Surgeons almost exclusively request an interscalene block for surgery on the shoulder or upper arm. This block provides excellent surgical anesthesia in a safe and effective manner.
Once you arrive in the operating room, the anesthesiologist may provide a small amount of sedation before the performance of the block. This will help relieve you of most of your anxiety concerning the anesthetic. He or she will place EKG stickers on your chest and neck, a blood pressure will be measured, and a light sensor to measure your oxygen will be placed on an ear or finger. Next, they will clean your neck with an iodine based solution. Your anesthesiologist will begin examining your neck, perhaps asking you to lift your head off the table or sniff with your nose. These maneuvers help the anesthesiologist determine the correct point of injection.
Next, he or she will slowly insert a very thin, 1-inch needle into the side of your neck. (This is almost always less uncomfortable than it sounds.) Shortly thereafter, you will feel a “funny bone” sensation at a location different than the needle. It may feel like a sensation of electricity or an involuntary twitch. Without moving, you will let your anesthesiologist know where you felt that sensation. Your anesthesiologist will determine if the response is optimal and then begin injecting lidocaine-like medicine to numb your shoulder and arm. An alternative method is to use small amounts of electricity to determine the location of nerves for the shoulder. It is the attending anesthesiologist who will determine which method is optimal for you.
Over the next 15 to 20 minutes, you will be positioned in a semi-sitting/reclining pose. This offers excellent exposure to your shoulder for the surgeon. Most anesthesiologists provide relatively deep levels of sedation. It allows better blood pressure control, less bleeding, and ultimately more patient comfort, while reducing the incidence of episodes of dangerously slow heart rates. Ultimately, your level of sedation is the decision of your attending anesthesiologist.
At the end of surgery, when the sedation wears off, you will notice a few things. First, you won’t be able to move or feel your shoulder, arm, and sometimes your hand. Your voice can be very horse and you may feel that you weren’t taking as deep a breath as you did before surgery. These are normal experiences, and they will disappear as the block wears off.
The block can last anywhere from 4 to 18 hours, depending on which medicines are used.
As with any anesthetic, there are risks and benefits to interscalene blocks. These particulars can be discussed with your anesthesiologist before your surgery.