Anesthesia for Your Knee Replacement Surgery: What to Expect
- Jen Overton
- Jun 4
- 9 min read
Updated: Nov 5
If you’re preparing for knee replacement surgery, you may be focused on the procedure itself and how it will improve your mobility and quality of life. But the thought of anesthesia—often discussed incompletely before the day of surgery—can bring up questions or even anxiety. This is why I’m here to walk you through what to expect from anesthesia during your knee replacement, including the types of anesthesia used, the day-of-surgery experience, and whether you might go home the same day or stay in the hospital. My goal is to help you feel informed, prepared, and confident, so you can focus on your recovery.
Why Anesthesia Matters for Your Knee Replacement
Knee replacement surgery, also called total knee arthroplasty or partial knee arthroplasty, involves replacing damaged parts of your knee joint with artificial components. Anesthesia ensures you’re comfortable and pain-free during the procedure, and it can also help manage pain afterward. For this surgery, spinal anesthesia is commonly used to numb the lower half of your body, often combined with regional nerve blocks to target pain in the knee and surrounding areas. These methods work together to provide a smooth surgical experience and support your recovery. Your health status and the surgeon's preference decide whether your procedure can be performed as outpatient (same-day) surgery or if a short hospital stay is needed.
Below, I’ll explain the anesthesia process, what you’ll experience on the day of surgery, and how we tailor care to your needs.
Your Day-of-Surgery Anesthesia Experience
Before Surgery: Meeting Your Anesthesia Team
On the morning of your surgery, you’ll arrive at the hospital or surgical center and check into the preoperative area. If you’re a candidate for outpatient surgery (meaning you’re healthy, have good support at home, and your surgeon agrees), you may go home the same day. Otherwise, you might stay in the hospital for 1–3 days for additional monitoring and recovery support. Your anesthesia team will discuss this with you based on your health and the surgical plan.
In the preoperative area, you’ll meet your anesthesia provider—a nurse anesthetist like me or an anesthesiologist. We’ll review your medical history, medications, and any allergies, and we’ll confirm the anesthesia plan. This is your chance to ask questions or share concerns. If you’re feeling anxious, let us know—we can offer reassurance or a mild sedative to help you relax before heading to the operating room.
Spinal Anesthesia: What to Expect
Spinal anesthesia is a common choice for knee replacement surgery. It numbs your body from the waist down, so you feel no pain during the procedure, and it can provide pain relief for several hours afterward.
Purpose of Spinal Anesthesia
Spinal anesthesia allows your surgeon to perform the knee replacement while you’re comfortable and pain-free. It also reduces the need for general anesthesia (being fully asleep), which can mean fewer side effects like nausea or grogginess. For many patients, spinal anesthesia supports a faster recovery, especially for outpatient procedures.
The Process
The spinal block may be performed in the pre-operative holding area or in the operating room. Here’s what happens:
Positioning: You’ll sit up or lie on your side, curling forward slightly to open the space between your lower back vertebrae. We’ll help you get into a comfortable position and talk you through each step.
Cleaning and Numbing: We clean the skin on your lower back with a cool antiseptic solution. Then, we inject a small amount of local anesthetic to numb the area, which feels like a quick pinch that fades quickly.
Placing the Spinal: Using a very thin needle, we deliver a small dose of anesthetic medication into the fluid around your spinal cord. This takes just a few seconds, and you may feel slight pressure but no sharp pain. The entire process usually takes about 5 minutes.
What You’ll Feel: Within a minute or two, your legs will feel warm, tingly, and heavy, and you’ll lose sensation in your lower body. This means the spinal is working. You may also receive light sedation through an IV to keep you relaxed or drowsy during surgery.
We monitor your vital signs closely during the procedure to ensure your safety and comfort. The spinal anesthesia typically wears off a few hours after surgery, allowing you to start moving your legs as you recover.
Want to know even more about spinal anesthesia? Click the image below to read Understanding Spinal and Epidural Anesthesia: Your Guide to Safe, Comfortable Care.
Regional Nerve Blocks: What to Expect
In addition to spinal anesthesia, your anesthesia team may perform a regional nerve block, such as a femoral nerve block or an adductor canal block, to manage pain in your knee after surgery. These blocks are often done to enhance comfort during recovery, especially for outpatient procedures or to reduce pain medication needs during a hospital stay.
Purpose of Regional Nerve Blocks
A nerve block targets specific nerves that carry pain signals from your knee, providing focused pain relief for 12–24 hours (or longer, depending on the medication used). This can make your first day of recovery more comfortable and help you start physical therapy sooner, which is key to a successful outcome.
The Process
The nerve block is usually performed in the preoperative area or just after the spinal anesthesia, using ultrasound for precision. Here’s how it works:
Positioning: You’ll lie on your back, and we’ll position your leg to access the nerves in your thigh or groin area (depending on the block).
Cleaning and Numbing: We clean the skin with an antiseptic and inject a local anesthetic to numb the area, which feels like a brief sting.
Ultrasound Guidance: Using an ultrasound wand, we locate the nerves (you won’t feel the ultrasound). We then insert a small needle to deliver numbing medication near the nerves. You might feel slight pressure, but it’s typically not painful. The process takes 5–10 minutes.
What You’ll Feel: After the block, your knee and thigh may feel numb or weak, which is normal. The numbness will gradually wear off, but the pain relief often lasts longer, helping you manage discomfort as you begin recovery.
If you’re concerned about needles or the sensation, let us know—we can explain each step or use distraction techniques to keep you comfortable. Also, IV sedation medication is often administered prior to the regional block which makes it even easier to manage.
