Intubation is a medical procedure involving the placement of a flexible plastic tube, known as an endotracheal tube, into the trachea to secure an open airway. The tube is usually inserted through the mouth, past the vocal cords, and directly into the lungs. This intervention ensures the patient receives oxygen and that carbon dioxide is effectively removed from the body. It is a time-sensitive, life-saving measure frequently performed in emergency rooms, intensive care units, and operating theaters during general anesthesia. The goal is to temporarily replace the body’s natural breathing mechanism when it has failed or is compromised.
Why Airway Management is Necessary
Intubation is required when a person’s natural ability to maintain a clear airway or breathe adequately is lost. One reason is respiratory failure, where the lungs cannot effectively exchange gases, failing to bring in enough oxygen or remove enough carbon dioxide. This failure often results from conditions that weaken respiratory muscles or severely damage lung tissue, leading to dangerously low oxygen levels and high carbon dioxide levels in the blood. Securing the airway ensures the patient’s cells receive the oxygen they need while medical staff treat the underlying condition.
Another major indication is the inability to protect the airway. If a person has a severely reduced level of consciousness, such as from trauma or a drug overdose, protective reflexes like coughing and gagging can disappear. Placing the endotracheal tube allows a small balloon cuff to be inflated, which seals the trachea and prevents foreign material, like stomach contents, from entering the lower airways. This complication is known as aspiration.
Intubation is also necessary during major surgeries requiring general anesthesia. The medications used to induce deep sleep often suppress the body’s urge to breathe and cause muscle relaxation. The tube allows the anesthesiologist to take complete control of the patient’s breathing throughout the operation.
The Intubation Procedure From the Patient’s View
The intubation procedure is performed while the patient is completely unconscious to ensure comfort and safety. Before placement, the medical team prepares the patient by positioning the head and neck to create the straightest path possible from the mouth to the trachea. The patient is first given a combination of powerful medications, typically starting with a potent sedative and a strong pain reliever.
Once the patient is deeply sedated, a neuromuscular blocking agent, or paralytic, is administered to temporarily relax the muscles, including the vocal cords and jaw. This combination, often called rapid sequence intubation, ensures the patient is unaware of the process and unable to resist the tube placement. Because the patient is unable to breathe on their own after paralysis, the procedure must be executed quickly and precisely.
The healthcare provider uses a tool called a laryngoscope, which has a light and a blade, to gently move the tongue out of the way and gain a direct view of the vocal cords. The tube is then threaded through the vocal cords and into the trachea, a process that usually takes less than a minute. Once the tube is in place, the balloon cuff is inflated to seal the airway, and the tube is connected to a mechanical ventilator.
The provider confirms the tube’s correct position by listening to the lungs for breath sounds and using a device that measures carbon dioxide in the exhaled air. The tube is then securely taped or fastened to the face to prevent accidental movement. Due to the heavy sedation and paralysis, patients have no memory of the insertion itself.
Life While Receiving Mechanical Ventilation
Once the endotracheal tube is secured, the patient is connected to a mechanical ventilator, a machine that takes over the work of breathing. The ventilator delivers positive pressure breaths, pushing air into the lungs, which is the opposite of the natural negative pressure mechanism of spontaneous breathing. The machine can be set to deliver a specific volume of air with each breath (Volume-Controlled Ventilation) or a set pressure (Pressure-Controlled Ventilation).
The patient remains in an intensive care setting and is continuously monitored. Sedation is maintained to keep the patient comfortable and to reduce the risk of complications like delirium and prolonged time on the ventilator. Modern critical care often aims for a light level of sedation, allowing the patient to be minimally responsive.
Since the tube bypasses the body’s natural coughing mechanism, the patient cannot clear secretions. The care team must perform suctioning, which involves inserting a small catheter down the tube to remove mucus and fluid as needed. This is often indicated by audible secretions or changes in the pressures displayed on the ventilator monitor.
Because the tube passes through the vocal cords, the patient is unable to speak. Nurses and staff utilize non-verbal methods, such as whiteboards, letter boards, or hand gestures, to help the patient communicate. Temporary physical restraints may be necessary in some instances to prevent the patient from accidentally pulling out the endotracheal tube.
Weaning the Patient and Recovery
The process of taking the patient off mechanical support is called weaning. It begins when the underlying medical issue has improved and the patient meets specific criteria. Readiness is assessed daily by ensuring the patient:
- Is hemodynamically stable.
- Requires minimal ventilator support.
- Has a low oxygen requirement.
- Has met physiological goals.
Once these physiological goals are met, the patient undergoes a Spontaneous Breathing Trial (SBT). During the SBT, ventilator settings are reduced to provide only minimal pressure support. This requires the patient to perform most of the work of breathing on their own for a set period.
A successful trial indicates the patient’s respiratory muscles are strong enough and their breathing pattern is stable, signaling readiness for extubation, which is the removal of the tube. Extubation is a swift procedure where the cuff is deflated and the tube is pulled out in one smooth motion, often resulting in a brief, strong cough. Immediate after-effects include a sore throat, hoarseness, and chest discomfort due to the presence of the plastic tube against the delicate tissues of the airway.
A concern following extubation is dysphagia, or difficulty swallowing. The tube can cause temporary injury or swelling to the vocal cords and throat muscles necessary for safe swallowing. This impairment elevates the risk of aspiration. For this reason, patients are often evaluated by speech therapists before being allowed to eat or drink.