Spinal Anesthesia

Spinal anesthesia is a very common type of regional anesthesia that numbs the lower part of your body. Your provider gives two injections of a local anesthetic: one to numb your skin and one into the fluid around your spinal cord (called the subarachnoid space). The medicine quickly numbs specific body parts and relaxes your muscles.

Spinal anesthesia isn’t the same as an epidural. For an epidural, you get the medicine through a small tube, and providers can adjust or continue it longer if needed.

Your care team will help decide if this option fits your needs for the type of surgery you’re having.

When is a spinal anesthetic used?

Anesthesiologists often use this type of numbing for surgeries on the lower part of your body. You may need it for procedures involving your:

• Lower abdomen (the area below your belly button)
• Lower extremities (your hips, legs, knees or feet)
• Pelvis (your hips and lower belly)
• Perineal region (the area between your genitals and anus)

Spinal anesthesia is useful for:

• Procedures where general anesthesia may not be needed
• Shorter procedures

Common examples include:

• C-sections
• Hernia repairs (in your lower abdomen)
• Hip replacement
• Knee replacement

Anesthesiologists may use spinal anesthesia by itself or combine it with general anesthesia. If you get spinal anesthesia, you’ll still get sedation, so you’ll be sleepy during the procedure.

Who shouldn’t have spinal anesthesia?

Spinal anesthesia isn’t safe for everyone. Your care team will review your health history before deciding.

You may not be a good candidate if you have:

• A bleeding disorder or take blood thinners: Your provider will let you know if it’s safe.
• An infection at the injection site: The needle could spread the infection into your spinal fluid.
• Certain neurologic conditions: Your provider may carefully weigh the risks and benefits for some conditions.
• Certain serious heart conditions: Conditions like severe aortic stenosis may cause a sudden drop in blood pressure.
• High intracranial pressure (pressure inside your skull): A spinal injection could change fluid pressure and cause harm.
• Very low blood volume: Your blood pressure could fall too low.

How does spinal anesthesia work?

Spinal anesthesia works by blocking pain signals before they reach your brain. A provider injects numbing medicine into the fluid-filled space around your spinal cord. This fluid (called cerebrospinal fluid) protects your brain and spinal cord. The medicine surrounds your spinal nerves and stops them from sending pain signals upward.

Because of this, you won’t feel pain in the lower part of your body.

The medicine also surrounds the nerves that allow you to move your muscles, so you may also have trouble moving your legs for a short time. This is expected.

What are the steps to have the spinal anesthetic?

The exact procedure varies based on what type of surgery you need. Here’s what you might expect if you get spinal anesthesia:

1. Monitoring and IV: You’ll have an IV before your spinal starts. Your team will closely watch your blood pressure, heart rate and breathing. They may give you some sedation to help relax you before they start.
2. Getting into position: You’ll either sit up or lie on your side with your knees pulled toward your chest. This position helps open the spaces in your lower back. Your care team will help you stay comfortable and still.
3. Cleaning and numbing the area: Your provider will clean your lower back with an antiseptic to prevent infection. They’ll then give a small numbing shot in your skin, so it’s more comfortable when they place the spinal needle.
4. Placing the spinal needle: Your anesthesiologist will place a very thin needle into your lower back. They’ll guide it between the bones of your spine. You may feel pressure, but you shouldn’t feel pain.
5. Injecting the anesthetic: Once the needle reaches the subarachnoid space (the fluid-filled space around your spinal cord), your provider injects the numbing medicine. They then remove the needle.
6. Feeling the effects: Within minutes, your legs may feel warm, tingly, heavy and numb. The numbness moves upward to the level needed for your surgery. Your provider will check that you’re completely numb before surgery starts.

In the recovery room after surgery, the numbness will slowly wear off.

Are you awake with spinal anesthesia?

For a C-section, you’ll usually stay awake, or you may get light sedation to help you relax. For most other procedures, you may get sedation to help you relax and sleep.

Your anesthesia team will explain what to expect, because each person’s situation is different.

How long does it last?

Spinal anesthesia usually lasts a short time. For most people, the numbness lasts about 1.5 to three hours. The exact timing depends on the medicine and dose your provider uses.

Spinal anesthesia side effects

Most side effects are mild, but some can be more serious. Common side effects include:

• Backache
• Headache
• Low blood pressure
• Nausea
• Short-term hearing changes
• Vomiting

Rare but serious complications include:

• Bleeding near your spinal cord (spinal hematoma)
• Inflammation around your spinal cord (arachnoiditis)
• Nerve injury

Your provider will review these risks with you and help you decide what’s safest. Your anesthesia team will look at your medical history and choose the appropriate equipment to lessen the risk of any side effects.

Spinal anesthesia benefits

Spinal anesthesia offers several benefits for many types of surgery, including:

• It’s generally safe.
• You can stay awake or have less sedation.
• For C-sections, you can bond with your baby right after delivery.
• It provides strong pain management.
• It reduces the need for opioid pain medicines.
• It helps bowel function return sooner after surgery.
• You avoid breathing tube risks because you breathe on your own.

Spinal anesthesia recovery

Recovery from spinal anesthesia is usually quick. You should regain feeling in the previously numb areas the same day. As the numbness wears off, you’ll slowly regain feeling and strength in your legs. You might notice a mild tingling sensation.

Your care team will check that you can move your legs, feel touch and sit or stand safely before you leave the recovery area. Your providers will also make sure you can pee normally, since spinal anesthesia may affect bladder control for a short time.

It’s common to feel a little tired after surgery. You may have mild back soreness or a headache. These usually get better shortly after the procedure. Once the effects have fully worn off, you can start moving around again. You may need a little help at first.

Your provider will let you know when it’s safe to walk, eat and go home based on your surgery and recovery.

If something feels wrong or unusual, it’s always better to call your provider and ask.