotracheal Intubation**

DOI: 10.5772/intechopen.76172

Endotracheal intubation may be required when respiratory distress or airway integrity cannot be achieved or maintained for any reason. It should be considered that intubation may be required when evaluating the patient, and that in the long term, airway protection will be needed or that the problem cannot be solved by noninvasive ventilation via airway aids and devices. Identifying the problem causing the patient's respiratory failure helps in making the decision to intubate. In fact, the clinician must be fast and self-confident when deciding on intubation. It is difficult to decide in some complex situations. It is very important to evaluate the patient, according to clinical status, age, and comorbidity, and to determine urgent intubation need. In non-diagnostic cases, further research is needed to investigate the causes of the condition such as hypoxia/ hypercapnia resulting in patient respiratory distress. Different voice tone, swallowing difficulties, coughing attacks, stridor, dyspnea can be a sign of upper airway obstruction. Arterial blood gas analysis will facilitate our decision to make intubation. Noninvasive pulse oximetry and continuous capnography values may also be a guide, but the most important thing is that delayed intubation decision may bring life-threatening

**Keywords:** intubation, endotracheal, indications, airway problems, rapid sequence

Endotracheal intubation is the placement of a tube into the trachea, either orally or nasally for airway management. Endotracheal tube forms an open passage in the upper airways. To be able to ventilate the lungs, the air must be free to enter and exit the lungs. The patient is connected to the mechanical ventilator to provide continuous respiration with an endotracheal

> © 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

distribution, and reproduction in any medium, provided the original work is properly cited.

Additional information is available at the end of the chapter

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.76172

Yeliz Şahiner

**Abstract**

situations.

**1. Introduction**

intubation, nasotracheal intubation

Yeliz Şahiner

#### **Indications for Endotracheal Intubation Indications for Endotracheal Intubation**

#### Yeliz Şahiner Yeliz Şahiner

Additional information is available at the end of the chapter Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.76172

#### **Abstract**

Endotracheal intubation may be required when respiratory distress or airway integrity cannot be achieved or maintained for any reason. It should be considered that intubation may be required when evaluating the patient, and that in the long term, airway protection will be needed or that the problem cannot be solved by noninvasive ventilation via airway aids and devices. Identifying the problem causing the patient's respiratory failure helps in making the decision to intubate. In fact, the clinician must be fast and self-confident when deciding on intubation. It is difficult to decide in some complex situations. It is very important to evaluate the patient, according to clinical status, age, and comorbidity, and to determine urgent intubation need. In non-diagnostic cases, further research is needed to investigate the causes of the condition such as hypoxia/ hypercapnia resulting in patient respiratory distress. Different voice tone, swallowing difficulties, coughing attacks, stridor, dyspnea can be a sign of upper airway obstruction. Arterial blood gas analysis will facilitate our decision to make intubation. Noninvasive pulse oximetry and continuous capnography values may also be a guide, but the most important thing is that delayed intubation decision may bring life-threatening situations.

DOI: 10.5772/intechopen.76172

**Keywords:** intubation, endotracheal, indications, airway problems, rapid sequence intubation, nasotracheal intubation

#### **1. Introduction**

Endotracheal intubation is the placement of a tube into the trachea, either orally or nasally for airway management. Endotracheal tube forms an open passage in the upper airways. To be able to ventilate the lungs, the air must be free to enter and exit the lungs. The patient is connected to the mechanical ventilator to provide continuous respiration with an endotracheal

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

tube. The utilized tube is a flexible plastic tube which is called endotracheal tube placed on the trachea and has a cuff part that can be inflated with air to prevent airway leakage. To facilitate the placement of the endotracheal tube, general anesthesia induction is applied to patients who will be operated and have sufficient fasting time. In emergency cases, endotracheal intubation is performed with various stages and procedures. Sometimes, patients are intubated at the scene or in the emergency room of the hospital. Because the patients' clinical status cannot be fully evaluated during the intubation procedure at the scene, sometimes drugs cannot be given [1, 2]. Deep sedation, rapid sequence intubation (RSI), is performed according to the patient's clinical condition in the hospital and also in patients with Glasgow coma scale (GCS) 4, and, below, the procedures are done without medication. Intubation without medication to trauma patients with high GCS (above 4) is not safe, resulting in intracranial pressure increase, vomiting, esophageal intubation, and aspiration risk. Special procedures are required in pediatric patients and newborns, and their indications for endotracheal intubation can show variability.

