The Core of Anesthesia: Understanding the Breathing Tube
When a patient undergoes general anesthesia, their body enters a state of controlled unconsciousness where muscles, including the diaphragm which controls breathing, become paralyzed [1.2.4, 1.6.6]. This necessitates assistance to ensure the patient continues to breathe safely and effectively throughout the procedure [1.2.5]. The answer to the question, 'Why do they put a tube in your throat when you have surgery?' lies in this fundamental need for airway management. This tube, called an endotracheal tube (ETT), is a flexible plastic tube inserted through the mouth or nose into the windpipe (trachea) [1.2.3]. It serves as a secure and direct channel to the lungs, playing several vital roles in patient safety [1.2.5].
Primary Functions of an Endotracheal Tube
The use of an endotracheal tube is a standard of care in many surgeries for several key reasons:
Maintaining a Patent Airway
Under anesthesia, the muscles in the throat can relax and cause the airway to collapse or become obstructed [1.2.5]. The ETT physically holds the airway open, ensuring a continuous and unobstructed path for air to travel to and from the lungs [1.2.3]. This is known as maintaining airway patency.
Delivering Oxygen and Anesthetic Gases
General anesthesia is often maintained with a mixture of oxygen and anesthetic gases [1.2.6]. The ETT provides a closed, sealed system for the efficient and controlled delivery of these gases directly into the lungs [1.2.1, 1.2.5]. An inflatable cuff near the end of the tube creates a seal against the tracheal walls, preventing gas from leaking out and ensuring the precise amount of anesthetic is administered [1.3.2].
Mechanical Ventilation
Since general anesthesia paralyzes the muscles required for breathing, a machine called a ventilator is used to breathe for the patient [1.2.4]. The ETT serves as the crucial connection point between the patient and the ventilator, which pushes air and oxygen into the lungs and allows carbon dioxide to be exhaled [1.2.3].
Protection Against Aspiration
One of the most critical functions of the ETT is to protect the lungs from aspiration, which is when foreign substances like stomach contents, blood, or oral secretions are inhaled [1.2.3, 1.2.6]. The inflated cuff on the tube seals the airway, preventing any fluids from passing into the lungs, which could otherwise lead to serious complications like pneumonia [1.3.3, 1.4.6]. This protection is especially important in emergency surgeries or for patients with a full stomach [1.7.3].
The Intubation and Extubation Process
Intubation is performed by an anesthesiologist after the patient is fully unconscious from initial intravenous anesthetic medications [1.2.6]. A tool called a laryngoscope is used to gently move the tongue and visualize the vocal cords, allowing the provider to guide the ETT into the trachea [1.3.3]. Once in place, the cuff is inflated and placement is confirmed by listening for breath sounds and checking for carbon dioxide during exhalation [1.3.5]. The entire process is usually completed in less than a minute [1.3.6]. The patient has no memory of the event [1.7.3].
The removal of the tube, known as extubation, occurs as the surgery concludes and the patient begins to awaken [1.2.6]. The anesthesia care team ensures the patient can breathe adequately on their own before deflating the cuff and gently removing the tube [1.3.5, 1.8.2].
Comparison of Airway Devices
Not all general anesthesia requires an endotracheal tube. For some shorter, less complex procedures, a supraglottic airway (SGA), such as a Laryngeal Mask Airway (LMA), may be used [1.2.5]. An LMA sits above the vocal cords rather than passing through them [1.2.5].
| Feature | Endotracheal Tube (ETT) | Laryngeal Mask Airway (LMA) |
|---|---|---|
| Placement | Passes through the vocal cords into the trachea [1.2.5]. | Sits in the back of the throat, above the vocal cords [1.2.5]. |
| Invasiveness | More invasive, requires a laryngoscope for placement [1.2.5]. | Less invasive, often placed without a laryngoscope [1.2.5]. |
| Aspiration Protection | Provides superior protection due to the cuffed seal inside the trachea [1.5.2]. | Less protection against aspiration; not ideal for patients with a full stomach or reflux [1.2.5]. |
| Common Side Effects | Higher incidence of sore throat, hoarseness, and postoperative cough [1.4.5, 1.5.6]. | Lower incidence of sore throat and cough [1.5.1, 1.5.3]. |
| Typical Use Cases | Longer surgeries, abdominal or chest surgery, laparoscopic procedures, and patients at risk of aspiration [1.2.5, 1.7.4]. | Shorter procedures where the patient can breathe spontaneously and has a low risk of aspiration [1.2.5, 1.7.3]. |
Risks and Post-Operative Expectations
The most common side effect of intubation is a sore throat, which affects a large percentage of patients and typically resolves within a few days [1.2.4, 1.6.2]. Hoarseness is also common but usually temporary [1.2.4]. These symptoms are caused by irritation to the delicate tissues of the throat and vocal cords from the tube itself [1.6.6]. Drinking plenty of fluids, using throat lozenges, and limiting talking can help manage this discomfort [1.6.6].
While serious complications from endotracheal intubation are rare, they can include damage to teeth, the larynx, or trachea, and infection [1.2.1, 1.4.2]. The risk of complications increases with the duration of intubation [1.4.3].
Conclusion
The use of a breathing tube during surgery is a cornerstone of modern anesthesia, providing a multifaceted approach to patient safety. By securing the airway, enabling mechanical ventilation, delivering anesthetic agents, and protecting the lungs from aspiration, the endotracheal tube allows surgeons to perform complex procedures while the patient remains safely unconscious and physiologically stable. While the prospect can be daunting, it is a routine and life-saving procedure performed millions of time by highly skilled professionals.
For more information from an authoritative source, you can visit the American Society of Anesthesiologists' patient resources.
