The patient is placed in a comfortable, prone position. The patient's head should be neutral and facing straight down on the table. Proper support is necessary to keep the face from being smashed against the table. Aside from general discomfort, some patients may experience claustrophobia in this position. Thus, extra time should be spent positioning the head to alleviate discomfort and minimize patient anxiety. Several firm support pads should be placed under the patient's chest and forehead, elevating the face off the table. This leaves an opening for the patient's face, minimizing the closed-in feeling. Blowing oxygen across the face may also help to decrease claustrophobia. Conscious sedation is not routinely required, but it should be considered for patients who are anxious and less cooperative.
After identifying the target level on the patient's MRI, a target mark is made on the patient's neck utilizing AP fluoroscopy. The initial needle entrance is at the midportion of the lower of the two target vertebral bodies and midway between the pedicle and spinous process. Standard sterile preparation and drape are followed by anesthesia of the skin and subcutaneous tissues with 1% lidocaine buffered with sodium bicarbonate. A variety of needles are available to approach the cervical epidural space, but a 22-guage Tuohy needle is ideal because its blunt tip tends to push firm objects away, decreasing the likelihood of inadvertently puncturing the dura. After obtaining purchase with the Tuohy, the needle is advanced toward the interlaminar space with slight medial angulation, while visualizing the field from a contra-lateral oblique projection. This projection is obtained by rotating the tube about 45° opposite to the side of needle entrance, until the laminae take on a shingled appearance. This allows one to view the needle tip in tangent, and the needle is stopped just posterior to the spinal canal (Fig. 13). As the needle is advanced, its position should be checked in the AP projection periodically, to verify that it is directed toward the midline. After reaching the margin of the spinal canal and
returning to the oblique projection, the remainder of the needle advancement is done with a "hanging drop" technique. A few drops of iodinated contrast are placed on the needle hub ("hanging" there), giving a convex configuration (Fig. 14). As the needle is slowly advanced and finally positioned into the epidural space, the contrast dome will drop down the hub, heralding epidural location.
Once the contrast is imbibed, the needle-tip position is verified by instilling an additional 2 mL of contrast, visualized in real time with both oblique and AP projections. Epidural contrast should circumscribe the outline of the dura (Fig. 15). If the contrast instead has a diluted appearance and wraps around the spinal cord, simulating a myelogram, intrathecal injection is likely. The procedure should be terminated and reattempted in about seven days. Rarely, the contrast conforms to a tubular or serpentine pattern and washes away, due to needle position in an epidural vein. Often a minute adjustment to the needle tip will extricate
it from the vessel. If the repeated needle adjustment is unsuccessful, another level should be accessed.
With satisfactory positioning, 12 mg of Celestone Soluspan or 80 mg Kenalog-40 is instilled for an average-sized adult. An additional 2mL of 0.25% bupivicaine provides immediate pain relief. Higher concentrations of bupivicaine are not used because of the risk of motor block. During the injection, there should not be any resistance; if any force is required, a malposition of the needle should be suspected. During the injection, patients may complain of pressure at the site of the injection or dull or shooting pain. These symptoms should subside with decreasing injection rate. After the injection, the needle is removed, the overlying puncture site is cleansed with alcohol, and an adhesive bandage is placed. The patient is assisted while rising slowly. The postprocedure routine is the same as for lumbar injections.
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Deal With Your Pain, Lead A Wonderful Life An Live Like A 'Normal' Person. Before I really start telling you anything about me or finding out anything about you, I want you to know that I sympathize with you. Not only is it one of the most painful experiences to have backpain. Not only is it the number one excuse for employees not coming into work. But perhaps just as significantly, it is something that I suffered from for years.