Clinical Trial – Minimal Effective Dose of Hyperbaric Spinal Bupivacaine for Saddle Block
The optimal anesthetic technique would provide excellent operating conditions, rapid
recovery, early discharge, no postoperative side effects, and high patient’s satisfaction. In
addition to increasing the quality and decreasing the costs of the anesthetic services (1).
Selective spinal anesthesia (SSA) -spinal block with minimal effective doses for a specific
type of surgery – has become very popular technique) 2(for some orthopedic and gynecological
surgeries [3-9].
Saddle anesthesia is a SSA directs a small bolus of hyperbaric local anesthetic, towards
S4-S5 and coccygeal nerve roots (11), and is commonly utilized for perianal surgeries
(11-14). Hyperbaric bupivacaine has been safely, replaced hyperbaric Lidocaine for saddle
block (11, 12).
Although Saddle blocks at different low doses of hyperbaric bupivacaine (1.5- 4 mg) have been
used previously for mi¬nor perianal surgeries (11, 13, 14), the optimal effective dose has
yet to be determined.
The objective of this study is to determine the minimal effective dose of hyperbaric spinal
bupivacaine required to induce a reliable and satisfactory saddle block for perianal
surgeries (using a modified Dixon’s up-and-down method.