whether it will be reversible in the long term [17, 18]. Before the patient is intubated or until the intubation decision is made, mask ventilation is made, or high-flow nasal oxygen is used [19, 20]. High-flow oxygen therapy helps in difficult airway conditions such as in obesity or in the dif-

Indications for Endotracheal Intubation http://dx.doi.org/10.5772/intechopen.76172 61

The fact that the procedure to be performed after the endotracheal intubation decision is invasive, requiring multiple medications and not waking up of the patient due to the sedatives for hours and hypotension risk are the disadvantages of endotracheal intubation [23]. In the opposite case, the patient's clinical condition that can worsen is unpredictable. If tardy for endotracheal intubation, hypercapnia, hypoxia, acidosis, and arrest as a result of circulation collapse in cases where it cannot be compensated take place. For this reason, the patient's clinic, existing diseases, laboratory tests, and blood gas results should be evaluated together, resulting in a better decision. Although evaluation is not possible in case of emergency, the simple imaging methods and ultrasonography can help physicians. In conscious patients with spontaneous breathing and hypoxia without hypercarbia in room air, improvement of saturation after oxygen treatment with 2–4 L/min nasal/mask and reaching a normal value of spontaneous respiration after noninvasive ventilation treatment of 1–2 hours may be the clinical signs that the patient will benefit from noninvasive ventilation. Patients requiring intubation have at least one of the fol-

**I.** Inability to keep airway open (dislocation of the tongue toward the pharynx, obstruction

**II.** Failure to protect airway from aspiration (oral and nasal bleeding in trauma patients,

**III.** Ventilation failure (abnormalities in airway anatomy: short neck, wide mandible, the upper jaw being in front, mandible being behind, small mouth, obesity) and difficult mask

**IV.** Insufficiency in oxygenation (cyanosis, insufficiency of chest wall movements, presence of obstruction findings in lower respiratory tracts in auscultation, gradual decrease of

**V.** Possible conditions that may lead to respiratory failure (hemodynamic changes as a result of progressive hypoxemia and hypercarbia such as tachycardia-hypertension-arrhythmia).

Tracheal intubation is generally used in patients unconscious or with respiratory failure to keep the airway open and to ensure ventilation of the patient. Endotracheal intubation is also performed in cases where general anesthesia will be applied for the operation. Endotracheal intubation is performed in various situations such as failure of noninvasive ventilation in

Acute respiratory failure is one of the most common events in the intensive care unit [26]. Airway management in intensive care unit is often more problematic than in operating theater. In general, the lack of physiological reserves is observed after induction of anesthesia during airway intervention, and some complications are seen after intubation. The person

of the upper respiratory tract, obstructive sleep apnea, burns).

secretion, fullness of stomach, gastroesophageal reflux).

ventilation may be accompanied with difficult intubation.

saturation, inadequacy of spirometric and expiratory measurements).

ficulty of mask ventilation [21, 22].

lowing five indications:

intensive care patients [24, 25].

Airway management is one of the most important skills of the physician; failure to provide required airflow can cause death or sequelae of the patient, especially in emergency conditions. The control of circulation and intubation, without losing time, in cardiac and respiratory arrest, saves the patient from hypoxia, improving quality of life in the long term [3–6]. If the difficulties in patient airway management are predictable (forced airway, lack of mask ventilation), it is important to take precautions and to ensure that adequate instruments and equipment are available [7]. Studies have shown that the likelihood of the rescue of the patient's life increases if life support is initiated within the first 4–8 minutes [8]. It is known that the treatment of nasal oxygen moistened with high flow prevents hypoxia and desaturation, while intubation is performed under emergency conditions [9, 10]. Its use is becoming widespread in the intensive care unit because of its reliability, ease of use, accessibility, and reduction of complication rate [11]. Although high-flow nasal oxygen therapy is sometimes considered an alternative to intubation, it should be remembered that these patients may need noninvasive ventilation (NIV) and intubation in the long term [12]. Although hypoxemia is a component of respiratory failure, tissue hypoxia and lactic acidosis are frequently encountered as a result of ventilation and perfusion imbalance as well as gas exchange dysfunction. As a result, complex and difficult-to-treat metabolic disorders and sometimes mixed decompensated respiratory and metabolic disorders can develop, bringing the clinical situation of a patient to an irreversible state, resulting often in organ failure [13, 14].

