HEAD AND NECK

Anesthesiology

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Anesthesiology in practice

The first use of the term anesthesia is attributed to the Greek philosopher Dioskouridis, in the first century BC. Later on (1871), the phrase "inhibition of the senses" is used. The current use of the term, that indicates a state of hypnosis during which it is possible to perform a surgical intervention without the patient feeling pain, is attributed to Oliver Wendel Holmes (1946). In the 20th and 21st centuries, the practical application of anesthesiology has been expanded to other areas beyond the performance of painless surgical interventions. What makes this specialty unique is the fact that it requires familiarization in other specialties, including the surgical subspecialties, general pathology, pediatrics and also clinical pharmacology, applied physiology and biomedical technology.

The role of the anesthesiologist within the surgical team

The duties of the anesthesiologist are roughly the evaluation and the preparation of the patient for the anesthesia, the alleviation of pain during surgical interventions/ operations and the evaluation, monitoring and the regaining of consciousness of the patient. The anesthesiologist must provide the best conditions in the surgical field, so that the technical part of the surgery can give the best result in the shortest period of time. Simultaneously, the anesthesiologist has to make sure that the patient is in the best overall condition during and after the operation, whether the intervention is performed with general anesthesia or under intravenous sedation.

Preoperative surgical evaluation- preparation- information

The goal of preoperative evaluation is to reduce perioperative morbidity and mortality. Thus, regardless of the seriousness of the operation, the purpose of the conversation or even meeting if necessary between the anesthesiologist and the patient is:

· To inform the patient about the anesthesia, the perioperative care, the analgesia and the recovery from the anesthesia.

· To provide the doctor with the necessary information regarding the patient's medical history (coexisting diseases and use of medicines, reported or documented allergies) and way of life (smoking, use of alcohol and /or drugs).

· To enable the anesthesiologist to decide about the necessary laboratory tests and seek the collaboration of other medical specialists.

· To enable the doctor to choose the appropriate anesthesia plan, concidering the medical history of the patient, the laboratory test results, the type and nature of the scheduled operation and the patient's desire.

· To enable the anesthesiologist to answer any question the patient may ask and provide him or her with all the relevant information.

The presence and seriousness of health problems such as diabetes, arterial high blood pressure (hypertension), chronic lung diseases (bronchitis, asthma, emphysema), thyroid disorder, kidney diseases, etc. and also the use of medicines are to be investigated. All of the above can be achieved through close collaboration between the anesthesiologist and the patient's attending physicians (cardiologist, lung specialist, endocrinologist, etc.) who know the patient's health condition in depth and can provide essential help to the preoperative preparation.

If the patient is young without a history of disease in his / her medical history (he/she does not suffer from any disorder/ disease nor does take any medicine), the purpose of the conversation with the anesthesiologist is to take away the stress a healthy person normally feels when coming into contact with a hospital environment. Preoperative laboratory tests are done (measurement of the hematocrit, the hemoglobin, the electrolytes, the blood coagulation, electrocardiogram, and a simple chest X-ray) to make sure that the patient is in excellent health. Smoking is still very popular in Greece among people of all ages. Smoking has been proven to increase the danger of postoperative complications with the respiratory system. International research on smoker patients subjected to general anesthesia has shown that smoking must be reduced to 50% at least a week before the surgical operation. Moreover, giving up smoking for at least 12 hours before the operation is extremely helpful because it minimizes the amount of carbon dioxide (gas that the smokers inhale with the nicotine) in blood thus normalizing the blood ability to carry the oxygen to the brain and the other vital organs, which is extremely important during anesthesia.

Similarly, low or moderate use of alcohol is another extremely common habit. Alcohol abuse and alcoholism are not very common phenomena, but they can overload all vital organs, particularly the liver, whose function and metabolic capacity is reduced. The reduced function of the liver is the reason why patients with a presence of medical history of alcohol abuse have a delayed recovery after receiving general anesthesia, given that most of the anesthetics are metabolized in the liver. Therefore, total abstention from alcohol during 24 hours before the operation/intervention is absolutely necessary. As previously mentioned, the type and nature of the scheduled operation require a specific study and evaluation of the patient's health condition. Therefore, before performing a serious operation such as total laryngectomy for larynx cancer treatment, further exams are carried out by a cardiologist and pulmonologist even when the patient does not have a medical history related to heart or lung.

The preoperative period is stress generating for most patients, who show fear for the operation outcome as well as about the anesthesia itself. Talking or meeting with the anesthesiologist before the operation can help the patient overcome most of his/her fears and reduce his/her stress. The patient must be informed about the exact time he/she can have medical treatment the last meal before the operation, about the duration of the operation, the preoperative plan to follow if necessary, about the medical procedure he/she will undergo such as the reason why he/she has to undergo the operation, the anesthesia plan, the postoperative analgesia plan and about the postanesthetic care he/she will receive. Providing the patient with the adequate information is of the utmost importance because a well-informed patient has less stress and collaborates better with the doctors. Lack of information increases patient stress and fear!