What Happens During and After Surgery
Once the spinal anesthesia (and nerve block, if used) is in place, you'll be moved to the operating table. We’ll place monitors to track your heart rate, blood pressure, and oxygen levels, using noninvasive devices like sticky patches or a finger clip. If you’re receiving sedation, you’ll feel relaxed or drowsy, and the surgery will feel like it passes quickly while you took a nice nap.
During the procedure, your anesthesia team stays by your side, monitoring you closely and adjusting medications as needed. The surgery typically lasts 1–2 hours. Afterward, you’ll go to the recovery room, where nurses will monitor you as the spinal anesthesia begins to wear off. You may feel tingling or warmth in your legs as sensation returns, and the nerve block (if used) should continue to provide some pain relief.
If you’re having outpatient surgery, you’ll likely go home later that day once you’re stable, can move with assistance, and have a plan for pain management and physical therapy. If you’re staying in the hospital, we’ll ensure you’re comfortable with pain medications and support for 1–3 days, depending on your recovery needs.
What You’ll Feel in Recovery
From the Spinal: As the spinal wears off, you’ll regain feeling and movement in your legs over a few hours. You might feel stiff or sore as sensation returns, but we’ll provide pain medication as needed.
From the Nerve Block: Your knee may feel numb or weak for up to 24 hours, which helps with early pain control.
General Recovery: You might feel groggy if sedation was used, and some patients experience mild nausea or a dry mouth, which we can treat. The recovery room team will help you feel comfortable and oriented.
Why This Combination Works
Spinal anesthesia combined with a regional nerve block and sedation is a very effective approach for knee replacement surgery. The spinal provides complete pain relief during the procedure, avoiding the need for general anesthesia and its potential side effects. The nerve block extends pain control into the first day or two of recovery, helping you start physical therapy with less discomfort. The sedation, or MAC, allows you to snooze through the whole procedure. This combination supports both outpatient and inpatient recoveries, allowing you to focus on healing and regaining mobility.
Alternative Anesthesia Options
While spinal anesthesia with a nerve block is common, other options may be considered based on your health, preferences, or the surgical plan:
General Anesthesia: If spinal anesthesia isn’t suitable (e.g., due to certain medical conditions or personal preference), general anesthesia can be used to keep you fully asleep during surgery. Pain is managed afterward with medications or a nerve block.
Epidural Anesthesia: Similar to spinal anesthesia, an epidural involves placing a small catheter in your lower back to deliver numbing medication. This is less common for knee replacement but may be used if longer-term pain control is needed for some reason, maybe due to an expected prolonged surgery.
Your anesthesia team will work with you and your surgeon to choose the best approach, ensuring it’s safe and tailored to your needs. If you have concerns (e.g., about staying awake or managing pain), share them with us—we’re here to listen and adjust the plan.
Want to learn more about general anesthesia, just in case? Great! Click the image below to read General Anesthesia: The Patient Experience from Start to Finish.
Outpatient vs. Inpatient: What to Expect
Knee replacement surgery can often be done as an outpatient procedure, meaning you go home the same day. This is typically an option if you’re in good overall health, have a strong support system at home, and can start physical therapy right away. Outpatient surgery allows you to recover in the comfort of your home, but it requires careful planning for pain management, mobility aids (like crutches or a walker), and follow-up care.
If you have other health conditions (like heart or lung issues) or need more support, a hospital stay of 1–3 days may be recommended. This allows for closer monitoring, IV pain medications if needed, and physical therapy in a controlled setting. Your surgeon and anesthesia team will discuss which option is best for you, and we’ll ensure you’re prepared for a smooth transition to recovery.
Tips to Prepare and Reduce Anxiety
Feeling prepared can ease your nerves and set you up for a successful surgery. Here are some tips:
Ask Questions: Write down any concerns about anesthesia or recovery and bring them to your preoperative visit or ask on the day of surgery. We’re here to clarify everything.
Practice Relaxation: If you’re feeling anxious, try slow, deep breathing or visualization techniques. Let us know if you’d like help with relaxation strategies.
Plan for Recovery: Arrange for someone to drive you home (especially for outpatient surgery) and help with daily tasks for the first few days. Have mobility aids and a comfortable recovery space ready.
Trust Your Team: Your anesthesia and surgical teams are dedicated to your safety and comfort. We’ll monitor you closely and adjust care to keep you at ease.
Still worried about anesthesia for your knee replacement? Click the image below to read How to Overcome the Fear of Anesthesia: Tips for a Better Surgery Experience
Final Thoughts
Anesthesia for knee replacement surgery is designed to keep you comfortable, safe, and pain-free, allowing your surgeon to focus on restoring your mobility. By understanding spinal anesthesia, regional nerve blocks, and what to expect on the day of surgery, you can approach your procedure as informed as possible. Whether you go home the same day or stay in the hospital, your anesthesia team is here to support you every step of the way, helping you start your journey to a stronger, more active life.
Feel free to re-read this article leading up to your surgery day. Close your eyes and visualize the process and practice observing what is happening and appreciating the expertise of those whose purpose lies in caring only for you.
If you have more questions or want to learn about anesthesia for other procedures, explore this website, reach out, or talk to your healthcare team. I'm also here to help you feel ready and assured. Remember that prepared patients have better outcomes!
Want to check out more Articles about anesthesia for a different surgical procedure? Click on the Worry-free anesthesia icon to learn more!
**Information provided is intended as general healthcare information for the public and should be used as a guide. This information should not be substituted for the specific personal advice recommended by your own healthcare team who are familiar with your specific health history.*
Comments