Endotracheal intubation using rapid sequence intubation (RSI) is the cornerstone of emergency airway management. RSI is a safe method in patients with a full stomach but is not beneficial in apneic unconscious patients (GCS <4). A patient suspected of difficult respiratory tract should be approached carefully for RSI. If a difficulty is expected, an awake technique (e.g., fiber optic intubation) is recommended. Alternatively, an anesthesiologist may be called to help secure the airway of a patient having intubation difficulty. It may be beneficial to use evidence-based and scientific techniques when deciding on intubation in emergency situations, but these procedures should be a standard practice in that clinic [6, 15, 16].

It is sometimes difficult to determine the intubation decision and its indications while evaluating a patient. Clinical experience is required to identify signs of respiratory failure and determine whether it will be reversible in the long term [17, 18]. Before the patient is intubated or until the intubation decision is made, mask ventilation is made, or high-flow nasal oxygen is used [19, 20]. High-flow oxygen therapy helps in difficult airway conditions such as in obesity or in the difficulty of mask ventilation [21, 22].

tube. The utilized tube is a flexible plastic tube which is called endotracheal tube placed on the trachea and has a cuff part that can be inflated with air to prevent airway leakage. To facilitate the placement of the endotracheal tube, general anesthesia induction is applied to patients who will be operated and have sufficient fasting time. In emergency cases, endotracheal intubation is performed with various stages and procedures. Sometimes, patients are intubated at the scene or in the emergency room of the hospital. Because the patients' clinical status cannot be fully evaluated during the intubation procedure at the scene, sometimes drugs cannot be given [1, 2]. Deep sedation, rapid sequence intubation (RSI), is performed according to the patient's clinical condition in the hospital and also in patients with Glasgow coma scale (GCS) 4, and, below, the procedures are done without medication. Intubation without medication to trauma patients with high GCS (above 4) is not safe, resulting in intracranial pressure increase, vomiting, esophageal intubation, and aspiration risk. Special procedures are required in pediatric patients and newborns, and their indications for endotracheal intubation can show variability. Airway management is one of the most important skills of the physician; failure to provide required airflow can cause death or sequelae of the patient, especially in emergency conditions. The control of circulation and intubation, without losing time, in cardiac and respiratory arrest, saves the patient from hypoxia, improving quality of life in the long term [3–6]. If the difficulties in patient airway management are predictable (forced airway, lack of mask ventilation), it is important to take precautions and to ensure that adequate instruments and equipment are available [7]. Studies have shown that the likelihood of the rescue of the patient's life increases if life support is initiated within the first 4–8 minutes [8]. It is known that the treatment of nasal oxygen moistened with high flow prevents hypoxia and desaturation, while intubation is performed under emergency conditions [9, 10]. Its use is becoming widespread in the intensive care unit because of its reliability, ease of use, accessibility, and reduction of complication rate [11]. Although high-flow nasal oxygen therapy is sometimes considered an alternative to intubation, it should be remembered that these patients may need noninvasive ventilation (NIV) and intubation in the long term [12]. Although hypoxemia is a component of respiratory failure, tissue hypoxia and lactic acidosis are frequently encountered as a result of ventilation and perfusion imbalance as well as gas exchange dysfunction. As a result, complex and difficult-to-treat metabolic disorders and sometimes mixed decompensated respiratory and metabolic disorders can develop, bringing the clinical situation of a patient to an irrevers-

Endotracheal intubation using rapid sequence intubation (RSI) is the cornerstone of emergency airway management. RSI is a safe method in patients with a full stomach but is not beneficial in apneic unconscious patients (GCS <4). A patient suspected of difficult respiratory tract should be approached carefully for RSI. If a difficulty is expected, an awake technique (e.g., fiber optic intubation) is recommended. Alternatively, an anesthesiologist may be called to help secure the airway of a patient having intubation difficulty. It may be beneficial to use evidence-based and scientific techniques when deciding on intubation in emergency situa-

It is sometimes difficult to determine the intubation decision and its indications while evaluating a patient. Clinical experience is required to identify signs of respiratory failure and determine

tions, but these procedures should be a standard practice in that clinic [6, 15, 16].

ible state, resulting often in organ failure [13, 14].

