There are a variety of drugs and methods used to provide safety and comfort with anesthesia during surgical and medical procedures. Rest assured that in almost all cases you will be asleep regardless of the anesthetic technique. The anesthetic methods vary primarily by the size of the area being anesthetized and the depth or density of the anesthesia. The area anesthetized may be a small area of skin, a limb or body region, or the entire body. The depth or density of the anesthesia varies from a calm, pain free state, to a light sleep, to a total block of movement and sensation, with or without complete loss of consciousness and all protective reflexes. Your Anesthesiologist will discuss your anesthetic options with you. With consideration of your medical history, your desires related to the anesthetic and the needs of your surgeon, the Anesthesiologist will guide you toward the best anesthetic approach. In general, the anesthetic techniques used to get you through surgery are as follows:
General Anesthesia
General anesthesia places your entire body in a state of sleep. More specifically, general anesthesia involves total loss of consciousness, loss of spontaneous movement, loss of response to a surgical stimulus, and, importantly, loss of all protective reflexes, including airway protection and sometimes spontaneous breathing. Under general anesthesia a patient does not feel or remember anything. General anesthesia can be delivered with intravenous medications but typically is achieved through a combination of Intravenous (I.V.) and inhaled anesthetics. The assistance of an anesthesia machine and a breathing device is often necessary to deliver and measure anesthetic and respiratory gases. The most commonly used breathing device is an endotracheal tube, a soft flexible tube temporarily placed into the wind pipe (trachea) by the Anesthesiologist, while the patient is asleep. This process is called intubation. Endotracheal tubes are put in place after patients are asleep, and removed (extubation) as patients are waking up before they are able to form memories. Only in rare and exceptional circumstances, where it is necessary for patients’ safety, is intubation or extubation carried out partially awake. In this type of circumstance every effort is made to keep patients comfortable throughout the process of establishing safe anesthesia. For many surgeries, however, less invasive devices are used to assist breathing and monitoring. Our Anesthesiologists will discuss all of your anesthetic options and seek to provide you with a safe anesthetic in the least invasive way possible.
Regional Anesthesia
Regional anesthesia for surgery involves fully anesthetizing a portion of the body, potentially allowing the use of lighter anesthetics instead of general anesthesia to provide the patient with calm, amnesia or sleep. With most regional anesthetics, additional medications are used so that patients sleep throughout their procedures. In some situations, it is necessary or desirable for a patient to be awake or to participate during a procedure. With a regional anesthetic a patient can be fully awake and feel no pain during surgery. A perfect example of this anesthetic is spinal anesthesia for Caesarean-Section, where a woman under spinal anesthesia is able to be fully awake for the surgical delivery of her baby. Regional Anesthesia can also be used for post-operative pain relief (analgesia). It can provide partial or total blockade of nerve sensations from the surgical site for a prolonged period of time. This blockade gives the patient excellent pain relief with very little medication, potentially sparing them from the exposure, side effects, and possible risk of General Anesthesia.
There are two types of Regional Anesthetics:
-
Neuraxial Blocks (spinals, epidurals and caudal blocks)
-
Peripheral Nerve Blocks (target nerves or nerve groups going to the arm, leg, shoulder, neck, chest, groin or abdomen)
All of these techniques require injections and can be done with patients awake, under sedation, and occasionally under general anesthesia. Most needles used for regional anesthesia are very small. In the Operating Room, almost all patients are given sedating medicines that make them calm and comfortable during block placement. The skin site for the block is also anesthetized with lidocaine. The block is then placed, and additional medicines are given so that patients are comfortable or asleep throughout the remainder of their procedures. Though all things in medicine carry some risk, regional anesthetics have been shown to be exceedingly safe in experienced hands. The experienced members of our group literally place thousands of regional anesthetics every year.
Neuraxial Blocks
Neuraxial anesthesia, made up primarily of spinals, epidurals and caudal blocks, can be used for surgery in the lower extremities (feet, legs and hips), pelvis and lower abdomen. These blocks are placed by a slow, careful injection in the appropriate position along a patient’s spine, after the injection site has been made numb by a small amount of lidocaine local anesthetic. Using very small needles, Spinals deliver medication directly to the spinal fluid, causing rapid and excellent quality anesthesia of the blocked area. Epidurals delivery medication to the spinal nerves as they pass through a tissue layer outside the spinal canal and slightly closer to the skin. Sometimes, when the needle is removed, a very small plastic tube is left in place so that medication can be given continually for an extended period, usually for pain relief after surgery. These procedures are carried out in a relaxed, comfortable way, and are generally very well tolerated. They have been used for decades to provide safe anesthesia, and in some cases can decrease the risk of post-operative complications. They have a long established safety record and ongoing improvements in design and delivery, including needle shape and ultrasound guidance, have continued to enhance the safety of using neuraxial anesthetics for patient benefit. Neuraxial Anesthetics are safe and effective and may be your best anesthetic plan. Please relax and let us guide you through your anesthetic options.
