Paracervical Block or Uterosacral Ligament Infiltration for Benign Minimally Invasive Hysterectomy: A Systematic Review and Meta-analysis
Authors: Wang Alexander S. , Ouyang Chensi , Carrillo Jorge F. , Feranec Jessica B. , Lamvu Georgine M. 
Published: June 2021

Objective
The aim of this study was to estimate the efficacy of preemptive paracervical block or uterosacral ligament infiltration in reducing postoperative pain and opioid consumption after benign minimally invasive hysterectomy.

Data Sources
We searched MEDLINE, Cochrane Library, Embase, ClinicalTrials.gov, and Google Scholar from inception until February 2020.

Methods of Study Selection
We identified randomized placebo-controlled trials assessing the primary outcome of pain and opioid consumption after paracervical block or uterosacral infiltration in benign laparoscopic, vaginal, or robotic hysterectomy. Two investigators evaluated studies for risk of bias and quality of evidence.

Tabulation, Integration, and Results
We reviewed 219 abstracts; 6 studies met the inclusion criteria: 3 using paracervical block (2 vaginal and 1 laparoscopic) and 3 using uterosacral ligament infiltration (all vaginal). Two studies were included in the meta-analysis (both vaginal hysterectomy). Because of lack of numerical data, or comparison, the other 4 studies are reported in narrative form.
Three controlled trials reported a moderate benefit from paracervical block up to 8 hours after vaginal and 4 hours after laparoscopic surgery. Meta-analysis could not be performed because of the lack of numerical data for pooling results or the lack of a laparoscopic hysterectomy comparison group. Three trials reported that uterosacral infiltration decreases pain up to 6 hours after vaginal hysterectomy, and meta-analysis pooling the results of 2 of these studies demonstrated improvement in pain up to 4 hours on a 0- to 100-mm visual analog scale for pain (−19.97 mm; 95% confidence interval, −29.02 to −10.91; P < 0.000).
Five trials reported a moderate reduction in cumulative opioid use within 24 hours after vaginal surgery for both paracervical block and uterosacral infiltration. Meta-analysis was not performed for paracervical block because only 1 trial provided suitable data for pooling. Meta-analysis pooling the results of 2 trials of uterosacral infiltration demonstrated opioid consumption of 20.73 morphine milligram equivalents less compared with controls (95% confidence interval, −23.54 to −17.91; P < 0.000).

Conclusions
There were a total of 6 randomized placebo-controlled studies evaluated in this study. Although a meta-analysis was unable to be performed for all studies because of lack of comparison groups or numerical data, there is evidence that preemptive uterosacral ligament infiltration may reduce postoperative pain and opioid consumption after vaginal hysterectomy. Our study does not allow us to make any substantive conclusions on the use of paracervical block in vaginal hysterectomy or the use of either type of injection in laparoscopic or robotic hysterectomy.

Target Audience
Obstetricians and gynecologists, family physicians

Learning Objectives
After completing this activity, the learner should be better able to describe the afferent neuroanatomy pathway of the uterus and cervix; assess the literature on the use of preemptive paracervical block and uterosacral ligament infiltration in benign minimally invasive hysterectomy; analyze the role of preemptive paracervical block and uterosacral ligament infiltration in the management of postoperative pain after benign minimally invasive hysterectomy; and identify the effect of preemptive paracervical block and uterosacral ligament infiltration on opioid consumption after benign minimally invasive hysterectomy.