In addition to the above assessment, the anesthetic plan must consider the wishes of both patient and surgeon, as well as our individual skill and experience. Does the patient have special requests that need to be taken into account? For example, some patients would like to be awake (maybe the President so he doesn’t have to pass control of the US to the Vice-President), others asleep, and others do not want “a needle in the back.”
Some patients present special problems, for example Jehovah’s Witnesses who do not accept blood transfusions, based on their interpretation of several pas-sages in the Bible (for example Acts 15:28, 29). A thoughtful and compassion-ate discussion with the patient usually finds the physician agreeing to honor the patient’s wishes, an agreement that may not be violated. The caring for children of Jehovah’s Witnesses brings an added concern and may require ethics consultation and perhaps even referral to a court. Again, these issues are best brought out days prior to surgery at a scheduled pre-anesthetic evaluation.
Numerous studies have failed to demonstrate that a particular inhalation anes-thetic, muscle relaxant, or narcotic made for a better outcome than an alternative. Yet, over the years, actual or perceived differences and conveniences have caused some drugs to disappear and others to establish themselves. Given an array of options, we can often consider different approaches to anesthesia, which we can discuss with the patient. We should always recommend the approach with which we have the greatest experience and which we would select for ourselves or a loved one.
The choices depend on several factors, first of which is the surgical procedure. For example, the site of the operation, e.g., a craniotomy, can rule out spinal anesthesia. The nature of the operation, e.g., a thoracotomy, can compel us to use an endotracheal tube. For the removal of a wart or toenail or the lancing of a boil, we would not consider general anesthesia – unless the patient’s age or psychological condition would make it preferable. The preferences of the surgeon might also be considered.
This introduces the patient’s condition as a factor in the choice of anesthesia. For example, a patient in hemorrhagic shock depends on a functioning sym-pathetic nervous system for survival and therefore cannot tolerate the sympa-thetic blockade induced by spinal or epidural anesthesia. A patient with an open eye can lose vitreous if the intra-ocular pressure rises, as might occur with the use of succinylcholine. Vigorous coughing at the end of an eye operation might do the same and must be avoided. Respiratory depression and elevated arterial carbon dioxide levels can increase intracranial pressure with potentially devas-tating effects in patients with an intracranial mass or hemorrhage. In obstetri-cal anesthesia, mother and child have to be considered. Here, we do not wish to depress uterine contraction nor cause prolonged sedation of the newborn child. Some agents used in anesthesia rely on renal excretion, others on hepatic metabolism, thus tilting our choice of drugs in patients with renal or hepatic insufficiency.
In the majority of patients, however, it makes little difference what we pick. We could choose one or the other technique for general anesthesia, using one or the other intravenous induction drug and neuromuscular blocker, and relying on one or the other inhalation anesthetic. We can supplement such a technique with one of a number of narcotic drugs available to us, or we can use total intravenous anesthesia. When we use general anesthesia, we can intubate the patient’s trachea and let the patient breathe spontaneously, or we can artificially ventilate the patient’s lungs. Instead of an endotracheal tube, we have available the laryngeal mask airway, preferably used in spontaneously breathing patients or, in the very old-fashioned approach, we might use only a face mask.
In many instances, we have options, the choice of which will be influenced by our own experience and expertise. For example, anesthesiologists with extensive experience in regional anesthesia will select that technique in preference to gen-eral anesthesia in cases where either technique can prove satisfactory for patient and surgeon. Examples include many orthopedic operations or procedures on the genitourinary tract.
In summary, many factors can influence the choice of anesthesia. In the major-ity of patients, however, we have the luxury of making the choice influenced by our own preference and routine (Fig. 1.1).
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