Central nerve blocks performed by injecting anesthetic solutions intrathecally (into the subarachnoid space), into the epidural space, or into the caudal canal (an extension of the epidural space).
These anesthetics are employed for procedures on the lower abdomen and lower extremities. The composition and concentration of the anesthetic solution will determine the duration of the block. The position of the patient immediately following the injection of the anesthetic solution influences the level and distribution of the block.
Preparation of the Patient:
Position of the patient is determined by the type of block being administered, procedure being performed, condition of the patient, and preference of the anesthetist. Position may be sitting, lateral, or prone.
- Sitting: With back arched and feet supported on a stool (spinal or epidural)
- Lateral: With knees, hips, back, and neck flexed (spinal or epidural)
- Prone: Flexed at the waist (caudal or hypobaric spinal)
Following the injection of the agent (after an interval determined by anesthetist), the patient is placed in the selected operative position.
For prolonged procedures or for post-operative analgesia, continuous epidural or caudal anesthesia is established by inserting a catheter into the appropriate space at the time of the initial needle placement. Increments of anesthetic solution may then be administered.
Skin Preparation and Draping:
Usually performed by the anesthetist. These materials may be included in the prepackaged disposal tray.
- Stool (for patient’s feet, sitting position)
- Sitting tool (for anesthetist)
- Appropriate sterile disposable tray (spinal, epidural, caudal)
- Additional agents, needles, catheters, etc (as requested)
- The circulator may be requested to set up an intravenous line.
- The circulator is usually requested to assist in maintaining the patient’s position during administration of the block.
- The circulator (in addition to anesthetist) should closely observe the patient for signs of respiratory distress caused by the sedation or by the inadvertent administration of a “high” spinal, which would result in depression or paralysis of the respiratory muscles and require immediate intubations and ventilation.
- Special care must be taken to protect the patient in order to avoid injuries, that is, burns, neurological damage, pressure sores, or other traumas to the patient who is unable to sense the injuries while receiving an anesthetic.
- According to some authorities, in order to avoid post spinal headache, patients may be instructed preoperatively and reminded postoperatively that they should remain at bedrest without raising their heads for 24 to 48 hours.
- Adhesive tape secures intravenous line and anesthetic catheter.
- Do not dispose of the tray until the anesthetist has the appropriate information needed for the anesthetic record.
- The patient, although often sedated, may be alert enough to hear; therefore, discussion of the diagnosis, other medical information, and idle conversation should be limited accordingly.
- The patient’s privacy should always be maintained.