Ventilation via a Tracheal Tube
Intubation enables the airway to be secured within seconds. It is an established technique in emergency and intensive care medicine and saves patients’ lives every day.
Various types of tube are available for ventilation via a tracheal tube – each with their own advantages and disadvantages. Find out more about the diverse range of options and their deployment scenarios here.
Definition: What does ventilation via a tracheal tube refer to?
Ventilation via a tracheal tube is considered invasive ventilation and is distinguished from non-invasive ventilation via a mask. It is a method of artificial ventilation in which a tracheal tube is used to secure the airway. This usually involves a tracheal tube that is inserted into the windpipe (trachea).
Alternatively, supra- or extraglottic auxiliary equipment such as a laryngeal tube or laryngeal mask can also be used. Placement of the tracheal tube takes place under anesthesia and is known as intubation. Whenever it can be expected that a patient will have to be ventilated for longer than 10 to 14 days, a tracheotomy is indicated. This involves surgically creating direct access to the trachea.1
Spheres of application
Invasive ventilation via a tracheal tube is used in patients with respiratory insufficiency, cardiovascular arrest or injuries to the lungs and trachea. Intubation is also necessary in the case of serious facial swelling or injuries that encumber mask ventilation.
As a rule, ventilation via a tracheal tube is chosen for ventilation under general anesthesia, as sedation severely impairs respiratory function. Additionally, a tracheal tube is used in comatose patients.
Furthermore, it is used to secure the airway against obstruction – for example in the event of unconsciousness. Moreover, a tracheal tube during ventilation protects against aspiration. Above and beyond this, intubation is also effective to suction off bronchial secretions and support the success of therapy.2
Advantages of ventilation via an endotracheal tube
Ventilation via an endotracheal tube offers several advantages. Known as the gold standard, it provides a reliable way securing of the airway. Video laryngoscopy offers additional help under difficult intubation conditions.
The use of tube systems with an inflatable cuff protects patients from aspiration. In addition, sealing off the trachea with the cuff enables the application of higher ventilation pressures as compared to the use of extra- or supraglottic airway auxiliary equipment. Furthermore, this also results in fewer leaks.
What are the risks of ventilation via an endotracheal tube?
As an invasive procedure, ventilation via an endotracheal tube is also associated with risks. It requires much training and can cause the following complications under certain circumstances:
- Cyanosis, tachycardia, drop in blood pressure and in O₂ saturation
- Damage to teeth
- Jaw dislocation, laryngospasm and restricted mouth opening³
- Injuries to the laryngeal region (laryngotrauma)
- Perforation
- Mucosal injuries and bleeds⁴
- Aspiration
- Incorrect intubation⁵
Incorrect intubation and checking tube position
A potentially life-threatening complication during ventilation via a tracheal tube is incorrect intubation into the esophagus. If diagnosed too late, this leads to serious hypoxia that can result in irreversible brain damage or death of the patient. Studies show that over 15 % of cardiac arrests during intubation are caused by intubation of the esophagus.6
If incorrect intubation is suspected or diagnosed, ventilation must be stopped immediately to avoid gastric insufflation or rupture of the stomach. The tracheal tube should be removed immediately and reinserted after temporary ventilation.
It is essential that the tube position is monitored to recognize and correct any incorrect intubation at an early stage. Signs of intubation into the esophagus include, among others:
- Inflation of the stomach during ventilation,
- gurgling noises on auscultation of the stomach region,
- increasing cyanosis and
- lack of CO₂ exhalation⁶
During ventilation, a correct position of the tracheal tube is indicated by a slight, synchronous rise of the ribcage and regular breathing noises on both sides. Ventilation should be possible without a great expenditure of pressure. A unilateral breath indicates a potential misplacement of the tracheal tube – for example due to a feed in one of the main bronchi. After checking the tube position, the end of the tracheal tube should be carefully secured to prevent it from slipping out of place.4
Types of intubation
Intubation is performed differently depending on the type of airway auxiliary equipment used.
Endotracheal intubation
During endotracheal intubation, the patient is initially preoxygenated with pure oxygen for 3–5 minutes. Afterwards, the head is hyperextended to facilitate access through the mouth and pharynx. The laryngoscope, a metal blade equipped with an integrated light source, is used to depress the tongue and expose the larynx.
Afterwards, the tracheal tube is inserted through the rima glottidis into the trachea, usually under anesthesia, and the other end of the tube connected to a ventilator or bag-valve mask. Once located in the upper portion of the trachea or in the middle of the trachea, the cuff is inflated. In this way, the trachea is sealed off.
