What is Anesthesia?
Anesthesia makes surgery possible for thousands of people every day. It blocks pain and relaxes you. It also keeps your body from moving during the procedure. For example, without anesthesia, your body’s reflexes would naturally cause an arm or leg to jerk away from something painful.
Without anesthesia, a surgical incision would also cause an increase in heart rate, changes in blood pressure, and other automatic defense mechanisms that our bodies use for protection. Anesthesia helps calm and relax the mind and body and control those natural defenses.
Today, there are a wide range of options for keeping you comfortable, including:
- general anesthesia,
- sedation,
- regional anesthesia that includes spinal, epidural, and nerve block anesthesia, and local anesthesia.
All of these options work by interfering with how your brain interprets pain signals transmitted by the nerves.
The type of anesthesia used for your procedure will be recommended by your care provider and the anesthesia team. This care team may include an anesthesiologist and a CRNA, short for certified registered nurse anesthetist.
The decision is based on:
- Your comfort needs
- What part of your body is being operated on, and
- Your overall physical condition
Let’s take a look at each of these different types of anesthesia and see how each one works, starting with general anesthesia.
General Anesthesia
General anesthesia is used when you need to be completely asleep during a procedure.
For general anesthesia, you will be given some combination of medicines injected into a vein in your arm or hand, and gases (anesthetics) that you inhale through a tube or mask.
It interrupts the brain’s overall ability to sense pain. You will not be conscious or able to move. You should not feel or remember the surgical procedure.
Because general anesthesia stops or slows down many of your automatic muscle movements, it can interfere with normal breathing.
To help you breathe during the surgery, you will likely be connected to a ventilator — a machine that helps you inhale and can help you exhale, while you are asleep. A ventilator blows air into your airways through a breathing tube, either an endotracheal, ET tube or a laryngeal mask airway (LMA).
Both types of breathing tubes are typically put in place after you are asleep and removed following surgery before you are fully awake.
Let’s understand how these two breathing tubes work.
An endotracheal tube is a special breathing tube that is put into your windpipe. Your doctor will carefully pass the tube through the vocal cords using a special scope (a laryngoscope).
The tube is removed after your surgery as soon as you can safely breathe on your own, often before you are fully awake.
The second option is called a laryngeal mask airway (L-M-A).
This breathing tube has a special mask at the end that rests in the throat. After the tube is placed, the mask is inflated to fit the airway and keep it open. The mask sits behind the tongue, above the vocal cords. It can be attached to a ventilator.
An LMA is useful for shorter surgeries and emergency situations.
You might experience some temporary side effects after general anesthesia,
these include:
- Nausea and vomiting,
- Muscle aches,
- Itching (especially from pain medicine sometimes given during the surgery),
- Chills and shivering, which may happen as you regain consciousness after surgery
If you are healthy, general anesthesia is a very safe way to keep you comfortable during surgery.
There are some risks associated with general anesthesia. These include
confusion or memory loss that is usually temporary. It is possible to have damage to the vocal cords, teeth or tongue.
Rare lung problems after general anesthesia can include:
- infection, pneumonia,
- or damage to the lungs, called a pneumothorax.
Rare but serious risks of general anesthesia also include
- heart attack, stroke, or
- malignant hyperthermia, a reaction to certain anesthetic drugs that cause a dangerous fever and muscle spasms.
- The risk of death from anesthesia is very rare, about 1 in 100,000.
Some people are at higher risk for problems associated with general anesthesia. You could be more at risk if you:
Drink too much alcohol or abuse medicines (like painkillers), Smoke, Have allergies to medications, or a family history of problems with anesthesia medication; risks are increased if you Suffer from heart, lung, or kidney problems
Sedation
Now let’s talk about Sedation. It is sometimes called conscious sedation and is different from general anesthesia. It is used during minor surgeries, shorter and less-complex procedures, such as a biopsy, colonoscopy, or even some dental surgery. It involves having a medicine called a sedative injected into a vein through an IV in our arm or hand. This sedative helps you relax and blocks pain. Other medicines called analgesics may be given to provide pain relief.
Sedation can be:
Deep — You will feel like you are asleep, and you will not remember the procedure.
Moderate — You will feel sleepy and may actually fall asleep. You may or may not remember the procedure.