Types of anesthesia in ENT surgery

In the field of otolaryngology, the biggest percentage of the surgical interventions is performed only under general anesthesia. There are, however, mild surgical procedures performed under local anesthesia with parallel administration of intravenous sedation.

General anesthesia

The term general anesthesia describes a specific central nervous system condition resulting from the use of medicines called general anesthetics, which are administered through injection or inhaling. This specific condition characterized by lack of consciousness in which, in simpler words, the patient is practically sleeping, is totally controlled and reversible by the anesthesiologist. Analgesia, myochalasis and a temporary loss of reflexes are also caused. The temporary loss of reflexes as a result of the general anesthesia is of a great importance for the ENT surgeon who conducts the operation on the pharynx or larynx, two parts of the body with particularly intensive reflex response to any stimuli.

The anesthetics are administered during the whole operative procedure. A few minutes after they are not given any more, and once the operation is over, they stop being effective and the patient wakes up. The anesthesia is performed by a specialized anesthesiologist who, as previously said, in order to decide the anesthetic plan takes into consideration factors related to patient's coexisting diseases and to the type of intervention.

Every patient under anesthesia has a different capacity to control the physiological respiratory function. To ensure normal respiration during the operation, several instruments are used such as various laryngeal tubes and trachea tubes, special high technology devices and respirators. Anesthetic medicines administered through intravenous injection or inhaling affect the patient's arterial blood pressure and heart frequency. Devices are therefore connected for a continuous monitoring of the patient's vital functions.

During the operation the anesthesiologist closely monitors the patient's condition and the data provided by the medical equipment and intervenes according to the information he / she receives.

Once the operation has been concluded the anesthetic is no longer administered and the patient completely recovers consciousness and his /her respiratory functions. Afterwards the patient is taken from the surgery room to the recovery section where he/she is monitored for another period of time before being transferred to his/her bed.

It is important to mention that the anesthesiologist may consider it necessary to transfer the patient to the Intensive Care Unit for the first 24hours after the operation. This decision is made according to the seriousness of the operation, the duration of the anesthesia, patient’s coexisting diseases, and his/her overall physical condition (advanced age, heart or lung diseases, etc.).

Intravenous sedation

When the surgical procedure is short and not very difficult local anesthesia is used as an analgesic method. Nevertheless, the administration of additional intravenous analgesic and sedatives is considered necessary:

· In order for the surgeon to perform the local anesthetic technique in a safe and unobstructed way.

· In order to control fear and stress of a patient who will undergo the surgical procedure.

Conscious sedation

The term describes the situation during which the patient is in state of partial consciousness, he/she does not feel pain, he/she is able to talk with the anesthesiologist and the surgeon and he/she has an elementary perception / understanding of the situation without this state being unpleasant to him/her.

Deep sedation

The terms describe the state in which the patient is sleeping and has no perception of what is happening, but he/she does not stop breathing.

When the patient is in the surgery room, a venous line is placed in him/her and is connected to the equipment that monitors the vital functions such as arterial blood pressure, heart frequency, blood oxygenation. Afterwards, small amounts of anesthetic medication are gradually administered in order to reach the desirable level of sedation.

Sometimes it is possible that a light sedation may change to a deep sedation or to a general anesthesia if:

· The patient cannot tolerate the surgical stimulus and therefore does not cooperate.

· The anesthesiologist considers this necessary for the patient’s safety or

· If the surgeon considers it necessary so as to improve the surgical conditions.

The intravenous sedation is considered an absolutely safe anesthetic method, as long as is performed in continuous monitoring of the patient's vital function and conducted by a professional anesthesiologist who is able to provide an immediate and vital support.

At this point it must be stressed that the preoperative discussion with the anesthesiologist about the patient's medical history is absolutely necessary whereas the preoperative medical tests are not always necessary. Once the surgery has been concluded, the patient remains in the recovery room for a period of time depending on the type of the sedation administered. The patient does not leave the hospital alone but he/ she is always accompanied by a family member and with instructions involving any oral medication prescribed.

The nature and type of the surgical intervention determines when the patient can return to his normal daily activities. This period of time does not usually exceed 24 hours.

Epilogue

It is quite common that patients who are to undergo an operation feel anxiety and fear for the anesthesia. However, right preparation, review of the medical history and frank and substantial communication between the patient and the anesthesiologist will reveal potential problems and minimize potential dangers, establishing a trust building approach and eliminating the patient's fears.