(Note: Epidurals are used to provide safe and beneficial pain relief for the vast majority of laboring mothers in hospitals in the United States.)
Peripheral Nerve Blocks
Peripheral Nerve Blocks interrupt sensations from individual nerves or groups of nerves as they travel back toward the spinal cord. Anesthesia for major hand surgery is a common example, where an injection in the upper chest or shoulder makes the hand and arm numb and the hand repair can take place without the patient feeling it. Though we do use nerve blocks for surgery, they are most often used to provide pain relief after an operation. In this capacity, nerve blocks can provide relief lasting hours or even days. With a patient under sedation, the blocks are placed using an injection with a small needle that is guided into position using subtle electrical current, ultrasound visualization or both. Ultrasound allows the Anesthesiologist to see the position of the needle under the skin in relation the nerves and other nearby anatomic structures and has greatly enhanced the speed, accuracy and safety of peripheral nerve blocks. Members of our department have performed thousands of these procedures and will gladly talk over your options for pain relief and anesthesia from peripheral nerve blocks.
Local Anesthesia
This technique is simply the injection of an anesthetic medicine like Lidocaine to an area of skin and underlying tissue at the site of surgery. It can provide numbness to a limited part of the body for small, superficial surgeries. Additionally, local anesthetics are often injected around surgical incisions to assist with pain relief in the immediate postoperative period. For surgeries done with local anesthesia, intravenous sedation is almost always additionally administered. With limited surgical and anesthetic exposure and excellent pain relief postoperatively, the combination of local anesthesia and sedation is a common and trusted method for providing a safe and comfortable operative experience.
Intravenous (IV) Sedation / Monitored Anesthesia Care (MAC)
Depending on the surgery, you may not need a deep anesthetic, and may have your best anesthetic experience by receiving intravenous sedation. Intravenous sedation, also called Monitored Anesthesia Care, can be tailored to the depth of anesthesia you need and is often used along with local or regional anesthetics. Most often when receiving sedation, you will not have any memory of the experience and it will feel as though you entered the operating room and then slept through the entire procedure. However, in discussion with you and your surgeon, your Anesthesiologist will design an appropriate sedating anesthetic and then adjust the level of sedation throughout the procedure in relation to the requirements of the procedure itself, your comfort, and your safety. These are great anesthetics and patients who receive them tend to be very satisfied and do very well postoperatively.
Levels of sedation can be broken down in to minimal, moderate and deep. Minimal sedation provides you with calm and comfort. When minimally sedated you may be awake or partially awake, have some awareness, and may be able to communicate with your doctors. You may or may not remember anything about the experience. This kind of light anesthesia is necessary in some situations and appropriate for patients desiring it, for procedures requiring patient participation, and for patients with certain medical problems or severe illness.
With moderate sedation, you will generally sleep through the entire procedure, though it is possible for you to have a brief, vague memory of the operating room, or to be quickly awakened, either briefly for your safety or for your participation in the procedure. For example, your Anesthesiologist may awaken you and ask you to take a couple of deep breaths and then allow you to fall back asleep. You are unlikely, however, to remember being in the operating room
Deep sedation is often used by anesthesiologists to provide patients with a smooth and stable operative course and no memory of a procedure. It allows for some more invasive procedures to be accomplished without general anesthesia and allows or requires the anesthesiologist to provide supportive care to patient while they are asleep. In general, patients do not awaken easily while under deep sedation, though, depending on the procedure and anesthetics used, an Anesthesiologist may at times move a patient from deep to light anesthesia and back. Recovery after a procedure under deep sedation may or may not be longer than with lighter sedation. Most patients, however, will be awake within a few minutes of the procedure ending.
Providing intravenous sedation is a challenging aspect of medical care, but one that, in the right hands, brings great results. All of these sedative anesthetics are safest and best delivered by an Anesthesiologist. Our Anesthesiologists use their experience and expertise to tailor sedation to a patient’s body, history and procedural needs, as well as to maintain physiologic homeostasis and safety throughout the anesthetic and on into recovery.