Planning the anesthesia for your total joint replacement involves planning for:

Anesthesia during surgery

Penn anesthesiologists and surgeons recommend spinal anesthesia for joint replacement surgery. Recent research suggests that complications may be reduced after surgery with spinal anesthesia compared to general anesthesia.

Pain management after surgery

To control your pain after surgery, we follow a protocol based on the best available evidence and the experience of our team. It involves using  regional anesthesia (nerve blocks) and oral and intravenous pain medications. We refer to our protocol as the MP3 (Multimodal Perioperative Pain Protocol).

Two types of anesthesia may be considered for joint replacement surgery: general anesthesia and spinal anesthesia.

General Anesthesia

General anesthesia keeps you in a deep sleep that affects your entire body. We will give you medicine through your vein that will put you to sleep.

Once you are asleep, the anesthesiologist will place a breathing tube down your windpipe. You will be breathing a mixture of oxygen, air and anesthetic gas that will make sure you stay asleep throughout the surgery.

Side effects of general anesthesia may include nausea, vomiting, sore throat/hoarse voice, or the potential for dental damage. General anesthesia can have more serious side effects that are far less common. Your anesthesia team will monitor your heart rate, blood pressure, breathing and body temperature throughout surgery to ensure your safety.

Advantages to using general anesthesia during hip or knee replacement surgery include:

• May be used for longer surgeries or when surgery may cause much blood loss
• Used if patient is not a candidate for spinal anesthesia

Spinal Anesthesia

In spinal anesthesia, numbing medication is injected into the fluid surrounding the spinal cord in the lower back. This will numb your legs and block all sensation in the lower half of your body for several hours.

Once you are in the operating room, routine monitors for blood pressure, heart rate, and oxygen saturation will be applied before you are given medication. While you are in a seated position, your skin is numbed with local numbing medication; a longer needle will then be applied through the numb area. After the needle reaches the desired space, numbing medication is injected into the fluid surrounding the spinal cord. You will then lie down on your back to allow the medicine to settle in. We will make sure that you are comfortable, safe, and sleepy.

You will not be awake during surgery. Spinal anesthesia provides surgical anesthesia and you will be given sedatives to help you relax and put you in a light sleep. The level of your sleepiness can be adjusted and you can be easily awakened, if needed. In other words, you will be sleepy but not completely out.

If you are not a candidate for spinal anesthesia, or your surgery is expected to be longer of involve more blood loss, general anesthesia will be chosen.

Side effects of spinal anesthesia may include short-term back pain, rare headaches, and trouble urinating. Nerve injury from needle trauma is very rare. Most of our patients don’t remember the spinal being performed. Patients sometimes ask if they should worry about spinal anesthesia causing paralysis. Spinal anesthesia is relatively safe and the chance of paralysis is very rare. The needles used are very small and we make sure that you are not taking any blood thinning medication prior to performance of spinal anesthesia.

Advantages to using spinal anesthesia during hip or knee replacement surgery include:

• You avoid general anesthesia and receive less medication, thus having fewer potential side effects.
• After surgery, you are more awake with a lower chance of developing nausea and vomiting.
• You experience less bleeding during surgery and fewer complications from blood clotting after surgery.
• After surgery, spinal anesthesia usually lasts beyond surgical time. This makes your pain management after surgery much smoother.

We believe early and aggressive pain control is necessary to increase your comfort and satisfaction and to improve the function of your new hip or knee. Our multimodal pain control protocol provides the most benefits while minimizing the side effects of individual medications, such as nausea, vomiting, itching, bowel and/or bladder retention.

Your medication will include a combination of acetaminophen (Tylenol), nonsteroidal anti-inflammatory drugs (such as aspirin, ibuprofen, naproxen, etc.), Gabapentin, and oral narcotics. In addition to the pain medications, we use regional anesthesia (nerve blocks) and inject numbing medicine into the joint during surgery.

Your pain management plan will be tailored to fit your specific needs. Your anesthesiologist, orthopaedic surgeons, and rehabilitation specialists all work together to adjust your specific pain management plan.

For patients undergoing total knee replacement, Regional Anesthesia (peripheral nerve blocks) is routinely part of the pain management protocol. Your knee joint is controlled by two nerves: the femoral nerve, which provides sensation for the front and sides of your knee, and the sciatic nerve, providing sensation for the back of your knee. For total knee replacement, femoral nerve blocks, or more commonly blocking one of its branches in the middle of the thigh, provide excellent pain control after surgery.

A nerve block is usually performed in the holding area or in the operating room before we begin your anesthesia. The nerve is located by using ultrasound technology. This helps us "see" the nerves and blood vessels in the area that we are blocking. We will give you relaxing medication that will make you sleepy during placement of the nerve block. Sometimes we use a small electric current to twitch your thigh muscles without pain to confirm the location of the nerve. 

A small catheter may be place next to the nerve. Local anesthetics will run continuously through the catheter starting immediately after the surgery. The catheter will be removed after we make sure that you are comfortable with the prescribed oral and/or intravenous medication; it can last up to two days.

If you have questions about anesthesia or pain management after surgery, email us your questions at: Anesthesia.questions@uphs.upenn.edu