Patient Info

Airway Information for Patients
(Version 1.5, March 9, 2010)

What is Clinical Airway Management?

Anesthetic agents and drugs used for pain and sedation often “turn off” or depress parts of the nervous system. As a result,they often alter normal breathing so that many patients snore or may not breathe properly without airway support and supplemental oxygen. In addition, for certain surgical procedures, drugs that paralyze muscles are given in order to permit the surgeon to work, and this also stops normal breathing. Anesthesia caregivers become experts in airway management because of these side effects of anesthesia care for surgery or for procedural sedation.

In a nut shell, clinical airway management is concerned with keeping you, as a patient, breathing effectively during these times. The anesthesia care giver concentrates either on your breathing spontaneously, as you are now and when you normally sleep at night (spontaneous breathing), or on your breathing with the assistance of a mechanical device like a ventilator that does the breathing for you (positive pressure ventilation). In either case airway management has three major goals [1] keeping arterial blood oxygen levels in a safe range, [2] keeping arterial blood
carbon dioxide levels in a safe range, and [3] preventing lung injury that may result from causes
such as stomach acid spilling into the lungs (aspiration pneumonitis), secretion retention that may lead to pneumonia, or partial lung collapse during surgery (atelectasis).

In some cases, airway management requires placement of an artificial airway that holds the tissues of the mouth open during breathing. In many other cases this involves placement of a disposable breathing tube through the mouth or the nose into the windpipe (endotracheal tube) with the aid of an instrument called a laryngoscope. This process is called “endotracheal intubation” or, simply,”intubation”.

The most common setting where intubation is employed is in the Operating Room, but other common clinical settings where airway management and intubation is required include Emergency Departments and Intensive Care Units. Patients who are very ill or who can not breathe because of illnesses that cripple lung function or cause loss of normal consciousness, sometimes need ventilatory support in these special care settings. For this reason, many intensive care, pulmonary and emergency doctors also need to learn airway management skills. For emergencies that arise outside of the hospital, many paramedics are trained in intubation.

What happens in the Operating Room?

Once you are brought into the Operating Room for surgery, an intravenous (IV) is started and a number of monitors are attached. In major cases, special monitors, such as monitoring catheters (plastic tubes) going into the heart or into the artery for blood pressure measurement or fluid infusion, may be used. For your safety, more than one IV catheter is often placed when a large loss of blood or fluid requirement is possible. After the anesthesia care giver has checked his or her anesthesia machine and surveyed the environment in which he or she is working to ensure everything is in place, the patient is given oxygen by face mask and a number of drugs are given to start general anesthesia. Typically, this will involve a drug (“hypnotic”) such as thiopental or propofol that causes the patient to go rapidly to sleep and “induce” general anesthesia. One of these drugs may be followed by a “muscle relaxant” to loosen up all the patient’s muscles, when needed. In fact, with muscle relaxation, the patient is paralyzed and completely unable to move. This, of course, would be a horrible experience if one was awake, but it is done after drugs have rendered the patient unconscious. The reason the muscle relaxant is given is that it may be required for surgery and it also makes it easier to put in the endotracheal tube. As noted above, an endotracheal tube is usually placed using a metal, battery powered instrument called a laryngoscope. The laryngoscope is essentially a lighted tongue blade that holds a patient’s mouth open and shines light on the larynx, or voice box, for examination or to direct passage of the endotracheal tube. Later on, muscle relaxation may be needed to facilitate the surgeon’s work.

With the introduction of the endotracheal tube, the patient is then usually attached to a ventilator (breathing machine) which is set to breathe for him or her during surgery. Very often, additional medications to keep you asleep are introduced as gaseous mixtures that you breathe through the endotracheal tube. These include nitrous oxide (commonly called “laughing gas”), typically in a concentration range of 60% to 70%, accompanied by oxygen, and a “potent inhalational anesthetic agent” such as isoflurane, sevoflurane, or desflurane. This is called the “maintenance” phase of the anesthetic. Not infrequently, inhalational agents are used in conjunction with opiate pain medicines such as fentanyl or morphine to keep postoperative pain to a minimum and reduce the amounts of inhalational agent required so that patients can awaken more quickly after anesthesia and surgery. The anesthesia care giver continually monitors the concentrations and clinical effects of anesthesia during the procedure and adds more drugs as required to keep the appropriate level of anesthesia and provide good operating conditions for the surgeon.

Is everyone intubated?
What if they can’t get the breathing tube in?

As noted earlier, for many surgical procedures a breathing tube, known as the endotracheal tube, is introduced using a laryngoscope instrument. This tube is passed between the vocal cords into the windpipe (trachea) and is sealed into position using a special balloon around the tube, or cuff, inflated with air. Ordinarily, there is little difficulty in inserting the tube once anesthesia has begun. However, from time to time, it may be surprisingly difficult to insert a breathing tube. We call this “difficult intubation”.

If your anesthesia care giver encounters this problem, which occurs about one in every hundred or so cases, he or she has a protocol or “algorithm” guide to deal with this problem. In some cases, this recommendation may involve using an alternative form of airway management or may involve waking the patient up and doing the procedure under regional anesthesia (e.g. epidural or spinal). The particular approach taken in this rather unusual circumstance will depend on the training or preferences of your anesthesia care giver. Incidentally, if your anesthesiologist tells you after the surgery that he did have trouble putting in a tube even though he was successful, it is wise to get all the details from him or her in a letter or other document so that you will have this information at hand for other anesthesia care givers who you encounter in the future. In fact, the Medic-Alert Foundation has a difficult airway record system available to keep this kind of information sorted out.

Will I have a sore throat after intubation?

Not infrequently, the insertion of the endotracheal tube can result in a sore throat. This is not often so severe as to be a major problem, but some people find it annoying indeed. Note, however, that a sore throat can occur even if intubation is not carried out, for example, after use of an alternative airway management technique such as the so-called “laryngeal mask airway” or after breathing dry anesthesia gasses for a while. Occasionally, people use throat lozenges or gargle salt water to deal with this problem, but most of the time, when it does occur, it is too minor to be particularly troublesome.

I have a loose tooth. Is that a problem?

Your anesthesia care giver will want to know about any loose teeth or capped teeth or dentures or bridges or crowns. This is because when the laryngoscope is introduced to allow the insertion of the endotracheal tube, the teeth are very close by and there is always a possibility of a tooth being chipped or damaged, particularly if a tooth is capped or if a tooth is loose. By giving any details of any loose or capped teeth etc. to your anesthesia care giver, he or she can make a particular effort to avoid exacerbating the problem. Sometimes, if a tooth is really loose, it is wise just to take it out before starting the anesthetic to avoid the possibility that the tooth may be dislodged and end up in your lungs.

I am a smoker. Is this a special problem?

No question about it, smokers are more of a problem than non-smokers from an airway point of view. Smokers are more likely to undergo airway-related complications such as “bronchospasm” or “laryngospasm” after the induction of the anesthetic or after the breathing tube is pulled out, but fortunately, these are not as common as they could be and usually we deal with these problems without excessive difficulty. Nevertheless, most clinicians would not like to have to deal with these problems at all. If you are a smoker, our advice is to quit smoking as soon as you can. This is sometimes impractical advice in that the period before surgery is potentially very stressful for the patient. But even if you can quit smoking for only 48 hours before the surgery, this alone will help reduce the degree of carboxyhemoglobin in your blood and allow more oxygen to be transported in your body. Smokers must also be especially careful to carry out deep breathing exercises after their surgery to prevent collapse of their lungs and/or pneumonia. The use of a so-called incentive spirometer can be very helpful in this regard.