The Anatomical Distribution of the Pudendal Nerve Block Injection: A Cadaveric Study

Pudendal Nerve Block Analgesia at the Time of Vaginal Surgery: A Randomized, Double-Blinded, Sham-Controlled Trial

IMPORTANCE

Effective opioid-sparing postoperative analgesia requires a multimodal approach. Regional nerve blocks augment pain control in many surgical fields and may be applied to pelvic floor reconstruction.

OBJECTIVE

This study aimed to evaluate the impact of pudendal nerve block on postoperative pain control and opioid consumption after vaginal surgery.

STUDY DESIGN

In this randomized, double-blind, sham-controlled trial, we enrolled women undergoing pelvic reconstruction, excluding patients with chronic pelvic pain or contraindications to nonnarcotic analgesia. Patients were randomized to transvaginal pudendal nerve block (9 mL 0.25% bupivacaine and 1 mL 40 mg/mL triamcinolone) or sham injection (10 mL normal saline). Primary outcomes were pain scores and opioid requirements. Sixty patients were required to show a 20-mm difference on a 100-mm visual analog scale (VAS).

RESULTS

We randomized 71 patients: 36 pudendal block and 35 sham. Groups were well matched in baseline characteristics and surgery type. Prolapse repairs were most common (n = 63 [87.5%]), and there was no difference in anesthetic dose or operative time. Pain scores were equivalent in the postanesthesia care unit (mean VAS, 53.1 [block] vs 56.4 [sham]; P = 0.517) and on postoperative day 4 (mean VAS, 26.7 [block] vs 35.5 [sham]; P = 0.131). On postoperative day 1, the intervention group reported less pain, but this did not meet our 20 mm goal for clinical significance (mean VAS, 29.2 vs 42.5; P = 0.047). A pudendal block was associated with lower opioid consumption at all time points, but this was not statistically significant.

CONCLUSIONS

Surgeon-administered pudendal nerve block at the time of vaginal surgery may not significantly improve postoperative pain control or decrease opioid use.

Cone-Beam CT With Enhanced Needle Guidance and Augmented Fluoroscopy Overlay: Applications in Interventional Radiology

Please see the Editorial Comment by Jose L. del Cura discussing this article. Digital flat panel detector cone-beam CT (CBCT), introduced in the early 2000s, was historically used in interventional radiology primarily for liver-directed therapies. However, contemporary advanced imaging applications, including enhanced needle guidance and augmented fluoroscopy overlay, have evolved substantially over the prior decade, and now work synergistically with CBCT guidance to overcome limitations encountered with other imaging modalities. CBCT with advanced imaging applications has become increasingly used to facilitate a broad range of minimally invasive procedures, particularly relating to pain and musculoskeletal interventions. Potential advantages of CBCT with advanced imaging applications include greater accuracy for complex needle paths, improved targeting in the presence of metal artifact, enhanced visualization during injection of contrast media or cement, increased ease when space in the gantry is limited, and reduced radiation doses versus conventional CT guidance. Nonetheless, CBCT guidance remains underutilized, partly relating to lack of familiarity with the technique. This article describes the practical implementation of CBCT with enhanced needle guidance and augmented fluoroscopy overlay and depicts the technique's application for an array of interventional radiology procedures, including epidural steroid injections, celiac plexus block and neurolysis, pudendal block, spine ablation, percutaneous osseous ablation fixation and osteoplasty, biliary recanalization, and transcaval type II endoleak repair.

Preoperative pudendal block with liposomal and plain bupivacaine reduces pain associated with posterior colporrhaphy: a double-blinded, randomized controlled trial

BACKGROUND

Pelvic reconstructive surgery may cause significant postoperative pain, especially with posterior colporrhaphy, contributing to a longer hospital stay and increased pain medication utilization. Regional blocks are being increasingly utilized in gynecologic surgery to improve postoperative pain and decrease opioid usage, yet preoperative pudendal blocks have not been used routinely during posterior colporrhaphy.

OBJECTIVE

This study aimed to compare the effect of preoperative regional pudendal nerve block using a combination of 1.3% liposomal and 0.25% plain bupivacaine vs 0.25% plain bupivacaine alone on vaginal pain after posterior colporrhaphy on postoperative days 1, 2, and 3. We hypothesized that there would be a reduction in vaginal pain scores for the study group vs the control group over the first 72 hours.

STUDY DESIGN

This was a double-blinded, randomized controlled trial that included patients undergoing a posterior colporrhaphy, either independently or in conjunction with other vaginal or abdominal reconstructive procedures. Patients were block randomized to receive 20 mL of either a combination of 1.3% liposomal and 0.25% plain bupivacaine (study) or 20 mL of 0.25% plain bupivacaine (control) in a regional pudendal block before the start of surgery. Double blinding was achieved by covering four 5-mL syringes containing the randomized local anesthetic. After induction of anesthesia, a pudendal nerve block was performed per standard technique (5 mL superiorly and 5 mL inferiorly each ischial spine) using a pudendal kit. The primary outcome was to evaluate postoperative vaginal pain using a visual analog scale on postoperative days 1, 2, and 3. Secondary outcomes included total analgesic medication usage through postoperative day 3, postoperative voiding and defecatory dysfunction, and impact of vaginal pain on quality of life factors.

RESULTS

A total of 120 patients were enrolled (60 in each group). There were no significant differences in demographic data, including baseline vaginal pain (P=.88). Postoperative vaginal pain scores were significantly lower in the combined liposomal and bupivacaine group at all time points vs the plain bupivacaine group. Median pain scores for the study and control groups, respectively, were 0 (0-2) and 2 (0-4) for postoperative day 1 (P=.03), 2 (1-4) and 3 (2-5) for postoperative day 2 (P=.05), and 2 (1-4) and 3 (2-5) for postoperative day 3 (P=.02). Vaginal pain scores increased from postoperative day 1 to postoperative days 2 and 3 in both groups. There was a significant decrease in ibuprofen (P=.01) and acetaminophen (P=.03) usage in the study group; however, there was no difference between groups in total opioid consumption through postoperative day 3 (P=.82). There was no difference in successful voiding trials (study 72%, control 82%, P=.30), return of bowel function (P>.99), or quality of life factors (sleep, stress, mood, and activity).

CONCLUSION

Preoperative regional pudendal block with a combination of liposomal and plain bupivacaine provided more effective vaginal pain control than plain bupivacaine alone for reconstructive surgery that included posterior colporrhaphy. Given the statistically significant decrease in vaginal pain in the study group, this block may be considered as a potential adjunct for multimodal pain reduction in this patient population.