What is an Anesthesiologist

Anesthesiology is a field in medicine that deals with the use of drugs for pain relief and total care of a surgical patient before, during and after surgery. The term was initially adopted by the University of Illinois in January 1912 to mean “the science that treats of the means and methods of producing in man or animal various degrees of insensibility with or without hypnosis”. The term anesthesia is derived from the Greek word ?ναισθησ?α (anaisth?sía), from ?ν- (an-, “not”) with α?σθησις (aísth?sis, “sensation”).


In American English, a nurse who has completed a degree program in anesthesiology is called an anesthetist. They are trained to administer anesthesia to patients. On the other hand, physicians who practice anesthesiology and have completed the required medical education programs are called anesthesiologists. Anesthesiologists are medical doctors who are trained to make decisions regarding patient anesthesia, along with the regular responsibilities allocated to nurse anesthetists. This distinction comes from Dr. Matthias J. Seifert in Chicago who, in 1902, asserted that an anesthetist is a technician while an anesthesiologist is the scientific authority on the field. However, it should be noted that even this distinction is not universal. In British English, medical doctors specialized in anesthesiology are called anesthetists while nurses specialized in anesthesiology are called nurse anesthetists.


Roles and Responsibilities


An anesthesiologist is tasked with making a patient’s experience with pain as easy and as comfortable as possible. In America alone, around 40 million anesthetics are used in a variety of cases and operations. Anesthesiologists play a big role in these procedures. They participate and provide care in about 90 percent of those cases.


In America, a team of anesthesiologists is called an Anesthesia Care Team. The team is composed of several anesthesiologists of varying educational attainment. A physician anesthesiologist serves as the director of the team. The physician anesthesiologist is responsible for the management of personnel, the preanesthetic evaluation, as well as the prescription and the management of the anesthetic and post anesthesia care. The Anesthesia Care Team consists of anesthesiology assistants and nurse anesthetists.


Anesthesiologists are perioperative physicians. This means that they have responsibilities prior, during and after surgical operations. Prior to a surgery, physician anesthesiologists and anesthesiology assistants go over every detail of a patient’s medical history and physical condition to develop the correct mixture of anesthetics. Common considerations during the preoperative examination include the patient’s body mass, age, previous medical conditions, allergies, and drugs previously taken, among others. In some cases, severe alcoholism interferes with the efficacy of certain anesthetics. Once an anesthetic is formulated, it is also the physician anesthesiologist’s responsibility to explain the different anesthetic options available to the patient and its associated risks.


Aside from administering the anesthetic, anesthesiologists are also responsible for monitoring the vital signs of a patient, such as heart rate, blood pressure, heart rhythm, body temperature and breathing during the surgical operation. Anesthesiologists also regulate the input of anesthetics depending on those factors. Should something go wrong with the vital signs of a patient, anesthesiologists and anesthetists are the first ones to respond accordingly.


After a surgical procedure, a patient is sent to a Post Anesthesia Care Unit (PACU). It is normal for patients to feel certain after effects of anesthesia. These include nausea and vomiting, confusion, muscle ache, sore throat, itching, hypothermia, and in rare cases, delirium, cognitive dysfunction or hyperthermia.


It is the anesthesiologist and anesthetist’s responsibility to perform postoperative care and evaluation with a pain management plan. A good pain management program is necessary after the operation because it reduces the risks of postoperative complications like heart attack, pain, shock, and others. When the anesthesiologist is sure that the patient has recovered from post anesthetic effects, the anesthesiologist releases the patient from the PACU to their own room or for discharge.




Expertise in anesthesia involves many subspecialties. Anesthesiologists may further train and obtain certification for these.


Ambulatory Care Anesthesia is an area of care that allows patients to have surgery on an outpatient basis. Depending on the complexity and type of procedure, some may be done as outpatient surgery. This means that a patient may be able to go to a hospital to have surgery, receive the necessary post-operative care, and leave the hospital, all in the same day.


Preoperative evaluations are done remotely, with nurses contacting patients regarding their medical history and pre-operative medical instructions. Upon arrival of a patient to the hospital on the day of the surgery, an anesthesiologist specialized in ambulatory care performs all the other necessary pre-operative evaluations that cannot be done remotely. He then formulates the appropriate anesthetic and discusses it with the patient. Afterwards, the surgery is performed.