Light — You will be relaxed enough to feel drowsy but will be awake. You will be able to understand and answer your doctor’s questions and follow directions. You will likely remember some of the procedures.
When you have sedation, you feel sleepy very quickly. Your healthcare provider will keep track of your blood pressure and breathing during the entire procedure. Even if you do not fall asleep, you may not remember much about the procedure.
Sedation allows you to recover quickly. However, you will need to have someone to drive you home as you may be a bit drowsy for a few hours afterward.
Sedation is very safe but can have risks similar to general anesthesia. Especially during very deep sedation, it can be necessary to help the patient breathe with a mask or airway device.
Other risks include allergic reaction, headache, nausea, and the sense that sedation was too light.
Local Anesthesia/Spinal Anesthesia
What we call local anesthesia, blocks the pain signal locally at a location near the procedure site -. usually with an injection that numbs the area. You may receive a sedative — but usually, you remain awake.
Now let’s talk about spinal and epidural anesthesia. Both of these anesthesia methods are used to numb the entire lower body for certain procedures. A local anesthetic is injected into a space between the backbones. You will be asked to sit up or lie still on your side for the injection.
For a spinal, a needle is guided between the bones to reach the fluid in your spinal canal. Medicine is injected into the fluid.
This works very quickly and takes a few hours to wear off.
You may also receive medicines (sedation anesthetic) through an IV in your arm or hand to help you relax or sleep.
Epidural anesthesia is similar. A needle is used to insert a thin catheter in the space just outside the spinal canal. The anesthetic medication is then injected through the catheter. Epidural anesthesia can take several minutes to become effective.
The catheter can be used more than once to give additional medication easily.
Both spinal and epidural anesthesia are very safe and effective, with fewer side effects than a general anesthetic.
Whether or not a spinal or epidural is recommended depends on the procedure you are having and your overall situation.
Sometimes a spinal or epidural is tried but not successful. The exact space in the spinal canal may not be located with the needle, or numbness for blocking pain is not enough. In these situations, general anesthesia can be recommended.
The most common side effects of this type of anesthesia can be
- Minor back pain (where the needle was inserted) or
- A temporary drop in blood pressure, or
- the unusual sensation, numbness with breathing. This can be disturbing but your care provider will reassure you by monitoring your oxygen levels as you breathe normally.
Less common risks can include:
- A severe headache is called a spinal headache.
- Hematoma (which is bleeding around the spine where the needle was inserted)
- Difficulty urinating (peeing) due to numbness,
- Allergic reaction, and very rarely there can be
- Nerve damage,
- Meningitis or an abscess, or
- Seizures.
Although not a complication, it is important to let the full effects wear off before trying to get up or move around without assistance. You could be at risk for falling if your legs haven’t regained full feeling.
General Risks of Anesthesia
Risks associated with anesthesia vary depending on the type of anesthesia you have, your overall physical health, and how closely you follow your doctor’s instructions prior to surgery.
Many risks are related to temporary side effects.
In general, there are more risks with general anesthesia than with other types.
Some patients are at higher risk to start. This can be true for children, the elderly, people that are overweight or obese, and people that suffer from obstructive sleep apnea (O-S-A).
People with known medication allergies, a previous reaction to anesthesia, and those with chronic medical conditions are also at higher risk.
People who smoke or abuse substances (such as alcohol, pain relievers, or street drugs) will have much more trouble recovering from anesthesia as well as having a greater risk for complications.
For those over 65, normal processes of aging increase the risk for different anesthesia side effects and complications. It can impact memory and thinking.
Another problem is called postoperative delirium. This is temporary and happens within a few days after the surgery.
And a more serious condition is called postoperative cognitive dysfunction (POCD), which can cause more long-term thinking problems.
If you are over 65, and depending on your situation, you may be referred for a preop evaluation with a physician skilled in caring for patients over 65, called a geriatric specialist. You may also be given a mental function test to help understand any changes that occur afterward. Alert your family and caregivers at home to watch for confusion.
For patients who have a high BMI, body mass index, or are obese, general anesthesia can present special problems, including difficulties placing a breathing tube and breathing problems that result from anesthesia drugs.
If you can lose some weight prior to surgery, you can positively impact your surgery and recovery.
