Sensory blockade of S3 dermatome prevents pain during bladder catheterization

Abstract

Purpose: We often encounter patients who do not complain of pain on undergoing invasive urogenital or rectal procedures, despite incomplete epidural blockade of sacral cutaneous sensation. To clarify whether or not urethral pain is blocked faster than sacral cutaneous sensation during lumbar epidural anesthesia, we investigated the correlation between occurrence of urethral pain and loss of cold sensation in the S1-3 dermatomes.Methods: In 46 gynecological patients, Group A (n=22) received 15 ml of 2% mepivacaine via an epidural catheter inserted cephaladly. Group B (n=24) received 5 ml of 2% mepivacaine directly in the epidural needle directed caudally and 10 ml of 2% mepivacaine via the epidural catheter inserted cephaladly. A Foley catheter was inserted into the urethra 30 min after the injection.Results: Urethral pain, which was defined as a pained facial expression and/or complaint of pain, was observed in seven patients in Group A, and none in Group B. The caudad level of epidural blockade was significantly lower in patients without urethral pain (S3, median) than with urethral pain (L4) (P <0.05). In 39 patients without urethral pain, 19 (49%) experienced loss of cold sensation in the S1 dermatome, 27 (69%) in the S2 and 38 (97%) in the S3 25 min after the injection. ITH lumbar epidural anesthesia, cutaneous analgesia at the S1 dermatome takes longer to develop than at the S2-3 dermatomes because of the differences in nerve root size, even with sufficient spread of local anesthetic in the sacral area. 1 Of the 40 patients in our previous study, only 15 (38%) experienced loss of cold sensation in the S1 dermatome with 33 (83%) reporting loss in the S3 dermatome. 2 However, even in cases of incomplete epidural blockade of the sacral nerves, we often encounter patients who do not complain of unpleasant sensations or pain upon undergoing invasive urogenital or rectal procedures that are expected to cause pain. Clinical experiences like these suggest that urethral or rectal pain is blocked faster than the cutaneous cold sensation in the sacral nerves in the early stages of lumbar epidural anesthesia. To clarify this issue, we investigated the correlation between the occurrence of urethral viscer-REGIONAL ANESTHESIA A N D P A I N

Comparison of thoracic segmental spinal anaesthesia and lumbar spinal anaesthesia for percutaneous nephrolithotomy

“…It could be because of transient sacral sensory block due to possible downward spread of intrathecal LA. 16 In the present study no incidence of any neurological sequelae was noted, particularly in group T.…”

Loss of urinary voiding sensation due to herpes zoster

“…The innervation of urethral sensation is still not clear, but, urethral sensation is thought mainly to be innervated by the pudendal nerve (S2^4) [Elhilali and Win¢eld, 1994;Wesselmann et al, 1997]. The correlation between the occurrence of urethral pain and loss of cold sensation in S1^S3 dermatomes caused by epidural blockade of sacral cutaneous sensation recently was reported [Asato and Kanai, 2001]. S3 somatosensory blockade was the most important sacral level indicative of urethral sensation.…”

Feasibility of Awake Intravesical Botulinum Toxin Injection in Pediatric Neurogenic Bladder

“…Instead, we used documented sensory level as a proxy for bladder sensation, based on limited existing literature on the level of sensory blockade that correlates to the absence of urethral pain in adults. 16 Future studies should include direct assessment of sensation with catheterization, cystoscope placement and injection.…”

“…Sensation with catheterization was not routinely documented and so instead sensory level was dichotomized as S2 and above vs below as documented on neurological examinations. 16 Procedure details were extracted from the operative report. Use and timing of antibiotics, sedatives, intravenous analgesics and local anesthetics was determined from the medication administration record.…”