The standards are the same between inpatient care and outpatient ambulatory care. So there is no compromise in effect or quality. While not all treatments are available or practiced as outpatient surgical procedures, when they are, they are very convenient and cost-effective for the patient.


Critical Care Anesthesia is the care for patients with life threatening conditions. This specialization requires anesthesiologists to constantly monitor a broad array of patient information. They must also be able to quickly respond to the variety of problems that life threatening conditions may cause in various parts of the body. Patients admitted into critical care units vary from infants to older adults, which adds to the difficulty of critical care anesthesiology.


Neurosurgical Anesthesia, while very similar to general anesthesia, may uniquely affect the blood flow, blood pressure and energy consumption of the brain and the spinal cord. Special training is therefore required on the properties of the brain and spinal cord and their responses to anesthetics. Neurosurgical anesthesiologists’ specific expertise is required in several cases, such as head trauma, spinal surgery, pediatric neurosurgery, brain biopsy procedures, benign and malignant intracranial tumors.


Neurosurgical anesthesiologists are also involved in a unique kind of operation called a sitting craniotomy. It may be an explorative or a corrective surgical procedure performed on the brain that requires the patient to be in a sitting position, rather than the usual supine position. The sitting position provides the neurosurgeon a better view of the brain while positively affecting the blood and fluid pressures around the brain area. It also provides the neurosurgical anesthesiologist better access to the chest area to regulate breathing, blood pressure and other vital signs. The patient may be conscious during the operation and may even respond to the operating team’s questions but should not feel any surgical pain.


Obstetric Anesthesia becomes a subspecialty of its own due to the unique circumstance of the anesthesia possibly affecting two bodies — the mother and the child. The anesthesia applied to the mother in labor may affect some aspect of the infant. Thus, special consideration must be applied on the location of the application of anesthetic drugs. Typically, a regional anesthetic is applied to the mother’s spine to numb pain to the lower part of the body. Research has shown that this kind of anesthetic application is safe for both the mother and the baby. However, regardless of what research predicts, mothers may still respond differently to anesthesia. Some find its effects to be sufficient throughout labor, while some still experience pain as labor progresses. Fear not though, as severe complications are extremely rare.


Pediatric and Neonatal Anesthesia specifically deals with children patients. They must focus on alleviating the fears of the child as well as his parents. This is done by explaining the procedures to be performed using the simplest terms possible, as well as showing the patient and his/her family the materials to be used, such as the inhalation mask. Anesthetic by inhalation or by topical application is preferred on children over injection methods. Fragrances like candy are often added to the anesthetic gas to make the experience more pleasant for the child. These measures are carefully undertaken to prevent panic or anxiety in the child since these reactions could delay or disrupt the procedure as a whole.


There are also differences between adults and children with respect to their responses to anesthetics. These include the time of recovery from post-anesthetic effects. Surprisingly, infants and children are generally known to recover faster from anesthesia, surgery and pain compared to adults.


Pain Management is another specialty that anesthesiologists may explore. Pain by itself is a complex subject, with manifestations ranging from acute to chronic pain. It may also have numerous causes like injury, nerve damage, surgery, and cancer. Pain management anesthesiologists must be skilled in diagnosing pain conditions, prescribing appropriate medicine as well as performing the necessary procedures for a wide variety of patients. It is common to find pain management anesthesiologists coordinating with doctors from other fields such as physical therapy or psychological therapy to facilitate a multidisciplinary approach in creating a pain management plan. Pain may be treated with a variety of methods, such as chiropractic treatment, epidural anesthetics, acupuncture, physical therapy, and oral medication.  




Anesthetic education is mostly the same globally, despite the superficial difference in title name. Physician anesthesiologists, like other medical doctors, must complete a four year undergraduate pre-med course, followed by four years of medical school, as well as a four-year anesthesiology residency program after that. Many physician anesthesiologists follow their eight year medical education with an additional year of fellowship training in specializations like cardiac anesthesia, obstetric anesthesia, pediatric anesthesia, neuroanesthesia, critical care medicine or pain management. They may also follow this up with certification in critical care medicine, pain medicine or hospice and palliative medicine after additional training and examination.