This form of ventilation via a tracheal tube is ideally suited for a duration of ventilation that is limited to a few days. However, it is not suitable for situations with difficult intubation conditions.7
Application of laryngeal tube, laryngeal mask and i-gel
The laryngeal tube, laryngeal mask and i-gel laryngeal mask are alternatives to ventilation via a tracheal tube and are used under difficult intubation conditions – for example, if it is not possible to hyperextend the patient’s head or if an initial attempt with the tracheal tube has failed. These devices can usually be inserted blindly and in just a few seconds.
The airway aids are not inserted through the larynx, but only up to the laryngeal inlet by advancing them along the hard palate up into the region of the esophageal ostium (hypopharynx). After placement, the cuffs on the laryngeal mask and tracheal tube are inflated to seal off the laryngeal inlet and block the esophagus.8
One challenge of these airway devices is the potential lack of leaktightness, which can lead to leaks. Such leaks could possibly lead to gastric insufflation. There is also a risk of aspiration if the laryngeal inlet is not sealed off adequately.
Video laryngoscopy
Video laryngoscopy improves visualization of the airway during intubation. In contrast to conventional laryngoscopy, it enables an indirect view onto the larynx through a laryngoscope with an integrated camera.
This is particularly advantageous under difficult intubation conditions like those in patients with restricted mouth opening or anatomical anomalies because the method provides a clearer view onto the vocal cords. The success rate of video laryngoscopy is 85.1 % compared to 70.8 % for direct laryngoscopy.9
Intubation via the nose
Nasotracheal intubation is a suitable method if the duration of ventilation is expected to exceed 5–7 days. A tracheal tube to which lubricant has previously been applied is passed through a nostril into the pharynx and then advanced into the trachea using forceps.
Fiberoptic intubation
Fiberoptic intubation is a technique used under difficult intubation conditions. It can be performed orally and nasally, whereby the nasal method is preferred if the intubation is planned.
After administering an anesthetic nasal spray, the doctor inserts the bronchoscope through a nostril. As soon as the trachea is reached, the patient is anesthetized and the ventilation tube is advanced along the endoscope into the trachea. This method is not recommended in emergency situations – especially if visibility is impaired.
Weaning and extubation
After clinical improvement, the patient is extubated. The prerequisite is that the patient has been sufficiently weaned off the ventilator. Extubation criteria include stable gas exchange, stable respiratory mechanics, the presence of spontaneous breathing as well as an intact swallowing and cough reflex.
Prior to extubation, it is important to prepare the patient mentally and raise their upper body to at least 30°. Beforehand, their existing nutrition should be paused for 2 to 4 hours to reduce the risk of aspiration. The suctioning off of secretions from the stomach tube and pharyngeal cavity should not be forgotten either.
The use of WEINMANN ventilators with various airway aids
The WEINMANN MEDUMAT Standard² and MEDUVENT Standard ventilators are suitable for use during both invasive and non-invasive ventilation and can be combined with a variety of airway aids. This enables medical professionals to react quickly and safely to the respective needs of the patients, whether ventilation is being administered via a tracheal tube or by using airway devices. This renders the devices indispensable tools in emergency and intensive care medicine.
For example, the RSI mode on the MEDUMAT Standard² is custom-tailored to the requirements of emergency anesthesia and intubation. The MEDUtrigger, which is attached to the mask and connected to the ventilator via an electrical cable, is available for the MEDUVENT Standard.
Both devices feature intuitive operation, various ventilation modes, comprehensive parameter monitoring functions as well as both acoustic and visual warning signals that maximize patient safety. Thus, the MEDUMAT Standard² and the MEDUVENT Standard are ideally suited for use in a broad variety of emergency situations.
1 Lang, Hartmut (2017): Außerklinische Beatmung. Edition Berlin Heidelberg: Springer Verlag, p. 72.
2 Larsen, R. & Mathes, A. (2023): Beatmung. 7th Edition Berlin Heidelberg: Springer Verlag, p. 131
3 Larsen, R. & Mathes, A. (2023): Beatmung. 7th Edition Berlin Heidelberg: Springer Verlag, p. 141
4 https://www.netdoktor.de/therapien/intubation/
5 Lang, H. (2020): Beatmung für Einsteiger. Theorie und Praxis für die Gesundheits- und Krankenpflege, 3rd Edition Berlin Heidelberg: Springer Verlag, p. 39.
6 Larsen, R. & Mathes, A. (2023): Beatmung. 7th Edition Berlin Heidelberg: Springer Verlag, p. 156.
7 Larsen, R. & Mathes, A. (2023): Beatmung. 7th Edition Berlin Heidelberg: Springer Verlag, p. 145ff.