60 Tracheal Intubation

The fact that the procedure to be performed after the endotracheal intubation decision is invasive, requiring multiple medications and not waking up of the patient due to the sedatives for hours and hypotension risk are the disadvantages of endotracheal intubation [23]. In the opposite case, the patient's clinical condition that can worsen is unpredictable. If tardy for endotracheal intubation, hypercapnia, hypoxia, acidosis, and arrest as a result of circulation collapse in cases where it cannot be compensated take place. For this reason, the patient's clinic, existing diseases, laboratory tests, and blood gas results should be evaluated together, resulting in a better decision. Although evaluation is not possible in case of emergency, the simple imaging methods and ultrasonography can help physicians. In conscious patients with spontaneous breathing and hypoxia without hypercarbia in room air, improvement of saturation after oxygen treatment with 2–4 L/min nasal/mask and reaching a normal value of spontaneous respiration after noninvasive ventilation treatment of 1–2 hours may be the clinical signs that the patient will benefit from noninvasive ventilation. Patients requiring intubation have at least one of the following five indications:


Tracheal intubation is generally used in patients unconscious or with respiratory failure to keep the airway open and to ensure ventilation of the patient. Endotracheal intubation is also performed in cases where general anesthesia will be applied for the operation. Endotracheal intubation is performed in various situations such as failure of noninvasive ventilation in intensive care patients [24, 25].

Acute respiratory failure is one of the most common events in the intensive care unit [26]. Airway management in intensive care unit is often more problematic than in operating theater. In general, the lack of physiological reserves is observed after induction of anesthesia during airway intervention, and some complications are seen after intubation. The person 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 opening percutaneous/surgical tracheostomy without delay [30].

sedation in cerebral blood, to control recurrent attacks of seizures and contractions (status

Indications for Endotracheal Intubation http://dx.doi.org/10.5772/intechopen.76172 63

• In head and neck surgery: in case the airway remains in the surgical team site and the mask

• The patient positions that make it difficult to control the airway: in the positions of the face

• Thoracic and abdominal interventions: intrathoracic interventions and abdominal interventions require respiratory control and muscle relaxation. Also, interventions such as cystoscopy and hemorrhoidectomy, which may develop the reflex bradycardia, vasospasm,

• Rare cases requiring airway protection such as Stevens-Johnson syndrome and toxic epi-

In emergency conditions, equipment, technical skills, and quickness are very important when deciding on intubation indications at the bedside. Endotracheal intubation can be performed

• Patients at risk of aspiration of the stomach contents, blood, mucus, or secretion.

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

under emergency conditions in the following circumstances [6, 7, 25, 28, 29]:

• Inadequate oxygenation (hypoxia), inadequate ventilation (hypercarbia).

• Airway obstruction: variable-level obstruction in the upper and lower airways.

• The consciousness changes as far as being unable to protect airway (GCS <8).

ger. In case the treatment of patient is not successful without intubation.

• Flail chest/pulmonary contusion, in case the breathing effort puts the patient's life in dan-

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

When endotracheal intubation is performed under emergency conditions, it may be beneficial

epilepticus and tetanus).

ventilation is not possible.

dermal necrolysis.

• Apnea, respiratory failure.

• Disruption of the airway reflex.

• Cardiopulmonary resuscitation.

decided according to the patient's clinic.

to consider the following conditions:

• In case the patient is hemodynamically unstable.

**conditions**

down sit, side down, upside down, and lithotomy.

and laryngospasm through the vagal stimulation.

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

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


sedation in cerebral blood, to control recurrent attacks of seizures and contractions (status epilepticus and tetanus).