Anesthesiology assistants are health professionals who pass the National Commission for Certification of Anesthesiologist Assistants examination. The examination is provided by the National Board of Medical Examiners. Prior to taking the exam, the anesthesiology assistant must have completed a four year pre-med undergraduate course which should include topics in anatomy, biochemistry, pharmacology and physiology. The course must also include topics on the body’s cardiovascular, nervous, neuromuscular, renal and respiratory systems. They may not practice medicine outside of anesthesiology either. Additionally, they may not practice anesthesiology without the supervision of a physician anesthesiologist.


Nurse anesthetists are required to have completed a Bachelor’s Degree in Science. They must also gain at least one year’s worth of practice before entering a 2 to 3 year nurse anesthesia program which includes topics in anatomy, chemistry and biochemistry, physiology and pathophysiology, pharmacology and physics. Following that, they must pass a national certification examination before becoming a certified nurse anesthetist.




The first recorded public use of anesthesia as we know it today is dated on September 30, 1846. Prior to that, various drugs, herbs, and opiates have seen recorded use as a way of attaining trance-like states, or partial or complete unconsciousness in various literature. In Roman historian Herodotus’ Histories, for example, the Scythians were recorded to have used hemp as part of a post-burial cleansing ritual. Roman natural philosopher Pliny the Elder, in The Natural History, described the use of mandragora as an inhalant anesthesia prior to crucifixions. Greek physician Galen, in De Simplicibus, suggested medicinal uses for opiates and mandragora. Indian surgeon Sushruta is known to have used strong alcohol and cannabis vapors to sedate patients while performing surgeries. Chinese surgeon Hua Tuo used a preparation of hemp and wine as an anesthetic.


While there are several other mentions of various herbs and mixtures to alleviate patient pain, surgery remained to be a last and desperate resort until the discovery and widespread use of anesthesia. Surgery is described in multiple accounts as terrifying and excruciating. An account of the horrors of pre-anesthesia surgery was recorded by Fanny Burney, who was diagnosed with breast cancer in 1811 and had to go through a mastectomy. Her account is as follows:


“When the dreadful steel was plunged into the breast—cutting through veins—arteries—flesh—nerves—I needed no injunctions not to restrain my cries. I began a scream that lasted unintermittingly during the whole time of the incision—& I almost marvel that it rings not in my Ears still!”


A similar account is dated 1828, when Stephen Pollard received a surgical operation to remove a bladder stone, which should have take five minutes to complete. However, his operation took an hour to complete, while he begged his surgeon, Bransby Cooper, to “…let it go! Pray, let it keep in!”. Pollard passed away the next day. Surgeons felt apprehensive about surgery at the time too. John Abernethy, an English surgeon, was known to become physically ill and to shed tears prior to or after an operation. He likened the walk to the operating room to the journey to a hanging.


The invention of anesthesia may be dated around 1540, when German physician and botanist Valerius Cordus synthesized diethyl ether, which he called “sweet oil of vitriol”, from ethanol and sulfuric acid.


In 1729, German chemist August Sigmund Frobenius had developed the first recorded detailed description of diethyl ether, which he named ether. Ether would eventually be formally used as a general anesthetic, but would be replaced by other drugs due to its flammability.


On April 9, 1799, Sir Humphrey Davy used nitrous oxide, otherwise known as laughing gas, to provide relief from pain. In particular, he used laughing gas to relieve a headache as well as pain from the removal of his own wisdom tooth. He suggested the use of nitrous oxide in surgical operations. It saw practical use in surgery half a century later. Laughing gas is still in use as an inhalant anesthetic for pediatric patients.


In 1806, Friedrich Wilhelm Adam Serturner, a German pharmacist, extracted morphine from opium. He used this on dogs, which caused sleep and indifference to pain. He then tested morphine on himself and three young boys in 1817. All four almost died. Currently, morphine is used to alleviate moderate to severe pain on an extended period of time. It is not used in an as-needed basis due to its addictive properties.


In 1831, Chloroform was independently discovered by Samuel Guthrie, from America,Justus von Liebig from Germany and Eugène Soubeiran from France. It was usually available in liquid bottles. To use it, one poured it on a cloth and then pressed to the mouth for the person to inhale.