They may also position you a bit differently to make breathing easier.
For a while after surgery, you will likely receive oxygen through a facemask and be coached to breathe deeply.
It is very important that you let your doctor know if you have ever had difficulty with intubation, breathing tube, or airway device during prior surgery.
Obstructive sleep apnea (OSA) happens when breathing becomes blocked and sometimes stops for short periods during sleep. Over time, this condition can lead to heart, lung, and memory problems.
Obesity is a risk for OSA. If you snore loudly, have periods during sleep where you stop breathing, according to a sleep partner or feel overly sleepy during the daytime you may have OSA.
[Other symptoms can include having morning headaches, problems with concentration, memory problems, irritability, decreased libido, or frequently having to get up to urinate (pee) at night.]
If you suspect that you have untreated OSA, let your doctor know.
When having an anesthetic, even small amounts of sedation can cause problems with both your airway and how your heart and lungs respond to the stress of the surgery. For general anesthesia, the risk of complications is higher. Your surgical team can take steps to help prevent OSA-related complications by:
- Avoiding or limiting opioid pain medications,
- Using continuous positive airway pressure (C-PAP) before and after surgery, and
- Carefully monitoring your care after surgery. If you use a continuous positive airway pressure (CPAP) machine at night at home, your doctor will need to know the pressure setting for the machine and may want you to bring it with you to the hospital for use following surgery.
One of the best ways to lower your risk of complications is to pay close attention regarding preparation for any surgery or procedure. For example, you will need to make sure you tell your doctor about all medicines you take.
These include prescription medicines as well as over-the-counter drugs, inhalers, patches, herbal remedies, vitamins, and any street drugs.
Knowing what you are taking, and planning for stopping these before surgery, if necessary, could save your life.
Also, pay attention to when your doctor advises stopping eating or drinking before surgery. If you have food in your stomach when you are given anesthesia, you could vomit and have food or fluids get into your lungs. This can result in a serious kind of pneumonia or even be fatal.
If you have ever experienced any allergic reaction to anesthesia or to any other substance, be sure to let your surgeon or anesthesiologist know well beforehand.
Recovering from Anesthesia
After your surgery or procedure, the anesthesia drugs you were given (either gas inhalation, or injection) will stay in your body for as much as 24 hours.
If you have general anesthesia, you will likely go to a recovery room in the hospital or outpatient clinic. There, healthcare providers will continue to monitor your breathing, blood pressure, and general health until you are able to go home or move to a hospital room if you had major surgery.
You may be given medicine for pain or nausea if you need it after the anesthesia wears off.
During recovery, you may have some side effects or feel just fine. It is important to remember that anesthesia drugs are still affecting you and that they may interact negatively with other substances that enter your body.
To make sure your recovery goes as smoothly as possible, here are some important things you can do during this first 24 hours after receiving anesthesia drugs:
- Have a responsible adult available to take you home and even stay with you for the first 24 hours,
- Rest for at least a day after going home. Ask your doctor when you should return to work.
- If you have small children, get someone to care for them at least the first day.
- Work up to full meals. Start with light, easy-to-digest foods like soup, crackers, toast, rice, or yogurt to make sure you avoid discomfort. Your digestive system may need a bit of time to fully wake up from anesthesia.
If you have general or sedation anesthesia, you may feel awake quickly. However, these medications can impair your thinking for several hours. Some patients notice effects for days.
If your procedure is done as an outpatient, understand that you will need a ride home. Plan to rest.
Use all medication with care and only as instructed by your doctor, and call if you have questions or concerns.
Do not drive, operate machinery, make important decisions or drink alcohol until the next day.
You may be told to restrict your activity for 24 hours. Be sure you understand your personal instructions.
Call 911 if you have chest pain, shortness of breath, dizziness, bleeding that doesn’t stop, and any other sign that you may be having a complication from the procedure.
Hospital admission, medication, or surgery may be needed to correct some problems.
The particular surgery or procedure you are having works well with the anesthesia options your doctor has discussed with you. Which type you decide on depends on personal preference (for you and your doctor), your overall health, and the type of surgery or procedure you are having.
Your anesthesia team will monitor your health at all times and make sure that your experience goes as smoothly as possible.