In 1842, Dr. Crawford W. Long, an American surgeon and pharmacist, successfully used ether to relieve pain for the removal of a small tumor from the neck of a patient. He became familiar with the pain relieving properties of ether during his college days, where he used ether himself. He did not publish his discovery, but was still credited as the discoverer of anesthesia after his death.


On September 30, 1846, the first recorded successful use of ether as an anesthetic was performed by William Morton, an American dentist. Dr. Morton dropped and spilled a jar of ether and cleaned it with a handkerchief, the vapor of which he inhaled. He noted the numbing effects of ether and used it on one of his patients. The patient fell into a deep sleep that was reported to last about 45 seconds, at which time Dr. Morton removed a deeply rooted bicuspid tooth. The patient was reported to have felt no pain at all.


Dr. Morton then developed an ether inhaler, which he demonstrated in the operating room of the Massachusetts General Hospital. The operation it was used on was the removal of a tumor of the jaw, an operation that normally puts the patient under immense pain. When the ether inhaler was used, there were no signs of pain showed by the patient. This operation was performed on October 16, 1846. Despite the slow means of communication at the time, by December 15, 1846, ether was being used in Paris. By December 18, 1846, ether was used in London.


In 1847, Professor James Y. Simpson, a Scottish obstetrician, successfully made use of chloroform in childbirth operations. Prof. Simpson had previously used ether as an anesthetic, but noted its disadvantages. Prior to his use of chloroform in childbirth operations, he had used it on himself and two of his assistants. They noted a feeling of happiness upon inhaling the substance, followed by a deep sleep from which they woke up the next day. He would then use chloroform to put pregnant mothers undergoing labor to sleep. In his records, a patient on whom chloroform was administered, remarked that she “enjoyed a comfortable little sleep” and that “sleep stopped the pains”. His successful use of chloroform can be attributed to luck however, as it can be fatal depending on the dosage.


In 1848, Dr. John Snow, an English physician, developed an inhaler to regulate the chloroform intake of patients. This resulted in a reduction of deaths due to chloroform use. Dr. Snow also popularized the use of chloroform in childbirth operations by using the anesthetic on Queen Victoria for the delivery of Prince Leopold and Princess Beatrice.


In 1884, Karl Koller, an Austrian ophthalmologist, demonstrated the use cocaine as a local anesthetic for eye surgery. Performing eye surgery at the time was difficult due to the involuntary reflex responses of the eyes to any stimuli. Cocaine rendered the tissue of the eyes numb, which allowed Koller to operate on the eyes unimpeded.


In 1889, the Philadelphia College of Dentistry appointed Henry I. Dorr as the first Professor of the Practice of Dentistry, Anesthetics and Anesthesia. The American College of Dental Surgery would soon appoint George Leininger as its Professor of Anesthesia and the New York Homeopathic Medical College would do the same for Drysdale Buchanan.


Modern Anesthesiology


Modern anesthesia is categorized into three types: general, regional and local. General anesthesia renders a person unconscious. He feels no pain during surgery and will have no recollection of the events of the surgery after waking. General anesthesia is usually administered through injection, a breathing mask, or both.


A regional anesthetic is applied close to a cluster of nerves or the spinal cord to render an area of the body numb, such as the entire lower body. The two common regional anesthetics, spinal anesthesia and epidural anesthesia, are both administered in the spine. A patient may be given a sedative when such an anesthetic is used.


In contrast to the first two types, local anesthesia is injected into tissue, rendering specific areas numb. This is usually done for minor surgeries only. For such operations, the patient remains awake throughout the procedure but feels no pain.


Sedation techniques are often used along with anesthetics. Aside from its aid top pain relief, sedation also helps in relieving anxiety caused by treatments or diagnostic tests. Sedation techniques combined with regional or local anesthesia have fewer side effects than general anesthesia. Patients generally suffer less nausea and recover faster as well.


Sedation is divided into three categories: minimal, moderate and deep. Minimal sedation allows patients to feel relaxed yet remain conscious. Doctors may ask patients questions and patients have the consciousness to respond in this state. Moderate sedation is described with feelings or a state of drowsiness. Patients may fall asleep during this type of sedation, but can be easily awakened. During deep sedation, a patient will fall asleep until the medication wears off. The patient will have no recollection of the procedure and may have slow breathing while the sedation is in effect. Oxygen is usually provided for the patient in such an event to support his slowed breathing.





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